From 0206de2d2c62848778240760461020f3b9261446 Mon Sep 17 00:00:00 2001
From: James Turner <zakalawe@mac.com>
Date: Wed, 25 Sep 2013 13:54:16 +0100
Subject: [PATCH] Relocate Sqlite3 sources, upgrade to 3.8.0.2

Move sqlite source to a separate location, and build with
an intermediate library target. This permits us to set compile options
easier, including an important one, NDEBUG, which improves performance.

Sqlite 3.8.0.2 also includes an updated query planner which may improve
some queries, to be tested.
---
 3rdparty/CMakeLists.txt                       |     4 +
 3rdparty/sqlite3/CMakeLists.txt               |     4 +
 .../sqlite3/fg_sqlite3.h                      |   396 +-
 {src/Navaids => 3rdparty/sqlite3}/sqlite3.c   | 21802 +++++++++-------
 CMakeLists.txt                                |    15 +-
 src/Main/CMakeLists.txt                       |     5 -
 src/Navaids/CMakeLists.txt                    |     5 -
 src/Navaids/NavDataCache.cxx                  |    16 +-
 8 files changed, 12801 insertions(+), 9446 deletions(-)
 create mode 100644 3rdparty/CMakeLists.txt
 create mode 100644 3rdparty/sqlite3/CMakeLists.txt
 rename src/Navaids/sqlite3.h => 3rdparty/sqlite3/fg_sqlite3.h (94%)
 rename {src/Navaids => 3rdparty/sqlite3}/sqlite3.c (90%)

diff --git a/3rdparty/CMakeLists.txt b/3rdparty/CMakeLists.txt
new file mode 100644
index 000000000..5c2623891
--- /dev/null
+++ b/3rdparty/CMakeLists.txt
@@ -0,0 +1,4 @@
+
+if (NOT SYSTEM_SQLITE)
+    add_subdirectory(sqlite3)
+endif()
diff --git a/3rdparty/sqlite3/CMakeLists.txt b/3rdparty/sqlite3/CMakeLists.txt
new file mode 100644
index 000000000..551c562ff
--- /dev/null
+++ b/3rdparty/sqlite3/CMakeLists.txt
@@ -0,0 +1,4 @@
+
+add_definitions(-DSQLITE_OMIT_LOAD_EXTENSION)
+add_definitions(-DNDEBUG)
+add_library(fgsqlite3 sqlite3.c)
diff --git a/src/Navaids/sqlite3.h b/3rdparty/sqlite3/fg_sqlite3.h
similarity index 94%
rename from src/Navaids/sqlite3.h
rename to 3rdparty/sqlite3/fg_sqlite3.h
index fe05a05ca..924b01197 100644
--- a/src/Navaids/sqlite3.h
+++ b/3rdparty/sqlite3/fg_sqlite3.h
@@ -107,9 +107,9 @@ extern "C" {
 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
 ** [sqlite_version()] and [sqlite_source_id()].
 */
-#define SQLITE_VERSION        "3.7.13"
-#define SQLITE_VERSION_NUMBER 3007013
-#define SQLITE_SOURCE_ID      "2012-06-11 02:05:22 f5b5a13f7394dc143aa136f1d4faba6839eaa6dc"
+#define SQLITE_VERSION        "3.8.0.2"
+#define SQLITE_VERSION_NUMBER 3008000
+#define SQLITE_SOURCE_ID      "2013-09-03 17:11:13 7dd4968f235d6e1ca9547cda9cf3bd570e1609ef"
 
 /*
 ** CAPI3REF: Run-Time Library Version Numbers
@@ -219,7 +219,8 @@ SQLITE_API int sqlite3_threadsafe(void);
 ** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
 ** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
-** is its destructor.  There are many other interfaces (such as
+** and [sqlite3_close_v2()] are its destructors.  There are many other
+** interfaces (such as
 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
 ** [sqlite3_busy_timeout()] to name but three) that are methods on an
 ** sqlite3 object.
@@ -266,28 +267,46 @@ typedef sqlite_uint64 sqlite3_uint64;
 /*
 ** CAPI3REF: Closing A Database Connection
 **
-** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
-** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
-** successfully destroyed and all associated resources are deallocated.
+** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
+** for the [sqlite3] object.
+** ^Calls to sqlite3_close() and sqlite3_close_v2() return SQLITE_OK if
+** the [sqlite3] object is successfully destroyed and all associated
+** resources are deallocated.
 **
-** Applications must [sqlite3_finalize | finalize] all [prepared statements]
-** and [sqlite3_blob_close | close] all [BLOB handles] associated with
-** the [sqlite3] object prior to attempting to close the object.  ^If
-** sqlite3_close() is called on a [database connection] that still has
-** outstanding [prepared statements] or [BLOB handles], then it returns
-** SQLITE_BUSY.
+** ^If the database connection is associated with unfinalized prepared
+** statements or unfinished sqlite3_backup objects then sqlite3_close()
+** will leave the database connection open and return [SQLITE_BUSY].
+** ^If sqlite3_close_v2() is called with unfinalized prepared statements
+** and unfinished sqlite3_backups, then the database connection becomes
+** an unusable "zombie" which will automatically be deallocated when the
+** last prepared statement is finalized or the last sqlite3_backup is
+** finished.  The sqlite3_close_v2() interface is intended for use with
+** host languages that are garbage collected, and where the order in which
+** destructors are called is arbitrary.
 **
-** ^If [sqlite3_close()] is invoked while a transaction is open,
+** Applications should [sqlite3_finalize | finalize] all [prepared statements],
+** [sqlite3_blob_close | close] all [BLOB handles], and 
+** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
+** with the [sqlite3] object prior to attempting to close the object.  ^If
+** sqlite3_close_v2() is called on a [database connection] that still has
+** outstanding [prepared statements], [BLOB handles], and/or
+** [sqlite3_backup] objects then it returns SQLITE_OK but the deallocation
+** of resources is deferred until all [prepared statements], [BLOB handles],
+** and [sqlite3_backup] objects are also destroyed.
+**
+** ^If an [sqlite3] object is destroyed while a transaction is open,
 ** the transaction is automatically rolled back.
 **
-** The C parameter to [sqlite3_close(C)] must be either a NULL
+** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
+** must be either a NULL
 ** pointer or an [sqlite3] object pointer obtained
 ** from [sqlite3_open()], [sqlite3_open16()], or
 ** [sqlite3_open_v2()], and not previously closed.
-** ^Calling sqlite3_close() with a NULL pointer argument is a 
-** harmless no-op.
+** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
+** argument is a harmless no-op.
 */
-SQLITE_API int sqlite3_close(sqlite3 *);
+SQLITE_API int sqlite3_close(sqlite3*);
+SQLITE_API int sqlite3_close_v2(sqlite3*);
 
 /*
 ** The type for a callback function.
@@ -406,6 +425,8 @@ SQLITE_API int sqlite3_exec(
 #define SQLITE_FORMAT      24   /* Auxiliary database format error */
 #define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
 #define SQLITE_NOTADB      26   /* File opened that is not a database file */
+#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
+#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
 #define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
 #define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
 /* end-of-error-codes */
@@ -455,14 +476,32 @@ SQLITE_API int sqlite3_exec(
 #define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
 #define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
 #define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
+#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
+#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
+#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
 #define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
 #define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
+#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
 #define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
 #define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
+#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
 #define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
 #define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
 #define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
+#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
 #define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
+#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
+#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
+#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
+#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
+#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
+#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
+#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
+#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
+#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
+#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
+#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
+#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
 
 /*
 ** CAPI3REF: Flags For File Open Operations
@@ -498,7 +537,7 @@ SQLITE_API int sqlite3_exec(
 ** CAPI3REF: Device Characteristics
 **
 ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
-** object returns an integer which is a vector of the these
+** object returns an integer which is a vector of these
 ** bit values expressing I/O characteristics of the mass storage
 ** device that holds the file that the [sqlite3_io_methods]
 ** refers to.
@@ -702,6 +741,9 @@ struct sqlite3_io_methods {
   void (*xShmBarrier)(sqlite3_file*);
   int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
   /* Methods above are valid for version 2 */
+  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
+  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
+  /* Methods above are valid for version 3 */
   /* Additional methods may be added in future releases */
 };
 
@@ -836,6 +878,38 @@ struct sqlite3_io_methods {
 ** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
 ** file control occurs at the beginning of pragma statement analysis and so
 ** it is able to override built-in [PRAGMA] statements.
+**
+** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
+** ^The [SQLITE_FCNTL_BUSYHANDLER]
+** file-control may be invoked by SQLite on the database file handle
+** shortly after it is opened in order to provide a custom VFS with access
+** to the connections busy-handler callback. The argument is of type (void **)
+** - an array of two (void *) values. The first (void *) actually points
+** to a function of type (int (*)(void *)). In order to invoke the connections
+** busy-handler, this function should be invoked with the second (void *) in
+** the array as the only argument. If it returns non-zero, then the operation
+** should be retried. If it returns zero, the custom VFS should abandon the
+** current operation.
+**
+** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
+** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
+** to have SQLite generate a
+** temporary filename using the same algorithm that is followed to generate
+** temporary filenames for TEMP tables and other internal uses.  The
+** argument should be a char** which will be filled with the filename
+** written into memory obtained from [sqlite3_malloc()].  The caller should
+** invoke [sqlite3_free()] on the result to avoid a memory leak.
+**
+** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
+** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
+** maximum number of bytes that will be used for memory-mapped I/O.
+** The argument is a pointer to a value of type sqlite3_int64 that
+** is an advisory maximum number of bytes in the file to memory map.  The
+** pointer is overwritten with the old value.  The limit is not changed if
+** the value originally pointed to is negative, and so the current limit 
+** can be queried by passing in a pointer to a negative number.  This
+** file-control is used internally to implement [PRAGMA mmap_size].
+**
 ** </ul>
 */
 #define SQLITE_FCNTL_LOCKSTATE               1
@@ -852,6 +926,9 @@ struct sqlite3_io_methods {
 #define SQLITE_FCNTL_VFSNAME                12
 #define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
 #define SQLITE_FCNTL_PRAGMA                 14
+#define SQLITE_FCNTL_BUSYHANDLER            15
+#define SQLITE_FCNTL_TEMPFILENAME           16
+#define SQLITE_FCNTL_MMAP_SIZE              18
 
 /*
 ** CAPI3REF: Mutex Handle
@@ -1518,7 +1595,9 @@ struct sqlite3_mem_methods {
 ** page cache implementation into that object.)^ </dd>
 **
 ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
-** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
+** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
+** global [error log].
+** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
 ** function with a call signature of void(*)(void*,int,const char*), 
 ** and a pointer to void. ^If the function pointer is not NULL, it is
 ** invoked by [sqlite3_log()] to process each logging event.  ^If the
@@ -1548,10 +1627,54 @@ struct sqlite3_mem_methods {
 ** disabled. The default value may be changed by compiling with the
 ** [SQLITE_USE_URI] symbol defined.
 **
+** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
+** <dd> This option takes a single integer argument which is interpreted as
+** a boolean in order to enable or disable the use of covering indices for
+** full table scans in the query optimizer.  The default setting is determined
+** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
+** if that compile-time option is omitted.
+** The ability to disable the use of covering indices for full table scans
+** is because some incorrectly coded legacy applications might malfunction
+** malfunction when the optimization is enabled.  Providing the ability to
+** disable the optimization allows the older, buggy application code to work
+** without change even with newer versions of SQLite.
+**
 ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
 ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
 ** <dd> These options are obsolete and should not be used by new code.
 ** They are retained for backwards compatibility but are now no-ops.
+** </dd>
+**
+** [[SQLITE_CONFIG_SQLLOG]]
+** <dt>SQLITE_CONFIG_SQLLOG
+** <dd>This option is only available if sqlite is compiled with the
+** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
+** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
+** The second should be of type (void*). The callback is invoked by the library
+** in three separate circumstances, identified by the value passed as the
+** fourth parameter. If the fourth parameter is 0, then the database connection
+** passed as the second argument has just been opened. The third argument
+** points to a buffer containing the name of the main database file. If the
+** fourth parameter is 1, then the SQL statement that the third parameter
+** points to has just been executed. Or, if the fourth parameter is 2, then
+** the connection being passed as the second parameter is being closed. The
+** third parameter is passed NULL In this case.  An example of using this
+** configuration option can be seen in the "test_sqllog.c" source file in
+** the canonical SQLite source tree.</dd>
+**
+** [[SQLITE_CONFIG_MMAP_SIZE]]
+** <dt>SQLITE_CONFIG_MMAP_SIZE
+** <dd>SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
+** that are the default mmap size limit (the default setting for
+** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
+** The default setting can be overridden by each database connection using
+** either the [PRAGMA mmap_size] command, or by using the
+** [SQLITE_FCNTL_MMAP_SIZE] file control.  The maximum allowed mmap size
+** cannot be changed at run-time.  Nor may the maximum allowed mmap size
+** exceed the compile-time maximum mmap size set by the
+** [SQLITE_MAX_MMAP_SIZE] compile-time option.  
+** If either argument to this option is negative, then that argument is
+** changed to its compile-time default.
 ** </dl>
 */
 #define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
@@ -1573,6 +1696,9 @@ struct sqlite3_mem_methods {
 #define SQLITE_CONFIG_URI          17  /* int */
 #define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
 #define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
+#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
+#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
+#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
 
 /*
 ** CAPI3REF: Database Connection Configuration Options
@@ -2406,6 +2532,9 @@ SQLITE_API int sqlite3_set_authorizer(
 ** as each triggered subprogram is entered.  The callbacks for triggers
 ** contain a UTF-8 SQL comment that identifies the trigger.)^
 **
+** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
+** the length of [bound parameter] expansion in the output of sqlite3_trace().
+**
 ** ^The callback function registered by sqlite3_profile() is invoked
 ** as each SQL statement finishes.  ^The profile callback contains
 ** the original statement text and an estimate of wall-clock time
@@ -2431,9 +2560,10 @@ SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
 ** interface is to keep a GUI updated during a large query.
 **
 ** ^The parameter P is passed through as the only parameter to the 
-** callback function X.  ^The parameter N is the number of 
+** callback function X.  ^The parameter N is the approximate number of 
 ** [virtual machine instructions] that are evaluated between successive
-** invocations of the callback X.
+** invocations of the callback X.  ^If N is less than one then the progress
+** handler is disabled.
 **
 ** ^Only a single progress handler may be defined at one time per
 ** [database connection]; setting a new progress handler cancels the
@@ -2581,7 +2711,7 @@ SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 **     an error)^. 
 **     ^If "ro" is specified, then the database is opened for read-only 
 **     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 
-**     third argument to sqlite3_prepare_v2(). ^If the mode option is set to 
+**     third argument to sqlite3_open_v2(). ^If the mode option is set to 
 **     "rw", then the database is opened for read-write (but not create) 
 **     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 
 **     been set. ^Value "rwc" is equivalent to setting both 
@@ -2597,7 +2727,7 @@ SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 **     sqlite3_open_v2(). ^Setting the cache parameter to "private" is 
 **     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
 **     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
-**     a URI filename, its value overrides any behaviour requested by setting
+**     a URI filename, its value overrides any behavior requested by setting
 **     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
 ** </ul>
 **
@@ -2648,6 +2778,12 @@ SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 ** codepage is currently defined.  Filenames containing international
 ** characters must be converted to UTF-8 prior to passing them into
 ** sqlite3_open() or sqlite3_open_v2().
+**
+** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
+** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
+** features that require the use of temporary files may fail.
+**
+** See also: [sqlite3_temp_directory]
 */
 SQLITE_API int sqlite3_open(
   const char *filename,   /* Database filename (UTF-8) */
@@ -2727,6 +2863,11 @@ SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int
 ** However, the error string might be overwritten or deallocated by
 ** subsequent calls to other SQLite interface functions.)^
 **
+** ^The sqlite3_errstr() interface returns the English-language text
+** that describes the [result code], as UTF-8.
+** ^(Memory to hold the error message string is managed internally
+** and must not be freed by the application)^.
+**
 ** When the serialized [threading mode] is in use, it might be the
 ** case that a second error occurs on a separate thread in between
 ** the time of the first error and the call to these interfaces.
@@ -2745,6 +2886,7 @@ SQLITE_API int sqlite3_errcode(sqlite3 *db);
 SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
 SQLITE_API const char *sqlite3_errmsg(sqlite3*);
 SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
+SQLITE_API const char *sqlite3_errstr(int);
 
 /*
 ** CAPI3REF: SQL Statement Object
@@ -2932,7 +3074,8 @@ SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
 ** <li>
 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
-** statement and try to run it again.
+** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
+** retries will occur before sqlite3_step() gives up and returns an error.
 ** </li>
 **
 ** <li>
@@ -3136,12 +3279,18 @@ typedef struct sqlite3_context sqlite3_context;
 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
 **
 ** ^The third argument is the value to bind to the parameter.
+** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
+** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
+** is ignored and the end result is the same as sqlite3_bind_null().
 **
 ** ^(In those routines that have a fourth argument, its value is the
 ** number of bytes in the parameter.  To be clear: the value is the
 ** number of <u>bytes</u> in the value, not the number of characters.)^
-** ^If the fourth parameter is negative, the length of the string is
+** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
+** is negative, then the length of the string is
 ** the number of bytes up to the first zero terminator.
+** If the fourth parameter to sqlite3_bind_blob() is negative, then
+** the behavior is undefined.
 ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
 ** or sqlite3_bind_text16() then that parameter must be the byte offset
 ** where the NUL terminator would occur assuming the string were NUL
@@ -3900,7 +4049,8 @@ SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
 SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
 SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
 SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
-SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
+                      void*,sqlite3_int64);
 #endif
 
 /*
@@ -3980,14 +4130,17 @@ SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
 ** In those cases, sqlite3_aggregate_context() might be called for the
 ** first time from within xFinal().)^
 **
-** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
-** less than or equal to zero or if a memory allocate error occurs.
+** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 
+** when first called if N is less than or equal to zero or if a memory
+** allocate error occurs.
 **
 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
 ** determined by the N parameter on first successful call.  Changing the
 ** value of N in subsequent call to sqlite3_aggregate_context() within
 ** the same aggregate function instance will not resize the memory
-** allocation.)^
+** allocation.)^  Within the xFinal callback, it is customary to set
+** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 
+** pointless memory allocations occur.
 **
 ** ^SQLite automatically frees the memory allocated by 
 ** sqlite3_aggregate_context() when the aggregate query concludes.
@@ -4030,41 +4183,49 @@ SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
 /*
 ** CAPI3REF: Function Auxiliary Data
 **
-** The following two functions may be used by scalar SQL functions to
+** These functions may be used by (non-aggregate) SQL functions to
 ** associate metadata with argument values. If the same value is passed to
 ** multiple invocations of the same SQL function during query execution, under
-** some circumstances the associated metadata may be preserved. This may
-** be used, for example, to add a regular-expression matching scalar
-** function. The compiled version of the regular expression is stored as
-** metadata associated with the SQL value passed as the regular expression
-** pattern.  The compiled regular expression can be reused on multiple
-** invocations of the same function so that the original pattern string
-** does not need to be recompiled on each invocation.
+** some circumstances the associated metadata may be preserved.  An example
+** of where this might be useful is in a regular-expression matching
+** function. The compiled version of the regular expression can be stored as
+** metadata associated with the pattern string.  
+** Then as long as the pattern string remains the same,
+** the compiled regular expression can be reused on multiple
+** invocations of the same function.
 **
 ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
 ** associated by the sqlite3_set_auxdata() function with the Nth argument
-** value to the application-defined function. ^If no metadata has been ever
-** been set for the Nth argument of the function, or if the corresponding
-** function parameter has changed since the meta-data was set,
-** then sqlite3_get_auxdata() returns a NULL pointer.
+** value to the application-defined function. ^If there is no metadata
+** associated with the function argument, this sqlite3_get_auxdata() interface
+** returns a NULL pointer.
 **
-** ^The sqlite3_set_auxdata() interface saves the metadata
-** pointed to by its 3rd parameter as the metadata for the N-th
-** argument of the application-defined function.  Subsequent
-** calls to sqlite3_get_auxdata() might return this data, if it has
-** not been destroyed.
-** ^If it is not NULL, SQLite will invoke the destructor
-** function given by the 4th parameter to sqlite3_set_auxdata() on
-** the metadata when the corresponding function parameter changes
-** or when the SQL statement completes, whichever comes first.
+** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
+** argument of the application-defined function.  ^Subsequent
+** calls to sqlite3_get_auxdata(C,N) return P from the most recent
+** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
+** NULL if the metadata has been discarded.
+** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
+** SQLite will invoke the destructor function X with parameter P exactly
+** once, when the metadata is discarded.
+** SQLite is free to discard the metadata at any time, including: <ul>
+** <li> when the corresponding function parameter changes, or
+** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
+**      SQL statement, or
+** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or
+** <li> during the original sqlite3_set_auxdata() call when a memory 
+**      allocation error occurs. </ul>)^
 **
-** SQLite is free to call the destructor and drop metadata on any
-** parameter of any function at any time.  ^The only guarantee is that
-** the destructor will be called before the metadata is dropped.
+** Note the last bullet in particular.  The destructor X in 
+** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
+** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
+** should be called near the end of the function implementation and the
+** function implementation should not make any use of P after
+** sqlite3_set_auxdata() has been called.
 **
 ** ^(In practice, metadata is preserved between function calls for
-** expressions that are constant at compile time. This includes literal
-** values and [parameters].)^
+** function parameters that are compile-time constants, including literal
+** values and [parameters] and expressions composed from the same.)^
 **
 ** These routines must be called from the same thread in which
 ** the SQL function is running.
@@ -4085,7 +4246,7 @@ SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(voi
 ** the content before returning.
 **
 ** The typedef is necessary to work around problems in certain
-** C++ compilers.  See ticket #2191.
+** C++ compilers.
 */
 typedef void (*sqlite3_destructor_type)(void*);
 #define SQLITE_STATIC      ((sqlite3_destructor_type)0)
@@ -4138,11 +4299,11 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
 **
-** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
-** indicating that a string or BLOB is too long to represent.
+** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
+** error indicating that a string or BLOB is too long to represent.
 **
-** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
-** indicating that a memory allocation failed.
+** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
+** error indicating that a memory allocation failed.
 **
 ** ^The sqlite3_result_int() interface sets the return value
 ** of the application-defined function to be the 32-bit signed integer
@@ -4369,6 +4530,11 @@ SQLITE_API int sqlite3_key(
   sqlite3 *db,                   /* Database to be rekeyed */
   const void *pKey, int nKey     /* The key */
 );
+SQLITE_API int sqlite3_key_v2(
+  sqlite3 *db,                   /* Database to be rekeyed */
+  const char *zDbName,           /* Name of the database */
+  const void *pKey, int nKey     /* The key */
+);
 
 /*
 ** Change the key on an open database.  If the current database is not
@@ -4382,6 +4548,11 @@ SQLITE_API int sqlite3_rekey(
   sqlite3 *db,                   /* Database to be rekeyed */
   const void *pKey, int nKey     /* The new key */
 );
+SQLITE_API int sqlite3_rekey_v2(
+  sqlite3 *db,                   /* Database to be rekeyed */
+  const char *zDbName,           /* Name of the database */
+  const void *pKey, int nKey     /* The new key */
+);
 
 /*
 ** Specify the activation key for a SEE database.  Unless 
@@ -4449,6 +4620,21 @@ SQLITE_API int sqlite3_sleep(int);
 ** Hence, if this variable is modified directly, either it should be
 ** made NULL or made to point to memory obtained from [sqlite3_malloc]
 ** or else the use of the [temp_store_directory pragma] should be avoided.
+**
+** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
+** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
+** features that require the use of temporary files may fail.  Here is an
+** example of how to do this using C++ with the Windows Runtime:
+**
+** <blockquote><pre>
+** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
+** &nbsp;     TemporaryFolder->Path->Data();
+** char zPathBuf&#91;MAX_PATH + 1&#93;;
+** memset(zPathBuf, 0, sizeof(zPathBuf));
+** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
+** &nbsp;     NULL, NULL);
+** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
+** </pre></blockquote>
 */
 SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory;
 
@@ -4689,6 +4875,9 @@ SQLITE_API void *sqlite3_update_hook(
 ** future releases of SQLite.  Applications that care about shared
 ** cache setting should set it explicitly.
 **
+** This interface is threadsafe on processors where writing a
+** 32-bit integer is atomic.
+**
 ** See Also:  [SQLite Shared-Cache Mode]
 */
 SQLITE_API int sqlite3_enable_shared_cache(int);
@@ -4866,11 +5055,20 @@ SQLITE_API int sqlite3_table_column_metadata(
 ** ^This interface loads an SQLite extension library from the named file.
 **
 ** ^The sqlite3_load_extension() interface attempts to load an
-** SQLite extension library contained in the file zFile.
+** [SQLite extension] library contained in the file zFile.  If
+** the file cannot be loaded directly, attempts are made to load
+** with various operating-system specific extensions added.
+** So for example, if "samplelib" cannot be loaded, then names like
+** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
+** be tried also.
 **
 ** ^The entry point is zProc.
-** ^zProc may be 0, in which case the name of the entry point
-** defaults to "sqlite3_extension_init".
+** ^(zProc may be 0, in which case SQLite will try to come up with an
+** entry point name on its own.  It first tries "sqlite3_extension_init".
+** If that does not work, it constructs a name "sqlite3_X_init" where the
+** X is consists of the lower-case equivalent of all ASCII alphabetic
+** characters in the filename from the last "/" to the first following
+** "." and omitting any initial "lib".)^
 ** ^The sqlite3_load_extension() interface returns
 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
 ** ^If an error occurs and pzErrMsg is not 0, then the
@@ -4896,11 +5094,11 @@ SQLITE_API int sqlite3_load_extension(
 ** CAPI3REF: Enable Or Disable Extension Loading
 **
 ** ^So as not to open security holes in older applications that are
-** unprepared to deal with extension loading, and as a means of disabling
-** extension loading while evaluating user-entered SQL, the following API
+** unprepared to deal with [extension loading], and as a means of disabling
+** [extension loading] while evaluating user-entered SQL, the following API
 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
 **
-** ^Extension loading is off by default. See ticket #1863.
+** ^Extension loading is off by default.
 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
 ** to turn extension loading on and call it with onoff==0 to turn
 ** it back off again.
@@ -4912,7 +5110,7 @@ SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 **
 ** ^This interface causes the xEntryPoint() function to be invoked for
 ** each new [database connection] that is created.  The idea here is that
-** xEntryPoint() is the entry point for a statically linked SQLite extension
+** xEntryPoint() is the entry point for a statically linked [SQLite extension]
 ** that is to be automatically loaded into all new database connections.
 **
 ** ^(Even though the function prototype shows that xEntryPoint() takes
@@ -4940,10 +5138,23 @@ SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 ** on the list of automatic extensions is a harmless no-op. ^No entry point
 ** will be called more than once for each database connection that is opened.
 **
-** See also: [sqlite3_reset_auto_extension()].
+** See also: [sqlite3_reset_auto_extension()]
+** and [sqlite3_cancel_auto_extension()]
 */
 SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
 
+/*
+** CAPI3REF: Cancel Automatic Extension Loading
+**
+** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
+** initialization routine X that was registered using a prior call to
+** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
+** routine returns 1 if initialization routine X was successfully 
+** unregistered and it returns 0 if X was not on the list of initialization
+** routines.
+*/
+SQLITE_API int sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
+
 /*
 ** CAPI3REF: Reset Automatic Extension Loading
 **
@@ -5494,7 +5705,6 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** implementations are available in the SQLite core:
 **
 ** <ul>
-** <li>   SQLITE_MUTEX_OS2
 ** <li>   SQLITE_MUTEX_PTHREADS
 ** <li>   SQLITE_MUTEX_W32
 ** <li>   SQLITE_MUTEX_NOOP
@@ -5502,9 +5712,9 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 **
 ** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
 ** that does no real locking and is appropriate for use in
-** a single-threaded application.  ^The SQLITE_MUTEX_OS2,
-** SQLITE_MUTEX_PTHREADS, and SQLITE_MUTEX_W32 implementations
-** are appropriate for use on OS/2, Unix, and Windows.
+** a single-threaded application.  ^The SQLITE_MUTEX_PTHREADS and
+** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
+** and Windows.
 **
 ** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
@@ -6057,6 +6267,12 @@ SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int r
 ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
 ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
 ** </dd>
+**
+** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
+** <dd>This parameter returns zero for the current value if and only if
+** all foreign key constraints (deferred or immediate) have been
+** resolved.)^  ^The highwater mark is always 0.
+** </dd>
 ** </dl>
 */
 #define SQLITE_DBSTATUS_LOOKASIDE_USED       0
@@ -6069,7 +6285,8 @@ SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int r
 #define SQLITE_DBSTATUS_CACHE_HIT            7
 #define SQLITE_DBSTATUS_CACHE_MISS           8
 #define SQLITE_DBSTATUS_CACHE_WRITE          9
-#define SQLITE_DBSTATUS_MAX                  9   /* Largest defined DBSTATUS */
+#define SQLITE_DBSTATUS_DEFERRED_FKS        10
+#define SQLITE_DBSTATUS_MAX                 10   /* Largest defined DBSTATUS */
 
 
 /*
@@ -6123,11 +6340,21 @@ SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
 ** A non-zero value in this counter may indicate an opportunity to
 ** improvement performance by adding permanent indices that do not
 ** need to be reinitialized each time the statement is run.</dd>
+**
+** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
+** <dd>^This is the number of virtual machine operations executed
+** by the prepared statement if that number is less than or equal
+** to 2147483647.  The number of virtual machine operations can be 
+** used as a proxy for the total work done by the prepared statement.
+** If the number of virtual machine operations exceeds 2147483647
+** then the value returned by this statement status code is undefined.
+** </dd>
 ** </dl>
 */
 #define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
 #define SQLITE_STMTSTATUS_SORT              2
 #define SQLITE_STMTSTATUS_AUTOINDEX         3
+#define SQLITE_STMTSTATUS_VM_STEP           4
 
 /*
 ** CAPI3REF: Custom Page Cache Object
@@ -6264,7 +6491,7 @@ struct sqlite3_pcache_page {
 ** parameter to help it determined what action to take:
 **
 ** <table border=1 width=85% align=center>
-** <tr><th> createFlag <th> Behaviour when page is not already in cache
+** <tr><th> createFlag <th> Behavior when page is not already in cache
 ** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
 ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
 **                 Otherwise return NULL.
@@ -6693,10 +6920,25 @@ SQLITE_API int sqlite3_unlock_notify(
 SQLITE_API int sqlite3_stricmp(const char *, const char *);
 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
 
+/*
+** CAPI3REF: String Globbing
+*
+** ^The [sqlite3_strglob(P,X)] interface returns zero if string X matches
+** the glob pattern P, and it returns non-zero if string X does not match
+** the glob pattern P.  ^The definition of glob pattern matching used in
+** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
+** SQL dialect used by SQLite.  ^The sqlite3_strglob(P,X) function is case
+** sensitive.
+**
+** Note that this routine returns zero on a match and non-zero if the strings
+** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
+*/
+SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
+
 /*
 ** CAPI3REF: Error Logging Interface
 **
-** ^The [sqlite3_log()] interface writes a message into the error log
+** ^The [sqlite3_log()] interface writes a message into the [error log]
 ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
 ** ^If logging is enabled, the zFormat string and subsequent arguments are
 ** used with [sqlite3_snprintf()] to generate the final output string.
@@ -6991,7 +7233,7 @@ SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
 #ifdef __cplusplus
 }  /* End of the 'extern "C"' block */
 #endif
-#endif
+#endif /* _SQLITE3_H_ */
 
 /*
 ** 2010 August 30
diff --git a/src/Navaids/sqlite3.c b/3rdparty/sqlite3/sqlite3.c
similarity index 90%
rename from src/Navaids/sqlite3.c
rename to 3rdparty/sqlite3/sqlite3.c
index f69816e2a..9657356ee 100644
--- a/src/Navaids/sqlite3.c
+++ b/3rdparty/sqlite3/sqlite3.c
@@ -1,6 +1,6 @@
 /******************************************************************************
 ** This file is an amalgamation of many separate C source files from SQLite
-** version 3.7.13.  By combining all the individual C code files into this 
+** version 3.8.0.2.  By combining all the individual C code files into this 
 ** single large file, the entire code can be compiled as a single translation
 ** unit.  This allows many compilers to do optimizations that would not be
 ** possible if the files were compiled separately.  Performance improvements
@@ -306,6 +306,10 @@
 # define _GNU_SOURCE
 #endif
 
+#if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
+# define _BSD_SOURCE
+#endif
+
 /*
 ** Include standard header files as necessary
 */
@@ -350,7 +354,7 @@
 ** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
 ** 0 means mutexes are permanently disable and the library is never
 ** threadsafe.  1 means the library is serialized which is the highest
-** level of threadsafety.  2 means the libary is multithreaded - multiple
+** level of threadsafety.  2 means the library is multithreaded - multiple
 ** threads can use SQLite as long as no two threads try to use the same
 ** database connection at the same time.
 **
@@ -358,11 +362,11 @@
 ** We support that for legacy.
 */
 #if !defined(SQLITE_THREADSAFE)
-#if defined(THREADSAFE)
-# define SQLITE_THREADSAFE THREADSAFE
-#else
-# define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
-#endif
+# if defined(THREADSAFE)
+#   define SQLITE_THREADSAFE THREADSAFE
+# else
+#   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
+# endif
 #endif
 
 /*
@@ -389,6 +393,7 @@
 **
 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
+**     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
 **
 ** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
@@ -396,17 +401,22 @@
 ** will cause HeapValidate to be called.  If heap validation should fail, an
 ** assertion will be triggered.
 **
-** (Historical note:  There used to be several other options, but we've
-** pared it down to just these three.)
-**
 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
 ** the default.
 */
-#if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_WIN32_MALLOC)+defined(SQLITE_MEMDEBUG)>1
-# error "At most one of the following compile-time configuration options\
- is allows: SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG"
+#if defined(SQLITE_SYSTEM_MALLOC) \
+  + defined(SQLITE_WIN32_MALLOC) \
+  + defined(SQLITE_ZERO_MALLOC) \
+  + defined(SQLITE_MEMDEBUG)>1
+# error "Two or more of the following compile-time configuration options\
+ are defined but at most one is allowed:\
+ SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
+ SQLITE_ZERO_MALLOC"
 #endif
-#if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_WIN32_MALLOC)+defined(SQLITE_MEMDEBUG)==0
+#if defined(SQLITE_SYSTEM_MALLOC) \
+  + defined(SQLITE_WIN32_MALLOC) \
+  + defined(SQLITE_ZERO_MALLOC) \
+  + defined(SQLITE_MEMDEBUG)==0
 # define SQLITE_SYSTEM_MALLOC 1
 #endif
 
@@ -420,26 +430,12 @@
 
 /*
 ** We need to define _XOPEN_SOURCE as follows in order to enable
-** recursive mutexes on most Unix systems.  But Mac OS X is different.
-** The _XOPEN_SOURCE define causes problems for Mac OS X we are told,
-** so it is omitted there.  See ticket #2673.
-**
-** Later we learn that _XOPEN_SOURCE is poorly or incorrectly
-** implemented on some systems.  So we avoid defining it at all
-** if it is already defined or if it is unneeded because we are
-** not doing a threadsafe build.  Ticket #2681.
-**
-** See also ticket #2741.
+** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
+** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
+** it.
 */
-#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__) && SQLITE_THREADSAFE
-#  define _XOPEN_SOURCE 500  /* Needed to enable pthread recursive mutexes */
-#endif
-
-/*
-** The TCL headers are only needed when compiling the TCL bindings.
-*/
-#if defined(SQLITE_TCL) || defined(TCLSH)
-# include <tcl.h>
+#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
+#  define _XOPEN_SOURCE 600
 #endif
 
 /*
@@ -447,8 +443,8 @@
 ** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
 ** make it true by defining or undefining NDEBUG.
 **
-** Setting NDEBUG makes the code smaller and run faster by disabling the
-** number assert() statements in the code.  So we want the default action
+** Setting NDEBUG makes the code smaller and faster by disabling the
+** assert() statements in the code.  So we want the default action
 ** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
 ** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
 ** feature.
@@ -518,7 +514,7 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 ** In other words, ALWAYS and NEVER are added for defensive code.
 **
 ** When doing coverage testing ALWAYS and NEVER are hard-coded to
-** be true and false so that the unreachable code then specify will
+** be true and false so that the unreachable code they specify will
 ** not be counted as untested code.
 */
 #if defined(SQLITE_COVERAGE_TEST)
@@ -542,16 +538,12 @@ SQLITE_PRIVATE   void sqlite3Coverage(int);
 /*
 ** The macro unlikely() is a hint that surrounds a boolean
 ** expression that is usually false.  Macro likely() surrounds
-** a boolean expression that is usually true.  GCC is able to
-** use these hints to generate better code, sometimes.
+** a boolean expression that is usually true.  These hints could,
+** in theory, be used by the compiler to generate better code, but
+** currently they are just comments for human readers.
 */
-#if defined(__GNUC__) && 0
-# define likely(X)    __builtin_expect((X),1)
-# define unlikely(X)  __builtin_expect((X),0)
-#else
-# define likely(X)    !!(X)
-# define unlikely(X)  !!(X)
-#endif
+#define likely(X)    (X)
+#define unlikely(X)  (X)
 
 /************** Include sqlite3.h in the middle of sqliteInt.h ***************/
 /************** Begin file sqlite3.h *****************************************/
@@ -664,9 +656,9 @@ extern "C" {
 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
 ** [sqlite_version()] and [sqlite_source_id()].
 */
-#define SQLITE_VERSION        "3.7.13"
-#define SQLITE_VERSION_NUMBER 3007013
-#define SQLITE_SOURCE_ID      "2012-06-11 02:05:22 f5b5a13f7394dc143aa136f1d4faba6839eaa6dc"
+#define SQLITE_VERSION        "3.8.0.2"
+#define SQLITE_VERSION_NUMBER 3008000
+#define SQLITE_SOURCE_ID      "2013-09-03 17:11:13 7dd4968f235d6e1ca9547cda9cf3bd570e1609ef"
 
 /*
 ** CAPI3REF: Run-Time Library Version Numbers
@@ -776,7 +768,8 @@ SQLITE_API int sqlite3_threadsafe(void);
 ** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
 ** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]
-** is its destructor.  There are many other interfaces (such as
+** and [sqlite3_close_v2()] are its destructors.  There are many other
+** interfaces (such as
 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
 ** [sqlite3_busy_timeout()] to name but three) that are methods on an
 ** sqlite3 object.
@@ -823,28 +816,46 @@ typedef sqlite_uint64 sqlite3_uint64;
 /*
 ** CAPI3REF: Closing A Database Connection
 **
-** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
-** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
-** successfully destroyed and all associated resources are deallocated.
+** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors
+** for the [sqlite3] object.
+** ^Calls to sqlite3_close() and sqlite3_close_v2() return SQLITE_OK if
+** the [sqlite3] object is successfully destroyed and all associated
+** resources are deallocated.
 **
-** Applications must [sqlite3_finalize | finalize] all [prepared statements]
-** and [sqlite3_blob_close | close] all [BLOB handles] associated with
-** the [sqlite3] object prior to attempting to close the object.  ^If
-** sqlite3_close() is called on a [database connection] that still has
-** outstanding [prepared statements] or [BLOB handles], then it returns
-** SQLITE_BUSY.
+** ^If the database connection is associated with unfinalized prepared
+** statements or unfinished sqlite3_backup objects then sqlite3_close()
+** will leave the database connection open and return [SQLITE_BUSY].
+** ^If sqlite3_close_v2() is called with unfinalized prepared statements
+** and unfinished sqlite3_backups, then the database connection becomes
+** an unusable "zombie" which will automatically be deallocated when the
+** last prepared statement is finalized or the last sqlite3_backup is
+** finished.  The sqlite3_close_v2() interface is intended for use with
+** host languages that are garbage collected, and where the order in which
+** destructors are called is arbitrary.
 **
-** ^If [sqlite3_close()] is invoked while a transaction is open,
+** Applications should [sqlite3_finalize | finalize] all [prepared statements],
+** [sqlite3_blob_close | close] all [BLOB handles], and 
+** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated
+** with the [sqlite3] object prior to attempting to close the object.  ^If
+** sqlite3_close_v2() is called on a [database connection] that still has
+** outstanding [prepared statements], [BLOB handles], and/or
+** [sqlite3_backup] objects then it returns SQLITE_OK but the deallocation
+** of resources is deferred until all [prepared statements], [BLOB handles],
+** and [sqlite3_backup] objects are also destroyed.
+**
+** ^If an [sqlite3] object is destroyed while a transaction is open,
 ** the transaction is automatically rolled back.
 **
-** The C parameter to [sqlite3_close(C)] must be either a NULL
+** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]
+** must be either a NULL
 ** pointer or an [sqlite3] object pointer obtained
 ** from [sqlite3_open()], [sqlite3_open16()], or
 ** [sqlite3_open_v2()], and not previously closed.
-** ^Calling sqlite3_close() with a NULL pointer argument is a 
-** harmless no-op.
+** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer
+** argument is a harmless no-op.
 */
-SQLITE_API int sqlite3_close(sqlite3 *);
+SQLITE_API int sqlite3_close(sqlite3*);
+SQLITE_API int sqlite3_close_v2(sqlite3*);
 
 /*
 ** The type for a callback function.
@@ -963,6 +974,8 @@ SQLITE_API int sqlite3_exec(
 #define SQLITE_FORMAT      24   /* Auxiliary database format error */
 #define SQLITE_RANGE       25   /* 2nd parameter to sqlite3_bind out of range */
 #define SQLITE_NOTADB      26   /* File opened that is not a database file */
+#define SQLITE_NOTICE      27   /* Notifications from sqlite3_log() */
+#define SQLITE_WARNING     28   /* Warnings from sqlite3_log() */
 #define SQLITE_ROW         100  /* sqlite3_step() has another row ready */
 #define SQLITE_DONE        101  /* sqlite3_step() has finished executing */
 /* end-of-error-codes */
@@ -1012,14 +1025,32 @@ SQLITE_API int sqlite3_exec(
 #define SQLITE_IOERR_SHMLOCK           (SQLITE_IOERR | (20<<8))
 #define SQLITE_IOERR_SHMMAP            (SQLITE_IOERR | (21<<8))
 #define SQLITE_IOERR_SEEK              (SQLITE_IOERR | (22<<8))
+#define SQLITE_IOERR_DELETE_NOENT      (SQLITE_IOERR | (23<<8))
+#define SQLITE_IOERR_MMAP              (SQLITE_IOERR | (24<<8))
+#define SQLITE_IOERR_GETTEMPPATH       (SQLITE_IOERR | (25<<8))
 #define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
 #define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
+#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
 #define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
 #define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
+#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
 #define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
 #define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
 #define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
+#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
 #define SQLITE_ABORT_ROLLBACK          (SQLITE_ABORT | (2<<8))
+#define SQLITE_CONSTRAINT_CHECK        (SQLITE_CONSTRAINT | (1<<8))
+#define SQLITE_CONSTRAINT_COMMITHOOK   (SQLITE_CONSTRAINT | (2<<8))
+#define SQLITE_CONSTRAINT_FOREIGNKEY   (SQLITE_CONSTRAINT | (3<<8))
+#define SQLITE_CONSTRAINT_FUNCTION     (SQLITE_CONSTRAINT | (4<<8))
+#define SQLITE_CONSTRAINT_NOTNULL      (SQLITE_CONSTRAINT | (5<<8))
+#define SQLITE_CONSTRAINT_PRIMARYKEY   (SQLITE_CONSTRAINT | (6<<8))
+#define SQLITE_CONSTRAINT_TRIGGER      (SQLITE_CONSTRAINT | (7<<8))
+#define SQLITE_CONSTRAINT_UNIQUE       (SQLITE_CONSTRAINT | (8<<8))
+#define SQLITE_CONSTRAINT_VTAB         (SQLITE_CONSTRAINT | (9<<8))
+#define SQLITE_NOTICE_RECOVER_WAL      (SQLITE_NOTICE | (1<<8))
+#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))
+#define SQLITE_WARNING_AUTOINDEX       (SQLITE_WARNING | (1<<8))
 
 /*
 ** CAPI3REF: Flags For File Open Operations
@@ -1055,7 +1086,7 @@ SQLITE_API int sqlite3_exec(
 ** CAPI3REF: Device Characteristics
 **
 ** The xDeviceCharacteristics method of the [sqlite3_io_methods]
-** object returns an integer which is a vector of the these
+** object returns an integer which is a vector of these
 ** bit values expressing I/O characteristics of the mass storage
 ** device that holds the file that the [sqlite3_io_methods]
 ** refers to.
@@ -1259,6 +1290,9 @@ struct sqlite3_io_methods {
   void (*xShmBarrier)(sqlite3_file*);
   int (*xShmUnmap)(sqlite3_file*, int deleteFlag);
   /* Methods above are valid for version 2 */
+  int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp);
+  int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p);
+  /* Methods above are valid for version 3 */
   /* Additional methods may be added in future releases */
 };
 
@@ -1393,6 +1427,38 @@ struct sqlite3_io_methods {
 ** compilation of the PRAGMA fails with an error.  ^The [SQLITE_FCNTL_PRAGMA]
 ** file control occurs at the beginning of pragma statement analysis and so
 ** it is able to override built-in [PRAGMA] statements.
+**
+** <li>[[SQLITE_FCNTL_BUSYHANDLER]]
+** ^The [SQLITE_FCNTL_BUSYHANDLER]
+** file-control may be invoked by SQLite on the database file handle
+** shortly after it is opened in order to provide a custom VFS with access
+** to the connections busy-handler callback. The argument is of type (void **)
+** - an array of two (void *) values. The first (void *) actually points
+** to a function of type (int (*)(void *)). In order to invoke the connections
+** busy-handler, this function should be invoked with the second (void *) in
+** the array as the only argument. If it returns non-zero, then the operation
+** should be retried. If it returns zero, the custom VFS should abandon the
+** current operation.
+**
+** <li>[[SQLITE_FCNTL_TEMPFILENAME]]
+** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control
+** to have SQLite generate a
+** temporary filename using the same algorithm that is followed to generate
+** temporary filenames for TEMP tables and other internal uses.  The
+** argument should be a char** which will be filled with the filename
+** written into memory obtained from [sqlite3_malloc()].  The caller should
+** invoke [sqlite3_free()] on the result to avoid a memory leak.
+**
+** <li>[[SQLITE_FCNTL_MMAP_SIZE]]
+** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the
+** maximum number of bytes that will be used for memory-mapped I/O.
+** The argument is a pointer to a value of type sqlite3_int64 that
+** is an advisory maximum number of bytes in the file to memory map.  The
+** pointer is overwritten with the old value.  The limit is not changed if
+** the value originally pointed to is negative, and so the current limit 
+** can be queried by passing in a pointer to a negative number.  This
+** file-control is used internally to implement [PRAGMA mmap_size].
+**
 ** </ul>
 */
 #define SQLITE_FCNTL_LOCKSTATE               1
@@ -1409,6 +1475,9 @@ struct sqlite3_io_methods {
 #define SQLITE_FCNTL_VFSNAME                12
 #define SQLITE_FCNTL_POWERSAFE_OVERWRITE    13
 #define SQLITE_FCNTL_PRAGMA                 14
+#define SQLITE_FCNTL_BUSYHANDLER            15
+#define SQLITE_FCNTL_TEMPFILENAME           16
+#define SQLITE_FCNTL_MMAP_SIZE              18
 
 /*
 ** CAPI3REF: Mutex Handle
@@ -2075,7 +2144,9 @@ struct sqlite3_mem_methods {
 ** page cache implementation into that object.)^ </dd>
 **
 ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>
-** <dd> ^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
+** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite
+** global [error log].
+** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a
 ** function with a call signature of void(*)(void*,int,const char*), 
 ** and a pointer to void. ^If the function pointer is not NULL, it is
 ** invoked by [sqlite3_log()] to process each logging event.  ^If the
@@ -2105,10 +2176,54 @@ struct sqlite3_mem_methods {
 ** disabled. The default value may be changed by compiling with the
 ** [SQLITE_USE_URI] symbol defined.
 **
+** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN
+** <dd> This option takes a single integer argument which is interpreted as
+** a boolean in order to enable or disable the use of covering indices for
+** full table scans in the query optimizer.  The default setting is determined
+** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"
+** if that compile-time option is omitted.
+** The ability to disable the use of covering indices for full table scans
+** is because some incorrectly coded legacy applications might malfunction
+** malfunction when the optimization is enabled.  Providing the ability to
+** disable the optimization allows the older, buggy application code to work
+** without change even with newer versions of SQLite.
+**
 ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]
 ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE
 ** <dd> These options are obsolete and should not be used by new code.
 ** They are retained for backwards compatibility but are now no-ops.
+** </dd>
+**
+** [[SQLITE_CONFIG_SQLLOG]]
+** <dt>SQLITE_CONFIG_SQLLOG
+** <dd>This option is only available if sqlite is compiled with the
+** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should
+** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).
+** The second should be of type (void*). The callback is invoked by the library
+** in three separate circumstances, identified by the value passed as the
+** fourth parameter. If the fourth parameter is 0, then the database connection
+** passed as the second argument has just been opened. The third argument
+** points to a buffer containing the name of the main database file. If the
+** fourth parameter is 1, then the SQL statement that the third parameter
+** points to has just been executed. Or, if the fourth parameter is 2, then
+** the connection being passed as the second parameter is being closed. The
+** third parameter is passed NULL In this case.  An example of using this
+** configuration option can be seen in the "test_sqllog.c" source file in
+** the canonical SQLite source tree.</dd>
+**
+** [[SQLITE_CONFIG_MMAP_SIZE]]
+** <dt>SQLITE_CONFIG_MMAP_SIZE
+** <dd>SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values
+** that are the default mmap size limit (the default setting for
+** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.
+** The default setting can be overridden by each database connection using
+** either the [PRAGMA mmap_size] command, or by using the
+** [SQLITE_FCNTL_MMAP_SIZE] file control.  The maximum allowed mmap size
+** cannot be changed at run-time.  Nor may the maximum allowed mmap size
+** exceed the compile-time maximum mmap size set by the
+** [SQLITE_MAX_MMAP_SIZE] compile-time option.  
+** If either argument to this option is negative, then that argument is
+** changed to its compile-time default.
 ** </dl>
 */
 #define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
@@ -2130,6 +2245,9 @@ struct sqlite3_mem_methods {
 #define SQLITE_CONFIG_URI          17  /* int */
 #define SQLITE_CONFIG_PCACHE2      18  /* sqlite3_pcache_methods2* */
 #define SQLITE_CONFIG_GETPCACHE2   19  /* sqlite3_pcache_methods2* */
+#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20  /* int */
+#define SQLITE_CONFIG_SQLLOG       21  /* xSqllog, void* */
+#define SQLITE_CONFIG_MMAP_SIZE    22  /* sqlite3_int64, sqlite3_int64 */
 
 /*
 ** CAPI3REF: Database Connection Configuration Options
@@ -2963,6 +3081,9 @@ SQLITE_API int sqlite3_set_authorizer(
 ** as each triggered subprogram is entered.  The callbacks for triggers
 ** contain a UTF-8 SQL comment that identifies the trigger.)^
 **
+** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit
+** the length of [bound parameter] expansion in the output of sqlite3_trace().
+**
 ** ^The callback function registered by sqlite3_profile() is invoked
 ** as each SQL statement finishes.  ^The profile callback contains
 ** the original statement text and an estimate of wall-clock time
@@ -2988,9 +3109,10 @@ SQLITE_API SQLITE_EXPERIMENTAL void *sqlite3_profile(sqlite3*,
 ** interface is to keep a GUI updated during a large query.
 **
 ** ^The parameter P is passed through as the only parameter to the 
-** callback function X.  ^The parameter N is the number of 
+** callback function X.  ^The parameter N is the approximate number of 
 ** [virtual machine instructions] that are evaluated between successive
-** invocations of the callback X.
+** invocations of the callback X.  ^If N is less than one then the progress
+** handler is disabled.
 **
 ** ^Only a single progress handler may be defined at one time per
 ** [database connection]; setting a new progress handler cancels the
@@ -3138,7 +3260,7 @@ SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 **     an error)^. 
 **     ^If "ro" is specified, then the database is opened for read-only 
 **     access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 
-**     third argument to sqlite3_prepare_v2(). ^If the mode option is set to 
+**     third argument to sqlite3_open_v2(). ^If the mode option is set to 
 **     "rw", then the database is opened for read-write (but not create) 
 **     access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 
 **     been set. ^Value "rwc" is equivalent to setting both 
@@ -3154,7 +3276,7 @@ SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 **     sqlite3_open_v2(). ^Setting the cache parameter to "private" is 
 **     equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.
 **     ^If sqlite3_open_v2() is used and the "cache" parameter is present in
-**     a URI filename, its value overrides any behaviour requested by setting
+**     a URI filename, its value overrides any behavior requested by setting
 **     SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.
 ** </ul>
 **
@@ -3205,6 +3327,12 @@ SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*);
 ** codepage is currently defined.  Filenames containing international
 ** characters must be converted to UTF-8 prior to passing them into
 ** sqlite3_open() or sqlite3_open_v2().
+**
+** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
+** prior to calling sqlite3_open() or sqlite3_open_v2().  Otherwise, various
+** features that require the use of temporary files may fail.
+**
+** See also: [sqlite3_temp_directory]
 */
 SQLITE_API int sqlite3_open(
   const char *filename,   /* Database filename (UTF-8) */
@@ -3284,6 +3412,11 @@ SQLITE_API sqlite3_int64 sqlite3_uri_int64(const char*, const char*, sqlite3_int
 ** However, the error string might be overwritten or deallocated by
 ** subsequent calls to other SQLite interface functions.)^
 **
+** ^The sqlite3_errstr() interface returns the English-language text
+** that describes the [result code], as UTF-8.
+** ^(Memory to hold the error message string is managed internally
+** and must not be freed by the application)^.
+**
 ** When the serialized [threading mode] is in use, it might be the
 ** case that a second error occurs on a separate thread in between
 ** the time of the first error and the call to these interfaces.
@@ -3302,6 +3435,7 @@ SQLITE_API int sqlite3_errcode(sqlite3 *db);
 SQLITE_API int sqlite3_extended_errcode(sqlite3 *db);
 SQLITE_API const char *sqlite3_errmsg(sqlite3*);
 SQLITE_API const void *sqlite3_errmsg16(sqlite3*);
+SQLITE_API const char *sqlite3_errstr(int);
 
 /*
 ** CAPI3REF: SQL Statement Object
@@ -3489,7 +3623,8 @@ SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal);
 ** <li>
 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it
 ** always used to do, [sqlite3_step()] will automatically recompile the SQL
-** statement and try to run it again.
+** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]
+** retries will occur before sqlite3_step() gives up and returns an error.
 ** </li>
 **
 ** <li>
@@ -3693,12 +3828,18 @@ typedef struct sqlite3_context sqlite3_context;
 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
 **
 ** ^The third argument is the value to bind to the parameter.
+** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()
+** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter
+** is ignored and the end result is the same as sqlite3_bind_null().
 **
 ** ^(In those routines that have a fourth argument, its value is the
 ** number of bytes in the parameter.  To be clear: the value is the
 ** number of <u>bytes</u> in the value, not the number of characters.)^
-** ^If the fourth parameter is negative, the length of the string is
+** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()
+** is negative, then the length of the string is
 ** the number of bytes up to the first zero terminator.
+** If the fourth parameter to sqlite3_bind_blob() is negative, then
+** the behavior is undefined.
 ** If a non-negative fourth parameter is provided to sqlite3_bind_text()
 ** or sqlite3_bind_text16() then that parameter must be the byte offset
 ** where the NUL terminator would occur assuming the string were NUL
@@ -4457,7 +4598,8 @@ SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
 SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
 SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
 SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
-SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
+SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),
+                      void*,sqlite3_int64);
 #endif
 
 /*
@@ -4537,14 +4679,17 @@ SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
 ** In those cases, sqlite3_aggregate_context() might be called for the
 ** first time from within xFinal().)^
 **
-** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer if N is
-** less than or equal to zero or if a memory allocate error occurs.
+** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 
+** when first called if N is less than or equal to zero or if a memory
+** allocate error occurs.
 **
 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is
 ** determined by the N parameter on first successful call.  Changing the
 ** value of N in subsequent call to sqlite3_aggregate_context() within
 ** the same aggregate function instance will not resize the memory
-** allocation.)^
+** allocation.)^  Within the xFinal callback, it is customary to set
+** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 
+** pointless memory allocations occur.
 **
 ** ^SQLite automatically frees the memory allocated by 
 ** sqlite3_aggregate_context() when the aggregate query concludes.
@@ -4587,41 +4732,49 @@ SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*);
 /*
 ** CAPI3REF: Function Auxiliary Data
 **
-** The following two functions may be used by scalar SQL functions to
+** These functions may be used by (non-aggregate) SQL functions to
 ** associate metadata with argument values. If the same value is passed to
 ** multiple invocations of the same SQL function during query execution, under
-** some circumstances the associated metadata may be preserved. This may
-** be used, for example, to add a regular-expression matching scalar
-** function. The compiled version of the regular expression is stored as
-** metadata associated with the SQL value passed as the regular expression
-** pattern.  The compiled regular expression can be reused on multiple
-** invocations of the same function so that the original pattern string
-** does not need to be recompiled on each invocation.
+** some circumstances the associated metadata may be preserved.  An example
+** of where this might be useful is in a regular-expression matching
+** function. The compiled version of the regular expression can be stored as
+** metadata associated with the pattern string.  
+** Then as long as the pattern string remains the same,
+** the compiled regular expression can be reused on multiple
+** invocations of the same function.
 **
 ** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata
 ** associated by the sqlite3_set_auxdata() function with the Nth argument
-** value to the application-defined function. ^If no metadata has been ever
-** been set for the Nth argument of the function, or if the corresponding
-** function parameter has changed since the meta-data was set,
-** then sqlite3_get_auxdata() returns a NULL pointer.
+** value to the application-defined function. ^If there is no metadata
+** associated with the function argument, this sqlite3_get_auxdata() interface
+** returns a NULL pointer.
 **
-** ^The sqlite3_set_auxdata() interface saves the metadata
-** pointed to by its 3rd parameter as the metadata for the N-th
-** argument of the application-defined function.  Subsequent
-** calls to sqlite3_get_auxdata() might return this data, if it has
-** not been destroyed.
-** ^If it is not NULL, SQLite will invoke the destructor
-** function given by the 4th parameter to sqlite3_set_auxdata() on
-** the metadata when the corresponding function parameter changes
-** or when the SQL statement completes, whichever comes first.
+** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th
+** argument of the application-defined function.  ^Subsequent
+** calls to sqlite3_get_auxdata(C,N) return P from the most recent
+** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or
+** NULL if the metadata has been discarded.
+** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,
+** SQLite will invoke the destructor function X with parameter P exactly
+** once, when the metadata is discarded.
+** SQLite is free to discard the metadata at any time, including: <ul>
+** <li> when the corresponding function parameter changes, or
+** <li> when [sqlite3_reset()] or [sqlite3_finalize()] is called for the
+**      SQL statement, or
+** <li> when sqlite3_set_auxdata() is invoked again on the same parameter, or
+** <li> during the original sqlite3_set_auxdata() call when a memory 
+**      allocation error occurs. </ul>)^
 **
-** SQLite is free to call the destructor and drop metadata on any
-** parameter of any function at any time.  ^The only guarantee is that
-** the destructor will be called before the metadata is dropped.
+** Note the last bullet in particular.  The destructor X in 
+** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the
+** sqlite3_set_auxdata() interface even returns.  Hence sqlite3_set_auxdata()
+** should be called near the end of the function implementation and the
+** function implementation should not make any use of P after
+** sqlite3_set_auxdata() has been called.
 **
 ** ^(In practice, metadata is preserved between function calls for
-** expressions that are constant at compile time. This includes literal
-** values and [parameters].)^
+** function parameters that are compile-time constants, including literal
+** values and [parameters] and expressions composed from the same.)^
 **
 ** These routines must be called from the same thread in which
 ** the SQL function is running.
@@ -4642,7 +4795,7 @@ SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(voi
 ** the content before returning.
 **
 ** The typedef is necessary to work around problems in certain
-** C++ compilers.  See ticket #2191.
+** C++ compilers.
 */
 typedef void (*sqlite3_destructor_type)(void*);
 #define SQLITE_STATIC      ((sqlite3_destructor_type)0)
@@ -4695,11 +4848,11 @@ typedef void (*sqlite3_destructor_type)(void*);
 ** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
 **
-** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
-** indicating that a string or BLOB is too long to represent.
+** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
+** error indicating that a string or BLOB is too long to represent.
 **
-** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
-** indicating that a memory allocation failed.
+** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
+** error indicating that a memory allocation failed.
 **
 ** ^The sqlite3_result_int() interface sets the return value
 ** of the application-defined function to be the 32-bit signed integer
@@ -4926,6 +5079,11 @@ SQLITE_API int sqlite3_key(
   sqlite3 *db,                   /* Database to be rekeyed */
   const void *pKey, int nKey     /* The key */
 );
+SQLITE_API int sqlite3_key_v2(
+  sqlite3 *db,                   /* Database to be rekeyed */
+  const char *zDbName,           /* Name of the database */
+  const void *pKey, int nKey     /* The key */
+);
 
 /*
 ** Change the key on an open database.  If the current database is not
@@ -4939,6 +5097,11 @@ SQLITE_API int sqlite3_rekey(
   sqlite3 *db,                   /* Database to be rekeyed */
   const void *pKey, int nKey     /* The new key */
 );
+SQLITE_API int sqlite3_rekey_v2(
+  sqlite3 *db,                   /* Database to be rekeyed */
+  const char *zDbName,           /* Name of the database */
+  const void *pKey, int nKey     /* The new key */
+);
 
 /*
 ** Specify the activation key for a SEE database.  Unless 
@@ -5006,6 +5169,21 @@ SQLITE_API int sqlite3_sleep(int);
 ** Hence, if this variable is modified directly, either it should be
 ** made NULL or made to point to memory obtained from [sqlite3_malloc]
 ** or else the use of the [temp_store_directory pragma] should be avoided.
+**
+** <b>Note to Windows Runtime users:</b>  The temporary directory must be set
+** prior to calling [sqlite3_open] or [sqlite3_open_v2].  Otherwise, various
+** features that require the use of temporary files may fail.  Here is an
+** example of how to do this using C++ with the Windows Runtime:
+**
+** <blockquote><pre>
+** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->
+** &nbsp;     TemporaryFolder->Path->Data();
+** char zPathBuf&#91;MAX_PATH + 1&#93;;
+** memset(zPathBuf, 0, sizeof(zPathBuf));
+** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),
+** &nbsp;     NULL, NULL);
+** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);
+** </pre></blockquote>
 */
 SQLITE_API char *sqlite3_temp_directory;
 
@@ -5246,6 +5424,9 @@ SQLITE_API void *sqlite3_update_hook(
 ** future releases of SQLite.  Applications that care about shared
 ** cache setting should set it explicitly.
 **
+** This interface is threadsafe on processors where writing a
+** 32-bit integer is atomic.
+**
 ** See Also:  [SQLite Shared-Cache Mode]
 */
 SQLITE_API int sqlite3_enable_shared_cache(int);
@@ -5423,11 +5604,20 @@ SQLITE_API int sqlite3_table_column_metadata(
 ** ^This interface loads an SQLite extension library from the named file.
 **
 ** ^The sqlite3_load_extension() interface attempts to load an
-** SQLite extension library contained in the file zFile.
+** [SQLite extension] library contained in the file zFile.  If
+** the file cannot be loaded directly, attempts are made to load
+** with various operating-system specific extensions added.
+** So for example, if "samplelib" cannot be loaded, then names like
+** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might
+** be tried also.
 **
 ** ^The entry point is zProc.
-** ^zProc may be 0, in which case the name of the entry point
-** defaults to "sqlite3_extension_init".
+** ^(zProc may be 0, in which case SQLite will try to come up with an
+** entry point name on its own.  It first tries "sqlite3_extension_init".
+** If that does not work, it constructs a name "sqlite3_X_init" where the
+** X is consists of the lower-case equivalent of all ASCII alphabetic
+** characters in the filename from the last "/" to the first following
+** "." and omitting any initial "lib".)^
 ** ^The sqlite3_load_extension() interface returns
 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.
 ** ^If an error occurs and pzErrMsg is not 0, then the
@@ -5453,11 +5643,11 @@ SQLITE_API int sqlite3_load_extension(
 ** CAPI3REF: Enable Or Disable Extension Loading
 **
 ** ^So as not to open security holes in older applications that are
-** unprepared to deal with extension loading, and as a means of disabling
-** extension loading while evaluating user-entered SQL, the following API
+** unprepared to deal with [extension loading], and as a means of disabling
+** [extension loading] while evaluating user-entered SQL, the following API
 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off.
 **
-** ^Extension loading is off by default. See ticket #1863.
+** ^Extension loading is off by default.
 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1
 ** to turn extension loading on and call it with onoff==0 to turn
 ** it back off again.
@@ -5469,7 +5659,7 @@ SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 **
 ** ^This interface causes the xEntryPoint() function to be invoked for
 ** each new [database connection] that is created.  The idea here is that
-** xEntryPoint() is the entry point for a statically linked SQLite extension
+** xEntryPoint() is the entry point for a statically linked [SQLite extension]
 ** that is to be automatically loaded into all new database connections.
 **
 ** ^(Even though the function prototype shows that xEntryPoint() takes
@@ -5497,10 +5687,23 @@ SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
 ** on the list of automatic extensions is a harmless no-op. ^No entry point
 ** will be called more than once for each database connection that is opened.
 **
-** See also: [sqlite3_reset_auto_extension()].
+** See also: [sqlite3_reset_auto_extension()]
+** and [sqlite3_cancel_auto_extension()]
 */
 SQLITE_API int sqlite3_auto_extension(void (*xEntryPoint)(void));
 
+/*
+** CAPI3REF: Cancel Automatic Extension Loading
+**
+** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the
+** initialization routine X that was registered using a prior call to
+** [sqlite3_auto_extension(X)].  ^The [sqlite3_cancel_auto_extension(X)]
+** routine returns 1 if initialization routine X was successfully 
+** unregistered and it returns 0 if X was not on the list of initialization
+** routines.
+*/
+SQLITE_API int sqlite3_cancel_auto_extension(void (*xEntryPoint)(void));
+
 /*
 ** CAPI3REF: Reset Automatic Extension Loading
 **
@@ -6051,7 +6254,6 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** implementations are available in the SQLite core:
 **
 ** <ul>
-** <li>   SQLITE_MUTEX_OS2
 ** <li>   SQLITE_MUTEX_PTHREADS
 ** <li>   SQLITE_MUTEX_W32
 ** <li>   SQLITE_MUTEX_NOOP
@@ -6059,9 +6261,9 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 **
 ** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
 ** that does no real locking and is appropriate for use in
-** a single-threaded application.  ^The SQLITE_MUTEX_OS2,
-** SQLITE_MUTEX_PTHREADS, and SQLITE_MUTEX_W32 implementations
-** are appropriate for use on OS/2, Unix, and Windows.
+** a single-threaded application.  ^The SQLITE_MUTEX_PTHREADS and
+** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix
+** and Windows.
 **
 ** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
@@ -6614,6 +6816,12 @@ SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int r
 ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The
 ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.
 ** </dd>
+**
+** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>
+** <dd>This parameter returns zero for the current value if and only if
+** all foreign key constraints (deferred or immediate) have been
+** resolved.)^  ^The highwater mark is always 0.
+** </dd>
 ** </dl>
 */
 #define SQLITE_DBSTATUS_LOOKASIDE_USED       0
@@ -6626,7 +6834,8 @@ SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int r
 #define SQLITE_DBSTATUS_CACHE_HIT            7
 #define SQLITE_DBSTATUS_CACHE_MISS           8
 #define SQLITE_DBSTATUS_CACHE_WRITE          9
-#define SQLITE_DBSTATUS_MAX                  9   /* Largest defined DBSTATUS */
+#define SQLITE_DBSTATUS_DEFERRED_FKS        10
+#define SQLITE_DBSTATUS_MAX                 10   /* Largest defined DBSTATUS */
 
 
 /*
@@ -6680,11 +6889,21 @@ SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);
 ** A non-zero value in this counter may indicate an opportunity to
 ** improvement performance by adding permanent indices that do not
 ** need to be reinitialized each time the statement is run.</dd>
+**
+** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>
+** <dd>^This is the number of virtual machine operations executed
+** by the prepared statement if that number is less than or equal
+** to 2147483647.  The number of virtual machine operations can be 
+** used as a proxy for the total work done by the prepared statement.
+** If the number of virtual machine operations exceeds 2147483647
+** then the value returned by this statement status code is undefined.
+** </dd>
 ** </dl>
 */
 #define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
 #define SQLITE_STMTSTATUS_SORT              2
 #define SQLITE_STMTSTATUS_AUTOINDEX         3
+#define SQLITE_STMTSTATUS_VM_STEP           4
 
 /*
 ** CAPI3REF: Custom Page Cache Object
@@ -6821,7 +7040,7 @@ struct sqlite3_pcache_page {
 ** parameter to help it determined what action to take:
 **
 ** <table border=1 width=85% align=center>
-** <tr><th> createFlag <th> Behaviour when page is not already in cache
+** <tr><th> createFlag <th> Behavior when page is not already in cache
 ** <tr><td> 0 <td> Do not allocate a new page.  Return NULL.
 ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.
 **                 Otherwise return NULL.
@@ -7250,10 +7469,25 @@ SQLITE_API int sqlite3_unlock_notify(
 SQLITE_API int sqlite3_stricmp(const char *, const char *);
 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int);
 
+/*
+** CAPI3REF: String Globbing
+*
+** ^The [sqlite3_strglob(P,X)] interface returns zero if string X matches
+** the glob pattern P, and it returns non-zero if string X does not match
+** the glob pattern P.  ^The definition of glob pattern matching used in
+** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the
+** SQL dialect used by SQLite.  ^The sqlite3_strglob(P,X) function is case
+** sensitive.
+**
+** Note that this routine returns zero on a match and non-zero if the strings
+** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].
+*/
+SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr);
+
 /*
 ** CAPI3REF: Error Logging Interface
 **
-** ^The [sqlite3_log()] interface writes a message into the error log
+** ^The [sqlite3_log()] interface writes a message into the [error log]
 ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].
 ** ^If logging is enabled, the zFormat string and subsequent arguments are
 ** used with [sqlite3_snprintf()] to generate the final output string.
@@ -7548,7 +7782,7 @@ SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *);
 #if 0
 }  /* End of the 'extern "C"' block */
 #endif
-#endif
+#endif /* _SQLITE3_H_ */
 
 /*
 ** 2010 August 30
@@ -7626,7 +7860,7 @@ struct sqlite3_rtree_geometry {
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This is the header file for the generic hash-table implemenation
+** This is the header file for the generic hash-table implementation
 ** used in SQLite.
 */
 #ifndef _SQLITE_HASH_H_
@@ -7938,6 +8172,7 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 */
 #ifndef SQLITE_TEMP_STORE
 # define SQLITE_TEMP_STORE 1
+# define SQLITE_TEMP_STORE_xc 1  /* Exclude from ctime.c */
 #endif
 
 /*
@@ -7948,6 +8183,12 @@ SQLITE_PRIVATE void sqlite3HashClear(Hash*);
 #define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))
 #endif
 
+/*
+** Macros to compute minimum and maximum of two numbers.
+*/
+#define MIN(A,B) ((A)<(B)?(A):(B))
+#define MAX(A,B) ((A)>(B)?(A):(B))
+
 /*
 ** Check to see if this machine uses EBCDIC.  (Yes, believe it or
 ** not, there are still machines out there that use EBCDIC.)
@@ -8085,6 +8326,49 @@ SQLITE_PRIVATE const int sqlite3one;
 # define EIGHT_BYTE_ALIGNMENT(X)   ((((char*)(X) - (char*)0)&7)==0)
 #endif
 
+/*
+** Disable MMAP on platforms where it is known to not work
+*/
+#if defined(__OpenBSD__) || defined(__QNXNTO__)
+# undef SQLITE_MAX_MMAP_SIZE
+# define SQLITE_MAX_MMAP_SIZE 0
+#endif
+
+/*
+** Default maximum size of memory used by memory-mapped I/O in the VFS
+*/
+#ifdef __APPLE__
+# include <TargetConditionals.h>
+# if TARGET_OS_IPHONE
+#   undef SQLITE_MAX_MMAP_SIZE
+#   define SQLITE_MAX_MMAP_SIZE 0
+# endif
+#endif
+#ifndef SQLITE_MAX_MMAP_SIZE
+# if defined(__linux__) \
+  || defined(_WIN32) \
+  || (defined(__APPLE__) && defined(__MACH__)) \
+  || defined(__sun)
+#   define SQLITE_MAX_MMAP_SIZE 0x7fff0000  /* 2147418112 */
+# else
+#   define SQLITE_MAX_MMAP_SIZE 0
+# endif
+# define SQLITE_MAX_MMAP_SIZE_xc 1 /* exclude from ctime.c */
+#endif
+
+/*
+** The default MMAP_SIZE is zero on all platforms.  Or, even if a larger
+** default MMAP_SIZE is specified at compile-time, make sure that it does
+** not exceed the maximum mmap size.
+*/
+#ifndef SQLITE_DEFAULT_MMAP_SIZE
+# define SQLITE_DEFAULT_MMAP_SIZE 0
+# define SQLITE_DEFAULT_MMAP_SIZE_xc 1  /* Exclude from ctime.c */
+#endif
+#if SQLITE_DEFAULT_MMAP_SIZE>SQLITE_MAX_MMAP_SIZE
+# undef SQLITE_DEFAULT_MMAP_SIZE
+# define SQLITE_DEFAULT_MMAP_SIZE SQLITE_MAX_MMAP_SIZE
+#endif
 
 /*
 ** An instance of the following structure is used to store the busy-handler
@@ -8126,6 +8410,11 @@ struct BusyHandler {
 */
 #define ArraySize(X)    ((int)(sizeof(X)/sizeof(X[0])))
 
+/*
+** Determine if the argument is a power of two
+*/
+#define IsPowerOfTwo(X) (((X)&((X)-1))==0)
+
 /*
 ** The following value as a destructor means to use sqlite3DbFree().
 ** The sqlite3DbFree() routine requires two parameters instead of the 
@@ -8212,6 +8501,7 @@ typedef struct Parse Parse;
 typedef struct RowSet RowSet;
 typedef struct Savepoint Savepoint;
 typedef struct Select Select;
+typedef struct SelectDest SelectDest;
 typedef struct SrcList SrcList;
 typedef struct StrAccum StrAccum;
 typedef struct Table Table;
@@ -8224,9 +8514,7 @@ typedef struct UnpackedRecord UnpackedRecord;
 typedef struct VTable VTable;
 typedef struct VtabCtx VtabCtx;
 typedef struct Walker Walker;
-typedef struct WherePlan WherePlan;
 typedef struct WhereInfo WhereInfo;
-typedef struct WhereLevel WhereLevel;
 
 /*
 ** Defer sourcing vdbe.h and btree.h until after the "u8" and 
@@ -8300,7 +8588,8 @@ SQLITE_PRIVATE int sqlite3BtreeOpen(
 
 SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
-SQLITE_PRIVATE int sqlite3BtreeSetSafetyLevel(Btree*,int,int,int);
+SQLITE_PRIVATE int sqlite3BtreeSetMmapLimit(Btree*,sqlite3_int64);
+SQLITE_PRIVATE int sqlite3BtreeSetPagerFlags(Btree*,unsigned);
 SQLITE_PRIVATE int sqlite3BtreeSyncDisabled(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree *p, int nPagesize, int nReserve, int eFix);
 SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree*);
@@ -8308,6 +8597,9 @@ SQLITE_PRIVATE int sqlite3BtreeMaxPageCount(Btree*,int);
 SQLITE_PRIVATE u32 sqlite3BtreeLastPage(Btree*);
 SQLITE_PRIVATE int sqlite3BtreeSecureDelete(Btree*,int);
 SQLITE_PRIVATE int sqlite3BtreeGetReserve(Btree*);
+#if defined(SQLITE_HAS_CODEC) || defined(SQLITE_DEBUG)
+SQLITE_PRIVATE int sqlite3BtreeGetReserveNoMutex(Btree *p);
+#endif
 SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *, int);
 SQLITE_PRIVATE int sqlite3BtreeGetAutoVacuum(Btree *);
 SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree*,int);
@@ -8351,6 +8643,8 @@ SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree*, int);
 SQLITE_PRIVATE void sqlite3BtreeGetMeta(Btree *pBtree, int idx, u32 *pValue);
 SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
 
+SQLITE_PRIVATE int sqlite3BtreeNewDb(Btree *p);
+
 /*
 ** The second parameter to sqlite3BtreeGetMeta or sqlite3BtreeUpdateMeta
 ** should be one of the following values. The integer values are assigned 
@@ -8371,6 +8665,13 @@ SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
 #define BTREE_TEXT_ENCODING       5
 #define BTREE_USER_VERSION        6
 #define BTREE_INCR_VACUUM         7
+#define BTREE_APPLICATION_ID      8
+
+/*
+** Values that may be OR'd together to form the second argument of an
+** sqlite3BtreeCursorHints() call.
+*/
+#define BTREE_BULKLOAD 0x00000001
 
 SQLITE_PRIVATE int sqlite3BtreeCursor(
   Btree*,                              /* BTree containing table to open */
@@ -8415,8 +8716,8 @@ SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);
 SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
 SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *);
 SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *);
-
 SQLITE_PRIVATE int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
+SQLITE_PRIVATE void sqlite3BtreeCursorHints(BtCursor *, unsigned int mask);
 
 #ifndef NDEBUG
 SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor*);
@@ -8512,7 +8813,6 @@ typedef struct Vdbe Vdbe;
 ** The names of the following types declared in vdbeInt.h are required
 ** for the VdbeOp definition.
 */
-typedef struct VdbeFunc VdbeFunc;
 typedef struct Mem Mem;
 typedef struct SubProgram SubProgram;
 
@@ -8536,7 +8836,6 @@ struct VdbeOp {
     i64 *pI64;             /* Used when p4type is P4_INT64 */
     double *pReal;         /* Used when p4type is P4_REAL */
     FuncDef *pFunc;        /* Used when p4type is P4_FUNCDEF */
-    VdbeFunc *pVdbeFunc;   /* Used when p4type is P4_VDBEFUNC */
     CollSeq *pColl;        /* Used when p4type is P4_COLLSEQ */
     Mem *pMem;             /* Used when p4type is P4_MEM */
     VTable *pVtab;         /* Used when p4type is P4_VTAB */
@@ -8590,7 +8889,6 @@ typedef struct VdbeOpList VdbeOpList;
 #define P4_COLLSEQ  (-4)  /* P4 is a pointer to a CollSeq structure */
 #define P4_FUNCDEF  (-5)  /* P4 is a pointer to a FuncDef structure */
 #define P4_KEYINFO  (-6)  /* P4 is a pointer to a KeyInfo structure */
-#define P4_VDBEFUNC (-7)  /* P4 is a pointer to a VdbeFunc structure */
 #define P4_MEM      (-8)  /* P4 is a pointer to a Mem*    structure */
 #define P4_TRANSIENT  0   /* P4 is a pointer to a transient string */
 #define P4_VTAB     (-10) /* P4 is a pointer to an sqlite3_vtab structure */
@@ -8647,151 +8945,151 @@ typedef struct VdbeOpList VdbeOpList;
 /************** Begin file opcodes.h *****************************************/
 /* Automatically generated.  Do not edit */
 /* See the mkopcodeh.awk script for details */
-#define OP_Goto                                 1
-#define OP_Gosub                                2
-#define OP_Return                               3
-#define OP_Yield                                4
-#define OP_HaltIfNull                           5
-#define OP_Halt                                 6
-#define OP_Integer                              7
-#define OP_Int64                                8
-#define OP_Real                               130   /* same as TK_FLOAT    */
-#define OP_String8                             94   /* same as TK_STRING   */
-#define OP_String                               9
-#define OP_Null                                10
-#define OP_Blob                                11
-#define OP_Variable                            12
-#define OP_Move                                13
-#define OP_Copy                                14
-#define OP_SCopy                               15
-#define OP_ResultRow                           16
-#define OP_Concat                              91   /* same as TK_CONCAT   */
+#define OP_Function                             1
+#define OP_Savepoint                            2
+#define OP_AutoCommit                           3
+#define OP_Transaction                          4
+#define OP_SorterNext                           5
+#define OP_Prev                                 6
+#define OP_Next                                 7
+#define OP_AggStep                              8
+#define OP_Checkpoint                           9
+#define OP_JournalMode                         10
+#define OP_Vacuum                              11
+#define OP_VFilter                             12
+#define OP_VUpdate                             13
+#define OP_Goto                                14
+#define OP_Gosub                               15
+#define OP_Return                              16
+#define OP_Yield                               17
+#define OP_HaltIfNull                          18
+#define OP_Not                                 19   /* same as TK_NOT      */
+#define OP_Halt                                20
+#define OP_Integer                             21
+#define OP_Int64                               22
+#define OP_String                              23
+#define OP_Null                                24
+#define OP_Blob                                25
+#define OP_Variable                            26
+#define OP_Move                                27
+#define OP_Copy                                28
+#define OP_SCopy                               29
+#define OP_ResultRow                           30
+#define OP_CollSeq                             31
+#define OP_AddImm                              32
+#define OP_MustBeInt                           33
+#define OP_RealAffinity                        34
+#define OP_Permutation                         35
+#define OP_Compare                             36
+#define OP_Jump                                37
+#define OP_Once                                38
+#define OP_If                                  39
+#define OP_IfNot                               40
+#define OP_Column                              41
+#define OP_Affinity                            42
+#define OP_MakeRecord                          43
+#define OP_Count                               44
+#define OP_ReadCookie                          45
+#define OP_SetCookie                           46
+#define OP_VerifyCookie                        47
+#define OP_OpenRead                            48
+#define OP_OpenWrite                           49
+#define OP_OpenAutoindex                       50
+#define OP_OpenEphemeral                       51
+#define OP_SorterOpen                          52
+#define OP_OpenPseudo                          53
+#define OP_Close                               54
+#define OP_SeekLt                              55
+#define OP_SeekLe                              56
+#define OP_SeekGe                              57
+#define OP_SeekGt                              58
+#define OP_Seek                                59
+#define OP_NotFound                            60
+#define OP_Found                               61
+#define OP_IsUnique                            62
+#define OP_NotExists                           63
+#define OP_Sequence                            64
+#define OP_NewRowid                            65
+#define OP_Insert                              66
+#define OP_InsertInt                           67
+#define OP_Or                                  68   /* same as TK_OR       */
+#define OP_And                                 69   /* same as TK_AND      */
+#define OP_Delete                              70
+#define OP_ResetCount                          71
+#define OP_SorterCompare                       72
+#define OP_IsNull                              73   /* same as TK_ISNULL   */
+#define OP_NotNull                             74   /* same as TK_NOTNULL  */
+#define OP_Ne                                  75   /* same as TK_NE       */
+#define OP_Eq                                  76   /* same as TK_EQ       */
+#define OP_Gt                                  77   /* same as TK_GT       */
+#define OP_Le                                  78   /* same as TK_LE       */
+#define OP_Lt                                  79   /* same as TK_LT       */
+#define OP_Ge                                  80   /* same as TK_GE       */
+#define OP_SorterData                          81
+#define OP_BitAnd                              82   /* same as TK_BITAND   */
+#define OP_BitOr                               83   /* same as TK_BITOR    */
+#define OP_ShiftLeft                           84   /* same as TK_LSHIFT   */
+#define OP_ShiftRight                          85   /* same as TK_RSHIFT   */
 #define OP_Add                                 86   /* same as TK_PLUS     */
 #define OP_Subtract                            87   /* same as TK_MINUS    */
 #define OP_Multiply                            88   /* same as TK_STAR     */
 #define OP_Divide                              89   /* same as TK_SLASH    */
 #define OP_Remainder                           90   /* same as TK_REM      */
-#define OP_CollSeq                             17
-#define OP_Function                            18
-#define OP_BitAnd                              82   /* same as TK_BITAND   */
-#define OP_BitOr                               83   /* same as TK_BITOR    */
-#define OP_ShiftLeft                           84   /* same as TK_LSHIFT   */
-#define OP_ShiftRight                          85   /* same as TK_RSHIFT   */
-#define OP_AddImm                              20
-#define OP_MustBeInt                           21
-#define OP_RealAffinity                        22
+#define OP_Concat                              91   /* same as TK_CONCAT   */
+#define OP_RowKey                              92
+#define OP_BitNot                              93   /* same as TK_BITNOT   */
+#define OP_String8                             94   /* same as TK_STRING   */
+#define OP_RowData                             95
+#define OP_Rowid                               96
+#define OP_NullRow                             97
+#define OP_Last                                98
+#define OP_SorterSort                          99
+#define OP_Sort                               100
+#define OP_Rewind                             101
+#define OP_SorterInsert                       102
+#define OP_IdxInsert                          103
+#define OP_IdxDelete                          104
+#define OP_IdxRowid                           105
+#define OP_IdxLT                              106
+#define OP_IdxGE                              107
+#define OP_Destroy                            108
+#define OP_Clear                              109
+#define OP_CreateIndex                        110
+#define OP_CreateTable                        111
+#define OP_ParseSchema                        112
+#define OP_LoadAnalysis                       113
+#define OP_DropTable                          114
+#define OP_DropIndex                          115
+#define OP_DropTrigger                        116
+#define OP_IntegrityCk                        117
+#define OP_RowSetAdd                          118
+#define OP_RowSetRead                         119
+#define OP_RowSetTest                         120
+#define OP_Program                            121
+#define OP_Param                              122
+#define OP_FkCounter                          123
+#define OP_FkIfZero                           124
+#define OP_MemMax                             125
+#define OP_IfPos                              126
+#define OP_IfNeg                              127
+#define OP_IfZero                             128
+#define OP_AggFinal                           129
+#define OP_Real                               130   /* same as TK_FLOAT    */
+#define OP_IncrVacuum                         131
+#define OP_Expire                             132
+#define OP_TableLock                          133
+#define OP_VBegin                             134
+#define OP_VCreate                            135
+#define OP_VDestroy                           136
+#define OP_VOpen                              137
+#define OP_VColumn                            138
+#define OP_VNext                              139
+#define OP_VRename                            140
 #define OP_ToText                             141   /* same as TK_TO_TEXT  */
 #define OP_ToBlob                             142   /* same as TK_TO_BLOB  */
 #define OP_ToNumeric                          143   /* same as TK_TO_NUMERIC*/
 #define OP_ToInt                              144   /* same as TK_TO_INT   */
 #define OP_ToReal                             145   /* same as TK_TO_REAL  */
-#define OP_Eq                                  76   /* same as TK_EQ       */
-#define OP_Ne                                  75   /* same as TK_NE       */
-#define OP_Lt                                  79   /* same as TK_LT       */
-#define OP_Le                                  78   /* same as TK_LE       */
-#define OP_Gt                                  77   /* same as TK_GT       */
-#define OP_Ge                                  80   /* same as TK_GE       */
-#define OP_Permutation                         23
-#define OP_Compare                             24
-#define OP_Jump                                25
-#define OP_And                                 69   /* same as TK_AND      */
-#define OP_Or                                  68   /* same as TK_OR       */
-#define OP_Not                                 19   /* same as TK_NOT      */
-#define OP_BitNot                              93   /* same as TK_BITNOT   */
-#define OP_Once                                26
-#define OP_If                                  27
-#define OP_IfNot                               28
-#define OP_IsNull                              73   /* same as TK_ISNULL   */
-#define OP_NotNull                             74   /* same as TK_NOTNULL  */
-#define OP_Column                              29
-#define OP_Affinity                            30
-#define OP_MakeRecord                          31
-#define OP_Count                               32
-#define OP_Savepoint                           33
-#define OP_AutoCommit                          34
-#define OP_Transaction                         35
-#define OP_ReadCookie                          36
-#define OP_SetCookie                           37
-#define OP_VerifyCookie                        38
-#define OP_OpenRead                            39
-#define OP_OpenWrite                           40
-#define OP_OpenAutoindex                       41
-#define OP_OpenEphemeral                       42
-#define OP_SorterOpen                          43
-#define OP_OpenPseudo                          44
-#define OP_Close                               45
-#define OP_SeekLt                              46
-#define OP_SeekLe                              47
-#define OP_SeekGe                              48
-#define OP_SeekGt                              49
-#define OP_Seek                                50
-#define OP_NotFound                            51
-#define OP_Found                               52
-#define OP_IsUnique                            53
-#define OP_NotExists                           54
-#define OP_Sequence                            55
-#define OP_NewRowid                            56
-#define OP_Insert                              57
-#define OP_InsertInt                           58
-#define OP_Delete                              59
-#define OP_ResetCount                          60
-#define OP_SorterCompare                       61
-#define OP_SorterData                          62
-#define OP_RowKey                              63
-#define OP_RowData                             64
-#define OP_Rowid                               65
-#define OP_NullRow                             66
-#define OP_Last                                67
-#define OP_SorterSort                          70
-#define OP_Sort                                71
-#define OP_Rewind                              72
-#define OP_SorterNext                          81
-#define OP_Prev                                92
-#define OP_Next                                95
-#define OP_SorterInsert                        96
-#define OP_IdxInsert                           97
-#define OP_IdxDelete                           98
-#define OP_IdxRowid                            99
-#define OP_IdxLT                              100
-#define OP_IdxGE                              101
-#define OP_Destroy                            102
-#define OP_Clear                              103
-#define OP_CreateIndex                        104
-#define OP_CreateTable                        105
-#define OP_ParseSchema                        106
-#define OP_LoadAnalysis                       107
-#define OP_DropTable                          108
-#define OP_DropIndex                          109
-#define OP_DropTrigger                        110
-#define OP_IntegrityCk                        111
-#define OP_RowSetAdd                          112
-#define OP_RowSetRead                         113
-#define OP_RowSetTest                         114
-#define OP_Program                            115
-#define OP_Param                              116
-#define OP_FkCounter                          117
-#define OP_FkIfZero                           118
-#define OP_MemMax                             119
-#define OP_IfPos                              120
-#define OP_IfNeg                              121
-#define OP_IfZero                             122
-#define OP_AggStep                            123
-#define OP_AggFinal                           124
-#define OP_Checkpoint                         125
-#define OP_JournalMode                        126
-#define OP_Vacuum                             127
-#define OP_IncrVacuum                         128
-#define OP_Expire                             129
-#define OP_TableLock                          131
-#define OP_VBegin                             132
-#define OP_VCreate                            133
-#define OP_VDestroy                           134
-#define OP_VOpen                              135
-#define OP_VFilter                            136
-#define OP_VColumn                            137
-#define OP_VNext                              138
-#define OP_VRename                            139
-#define OP_VUpdate                            140
 #define OP_Pagecount                          146
 #define OP_MaxPgcnt                           147
 #define OP_Trace                              148
@@ -8811,24 +9109,24 @@ typedef struct VdbeOpList VdbeOpList;
 #define OPFLG_OUT2            0x0020  /* out2:  P2 is an output */
 #define OPFLG_OUT3            0x0040  /* out3:  P3 is an output */
 #define OPFLG_INITIALIZER {\
-/*   0 */ 0x00, 0x01, 0x01, 0x04, 0x04, 0x10, 0x00, 0x02,\
-/*   8 */ 0x02, 0x02, 0x02, 0x02, 0x02, 0x00, 0x24, 0x24,\
-/*  16 */ 0x00, 0x00, 0x00, 0x24, 0x04, 0x05, 0x04, 0x00,\
-/*  24 */ 0x00, 0x01, 0x01, 0x05, 0x05, 0x00, 0x00, 0x00,\
-/*  32 */ 0x02, 0x00, 0x00, 0x00, 0x02, 0x10, 0x00, 0x00,\
-/*  40 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x11, 0x11,\
-/*  48 */ 0x11, 0x11, 0x08, 0x11, 0x11, 0x11, 0x11, 0x02,\
-/*  56 */ 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
-/*  64 */ 0x00, 0x02, 0x00, 0x01, 0x4c, 0x4c, 0x01, 0x01,\
-/*  72 */ 0x01, 0x05, 0x05, 0x15, 0x15, 0x15, 0x15, 0x15,\
-/*  80 */ 0x15, 0x01, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c,\
-/*  88 */ 0x4c, 0x4c, 0x4c, 0x4c, 0x01, 0x24, 0x02, 0x01,\
-/*  96 */ 0x08, 0x08, 0x00, 0x02, 0x01, 0x01, 0x02, 0x00,\
-/* 104 */ 0x02, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
-/* 112 */ 0x0c, 0x45, 0x15, 0x01, 0x02, 0x00, 0x01, 0x08,\
-/* 120 */ 0x05, 0x05, 0x05, 0x00, 0x00, 0x00, 0x02, 0x00,\
-/* 128 */ 0x01, 0x00, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00,\
-/* 136 */ 0x01, 0x00, 0x01, 0x00, 0x00, 0x04, 0x04, 0x04,\
+/*   0 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01,\
+/*   8 */ 0x00, 0x00, 0x02, 0x00, 0x01, 0x00, 0x01, 0x01,\
+/*  16 */ 0x04, 0x04, 0x10, 0x24, 0x00, 0x02, 0x02, 0x02,\
+/*  24 */ 0x02, 0x02, 0x02, 0x00, 0x00, 0x24, 0x00, 0x00,\
+/*  32 */ 0x04, 0x05, 0x04, 0x00, 0x00, 0x01, 0x01, 0x05,\
+/*  40 */ 0x05, 0x00, 0x00, 0x00, 0x02, 0x02, 0x10, 0x00,\
+/*  48 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x11,\
+/*  56 */ 0x11, 0x11, 0x11, 0x08, 0x11, 0x11, 0x11, 0x11,\
+/*  64 */ 0x02, 0x02, 0x00, 0x00, 0x4c, 0x4c, 0x00, 0x00,\
+/*  72 */ 0x00, 0x05, 0x05, 0x15, 0x15, 0x15, 0x15, 0x15,\
+/*  80 */ 0x15, 0x00, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c, 0x4c,\
+/*  88 */ 0x4c, 0x4c, 0x4c, 0x4c, 0x00, 0x24, 0x02, 0x00,\
+/*  96 */ 0x02, 0x00, 0x01, 0x01, 0x01, 0x01, 0x08, 0x08,\
+/* 104 */ 0x00, 0x02, 0x01, 0x01, 0x02, 0x00, 0x02, 0x02,\
+/* 112 */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0c, 0x45,\
+/* 120 */ 0x15, 0x01, 0x02, 0x00, 0x01, 0x08, 0x05, 0x05,\
+/* 128 */ 0x05, 0x00, 0x02, 0x01, 0x00, 0x00, 0x00, 0x00,\
+/* 136 */ 0x00, 0x00, 0x00, 0x01, 0x00, 0x04, 0x04, 0x04,\
 /* 144 */ 0x04, 0x04, 0x02, 0x02, 0x00, 0x00, 0x00,}
 
 /************** End of opcodes.h *********************************************/
@@ -8859,7 +9157,7 @@ SQLITE_PRIVATE VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
 SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeRunOnlyOnce(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe*);
-SQLITE_PRIVATE void sqlite3VdbeDeleteObject(sqlite3*,Vdbe*);
+SQLITE_PRIVATE void sqlite3VdbeClearObject(sqlite3*,Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeMakeReady(Vdbe*,Parse*);
 SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe*, int);
@@ -8878,7 +9176,7 @@ SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe*);
 SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe*, const char *z, int n, int);
 SQLITE_PRIVATE void sqlite3VdbeSwap(Vdbe*,Vdbe*);
 SQLITE_PRIVATE VdbeOp *sqlite3VdbeTakeOpArray(Vdbe*, int*, int*);
-SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetValue(Vdbe*, int, u8);
+SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetBoundValue(Vdbe*, int, u8);
 SQLITE_PRIVATE void sqlite3VdbeSetVarmask(Vdbe*, int);
 #ifndef SQLITE_OMIT_TRACE
 SQLITE_PRIVATE   char *sqlite3VdbeExpandSql(Vdbe*, const char*);
@@ -8989,6 +9287,24 @@ typedef struct PgHdr DbPage;
 #define PAGER_JOURNALMODE_MEMORY      4   /* In-memory journal file */
 #define PAGER_JOURNALMODE_WAL         5   /* Use write-ahead logging */
 
+/*
+** Flags that make up the mask passed to sqlite3PagerAcquire().
+*/
+#define PAGER_GET_NOCONTENT     0x01  /* Do not load data from disk */
+#define PAGER_GET_READONLY      0x02  /* Read-only page is acceptable */
+
+/*
+** Flags for sqlite3PagerSetFlags()
+*/
+#define PAGER_SYNCHRONOUS_OFF       0x01  /* PRAGMA synchronous=OFF */
+#define PAGER_SYNCHRONOUS_NORMAL    0x02  /* PRAGMA synchronous=NORMAL */
+#define PAGER_SYNCHRONOUS_FULL      0x03  /* PRAGMA synchronous=FULL */
+#define PAGER_SYNCHRONOUS_MASK      0x03  /* Mask for three values above */
+#define PAGER_FULLFSYNC             0x04  /* PRAGMA fullfsync=ON */
+#define PAGER_CKPT_FULLFSYNC        0x08  /* PRAGMA checkpoint_fullfsync=ON */
+#define PAGER_CACHESPILL            0x10  /* PRAGMA cache_spill=ON */
+#define PAGER_FLAGS_MASK            0x1c  /* All above except SYNCHRONOUS */
+
 /*
 ** The remainder of this file contains the declarations of the functions
 ** that make up the Pager sub-system API. See source code comments for 
@@ -9013,8 +9329,9 @@ SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, int(*)(void *), void *);
 SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u32*, int);
 SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
 SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
+SQLITE_PRIVATE void sqlite3PagerSetMmapLimit(Pager *, sqlite3_int64);
 SQLITE_PRIVATE void sqlite3PagerShrink(Pager*);
-SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(Pager*,int,int,int);
+SQLITE_PRIVATE void sqlite3PagerSetFlags(Pager*,unsigned);
 SQLITE_PRIVATE int sqlite3PagerLockingMode(Pager *, int);
 SQLITE_PRIVATE int sqlite3PagerSetJournalMode(Pager *, int);
 SQLITE_PRIVATE int sqlite3PagerGetJournalMode(Pager*);
@@ -9049,11 +9366,14 @@ SQLITE_PRIVATE int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
 SQLITE_PRIVATE int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
 SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager);
 
-SQLITE_PRIVATE int sqlite3PagerCheckpoint(Pager *pPager, int, int*, int*);
-SQLITE_PRIVATE int sqlite3PagerWalSupported(Pager *pPager);
-SQLITE_PRIVATE int sqlite3PagerWalCallback(Pager *pPager);
-SQLITE_PRIVATE int sqlite3PagerOpenWal(Pager *pPager, int *pisOpen);
-SQLITE_PRIVATE int sqlite3PagerCloseWal(Pager *pPager);
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE   int sqlite3PagerCheckpoint(Pager *pPager, int, int*, int*);
+SQLITE_PRIVATE   int sqlite3PagerWalSupported(Pager *pPager);
+SQLITE_PRIVATE   int sqlite3PagerWalCallback(Pager *pPager);
+SQLITE_PRIVATE   int sqlite3PagerOpenWal(Pager *pPager, int *pisOpen);
+SQLITE_PRIVATE   int sqlite3PagerCloseWal(Pager *pPager);
+#endif
+
 #ifdef SQLITE_ENABLE_ZIPVFS
 SQLITE_PRIVATE   int sqlite3PagerWalFramesize(Pager *pPager);
 #endif
@@ -9071,6 +9391,7 @@ SQLITE_PRIVATE void *sqlite3PagerTempSpace(Pager*);
 SQLITE_PRIVATE int sqlite3PagerIsMemdb(Pager*);
 SQLITE_PRIVATE void sqlite3PagerCacheStat(Pager *, int, int, int *);
 SQLITE_PRIVATE void sqlite3PagerClearCache(Pager *);
+SQLITE_PRIVATE int sqlite3SectorSize(sqlite3_file *);
 
 /* Functions used to truncate the database file. */
 SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager*,Pgno);
@@ -9155,6 +9476,8 @@ struct PgHdr {
 #define PGHDR_REUSE_UNLIKELY    0x010  /* A hint that reuse is unlikely */
 #define PGHDR_DONT_WRITE        0x020  /* Do not write content to disk */
 
+#define PGHDR_MMAP              0x040  /* This is an mmap page object */
+
 /* Initialize and shutdown the page cache subsystem */
 SQLITE_PRIVATE int sqlite3PcacheInitialize(void);
 SQLITE_PRIVATE void sqlite3PcacheShutdown(void);
@@ -9290,7 +9613,7 @@ SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
 /*
 ** Figure out if we are dealing with Unix, Windows, or some other
 ** operating system.  After the following block of preprocess macros,
-** all of SQLITE_OS_UNIX, SQLITE_OS_WIN, SQLITE_OS_OS2, and SQLITE_OS_OTHER 
+** all of SQLITE_OS_UNIX, SQLITE_OS_WIN, and SQLITE_OS_OTHER 
 ** will defined to either 1 or 0.  One of the four will be 1.  The other 
 ** three will be 0.
 */
@@ -9300,8 +9623,6 @@ SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
 #   define SQLITE_OS_UNIX 0
 #   undef SQLITE_OS_WIN
 #   define SQLITE_OS_WIN 0
-#   undef SQLITE_OS_OS2
-#   define SQLITE_OS_OS2 0
 # else
 #   undef SQLITE_OS_OTHER
 # endif
@@ -9312,19 +9633,12 @@ SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
 #   if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__)
 #     define SQLITE_OS_WIN 1
 #     define SQLITE_OS_UNIX 0
-#     define SQLITE_OS_OS2 0
-#   elif defined(__EMX__) || defined(_OS2) || defined(OS2) || defined(_OS2_) || defined(__OS2__)
-#     define SQLITE_OS_WIN 0
-#     define SQLITE_OS_UNIX 0
-#     define SQLITE_OS_OS2 1
 #   else
 #     define SQLITE_OS_WIN 0
 #     define SQLITE_OS_UNIX 1
-#     define SQLITE_OS_OS2 0
 #  endif
 # else
 #  define SQLITE_OS_UNIX 0
-#  define SQLITE_OS_OS2 0
 # endif
 #else
 # ifndef SQLITE_OS_WIN
@@ -9336,21 +9650,6 @@ SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
 # include <windows.h>
 #endif
 
-#if SQLITE_OS_OS2
-# if (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && defined(OS2_HIGH_MEMORY)
-#  include <os2safe.h> /* has to be included before os2.h for linking to work */
-# endif
-# define INCL_DOSDATETIME
-# define INCL_DOSFILEMGR
-# define INCL_DOSERRORS
-# define INCL_DOSMISC
-# define INCL_DOSPROCESS
-# define INCL_DOSMODULEMGR
-# define INCL_DOSSEMAPHORES
-# include <os2.h>
-# include <uconv.h>
-#endif
-
 /*
 ** Determine if we are dealing with Windows NT.
 **
@@ -9383,21 +9682,13 @@ SQLITE_PRIVATE void sqlite3PCacheSetDefault(void);
 #endif
 
 /*
-** Determine if we are dealing with WindowsRT (Metro) as this has a different and
-** incompatible API from win32.
+** Determine if we are dealing with WinRT, which provides only a subset of
+** the full Win32 API.
 */
 #if !defined(SQLITE_OS_WINRT)
 # define SQLITE_OS_WINRT 0
 #endif
 
-/*
-** When compiled for WinCE or WinRT, there is no concept of the current
-** directory.
- */
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
-# define SQLITE_CURDIR 1
-#endif
-
 /* If the SET_FULLSYNC macro is not defined above, then make it
 ** a no-op
 */
@@ -9550,6 +9841,8 @@ SQLITE_PRIVATE int sqlite3OsShmMap(sqlite3_file *,int,int,int,void volatile **);
 SQLITE_PRIVATE int sqlite3OsShmLock(sqlite3_file *id, int, int, int);
 SQLITE_PRIVATE void sqlite3OsShmBarrier(sqlite3_file *id);
 SQLITE_PRIVATE int sqlite3OsShmUnmap(sqlite3_file *id, int);
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64, int, void **);
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *, i64, void *);
 
 
 /* 
@@ -9620,8 +9913,6 @@ SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *);
 **   SQLITE_MUTEX_PTHREADS     For multi-threaded applications on Unix.
 **
 **   SQLITE_MUTEX_W32          For multi-threaded applications on Win32.
-**
-**   SQLITE_MUTEX_OS2          For multi-threaded applications on OS/2.
 */
 #if !SQLITE_THREADSAFE
 # define SQLITE_MUTEX_OMIT
@@ -9631,8 +9922,6 @@ SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *);
 #    define SQLITE_MUTEX_PTHREADS
 #  elif SQLITE_OS_WIN
 #    define SQLITE_MUTEX_W32
-#  elif SQLITE_OS_OS2
-#    define SQLITE_MUTEX_OS2
 #  else
 #    define SQLITE_MUTEX_NOOP
 #  endif
@@ -9671,7 +9960,6 @@ SQLITE_PRIVATE int sqlite3OsCloseFree(sqlite3_file *);
 struct Db {
   char *zName;         /* Name of this database */
   Btree *pBt;          /* The B*Tree structure for this database file */
-  u8 inTrans;          /* 0: not writable.  1: Transaction.  2: Checkpoint */
   u8 safety_level;     /* How aggressive at syncing data to disk */
   Schema *pSchema;     /* Pointer to database schema (possibly shared) */
 };
@@ -9793,9 +10081,11 @@ struct sqlite3 {
   int nDb;                      /* Number of backends currently in use */
   int flags;                    /* Miscellaneous flags. See below */
   i64 lastRowid;                /* ROWID of most recent insert (see above) */
+  i64 szMmap;                   /* Default mmap_size setting */
   unsigned int openFlags;       /* Flags passed to sqlite3_vfs.xOpen() */
   int errCode;                  /* Most recent error code (SQLITE_*) */
   int errMask;                  /* & result codes with this before returning */
+  u16 dbOptFlags;               /* Flags to enable/disable optimizations */
   u8 autoCommit;                /* The auto-commit flag. */
   u8 temp_store;                /* 1: file 2: memory 0: default */
   u8 mallocFailed;              /* True if we have seen a malloc failure */
@@ -9815,9 +10105,10 @@ struct sqlite3 {
     u8 busy;                    /* TRUE if currently initializing */
     u8 orphanTrigger;           /* Last statement is orphaned TEMP trigger */
   } init;
-  int activeVdbeCnt;            /* Number of VDBEs currently executing */
-  int writeVdbeCnt;             /* Number of active VDBEs that are writing */
-  int vdbeExecCnt;              /* Number of nested calls to VdbeExec() */
+  int nVdbeActive;              /* Number of VDBEs currently running */
+  int nVdbeRead;                /* Number of active VDBEs that read or write */
+  int nVdbeWrite;               /* Number of active VDBEs that read and write */
+  int nVdbeExec;                /* Number of nested calls to VdbeExec() */
   int nExtension;               /* Number of loaded extensions */
   void **aExtension;            /* Array of shared library handles */
   void (*xTrace)(void*,const char*);        /* Trace function */
@@ -9853,7 +10144,7 @@ struct sqlite3 {
 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
   int (*xProgress)(void *);     /* The progress callback */
   void *pProgressArg;           /* Argument to the progress callback */
-  int nProgressOps;             /* Number of opcodes for progress callback */
+  unsigned nProgressOps;        /* Number of opcodes for progress callback */
 #endif
 #ifndef SQLITE_OMIT_VIRTUALTABLE
   int nVTrans;                  /* Allocated size of aVTrans */
@@ -9871,6 +10162,7 @@ struct sqlite3 {
   int nSavepoint;               /* Number of non-transaction savepoints */
   int nStatement;               /* Number of nested statement-transactions  */
   i64 nDeferredCons;            /* Net deferred constraints this transaction. */
+  i64 nDeferredImmCons;         /* Net deferred immediate constraints */
   int *pnBytesFreed;            /* If not NULL, increment this in DbFree() */
 
 #ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
@@ -9900,48 +10192,66 @@ struct sqlite3 {
 /*
 ** Possible values for the sqlite3.flags.
 */
-#define SQLITE_VdbeTrace      0x00000100  /* True to trace VDBE execution */
-#define SQLITE_InternChanges  0x00000200  /* Uncommitted Hash table changes */
-#define SQLITE_FullColNames   0x00000400  /* Show full column names on SELECT */
-#define SQLITE_ShortColNames  0x00000800  /* Show short columns names */
-#define SQLITE_CountRows      0x00001000  /* Count rows changed by INSERT, */
+#define SQLITE_VdbeTrace      0x00000001  /* True to trace VDBE execution */
+#define SQLITE_InternChanges  0x00000002  /* Uncommitted Hash table changes */
+#define SQLITE_FullFSync      0x00000004  /* Use full fsync on the backend */
+#define SQLITE_CkptFullFSync  0x00000008  /* Use full fsync for checkpoint */
+#define SQLITE_CacheSpill     0x00000010  /* OK to spill pager cache */
+#define SQLITE_FullColNames   0x00000020  /* Show full column names on SELECT */
+#define SQLITE_ShortColNames  0x00000040  /* Show short columns names */
+#define SQLITE_CountRows      0x00000080  /* Count rows changed by INSERT, */
                                           /*   DELETE, or UPDATE and return */
                                           /*   the count using a callback. */
-#define SQLITE_NullCallback   0x00002000  /* Invoke the callback once if the */
+#define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
                                           /*   result set is empty */
-#define SQLITE_SqlTrace       0x00004000  /* Debug print SQL as it executes */
-#define SQLITE_VdbeListing    0x00008000  /* Debug listings of VDBE programs */
-#define SQLITE_WriteSchema    0x00010000  /* OK to update SQLITE_MASTER */
-                         /*   0x00020000  Unused */
-#define SQLITE_IgnoreChecks   0x00040000  /* Do not enforce check constraints */
-#define SQLITE_ReadUncommitted 0x0080000  /* For shared-cache mode */
-#define SQLITE_LegacyFileFmt  0x00100000  /* Create new databases in format 1 */
-#define SQLITE_FullFSync      0x00200000  /* Use full fsync on the backend */
-#define SQLITE_CkptFullFSync  0x00400000  /* Use full fsync for checkpoint */
-#define SQLITE_RecoveryMode   0x00800000  /* Ignore schema errors */
-#define SQLITE_ReverseOrder   0x01000000  /* Reverse unordered SELECTs */
-#define SQLITE_RecTriggers    0x02000000  /* Enable recursive triggers */
-#define SQLITE_ForeignKeys    0x04000000  /* Enforce foreign key constraints  */
-#define SQLITE_AutoIndex      0x08000000  /* Enable automatic indexes */
-#define SQLITE_PreferBuiltin  0x10000000  /* Preference to built-in funcs */
-#define SQLITE_LoadExtension  0x20000000  /* Enable load_extension */
-#define SQLITE_EnableTrigger  0x40000000  /* True to enable triggers */
+#define SQLITE_SqlTrace       0x00000200  /* Debug print SQL as it executes */
+#define SQLITE_VdbeListing    0x00000400  /* Debug listings of VDBE programs */
+#define SQLITE_WriteSchema    0x00000800  /* OK to update SQLITE_MASTER */
+#define SQLITE_VdbeAddopTrace 0x00001000  /* Trace sqlite3VdbeAddOp() calls */
+#define SQLITE_IgnoreChecks   0x00002000  /* Do not enforce check constraints */
+#define SQLITE_ReadUncommitted 0x0004000  /* For shared-cache mode */
+#define SQLITE_LegacyFileFmt  0x00008000  /* Create new databases in format 1 */
+#define SQLITE_RecoveryMode   0x00010000  /* Ignore schema errors */
+#define SQLITE_ReverseOrder   0x00020000  /* Reverse unordered SELECTs */
+#define SQLITE_RecTriggers    0x00040000  /* Enable recursive triggers */
+#define SQLITE_ForeignKeys    0x00080000  /* Enforce foreign key constraints  */
+#define SQLITE_AutoIndex      0x00100000  /* Enable automatic indexes */
+#define SQLITE_PreferBuiltin  0x00200000  /* Preference to built-in funcs */
+#define SQLITE_LoadExtension  0x00400000  /* Enable load_extension */
+#define SQLITE_EnableTrigger  0x00800000  /* True to enable triggers */
+#define SQLITE_DeferFKs       0x01000000  /* Defer all FK constraints */
+#define SQLITE_QueryOnly      0x02000000  /* Disable database changes */
+
 
 /*
-** Bits of the sqlite3.flags field that are used by the
-** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface.
-** These must be the low-order bits of the flags field.
+** Bits of the sqlite3.dbOptFlags field that are used by the
+** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
+** selectively disable various optimizations.
 */
-#define SQLITE_QueryFlattener 0x01        /* Disable query flattening */
-#define SQLITE_ColumnCache    0x02        /* Disable the column cache */
-#define SQLITE_IndexSort      0x04        /* Disable indexes for sorting */
-#define SQLITE_IndexSearch    0x08        /* Disable indexes for searching */
-#define SQLITE_IndexCover     0x10        /* Disable index covering table */
-#define SQLITE_GroupByOrder   0x20        /* Disable GROUPBY cover of ORDERBY */
-#define SQLITE_FactorOutConst 0x40        /* Disable factoring out constants */
-#define SQLITE_IdxRealAsInt   0x80        /* Store REAL as INT in indices */
-#define SQLITE_DistinctOpt    0x80        /* DISTINCT using indexes */
-#define SQLITE_OptMask        0xff        /* Mask of all disablable opts */
+#define SQLITE_QueryFlattener 0x0001   /* Query flattening */
+#define SQLITE_ColumnCache    0x0002   /* Column cache */
+#define SQLITE_GroupByOrder   0x0004   /* GROUPBY cover of ORDERBY */
+#define SQLITE_FactorOutConst 0x0008   /* Constant factoring */
+#define SQLITE_IdxRealAsInt   0x0010   /* Store REAL as INT in indices */
+#define SQLITE_DistinctOpt    0x0020   /* DISTINCT using indexes */
+#define SQLITE_CoverIdxScan   0x0040   /* Covering index scans */
+#define SQLITE_OrderByIdxJoin 0x0080   /* ORDER BY of joins via index */
+#define SQLITE_SubqCoroutine  0x0100   /* Evaluate subqueries as coroutines */
+#define SQLITE_Transitive     0x0200   /* Transitive constraints */
+#define SQLITE_OmitNoopJoin   0x0400   /* Omit unused tables in joins */
+#define SQLITE_Stat3          0x0800   /* Use the SQLITE_STAT3 table */
+#define SQLITE_AllOpts        0xffff   /* All optimizations */
+
+/*
+** Macros for testing whether or not optimizations are enabled or disabled.
+*/
+#ifndef SQLITE_OMIT_BUILTIN_TEST
+#define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
+#define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)
+#else
+#define OptimizationDisabled(db, mask)  0
+#define OptimizationEnabled(db, mask)   1
+#endif
 
 /*
 ** Possible values for the sqlite.magic field.
@@ -9953,6 +10263,7 @@ struct sqlite3 {
 #define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
 #define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
 #define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
+#define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */
 
 /*
 ** Each SQL function is defined by an instance of the following
@@ -10057,6 +10368,7 @@ struct FuncDestructor {
 struct Savepoint {
   char *zName;                        /* Savepoint name (nul-terminated) */
   i64 nDeferredCons;                  /* Number of deferred fk violations */
+  i64 nDeferredImmCons;               /* Number of deferred imm fk. */
   Savepoint *pNext;                   /* Parent savepoint (if any) */
 };
 
@@ -10091,32 +10403,22 @@ struct Column {
   char *zDflt;     /* Original text of the default value */
   char *zType;     /* Data type for this column */
   char *zColl;     /* Collating sequence.  If NULL, use the default */
-  u8 notNull;      /* True if there is a NOT NULL constraint */
-  u8 isPrimKey;    /* True if this column is part of the PRIMARY KEY */
+  u8 notNull;      /* An OE_ code for handling a NOT NULL constraint */
   char affinity;   /* One of the SQLITE_AFF_... values */
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  u8 isHidden;     /* True if this column is 'hidden' */
-#endif
+  u16 colFlags;    /* Boolean properties.  See COLFLAG_ defines below */
 };
 
+/* Allowed values for Column.colFlags:
+*/
+#define COLFLAG_PRIMKEY  0x0001    /* Column is part of the primary key */
+#define COLFLAG_HIDDEN   0x0002    /* A hidden column in a virtual table */
+
 /*
 ** A "Collating Sequence" is defined by an instance of the following
 ** structure. Conceptually, a collating sequence consists of a name and
 ** a comparison routine that defines the order of that sequence.
 **
-** There may two separate implementations of the collation function, one
-** that processes text in UTF-8 encoding (CollSeq.xCmp) and another that
-** processes text encoded in UTF-16 (CollSeq.xCmp16), using the machine
-** native byte order. When a collation sequence is invoked, SQLite selects
-** the version that will require the least expensive encoding
-** translations, if any.
-**
-** The CollSeq.pUser member variable is an extra parameter that passed in
-** as the first argument to the UTF-8 comparison function, xCmp.
-** CollSeq.pUser16 is the equivalent for the UTF-16 comparison function,
-** xCmp16.
-**
-** If both CollSeq.xCmp and CollSeq.xCmp16 are NULL, it means that the
+** If CollSeq.xCmp is NULL, it means that the
 ** collating sequence is undefined.  Indices built on an undefined
 ** collating sequence may not be read or written.
 */
@@ -10254,28 +10556,28 @@ struct VTable {
 */
 struct Table {
   char *zName;         /* Name of the table or view */
-  int iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
-  int nCol;            /* Number of columns in this table */
   Column *aCol;        /* Information about each column */
   Index *pIndex;       /* List of SQL indexes on this table. */
-  int tnum;            /* Root BTree node for this table (see note above) */
-  tRowcnt nRowEst;     /* Estimated rows in table - from sqlite_stat1 table */
   Select *pSelect;     /* NULL for tables.  Points to definition if a view. */
-  u16 nRef;            /* Number of pointers to this Table */
-  u8 tabFlags;         /* Mask of TF_* values */
-  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
   FKey *pFKey;         /* Linked list of all foreign keys in this table */
   char *zColAff;       /* String defining the affinity of each column */
 #ifndef SQLITE_OMIT_CHECK
   ExprList *pCheck;    /* All CHECK constraints */
 #endif
+  tRowcnt nRowEst;     /* Estimated rows in table - from sqlite_stat1 table */
+  int tnum;            /* Root BTree node for this table (see note above) */
+  i16 iPKey;           /* If not negative, use aCol[iPKey] as the primary key */
+  i16 nCol;            /* Number of columns in this table */
+  u16 nRef;            /* Number of pointers to this Table */
+  u8 tabFlags;         /* Mask of TF_* values */
+  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
 #ifndef SQLITE_OMIT_ALTERTABLE
   int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
 #endif
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  VTable *pVTable;     /* List of VTable objects. */
   int nModuleArg;      /* Number of arguments to the module */
   char **azModuleArg;  /* Text of all module args. [0] is module name */
+  VTable *pVTable;     /* List of VTable objects. */
 #endif
   Trigger *pTrigger;   /* List of triggers stored in pSchema */
   Schema *pSchema;     /* Schema that contains this table */
@@ -10299,7 +10601,7 @@ struct Table {
 */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
 #  define IsVirtual(X)      (((X)->tabFlags & TF_Virtual)!=0)
-#  define IsHiddenColumn(X) ((X)->isHidden)
+#  define IsHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
 #else
 #  define IsVirtual(X)      0
 #  define IsHiddenColumn(X) 0
@@ -10385,12 +10687,16 @@ struct FKey {
 ** An instance of the following structure is passed as the first
 ** argument to sqlite3VdbeKeyCompare and is used to control the 
 ** comparison of the two index keys.
+**
+** Note that aSortOrder[] and aColl[] have nField+1 slots.  There
+** are nField slots for the columns of an index then one extra slot
+** for the rowid at the end.
 */
 struct KeyInfo {
   sqlite3 *db;        /* The database connection */
   u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
-  u16 nField;         /* Number of entries in aColl[] */
-  u8 *aSortOrder;     /* Sort order for each column.  May be NULL */
+  u16 nField;         /* Maximum index for aColl[] and aSortOrder[] */
+  u8 *aSortOrder;     /* Sort order for each column. */
   CollSeq *aColl[1];  /* Collating sequence for each term of the key */
 };
 
@@ -10450,20 +10756,22 @@ struct UnpackedRecord {
 ** element.
 */
 struct Index {
-  char *zName;     /* Name of this index */
-  int *aiColumn;   /* Which columns are used by this index.  1st is 0 */
-  tRowcnt *aiRowEst; /* Result of ANALYZE: Est. rows selected by each column */
-  Table *pTable;   /* The SQL table being indexed */
-  char *zColAff;   /* String defining the affinity of each column */
-  Index *pNext;    /* The next index associated with the same table */
-  Schema *pSchema; /* Schema containing this index */
-  u8 *aSortOrder;  /* Array of size Index.nColumn. True==DESC, False==ASC */
-  char **azColl;   /* Array of collation sequence names for index */
-  int nColumn;     /* Number of columns in the table used by this index */
-  int tnum;        /* Page containing root of this index in database file */
-  u8 onError;      /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
-  u8 autoIndex;    /* True if is automatically created (ex: by UNIQUE) */
-  u8 bUnordered;   /* Use this index for == or IN queries only */
+  char *zName;             /* Name of this index */
+  int *aiColumn;           /* Which columns are used by this index.  1st is 0 */
+  tRowcnt *aiRowEst;       /* From ANALYZE: Est. rows selected by each column */
+  Table *pTable;           /* The SQL table being indexed */
+  char *zColAff;           /* String defining the affinity of each column */
+  Index *pNext;            /* The next index associated with the same table */
+  Schema *pSchema;         /* Schema containing this index */
+  u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
+  char **azColl;           /* Array of collation sequence names for index */
+  Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
+  int tnum;                /* DB Page containing root of this index */
+  u16 nColumn;             /* Number of columns in table used by this index */
+  u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
+  unsigned autoIndex:2;    /* 1==UNIQUE, 2==PRIMARY KEY, 0==CREATE INDEX */
+  unsigned bUnordered:1;   /* Use this index for == or IN queries only */
+  unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
 #ifdef SQLITE_ENABLE_STAT3
   int nSample;             /* Number of elements in aSample[] */
   tRowcnt avgEq;           /* Average nEq value for key values not in aSample */
@@ -10644,13 +10952,15 @@ struct Expr {
     ExprList *pList;     /* Function arguments or in "<expr> IN (<expr-list)" */
     Select *pSelect;     /* Used for sub-selects and "<expr> IN (<select>)" */
   } x;
-  CollSeq *pColl;        /* The collation type of the column or 0 */
 
   /* If the EP_Reduced flag is set in the Expr.flags mask, then no
   ** space is allocated for the fields below this point. An attempt to
   ** access them will result in a segfault or malfunction.
   *********************************************************************/
 
+#if SQLITE_MAX_EXPR_DEPTH>0
+  int nHeight;           /* Height of the tree headed by this node */
+#endif
   int iTable;            /* TK_COLUMN: cursor number of table holding column
                          ** TK_REGISTER: register number
                          ** TK_TRIGGER: 1 -> new, 0 -> old */
@@ -10659,13 +10969,11 @@ struct Expr {
   i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
   i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
   u8 flags2;             /* Second set of flags.  EP2_... */
-  u8 op2;                /* If a TK_REGISTER, the original value of Expr.op */
-                         /* If TK_COLUMN, the value of p5 for OP_Column */
+  u8 op2;                /* TK_REGISTER: original value of Expr.op
+                         ** TK_COLUMN: the value of p5 for OP_Column
+                         ** TK_AGG_FUNCTION: nesting depth */
   AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
   Table *pTab;           /* Table for TK_COLUMN expressions. */
-#if SQLITE_MAX_EXPR_DEPTH>0
-  int nHeight;           /* Height of the tree headed by this node */
-#endif
 };
 
 /*
@@ -10679,7 +10987,7 @@ struct Expr {
 #define EP_VarSelect  0x0020  /* pSelect is correlated, not constant */
 #define EP_DblQuoted  0x0040  /* token.z was originally in "..." */
 #define EP_InfixFunc  0x0080  /* True for an infix function: LIKE, GLOB, etc */
-#define EP_ExpCollate 0x0100  /* Collating sequence specified explicitly */
+#define EP_Collate    0x0100  /* Tree contains a TK_COLLATE opeartor */
 #define EP_FixedDest  0x0200  /* Result needed in a specific register */
 #define EP_IntValue   0x0400  /* Integer value contained in u.iValue */
 #define EP_xIsSelect  0x0800  /* x.pSelect is valid (otherwise x.pList is) */
@@ -10737,18 +11045,27 @@ struct Expr {
 ** list of "ID = expr" items in an UPDATE.  A list of expressions can
 ** also be used as the argument to a function, in which case the a.zName
 ** field is not used.
+**
+** By default the Expr.zSpan field holds a human-readable description of
+** the expression that is used in the generation of error messages and
+** column labels.  In this case, Expr.zSpan is typically the text of a
+** column expression as it exists in a SELECT statement.  However, if
+** the bSpanIsTab flag is set, then zSpan is overloaded to mean the name
+** of the result column in the form: DATABASE.TABLE.COLUMN.  This later
+** form is used for name resolution with nested FROM clauses.
 */
 struct ExprList {
   int nExpr;             /* Number of expressions on the list */
   int iECursor;          /* VDBE Cursor associated with this ExprList */
   struct ExprList_item { /* For each expression in the list */
-    Expr *pExpr;           /* The list of expressions */
-    char *zName;           /* Token associated with this expression */
-    char *zSpan;           /* Original text of the expression */
-    u8 sortOrder;          /* 1 for DESC or 0 for ASC */
-    u8 done;               /* A flag to indicate when processing is finished */
-    u16 iOrderByCol;       /* For ORDER BY, column number in result set */
-    u16 iAlias;            /* Index into Parse.aAlias[] for zName */
+    Expr *pExpr;            /* The list of expressions */
+    char *zName;            /* Token associated with this expression */
+    char *zSpan;            /* Original text of the expression */
+    u8 sortOrder;           /* 1 for DESC or 0 for ASC */
+    unsigned done :1;       /* A flag to indicate when processing is finished */
+    unsigned bSpanIsTab :1; /* zSpan holds DB.TABLE.COLUMN */
+    u16 iOrderByCol;        /* For ORDER BY, column number in result set */
+    u16 iAlias;             /* Index into Parse.aAlias[] for zName */
   } *a;                  /* Alloc a power of two greater or equal to nExpr */
 };
 
@@ -10800,6 +11117,11 @@ typedef u64 Bitmask;
 */
 #define BMS  ((int)(sizeof(Bitmask)*8))
 
+/*
+** A bit in a Bitmask
+*/
+#define MASKBIT(n)   (((Bitmask)1)<<(n))
+
 /*
 ** The following structure describes the FROM clause of a SELECT statement.
 ** Each table or subquery in the FROM clause is a separate element of
@@ -10820,9 +11142,10 @@ typedef u64 Bitmask;
 ** contains more than 63 columns and the 64-th or later column is used.
 */
 struct SrcList {
-  i16 nSrc;        /* Number of tables or subqueries in the FROM clause */
-  i16 nAlloc;      /* Number of entries allocated in a[] below */
+  u8 nSrc;        /* Number of tables or subqueries in the FROM clause */
+  u8 nAlloc;      /* Number of entries allocated in a[] below */
   struct SrcList_item {
+    Schema *pSchema;  /* Schema to which this item is fixed */
     char *zDatabase;  /* Name of database holding this table */
     char *zName;      /* Name of the table */
     char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
@@ -10831,8 +11154,9 @@ struct SrcList {
     int addrFillSub;  /* Address of subroutine to manifest a subquery */
     int regReturn;    /* Register holding return address of addrFillSub */
     u8 jointype;      /* Type of join between this able and the previous */
-    u8 notIndexed;    /* True if there is a NOT INDEXED clause */
-    u8 isCorrelated;  /* True if sub-query is correlated */
+    unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
+    unsigned isCorrelated :1;  /* True if sub-query is correlated */
+    unsigned viaCoroutine :1;  /* Implemented as a co-routine */
 #ifndef SQLITE_OMIT_EXPLAIN
     u8 iSelectId;     /* If pSelect!=0, the id of the sub-select in EQP */
 #endif
@@ -10857,75 +11181,6 @@ struct SrcList {
 #define JT_ERROR     0x0040    /* unknown or unsupported join type */
 
 
-/*
-** A WherePlan object holds information that describes a lookup
-** strategy.
-**
-** This object is intended to be opaque outside of the where.c module.
-** It is included here only so that that compiler will know how big it
-** is.  None of the fields in this object should be used outside of
-** the where.c module.
-**
-** Within the union, pIdx is only used when wsFlags&WHERE_INDEXED is true.
-** pTerm is only used when wsFlags&WHERE_MULTI_OR is true.  And pVtabIdx
-** is only used when wsFlags&WHERE_VIRTUALTABLE is true.  It is never the
-** case that more than one of these conditions is true.
-*/
-struct WherePlan {
-  u32 wsFlags;                   /* WHERE_* flags that describe the strategy */
-  u32 nEq;                       /* Number of == constraints */
-  double nRow;                   /* Estimated number of rows (for EQP) */
-  union {
-    Index *pIdx;                   /* Index when WHERE_INDEXED is true */
-    struct WhereTerm *pTerm;       /* WHERE clause term for OR-search */
-    sqlite3_index_info *pVtabIdx;  /* Virtual table index to use */
-  } u;
-};
-
-/*
-** For each nested loop in a WHERE clause implementation, the WhereInfo
-** structure contains a single instance of this structure.  This structure
-** is intended to be private the the where.c module and should not be
-** access or modified by other modules.
-**
-** The pIdxInfo field is used to help pick the best index on a
-** virtual table.  The pIdxInfo pointer contains indexing
-** information for the i-th table in the FROM clause before reordering.
-** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
-** All other information in the i-th WhereLevel object for the i-th table
-** after FROM clause ordering.
-*/
-struct WhereLevel {
-  WherePlan plan;       /* query plan for this element of the FROM clause */
-  int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
-  int iTabCur;          /* The VDBE cursor used to access the table */
-  int iIdxCur;          /* The VDBE cursor used to access pIdx */
-  int addrBrk;          /* Jump here to break out of the loop */
-  int addrNxt;          /* Jump here to start the next IN combination */
-  int addrCont;         /* Jump here to continue with the next loop cycle */
-  int addrFirst;        /* First instruction of interior of the loop */
-  u8 iFrom;             /* Which entry in the FROM clause */
-  u8 op, p5;            /* Opcode and P5 of the opcode that ends the loop */
-  int p1, p2;           /* Operands of the opcode used to ends the loop */
-  union {               /* Information that depends on plan.wsFlags */
-    struct {
-      int nIn;              /* Number of entries in aInLoop[] */
-      struct InLoop {
-        int iCur;              /* The VDBE cursor used by this IN operator */
-        int addrInTop;         /* Top of the IN loop */
-      } *aInLoop;           /* Information about each nested IN operator */
-    } in;                 /* Used when plan.wsFlags&WHERE_IN_ABLE */
-  } u;
-
-  /* The following field is really not part of the current level.  But
-  ** we need a place to cache virtual table index information for each
-  ** virtual table in the FROM clause and the WhereLevel structure is
-  ** a convenient place since there is one WhereLevel for each FROM clause
-  ** element.
-  */
-  sqlite3_index_info *pIdxInfo;  /* Index info for n-th source table */
-};
-
 /*
 ** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
 ** and the WhereInfo.wctrlFlags member.
@@ -10939,33 +11194,16 @@ struct WhereLevel {
 #define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
 #define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
 #define WHERE_AND_ONLY         0x0080 /* Don't use indices for OR terms */
+#define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
+#define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
+#define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
 
-/*
-** The WHERE clause processing routine has two halves.  The
-** first part does the start of the WHERE loop and the second
-** half does the tail of the WHERE loop.  An instance of
-** this structure is returned by the first half and passed
-** into the second half to give some continuity.
+/* Allowed return values from sqlite3WhereIsDistinct()
 */
-struct WhereInfo {
-  Parse *pParse;       /* Parsing and code generating context */
-  u16 wctrlFlags;      /* Flags originally passed to sqlite3WhereBegin() */
-  u8 okOnePass;        /* Ok to use one-pass algorithm for UPDATE or DELETE */
-  u8 untestedTerms;    /* Not all WHERE terms resolved by outer loop */
-  u8 eDistinct;
-  SrcList *pTabList;             /* List of tables in the join */
-  int iTop;                      /* The very beginning of the WHERE loop */
-  int iContinue;                 /* Jump here to continue with next record */
-  int iBreak;                    /* Jump here to break out of the loop */
-  int nLevel;                    /* Number of nested loop */
-  struct WhereClause *pWC;       /* Decomposition of the WHERE clause */
-  double savedNQueryLoop;        /* pParse->nQueryLoop outside the WHERE loop */
-  double nRowOut;                /* Estimated number of output rows */
-  WhereLevel a[1];               /* Information about each nest loop in WHERE */
-};
-
-#define WHERE_DISTINCT_UNIQUE 1
-#define WHERE_DISTINCT_ORDERED 2
+#define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
+#define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
+#define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
+#define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */
 
 /*
 ** A NameContext defines a context in which to resolve table and column
@@ -10991,7 +11229,7 @@ struct WhereInfo {
 struct NameContext {
   Parse *pParse;       /* The parser */
   SrcList *pSrcList;   /* One or more tables used to resolve names */
-  ExprList *pEList;    /* Optional list of named expressions */
+  ExprList *pEList;    /* Optional list of result-set columns */
   AggInfo *pAggInfo;   /* Information about aggregates at this level */
   NameContext *pNext;  /* Next outer name context.  NULL for outermost */
   int nRef;            /* Number of names resolved by this context */
@@ -11006,6 +11244,7 @@ struct NameContext {
 #define NC_HasAgg    0x02    /* One or more aggregate functions seen */
 #define NC_IsCheck   0x04    /* True if resolving names in a CHECK constraint */
 #define NC_InAggFunc 0x08    /* True if analyzing arguments to an agg func */
+#define NC_PartIdx   0x10    /* True if resolving a partial index WHERE */
 
 /*
 ** An instance of the following structure contains all information
@@ -11024,17 +11263,16 @@ struct NameContext {
 ** as the OP_OpenEphm instruction is coded because not
 ** enough information about the compound query is known at that point.
 ** The KeyInfo for addrOpenTran[0] and [1] contains collating sequences
-** for the result set.  The KeyInfo for addrOpenTran[2] contains collating
+** for the result set.  The KeyInfo for addrOpenEphm[2] contains collating
 ** sequences for the ORDER BY clause.
 */
 struct Select {
   ExprList *pEList;      /* The fields of the result */
   u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
-  char affinity;         /* MakeRecord with this affinity for SRT_Set */
   u16 selFlags;          /* Various SF_* values */
   int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
   int addrOpenEphm[3];   /* OP_OpenEphem opcodes related to this select */
-  double nSelectRow;     /* Estimated number of result rows */
+  u64 nSelectRow;        /* Estimated number of result rows */
   SrcList *pSrc;         /* The FROM clause */
   Expr *pWhere;          /* The WHERE clause */
   ExprList *pGroupBy;    /* The GROUP BY clause */
@@ -11051,14 +11289,17 @@ struct Select {
 ** Allowed values for Select.selFlags.  The "SF" prefix stands for
 ** "Select Flag".
 */
-#define SF_Distinct        0x01  /* Output should be DISTINCT */
-#define SF_Resolved        0x02  /* Identifiers have been resolved */
-#define SF_Aggregate       0x04  /* Contains aggregate functions */
-#define SF_UsesEphemeral   0x08  /* Uses the OpenEphemeral opcode */
-#define SF_Expanded        0x10  /* sqlite3SelectExpand() called on this */
-#define SF_HasTypeInfo     0x20  /* FROM subqueries have Table metadata */
-#define SF_UseSorter       0x40  /* Sort using a sorter */
-#define SF_Values          0x80  /* Synthesized from VALUES clause */
+#define SF_Distinct        0x0001  /* Output should be DISTINCT */
+#define SF_Resolved        0x0002  /* Identifiers have been resolved */
+#define SF_Aggregate       0x0004  /* Contains aggregate functions */
+#define SF_UsesEphemeral   0x0008  /* Uses the OpenEphemeral opcode */
+#define SF_Expanded        0x0010  /* sqlite3SelectExpand() called on this */
+#define SF_HasTypeInfo     0x0020  /* FROM subqueries have Table metadata */
+#define SF_UseSorter       0x0040  /* Sort using a sorter */
+#define SF_Values          0x0080  /* Synthesized from VALUES clause */
+#define SF_Materialize     0x0100  /* Force materialization of views */
+#define SF_NestedFrom      0x0200  /* Part of a parenthesized FROM clause */
+#define SF_MaybeConvert    0x0400  /* Need convertCompoundSelectToSubquery() */
 
 
 /*
@@ -11081,16 +11322,15 @@ struct Select {
 #define SRT_Coroutine   10  /* Generate a single row of result */
 
 /*
-** A structure used to customize the behavior of sqlite3Select(). See
-** comments above sqlite3Select() for details.
+** An instance of this object describes where to put of the results of
+** a SELECT statement.
 */
-typedef struct SelectDest SelectDest;
 struct SelectDest {
-  u8 eDest;         /* How to dispose of the results */
-  u8 affinity;      /* Affinity used when eDest==SRT_Set */
-  int iParm;        /* A parameter used by the eDest disposal method */
-  int iMem;         /* Base register where results are written */
-  int nMem;         /* Number of registers allocated */
+  u8 eDest;         /* How to dispose of the results.  On of SRT_* above. */
+  char affSdst;     /* Affinity used when eDest==SRT_Set */
+  int iSDParm;      /* A parameter used by the eDest disposal method */
+  int iSdst;        /* Base register where results are written */
+  int nSdst;        /* Number of registers allocated */
 };
 
 /*
@@ -11181,6 +11421,7 @@ struct Parse {
   u8 iColCache;        /* Next entry in aColCache[] to replace */
   u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
   u8 mayAbort;         /* True if statement may throw an ABORT exception */
+  u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
   int aTempReg[8];     /* Holding area for temporary registers */
   int nRangeReg;       /* Size of the temporary register block */
   int iRangeReg;       /* First register in temporary register block */
@@ -11190,6 +11431,7 @@ struct Parse {
   int nSet;            /* Number of sets used so far */
   int nOnce;           /* Number of OP_Once instructions so far */
   int ckBase;          /* Base register of data during check constraints */
+  int iPartIdxTab;     /* Table corresponding to a partial index */
   int iCacheLevel;     /* ColCache valid when aColCache[].iLevel<=iCacheLevel */
   int iCacheCnt;       /* Counter used to generate aColCache[].lru values */
   struct yColCache {
@@ -11217,7 +11459,7 @@ struct Parse {
   /* Information used while coding trigger programs. */
   Parse *pToplevel;    /* Parse structure for main program (or NULL) */
   Table *pTriggerTab;  /* Table triggers are being coded for */
-  double nQueryLoop;   /* Estimated number of iterations of a query */
+  u32 nQueryLoop;      /* Est number of iterations of a query (10*log2(N)) */
   u32 oldmask;         /* Mask of old.* columns referenced */
   u32 newmask;         /* Mask of new.* columns referenced */
   u8 eTriggerOp;       /* TK_UPDATE, TK_INSERT or TK_DELETE */
@@ -11286,6 +11528,9 @@ struct AuthContext {
 #define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
 #define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
 #define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
+#define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
+#define OPFLAG_P2ISREG       0x02    /* P2 to OP_Open** is a register number */
+#define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
 
 /*
  * Each trigger present in the database schema is stored as an instance of
@@ -11385,6 +11630,7 @@ struct TriggerStep {
 typedef struct DbFixer DbFixer;
 struct DbFixer {
   Parse *pParse;      /* The parsing context.  Error messages written here */
+  Schema *pSchema;    /* Fix items to this schema */
   const char *zDb;    /* Make sure all objects are contained in this database */
   const char *zType;  /* Type of the container - used for error messages */
   const Token *pName; /* Name of the container - used for error messages */
@@ -11401,10 +11647,11 @@ struct StrAccum {
   int  nChar;          /* Length of the string so far */
   int  nAlloc;         /* Amount of space allocated in zText */
   int  mxAlloc;        /* Maximum allowed string length */
-  u8   mallocFailed;   /* Becomes true if any memory allocation fails */
   u8   useMalloc;      /* 0: none,  1: sqlite3DbMalloc,  2: sqlite3_malloc */
-  u8   tooBig;         /* Becomes true if string size exceeds limits */
+  u8   accError;       /* STRACCUM_NOMEM or STRACCUM_TOOBIG */
 };
+#define STRACCUM_NOMEM   1
+#define STRACCUM_TOOBIG  2
 
 /*
 ** A pointer to this structure is used to communicate information
@@ -11427,6 +11674,7 @@ struct Sqlite3Config {
   int bCoreMutex;                   /* True to enable core mutexing */
   int bFullMutex;                   /* True to enable full mutexing */
   int bOpenUri;                     /* True to interpret filenames as URIs */
+  int bUseCis;                      /* Use covering indices for full-scans */
   int mxStrlen;                     /* Maximum string length */
   int szLookaside;                  /* Default lookaside buffer size */
   int nLookaside;                   /* Default lookaside buffer count */
@@ -11436,6 +11684,8 @@ struct Sqlite3Config {
   void *pHeap;                      /* Heap storage space */
   int nHeap;                        /* Size of pHeap[] */
   int mnReq, mxReq;                 /* Min and max heap requests sizes */
+  sqlite3_int64 szMmap;             /* mmap() space per open file */
+  sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
   void *pScratch;                   /* Scratch memory */
   int szScratch;                    /* Size of each scratch buffer */
   int nScratch;                     /* Number of scratch buffers */
@@ -11456,6 +11706,10 @@ struct Sqlite3Config {
   void (*xLog)(void*,int,const char*); /* Function for logging */
   void *pLogArg;                       /* First argument to xLog() */
   int bLocaltimeFault;              /* True to fail localtime() calls */
+#ifdef SQLITE_ENABLE_SQLLOG
+  void(*xSqllog)(void*,sqlite3*,const char*, int);
+  void *pSqllogArg;
+#endif
 };
 
 /*
@@ -11465,10 +11719,13 @@ struct Walker {
   int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
   int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
   Parse *pParse;                            /* Parser context.  */
+  int walkerDepth;                          /* Number of subqueries */
+  u8 bSelectDepthFirst;                     /* Do subqueries first */
   union {                                   /* Extra data for callback */
     NameContext *pNC;                          /* Naming context */
     int i;                                     /* Integer value */
     SrcList *pSrcList;                         /* FROM clause */
+    struct SrcCount *pSrcCount;                /* Counting column references */
   } u;
 };
 
@@ -11741,6 +11998,7 @@ SQLITE_PRIVATE   void sqlite3AutoincrementEnd(Parse *pParse);
 # define sqlite3AutoincrementBegin(X)
 # define sqlite3AutoincrementEnd(X)
 #endif
+SQLITE_PRIVATE int sqlite3CodeCoroutine(Parse*, Select*, SelectDest*);
 SQLITE_PRIVATE void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
 SQLITE_PRIVATE void *sqlite3ArrayAllocate(sqlite3*,void*,int,int*,int*);
 SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
@@ -11756,26 +12014,31 @@ SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse*, SrcList*);
 SQLITE_PRIVATE void sqlite3IdListDelete(sqlite3*, IdList*);
 SQLITE_PRIVATE void sqlite3SrcListDelete(sqlite3*, SrcList*);
 SQLITE_PRIVATE Index *sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
-                        Token*, int, int);
+                          Expr*, int, int);
 SQLITE_PRIVATE void sqlite3DropIndex(Parse*, SrcList*, int);
 SQLITE_PRIVATE int sqlite3Select(Parse*, Select*, SelectDest*);
 SQLITE_PRIVATE Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
-                         Expr*,ExprList*,int,Expr*,Expr*);
+                         Expr*,ExprList*,u16,Expr*,Expr*);
 SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3*, Select*);
 SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse*, SrcList*);
 SQLITE_PRIVATE int sqlite3IsReadOnly(Parse*, Table*, int);
 SQLITE_PRIVATE void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
 #if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
-SQLITE_PRIVATE Expr *sqlite3LimitWhere(Parse *, SrcList *, Expr *, ExprList *, Expr *, Expr *, char *);
+SQLITE_PRIVATE Expr *sqlite3LimitWhere(Parse*,SrcList*,Expr*,ExprList*,Expr*,Expr*,char*);
 #endif
 SQLITE_PRIVATE void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
 SQLITE_PRIVATE void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
-SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**,ExprList*,u16);
+SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
 SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo*);
+SQLITE_PRIVATE u64 sqlite3WhereOutputRowCount(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereIsDistinct(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereIsOrdered(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereContinueLabel(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereBreakLabel(WhereInfo*);
+SQLITE_PRIVATE int sqlite3WhereOkOnePass(WhereInfo*);
 SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
 SQLITE_PRIVATE void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
 SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse*, int, int, int);
-SQLITE_PRIVATE void sqlite3ExprCodeCopy(Parse*, int, int, int);
 SQLITE_PRIVATE void sqlite3ExprCacheStore(Parse*, int, int, int);
 SQLITE_PRIVATE void sqlite3ExprCachePush(Parse*);
 SQLITE_PRIVATE void sqlite3ExprCachePop(Parse*, int);
@@ -11792,16 +12055,19 @@ SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse*, Expr*, int, int);
 SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse*, Expr*, int, int);
 SQLITE_PRIVATE Table *sqlite3FindTable(sqlite3*,const char*, const char*);
 SQLITE_PRIVATE Table *sqlite3LocateTable(Parse*,int isView,const char*, const char*);
+SQLITE_PRIVATE Table *sqlite3LocateTableItem(Parse*,int isView,struct SrcList_item *);
 SQLITE_PRIVATE Index *sqlite3FindIndex(sqlite3*,const char*, const char*);
 SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTable(sqlite3*,int,const char*);
 SQLITE_PRIVATE void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
 SQLITE_PRIVATE void sqlite3Vacuum(Parse*);
 SQLITE_PRIVATE int sqlite3RunVacuum(char**, sqlite3*);
 SQLITE_PRIVATE char *sqlite3NameFromToken(sqlite3*, Token*);
-SQLITE_PRIVATE int sqlite3ExprCompare(Expr*, Expr*);
-SQLITE_PRIVATE int sqlite3ExprListCompare(ExprList*, ExprList*);
+SQLITE_PRIVATE int sqlite3ExprCompare(Expr*, Expr*, int);
+SQLITE_PRIVATE int sqlite3ExprListCompare(ExprList*, ExprList*, int);
+SQLITE_PRIVATE int sqlite3ExprImpliesExpr(Expr*, Expr*, int);
 SQLITE_PRIVATE void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
 SQLITE_PRIVATE void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
+SQLITE_PRIVATE int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
 SQLITE_PRIVATE Vdbe *sqlite3GetVdbe(Parse*);
 SQLITE_PRIVATE void sqlite3PrngSaveState(void);
 SQLITE_PRIVATE void sqlite3PrngRestoreState(void);
@@ -11814,6 +12080,7 @@ SQLITE_PRIVATE void sqlite3CommitTransaction(Parse*);
 SQLITE_PRIVATE void sqlite3RollbackTransaction(Parse*);
 SQLITE_PRIVATE void sqlite3Savepoint(Parse*, int, Token*);
 SQLITE_PRIVATE void sqlite3CloseSavepoints(sqlite3 *);
+SQLITE_PRIVATE void sqlite3LeaveMutexAndCloseZombie(sqlite3*);
 SQLITE_PRIVATE int sqlite3ExprIsConstant(Expr*);
 SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr*);
 SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr*);
@@ -11824,7 +12091,7 @@ SQLITE_PRIVATE int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
 SQLITE_PRIVATE int sqlite3IsRowid(const char*);
 SQLITE_PRIVATE void sqlite3GenerateRowDelete(Parse*, Table*, int, int, int, Trigger *, int);
 SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int*);
-SQLITE_PRIVATE int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int);
+SQLITE_PRIVATE int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*);
 SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(Parse*,Table*,int,int,
                                      int*,int,int,int,int,int*);
 SQLITE_PRIVATE void sqlite3CompleteInsertion(Parse*, Table*, int, int, int*, int, int, int);
@@ -11832,7 +12099,7 @@ SQLITE_PRIVATE int sqlite3OpenTableAndIndices(Parse*, Table*, int, int);
 SQLITE_PRIVATE void sqlite3BeginWriteOperation(Parse*, int, int);
 SQLITE_PRIVATE void sqlite3MultiWrite(Parse*);
 SQLITE_PRIVATE void sqlite3MayAbort(Parse*);
-SQLITE_PRIVATE void sqlite3HaltConstraint(Parse*, int, char*, int);
+SQLITE_PRIVATE void sqlite3HaltConstraint(Parse*, int, int, char*, int);
 SQLITE_PRIVATE Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
 SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
 SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
@@ -11913,7 +12180,7 @@ SQLITE_PRIVATE int sqlite3GetInt32(const char *, int*);
 SQLITE_PRIVATE int sqlite3Atoi(const char*);
 SQLITE_PRIVATE int sqlite3Utf16ByteLen(const void *pData, int nChar);
 SQLITE_PRIVATE int sqlite3Utf8CharLen(const char *pData, int nByte);
-SQLITE_PRIVATE u32 sqlite3Utf8Read(const u8*, const u8**);
+SQLITE_PRIVATE u32 sqlite3Utf8Read(const u8**);
 
 /*
 ** Routines to read and write variable-length integers.  These used to
@@ -11945,8 +12212,11 @@ SQLITE_PRIVATE int sqlite3VarintLen(u64 v);
 **     x = putVarint32( A, B );
 **
 */
-#define getVarint32(A,B)  (u8)((*(A)<(u8)0x80) ? ((B) = (u32)*(A)),1 : sqlite3GetVarint32((A), (u32 *)&(B)))
-#define putVarint32(A,B)  (u8)(((u32)(B)<(u32)0x80) ? (*(A) = (unsigned char)(B)),1 : sqlite3PutVarint32((A), (B)))
+#define getVarint32(A,B)  \
+  (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
+#define putVarint32(A,B)  \
+  (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
+  sqlite3PutVarint32((A),(B)))
 #define getVarint    sqlite3GetVarint
 #define putVarint    sqlite3PutVarint
 
@@ -11961,13 +12231,20 @@ SQLITE_PRIVATE void sqlite3Error(sqlite3*, int, const char*,...);
 SQLITE_PRIVATE void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
 SQLITE_PRIVATE u8 sqlite3HexToInt(int h);
 SQLITE_PRIVATE int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);
+
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST) || \
+    defined(SQLITE_DEBUG_OS_TRACE)
+SQLITE_PRIVATE const char *sqlite3ErrName(int);
+#endif
+
 SQLITE_PRIVATE const char *sqlite3ErrStr(int);
 SQLITE_PRIVATE int sqlite3ReadSchema(Parse *pParse);
 SQLITE_PRIVATE CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int);
 SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName);
 SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr);
-SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Expr*, CollSeq*);
-SQLITE_PRIVATE Expr *sqlite3ExprSetCollByToken(Parse *pParse, Expr*, Token*);
+SQLITE_PRIVATE Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, Token*);
+SQLITE_PRIVATE Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*);
+SQLITE_PRIVATE Expr *sqlite3ExprSkipCollate(Expr*);
 SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *, CollSeq *);
 SQLITE_PRIVATE int sqlite3CheckObjectName(Parse *, const char *);
 SQLITE_PRIVATE void sqlite3VdbeSetChanges(sqlite3 *, int);
@@ -12014,13 +12291,15 @@ SQLITE_PRIVATE void sqlite3NestedParse(Parse*, const char*, ...);
 SQLITE_PRIVATE void sqlite3ExpirePreparedStatements(sqlite3*);
 SQLITE_PRIVATE int sqlite3CodeSubselect(Parse *, Expr *, int, int);
 SQLITE_PRIVATE void sqlite3SelectPrep(Parse*, Select*, NameContext*);
+SQLITE_PRIVATE int sqlite3MatchSpanName(const char*, const char*, const char*, const char*);
 SQLITE_PRIVATE int sqlite3ResolveExprNames(NameContext*, Expr*);
 SQLITE_PRIVATE void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
+SQLITE_PRIVATE void sqlite3ResolveSelfReference(Parse*,Table*,int,Expr*,ExprList*);
 SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
 SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int, int);
 SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *, Token *);
 SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *, SrcList *);
-SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(sqlite3*, u8, CollSeq *, const char*);
+SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(Parse*, u8, CollSeq *, const char*);
 SQLITE_PRIVATE char sqlite3AffinityType(const char*);
 SQLITE_PRIVATE void sqlite3Analyze(Parse*, Token*, Token*);
 SQLITE_PRIVATE int sqlite3InvokeBusyHandler(BusyHandler*);
@@ -12035,6 +12314,7 @@ SQLITE_PRIVATE void sqlite3MinimumFileFormat(Parse*, int, int);
 SQLITE_PRIVATE void sqlite3SchemaClear(void *);
 SQLITE_PRIVATE Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
 SQLITE_PRIVATE int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int);
 SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *, Index *);
 SQLITE_PRIVATE int sqlite3CreateFunc(sqlite3 *, const char *, int, int, void *, 
   void (*)(sqlite3_context*,int,sqlite3_value **),
@@ -12096,13 +12376,14 @@ SQLITE_PRIVATE   int sqlite3Utf8To8(unsigned char*);
 #else
 SQLITE_PRIVATE    void sqlite3VtabClear(sqlite3 *db, Table*);
 SQLITE_PRIVATE    void sqlite3VtabDisconnect(sqlite3 *db, Table *p);
-SQLITE_PRIVATE    int sqlite3VtabSync(sqlite3 *db, char **);
+SQLITE_PRIVATE    int sqlite3VtabSync(sqlite3 *db, Vdbe*);
 SQLITE_PRIVATE    int sqlite3VtabRollback(sqlite3 *db);
 SQLITE_PRIVATE    int sqlite3VtabCommit(sqlite3 *db);
 SQLITE_PRIVATE    void sqlite3VtabLock(VTable *);
 SQLITE_PRIVATE    void sqlite3VtabUnlock(VTable *);
 SQLITE_PRIVATE    void sqlite3VtabUnlockList(sqlite3*);
 SQLITE_PRIVATE    int sqlite3VtabSavepoint(sqlite3 *, int, int);
+SQLITE_PRIVATE    void sqlite3VtabImportErrmsg(Vdbe*, sqlite3_vtab*);
 SQLITE_PRIVATE    VTable *sqlite3GetVTable(sqlite3*, Table*);
 #  define sqlite3VtabInSync(db) ((db)->nVTrans>0 && (db)->aVTrans==0)
 #endif
@@ -12124,8 +12405,10 @@ SQLITE_PRIVATE void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
 SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(Parse *, Expr *, Expr *);
 SQLITE_PRIVATE int sqlite3TempInMemory(const sqlite3*);
 SQLITE_PRIVATE const char *sqlite3JournalModename(int);
-SQLITE_PRIVATE int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
-SQLITE_PRIVATE int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
+#ifndef SQLITE_OMIT_WAL
+SQLITE_PRIVATE   int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
+SQLITE_PRIVATE   int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
+#endif
 
 /* Declarations for functions in fkey.c. All of these are replaced by
 ** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
@@ -12150,8 +12433,10 @@ SQLITE_PRIVATE   FKey *sqlite3FkReferences(Table *);
 #endif
 #ifndef SQLITE_OMIT_FOREIGN_KEY
 SQLITE_PRIVATE   void sqlite3FkDelete(sqlite3 *, Table*);
+SQLITE_PRIVATE   int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
 #else
   #define sqlite3FkDelete(a,b)
+  #define sqlite3FkLocateIndex(a,b,c,d,e)
 #endif
 
 
@@ -12176,15 +12461,18 @@ SQLITE_PRIVATE   void sqlite3EndBenignMalloc(void);
 
 #define IN_INDEX_ROWID           1
 #define IN_INDEX_EPH             2
-#define IN_INDEX_INDEX           3
+#define IN_INDEX_INDEX_ASC       3
+#define IN_INDEX_INDEX_DESC      4
 SQLITE_PRIVATE int sqlite3FindInIndex(Parse *, Expr *, int*);
 
 #ifdef SQLITE_ENABLE_ATOMIC_WRITE
 SQLITE_PRIVATE   int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
 SQLITE_PRIVATE   int sqlite3JournalSize(sqlite3_vfs *);
 SQLITE_PRIVATE   int sqlite3JournalCreate(sqlite3_file *);
+SQLITE_PRIVATE   int sqlite3JournalExists(sqlite3_file *p);
 #else
   #define sqlite3JournalSize(pVfs) ((pVfs)->szOsFile)
+  #define sqlite3JournalExists(p) 1
 #endif
 
 SQLITE_PRIVATE void sqlite3MemJournalOpen(sqlite3_file *);
@@ -12413,6 +12701,10 @@ SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[256] = {
 # define  SQLITE_USE_URI 0
 #endif
 
+#ifndef SQLITE_ALLOW_COVERING_INDEX_SCAN
+# define SQLITE_ALLOW_COVERING_INDEX_SCAN 1
+#endif
+
 /*
 ** The following singleton contains the global configuration for
 ** the SQLite library.
@@ -12422,6 +12714,7 @@ SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config = {
    1,                         /* bCoreMutex */
    SQLITE_THREADSAFE==1,      /* bFullMutex */
    SQLITE_USE_URI,            /* bOpenUri */
+   SQLITE_ALLOW_COVERING_INDEX_SCAN,   /* bUseCis */
    0x7ffffffe,                /* mxStrlen */
    128,                       /* szLookaside */
    500,                       /* nLookaside */
@@ -12431,6 +12724,8 @@ SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config = {
    (void*)0,                  /* pHeap */
    0,                         /* nHeap */
    0, 0,                      /* mnHeap, mxHeap */
+   SQLITE_DEFAULT_MMAP_SIZE,  /* szMmap */
+   SQLITE_MAX_MMAP_SIZE,      /* mxMmap */
    (void*)0,                  /* pScratch */
    0,                         /* szScratch */
    0,                         /* nScratch */
@@ -12450,6 +12745,10 @@ SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config = {
    0,                         /* xLog */
    0,                         /* pLogArg */
    0,                         /* bLocaltimeFault */
+#ifdef SQLITE_ENABLE_SQLLOG
+   0,                         /* xSqllog */
+   0                          /* pSqllogArg */
+#endif
 };
 
 
@@ -12550,15 +12849,15 @@ static const char * const azCompileOpt[] = {
 #ifdef SQLITE_COVERAGE_TEST
   "COVERAGE_TEST",
 #endif
-#ifdef SQLITE_CURDIR
-  "CURDIR",
-#endif
 #ifdef SQLITE_DEBUG
   "DEBUG",
 #endif
 #ifdef SQLITE_DEFAULT_LOCKING_MODE
   "DEFAULT_LOCKING_MODE=" CTIMEOPT_VAL(SQLITE_DEFAULT_LOCKING_MODE),
 #endif
+#if defined(SQLITE_DEFAULT_MMAP_SIZE) && !defined(SQLITE_DEFAULT_MMAP_SIZE_xc)
+  "DEFAULT_MMAP_SIZE=" CTIMEOPT_VAL(SQLITE_DEFAULT_MMAP_SIZE),
+#endif
 #ifdef SQLITE_DISABLE_DIRSYNC
   "DISABLE_DIRSYNC",
 #endif
@@ -12649,6 +12948,9 @@ static const char * const azCompileOpt[] = {
 #ifdef SQLITE_LOCK_TRACE
   "LOCK_TRACE",
 #endif
+#if defined(SQLITE_MAX_MMAP_SIZE) && !defined(SQLITE_MAX_MMAP_SIZE_xc)
+  "MAX_MMAP_SIZE=" CTIMEOPT_VAL(SQLITE_MAX_MMAP_SIZE),
+#endif
 #ifdef SQLITE_MAX_SCHEMA_RETRY
   "MAX_SCHEMA_RETRY=" CTIMEOPT_VAL(SQLITE_MAX_SCHEMA_RETRY),
 #endif
@@ -12706,11 +13008,6 @@ static const char * const azCompileOpt[] = {
 #ifdef SQLITE_OMIT_CHECK
   "OMIT_CHECK",
 #endif
-/* // redundant
-** #ifdef SQLITE_OMIT_COMPILEOPTION_DIAGS
-**   "OMIT_COMPILEOPTION_DIAGS",
-** #endif
-*/
 #ifdef SQLITE_OMIT_COMPLETE
   "OMIT_COMPLETE",
 #endif
@@ -12765,9 +13062,6 @@ static const char * const azCompileOpt[] = {
 #ifdef SQLITE_OMIT_MEMORYDB
   "OMIT_MEMORYDB",
 #endif
-#ifdef SQLITE_OMIT_MERGE_SORT
-  "OMIT_MERGE_SORT",
-#endif
 #ifdef SQLITE_OMIT_OR_OPTIMIZATION
   "OMIT_OR_OPTIMIZATION",
 #endif
@@ -12840,6 +13134,9 @@ static const char * const azCompileOpt[] = {
 #ifdef SQLITE_PROXY_DEBUG
   "PROXY_DEBUG",
 #endif
+#ifdef SQLITE_RTREE_INT_ONLY
+  "RTREE_INT_ONLY",
+#endif
 #ifdef SQLITE_SECURE_DELETE
   "SECURE_DELETE",
 #endif
@@ -12852,13 +13149,13 @@ static const char * const azCompileOpt[] = {
 #ifdef SQLITE_TCL
   "TCL",
 #endif
-#ifdef SQLITE_TEMP_STORE
+#if defined(SQLITE_TEMP_STORE) && !defined(SQLITE_TEMP_STORE_xc)
   "TEMP_STORE=" CTIMEOPT_VAL(SQLITE_TEMP_STORE),
 #endif
 #ifdef SQLITE_TEST
   "TEST",
 #endif
-#ifdef SQLITE_THREADSAFE
+#if defined(SQLITE_THREADSAFE)
   "THREADSAFE=" CTIMEOPT_VAL(SQLITE_THREADSAFE),
 #endif
 #ifdef SQLITE_USE_ALLOCA
@@ -12884,8 +13181,11 @@ SQLITE_API int sqlite3_compileoption_used(const char *zOptName){
   /* Since ArraySize(azCompileOpt) is normally in single digits, a
   ** linear search is adequate.  No need for a binary search. */
   for(i=0; i<ArraySize(azCompileOpt); i++){
-    if(   (sqlite3StrNICmp(zOptName, azCompileOpt[i], n)==0)
-       && ( (azCompileOpt[i][n]==0) || (azCompileOpt[i][n]=='=') ) ) return 1;
+    if( sqlite3StrNICmp(zOptName, azCompileOpt[i], n)==0
+     && sqlite3CtypeMap[(unsigned char)azCompileOpt[i][n]]==0
+    ){
+      return 1;
+    }
   }
   return 0;
 }
@@ -12942,6 +13242,14 @@ SQLITE_API const char *sqlite3_compileoption_get(int N){
 #ifndef _VDBEINT_H_
 #define _VDBEINT_H_
 
+/*
+** The maximum number of times that a statement will try to reparse
+** itself before giving up and returning SQLITE_SCHEMA.
+*/
+#ifndef SQLITE_MAX_SCHEMA_RETRY
+# define SQLITE_MAX_SCHEMA_RETRY 50
+#endif
+
 /*
 ** SQL is translated into a sequence of instructions to be
 ** executed by a virtual machine.  Each instruction is an instance
@@ -12960,6 +13268,9 @@ typedef struct VdbeSorter VdbeSorter;
 /* Opaque type used by the explainer */
 typedef struct Explain Explain;
 
+/* Elements of the linked list at Vdbe.pAuxData */
+typedef struct AuxData AuxData;
+
 /*
 ** A cursor is a pointer into a single BTree within a database file.
 ** The cursor can seek to a BTree entry with a particular key, or
@@ -12987,6 +13298,7 @@ struct VdbeCursor {
   Bool isIndex;         /* True if an index containing keys only - no data */
   Bool isOrdered;       /* True if the underlying table is BTREE_UNORDERED */
   Bool isSorter;        /* True if a new-style sorter */
+  Bool multiPseudo;     /* Multi-register pseudo-cursor */
   sqlite3_vtab_cursor *pVtabCursor;  /* The cursor for a virtual table */
   const sqlite3_module *pModule;     /* Module for cursor pVtabCursor */
   i64 seqCount;         /* Sequence counter */
@@ -13046,7 +13358,7 @@ struct VdbeFrame {
   VdbeCursor **apCsr;     /* Array of Vdbe cursors for parent frame */
   void *token;            /* Copy of SubProgram.token */
   i64 lastRowid;          /* Last insert rowid (sqlite3.lastRowid) */
-  u16 nCursor;            /* Number of entries in apCsr */
+  int nCursor;            /* Number of entries in apCsr */
   int pc;                 /* Program Counter in parent (calling) frame */
   int nOp;                /* Size of aOp array */
   int nMem;               /* Number of entries in aMem */
@@ -13111,7 +13423,9 @@ struct Mem {
 #define MEM_RowSet    0x0020   /* Value is a RowSet object */
 #define MEM_Frame     0x0040   /* Value is a VdbeFrame object */
 #define MEM_Invalid   0x0080   /* Value is undefined */
-#define MEM_TypeMask  0x00ff   /* Mask of type bits */
+#define MEM_Cleared   0x0100   /* NULL set by OP_Null, not from data */
+#define MEM_TypeMask  0x01ff   /* Mask of type bits */
+
 
 /* Whenever Mem contains a valid string or blob representation, one of
 ** the following flags must be set to determine the memory management
@@ -13143,23 +13457,19 @@ struct Mem {
 #define memIsValid(M)  ((M)->flags & MEM_Invalid)==0
 #endif
 
-
-/* A VdbeFunc is just a FuncDef (defined in sqliteInt.h) that contains
-** additional information about auxiliary information bound to arguments
-** of the function.  This is used to implement the sqlite3_get_auxdata()
-** and sqlite3_set_auxdata() APIs.  The "auxdata" is some auxiliary data
-** that can be associated with a constant argument to a function.  This
-** allows functions such as "regexp" to compile their constant regular
-** expression argument once and reused the compiled code for multiple
-** invocations.
+/*
+** Each auxilliary data pointer stored by a user defined function 
+** implementation calling sqlite3_set_auxdata() is stored in an instance
+** of this structure. All such structures associated with a single VM
+** are stored in a linked list headed at Vdbe.pAuxData. All are destroyed
+** when the VM is halted (if not before).
 */
-struct VdbeFunc {
-  FuncDef *pFunc;               /* The definition of the function */
-  int nAux;                     /* Number of entries allocated for apAux[] */
-  struct AuxData {
-    void *pAux;                   /* Aux data for the i-th argument */
-    void (*xDelete)(void *);      /* Destructor for the aux data */
-  } apAux[1];                   /* One slot for each function argument */
+struct AuxData {
+  int iOp;                        /* Instruction number of OP_Function opcode */
+  int iArg;                       /* Index of function argument. */
+  void *pAux;                     /* Aux data pointer */
+  void (*xDelete)(void *);        /* Destructor for the aux data */
+  AuxData *pNext;                 /* Next element in list */
 };
 
 /*
@@ -13177,12 +13487,14 @@ struct VdbeFunc {
 */
 struct sqlite3_context {
   FuncDef *pFunc;       /* Pointer to function information.  MUST BE FIRST */
-  VdbeFunc *pVdbeFunc;  /* Auxilary data, if created. */
   Mem s;                /* The return value is stored here */
   Mem *pMem;            /* Memory cell used to store aggregate context */
   CollSeq *pColl;       /* Collating sequence */
+  Vdbe *pVdbe;          /* The VM that owns this context */
+  int iOp;              /* Instruction number of OP_Function */
   int isError;          /* Error code returned by the function. */
-  int skipFlag;         /* Skip skip accumulator loading if true */
+  u8 skipFlag;          /* Skip skip accumulator loading if true */
+  u8 fErrorOrAux;       /* isError!=0 or pVdbe->pAuxData modified */
 };
 
 /*
@@ -13197,6 +13509,11 @@ struct Explain {
   char zBase[100];   /* Initial space */
 };
 
+/* A bitfield type for use inside of structures.  Always follow with :N where
+** N is the number of bits.
+*/
+typedef unsigned bft;  /* Bit Field Type */
+
 /*
 ** An instance of the virtual machine.  This structure contains the complete
 ** state of the virtual machine.
@@ -13225,7 +13542,7 @@ struct Vdbe {
   int nLabel;             /* Number of labels used */
   int *aLabel;            /* Space to hold the labels */
   u16 nResColumn;         /* Number of columns in one row of the result set */
-  u16 nCursor;            /* Number of slots in apCsr[] */
+  int nCursor;            /* Number of slots in apCsr[] */
   u32 magic;              /* Magic number for sanity checking */
   char *zErrMsg;          /* Error message written here */
   Vdbe *pPrev,*pNext;     /* Linked list of VDBEs with the same Vdbe.db */
@@ -13238,25 +13555,28 @@ struct Vdbe {
   int pc;                 /* The program counter */
   int rc;                 /* Value to return */
   u8 errorAction;         /* Recovery action to do in case of an error */
-  u8 explain;             /* True if EXPLAIN present on SQL command */
-  u8 changeCntOn;         /* True to update the change-counter */
-  u8 expired;             /* True if the VM needs to be recompiled */
-  u8 runOnlyOnce;         /* Automatically expire on reset */
   u8 minWriteFileFormat;  /* Minimum file format for writable database files */
-  u8 inVtabMethod;        /* See comments above */
-  u8 usesStmtJournal;     /* True if uses a statement journal */
-  u8 readOnly;            /* True for read-only statements */
-  u8 isPrepareV2;         /* True if prepared with prepare_v2() */
+  bft explain:2;          /* True if EXPLAIN present on SQL command */
+  bft inVtabMethod:2;     /* See comments above */
+  bft changeCntOn:1;      /* True to update the change-counter */
+  bft expired:1;          /* True if the VM needs to be recompiled */
+  bft runOnlyOnce:1;      /* Automatically expire on reset */
+  bft usesStmtJournal:1;  /* True if uses a statement journal */
+  bft readOnly:1;         /* True for statements that do not write */
+  bft bIsReader:1;        /* True for statements that read */
+  bft isPrepareV2:1;      /* True if prepared with prepare_v2() */
+  bft doingRerun:1;       /* True if rerunning after an auto-reprepare */
   int nChange;            /* Number of db changes made since last reset */
   yDbMask btreeMask;      /* Bitmask of db->aDb[] entries referenced */
   yDbMask lockMask;       /* Subset of btreeMask that requires a lock */
   int iStatement;         /* Statement number (or 0 if has not opened stmt) */
-  int aCounter[3];        /* Counters used by sqlite3_stmt_status() */
+  u32 aCounter[5];        /* Counters used by sqlite3_stmt_status() */
 #ifndef SQLITE_OMIT_TRACE
   i64 startTime;          /* Time when query started - used for profiling */
 #endif
   i64 nFkConstraint;      /* Number of imm. FK constraints this VM */
   i64 nStmtDefCons;       /* Number of def. constraints when stmt started */
+  i64 nStmtDefImmCons;    /* Number of def. imm constraints when stmt started */
   char *zSql;             /* Text of the SQL statement that generated this */
   void *pFree;            /* Free this when deleting the vdbe */
 #ifdef SQLITE_DEBUG
@@ -13273,6 +13593,7 @@ struct Vdbe {
   SubProgram *pProgram;   /* Linked list of all sub-programs used by VM */
   int nOnceFlag;          /* Size of array aOnceFlag[] */
   u8 *aOnceFlag;          /* Flags for OP_Once */
+  AuxData *pAuxData;      /* Linked list of auxdata allocations */
 };
 
 /*
@@ -13296,7 +13617,7 @@ SQLITE_PRIVATE u32 sqlite3VdbeSerialTypeLen(u32);
 SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem*, int);
 SQLITE_PRIVATE u32 sqlite3VdbeSerialPut(unsigned char*, int, Mem*, int);
 SQLITE_PRIVATE u32 sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
-SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc*, int);
+SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(Vdbe*, int, int);
 
 int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
 SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(VdbeCursor*,UnpackedRecord*,int*);
@@ -13344,23 +13665,13 @@ SQLITE_PRIVATE int sqlite3VdbeFrameRestore(VdbeFrame *);
 SQLITE_PRIVATE void sqlite3VdbeMemStoreType(Mem *pMem);
 SQLITE_PRIVATE int sqlite3VdbeTransferError(Vdbe *p);
 
-#ifdef SQLITE_OMIT_MERGE_SORT
-# define sqlite3VdbeSorterInit(Y,Z)      SQLITE_OK
-# define sqlite3VdbeSorterWrite(X,Y,Z)   SQLITE_OK
-# define sqlite3VdbeSorterClose(Y,Z)
-# define sqlite3VdbeSorterRowkey(Y,Z)    SQLITE_OK
-# define sqlite3VdbeSorterRewind(X,Y,Z)  SQLITE_OK
-# define sqlite3VdbeSorterNext(X,Y,Z)    SQLITE_OK
-# define sqlite3VdbeSorterCompare(X,Y,Z) SQLITE_OK
-#else
 SQLITE_PRIVATE int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
 SQLITE_PRIVATE void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
-SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(VdbeCursor *, Mem *);
-SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *, VdbeCursor *, int *);
-SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *, VdbeCursor *, int *);
-SQLITE_PRIVATE int sqlite3VdbeSorterWrite(sqlite3 *, VdbeCursor *, Mem *);
-SQLITE_PRIVATE int sqlite3VdbeSorterCompare(VdbeCursor *, Mem *, int *);
-#endif
+SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
+SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *, int *);
+SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *, const VdbeCursor *, int *);
+SQLITE_PRIVATE int sqlite3VdbeSorterWrite(sqlite3 *, const VdbeCursor *, Mem *);
+SQLITE_PRIVATE int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int *);
 
 #if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
 SQLITE_PRIVATE   void sqlite3VdbeEnter(Vdbe*);
@@ -13592,7 +13903,8 @@ SQLITE_API int sqlite3_db_status(
 
       db->pnBytesFreed = &nByte;
       for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
-        sqlite3VdbeDeleteObject(db, pVdbe);
+        sqlite3VdbeClearObject(db, pVdbe);
+        sqlite3DbFree(db, pVdbe);
       }
       db->pnBytesFreed = 0;
 
@@ -13626,6 +13938,16 @@ SQLITE_API int sqlite3_db_status(
       break;
     }
 
+    /* Set *pCurrent to non-zero if there are unresolved deferred foreign
+    ** key constraints.  Set *pCurrent to zero if all foreign key constraints
+    ** have been satisfied.  The *pHighwater is always set to zero.
+    */
+    case SQLITE_DBSTATUS_DEFERRED_FKS: {
+      *pHighwater = 0;
+      *pCurrent = db->nDeferredImmCons>0 || db->nDeferredCons>0;
+      break;
+    }
+
     default: {
       rc = SQLITE_ERROR;
     }
@@ -14908,6 +15230,26 @@ SQLITE_PRIVATE int sqlite3OsShmMap(
   return id->pMethods->xShmMap(id, iPage, pgsz, bExtend, pp);
 }
 
+#if SQLITE_MAX_MMAP_SIZE>0
+/* The real implementation of xFetch and xUnfetch */
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64 iOff, int iAmt, void **pp){
+  DO_OS_MALLOC_TEST(id);
+  return id->pMethods->xFetch(id, iOff, iAmt, pp);
+}
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *id, i64 iOff, void *p){
+  return id->pMethods->xUnfetch(id, iOff, p);
+}
+#else
+/* No-op stubs to use when memory-mapped I/O is disabled */
+SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64 iOff, int iAmt, void **pp){
+  *pp = 0;
+  return SQLITE_OK;
+}
+SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *id, i64 iOff, void *p){
+  return SQLITE_OK;
+}
+#endif
+
 /*
 ** The next group of routines are convenience wrappers around the
 ** VFS methods.
@@ -15506,14 +15848,14 @@ static int sqlite3MemInit(void *NotUsed){
   }else{
     /* only 1 core, use our own zone to contention over global locks, 
     ** e.g. we have our own dedicated locks */
-    bool success;		
+    bool success;
     malloc_zone_t* newzone = malloc_create_zone(4096, 0);
     malloc_set_zone_name(newzone, "Sqlite_Heap");
     do{
       success = OSAtomicCompareAndSwapPtrBarrier(NULL, newzone, 
                                  (void * volatile *)&_sqliteZone_);
     }while(!_sqliteZone_);
-    if( !success ){	
+    if( !success ){
       /* somebody registered a zone first */
       malloc_destroy_zone(newzone);
     }
@@ -16905,13 +17247,13 @@ static SQLITE_WSD struct Mem5Global {
 } mem5;
 
 /*
-** Access the static variable through a macro for SQLITE_OMIT_WSD
+** Access the static variable through a macro for SQLITE_OMIT_WSD.
 */
 #define mem5 GLOBAL(struct Mem5Global, mem5)
 
 /*
 ** Assuming mem5.zPool is divided up into an array of Mem5Link
-** structures, return a pointer to the idx-th such lik.
+** structures, return a pointer to the idx-th such link.
 */
 #define MEM5LINK(idx) ((Mem5Link *)(&mem5.zPool[(idx)*mem5.szAtom]))
 
@@ -17007,7 +17349,7 @@ static int memsys5UnlinkFirst(int iLogsize){
 ** Return a block of memory of at least nBytes in size.
 ** Return NULL if unable.  Return NULL if nBytes==0.
 **
-** The caller guarantees that nByte positive.
+** The caller guarantees that nByte is positive.
 **
 ** The caller has obtained a mutex prior to invoking this
 ** routine so there is never any chance that two or more
@@ -17129,7 +17471,7 @@ static void memsys5FreeUnsafe(void *pOld){
 }
 
 /*
-** Allocate nBytes of memory
+** Allocate nBytes of memory.
 */
 static void *memsys5Malloc(int nBytes){
   sqlite3_int64 *p = 0;
@@ -17719,282 +18061,6 @@ SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
 #endif /* !defined(SQLITE_MUTEX_OMIT) */
 
 /************** End of mutex_noop.c ******************************************/
-/************** Begin file mutex_os2.c ***************************************/
-/*
-** 2007 August 28
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-*************************************************************************
-** This file contains the C functions that implement mutexes for OS/2
-*/
-
-/*
-** The code in this file is only used if SQLITE_MUTEX_OS2 is defined.
-** See the mutex.h file for details.
-*/
-#ifdef SQLITE_MUTEX_OS2
-
-/********************** OS/2 Mutex Implementation **********************
-**
-** This implementation of mutexes is built using the OS/2 API.
-*/
-
-/*
-** The mutex object
-** Each recursive mutex is an instance of the following structure.
-*/
-struct sqlite3_mutex {
-  HMTX mutex;       /* Mutex controlling the lock */
-  int  id;          /* Mutex type */
-#ifdef SQLITE_DEBUG
- int   trace;       /* True to trace changes */
-#endif
-};
-
-#ifdef SQLITE_DEBUG
-#define SQLITE3_MUTEX_INITIALIZER { 0, 0, 0 }
-#else
-#define SQLITE3_MUTEX_INITIALIZER { 0, 0 }
-#endif
-
-/*
-** Initialize and deinitialize the mutex subsystem.
-*/
-static int os2MutexInit(void){ return SQLITE_OK; }
-static int os2MutexEnd(void){ return SQLITE_OK; }
-
-/*
-** The sqlite3_mutex_alloc() routine allocates a new
-** mutex and returns a pointer to it.  If it returns NULL
-** that means that a mutex could not be allocated. 
-** SQLite will unwind its stack and return an error.  The argument
-** to sqlite3_mutex_alloc() is one of these integer constants:
-**
-** <ul>
-** <li>  SQLITE_MUTEX_FAST
-** <li>  SQLITE_MUTEX_RECURSIVE
-** <li>  SQLITE_MUTEX_STATIC_MASTER
-** <li>  SQLITE_MUTEX_STATIC_MEM
-** <li>  SQLITE_MUTEX_STATIC_MEM2
-** <li>  SQLITE_MUTEX_STATIC_PRNG
-** <li>  SQLITE_MUTEX_STATIC_LRU
-** <li>  SQLITE_MUTEX_STATIC_LRU2
-** </ul>
-**
-** The first two constants cause sqlite3_mutex_alloc() to create
-** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
-** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
-** The mutex implementation does not need to make a distinction
-** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
-** not want to.  But SQLite will only request a recursive mutex in
-** cases where it really needs one.  If a faster non-recursive mutex
-** implementation is available on the host platform, the mutex subsystem
-** might return such a mutex in response to SQLITE_MUTEX_FAST.
-**
-** The other allowed parameters to sqlite3_mutex_alloc() each return
-** a pointer to a static preexisting mutex.  Six static mutexes are
-** used by the current version of SQLite.  Future versions of SQLite
-** may add additional static mutexes.  Static mutexes are for internal
-** use by SQLite only.  Applications that use SQLite mutexes should
-** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
-** SQLITE_MUTEX_RECURSIVE.
-**
-** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
-** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
-** returns a different mutex on every call.  But for the static
-** mutex types, the same mutex is returned on every call that has
-** the same type number.
-*/
-static sqlite3_mutex *os2MutexAlloc(int iType){
-  sqlite3_mutex *p = NULL;
-  switch( iType ){
-    case SQLITE_MUTEX_FAST:
-    case SQLITE_MUTEX_RECURSIVE: {
-      p = sqlite3MallocZero( sizeof(*p) );
-      if( p ){
-        p->id = iType;
-        if( DosCreateMutexSem( 0, &p->mutex, 0, FALSE ) != NO_ERROR ){
-          sqlite3_free( p );
-          p = NULL;
-        }
-      }
-      break;
-    }
-    default: {
-      static volatile int isInit = 0;
-      static sqlite3_mutex staticMutexes[6] = {
-        SQLITE3_MUTEX_INITIALIZER,
-        SQLITE3_MUTEX_INITIALIZER,
-        SQLITE3_MUTEX_INITIALIZER,
-        SQLITE3_MUTEX_INITIALIZER,
-        SQLITE3_MUTEX_INITIALIZER,
-        SQLITE3_MUTEX_INITIALIZER,
-      };
-      if ( !isInit ){
-        APIRET rc;
-        PTIB ptib;
-        PPIB ppib;
-        HMTX mutex;
-        char name[32];
-        DosGetInfoBlocks( &ptib, &ppib );
-        sqlite3_snprintf( sizeof(name), name, "\\SEM32\\SQLITE%04x",
-                          ppib->pib_ulpid );
-        while( !isInit ){
-          mutex = 0;
-          rc = DosCreateMutexSem( name, &mutex, 0, FALSE);
-          if( rc == NO_ERROR ){
-            unsigned int i;
-            if( !isInit ){
-              for( i = 0; i < sizeof(staticMutexes)/sizeof(staticMutexes[0]); i++ ){
-                DosCreateMutexSem( 0, &staticMutexes[i].mutex, 0, FALSE );
-              }
-              isInit = 1;
-            }
-            DosCloseMutexSem( mutex );
-          }else if( rc == ERROR_DUPLICATE_NAME ){
-            DosSleep( 1 );
-          }else{
-            return p;
-          }
-        }
-      }
-      assert( iType-2 >= 0 );
-      assert( iType-2 < sizeof(staticMutexes)/sizeof(staticMutexes[0]) );
-      p = &staticMutexes[iType-2];
-      p->id = iType;
-      break;
-    }
-  }
-  return p;
-}
-
-
-/*
-** This routine deallocates a previously allocated mutex.
-** SQLite is careful to deallocate every mutex that it allocates.
-*/
-static void os2MutexFree(sqlite3_mutex *p){
-#ifdef SQLITE_DEBUG
-  TID tid;
-  PID pid;
-  ULONG ulCount;
-  DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
-  assert( ulCount==0 );
-  assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
-#endif
-  DosCloseMutexSem( p->mutex );
-  sqlite3_free( p );
-}
-
-#ifdef SQLITE_DEBUG
-/*
-** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
-** intended for use inside assert() statements.
-*/
-static int os2MutexHeld(sqlite3_mutex *p){
-  TID tid;
-  PID pid;
-  ULONG ulCount;
-  PTIB ptib;
-  DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
-  if( ulCount==0 || ( ulCount>1 && p->id!=SQLITE_MUTEX_RECURSIVE ) )
-    return 0;
-  DosGetInfoBlocks(&ptib, NULL);
-  return tid==ptib->tib_ptib2->tib2_ultid;
-}
-static int os2MutexNotheld(sqlite3_mutex *p){
-  TID tid;
-  PID pid;
-  ULONG ulCount;
-  PTIB ptib;
-  DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
-  if( ulCount==0 )
-    return 1;
-  DosGetInfoBlocks(&ptib, NULL);
-  return tid!=ptib->tib_ptib2->tib2_ultid;
-}
-static void os2MutexTrace(sqlite3_mutex *p, char *pAction){
-  TID   tid;
-  PID   pid;
-  ULONG ulCount;
-  DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
-  printf("%s mutex %p (%d) with nRef=%ld\n", pAction, (void*)p, p->trace, ulCount);
-}
-#endif
-
-/*
-** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
-** to enter a mutex.  If another thread is already within the mutex,
-** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
-** SQLITE_BUSY.  The sqlite3_mutex_try() interface returns SQLITE_OK
-** upon successful entry.  Mutexes created using SQLITE_MUTEX_RECURSIVE can
-** be entered multiple times by the same thread.  In such cases the,
-** mutex must be exited an equal number of times before another thread
-** can enter.  If the same thread tries to enter any other kind of mutex
-** more than once, the behavior is undefined.
-*/
-static void os2MutexEnter(sqlite3_mutex *p){
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || os2MutexNotheld(p) );
-  DosRequestMutexSem(p->mutex, SEM_INDEFINITE_WAIT);
-#ifdef SQLITE_DEBUG
-  if( p->trace ) os2MutexTrace(p, "enter");
-#endif
-}
-static int os2MutexTry(sqlite3_mutex *p){
-  int rc = SQLITE_BUSY;
-  assert( p->id==SQLITE_MUTEX_RECURSIVE || os2MutexNotheld(p) );
-  if( DosRequestMutexSem(p->mutex, SEM_IMMEDIATE_RETURN) == NO_ERROR ) {
-    rc = SQLITE_OK;
-#ifdef SQLITE_DEBUG
-    if( p->trace ) os2MutexTrace(p, "try");
-#endif
-  }
-  return rc;
-}
-
-/*
-** The sqlite3_mutex_leave() routine exits a mutex that was
-** previously entered by the same thread.  The behavior
-** is undefined if the mutex is not currently entered or
-** is not currently allocated.  SQLite will never do either.
-*/
-static void os2MutexLeave(sqlite3_mutex *p){
-  assert( os2MutexHeld(p) );
-  DosReleaseMutexSem(p->mutex);
-#ifdef SQLITE_DEBUG
-  if( p->trace ) os2MutexTrace(p, "leave");
-#endif
-}
-
-SQLITE_PRIVATE sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
-  static const sqlite3_mutex_methods sMutex = {
-    os2MutexInit,
-    os2MutexEnd,
-    os2MutexAlloc,
-    os2MutexFree,
-    os2MutexEnter,
-    os2MutexTry,
-    os2MutexLeave,
-#ifdef SQLITE_DEBUG
-    os2MutexHeld,
-    os2MutexNotheld
-#else
-    0,
-    0
-#endif
-  };
-
-  return &sMutex;
-}
-#endif /* SQLITE_MUTEX_OS2 */
-
-/************** End of mutex_os2.c *******************************************/
 /************** Begin file mutex_unix.c **************************************/
 /*
 ** 2007 August 28
@@ -18459,7 +18525,7 @@ static int winMutex_isInit = 0;
 */
 static long winMutex_lock = 0;
 
-SQLITE_API extern void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */
+SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */
 
 static int winMutexInit(void){ 
   /* The first to increment to 1 does actual initialization */
@@ -19602,7 +19668,8 @@ static const et_info fmtinfo[] = {
 static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
   int digit;
   LONGDOUBLE_TYPE d;
-  if( (*cnt)++ >= 16 ) return '0';
+  if( (*cnt)<=0 ) return '0';
+  (*cnt)--;
   digit = (int)*val;
   d = digit;
   digit += '0';
@@ -19836,7 +19903,7 @@ SQLITE_PRIVATE void sqlite3VXPrintf(
           nOut = precision + 10;
           zOut = zExtra = sqlite3Malloc( nOut );
           if( zOut==0 ){
-            pAccum->mallocFailed = 1;
+            pAccum->accError = STRACCUM_NOMEM;
             return;
           }
         }
@@ -19890,13 +19957,7 @@ SQLITE_PRIVATE void sqlite3VXPrintf(
           else                         prefix = 0;
         }
         if( xtype==etGENERIC && precision>0 ) precision--;
-#if 0
-        /* Rounding works like BSD when the constant 0.4999 is used.  Wierd! */
-        for(idx=precision, rounder=0.4999; idx>0; idx--, rounder*=0.1);
-#else
-        /* It makes more sense to use 0.5 */
         for(idx=precision, rounder=0.5; idx>0; idx--, rounder*=0.1){}
-#endif
         if( xtype==etFLOAT ) realvalue += rounder;
         /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
         exp = 0;
@@ -19906,9 +19967,12 @@ SQLITE_PRIVATE void sqlite3VXPrintf(
           break;
         }
         if( realvalue>0.0 ){
-          while( realvalue>=1e32 && exp<=350 ){ realvalue *= 1e-32; exp+=32; }
-          while( realvalue>=1e8 && exp<=350 ){ realvalue *= 1e-8; exp+=8; }
-          while( realvalue>=10.0 && exp<=350 ){ realvalue *= 0.1; exp++; }
+          LONGDOUBLE_TYPE scale = 1.0;
+          while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
+          while( realvalue>=1e64*scale && exp<=350 ){ scale *= 1e64; exp+=64; }
+          while( realvalue>=1e8*scale && exp<=350 ){ scale *= 1e8; exp+=8; }
+          while( realvalue>=10.0*scale && exp<=350 ){ scale *= 10.0; exp++; }
+          realvalue /= scale;
           while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
           while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
           if( exp>350 ){
@@ -19941,22 +20005,22 @@ SQLITE_PRIVATE void sqlite3VXPrintf(
             xtype = etFLOAT;
           }
         }else{
-          flag_rtz = 0;
+          flag_rtz = flag_altform2;
         }
         if( xtype==etEXP ){
           e2 = 0;
         }else{
           e2 = exp;
         }
-        if( e2+precision+width > etBUFSIZE - 15 ){
-          bufpt = zExtra = sqlite3Malloc( e2+precision+width+15 );
+        if( MAX(e2,0)+precision+width > etBUFSIZE - 15 ){
+          bufpt = zExtra = sqlite3Malloc( MAX(e2,0)+precision+width+15 );
           if( bufpt==0 ){
-            pAccum->mallocFailed = 1;
+            pAccum->accError = STRACCUM_NOMEM;
             return;
           }
         }
         zOut = bufpt;
-        nsd = 0;
+        nsd = 16 + flag_altform2*10;
         flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
         /* The sign in front of the number */
         if( prefix ){
@@ -20086,7 +20150,7 @@ SQLITE_PRIVATE void sqlite3VXPrintf(
         if( n>etBUFSIZE ){
           bufpt = zExtra = sqlite3Malloc( n );
           if( bufpt==0 ){
-            pAccum->mallocFailed = 1;
+            pAccum->accError = STRACCUM_NOMEM;
             return;
           }
         }else{
@@ -20164,22 +20228,20 @@ SQLITE_PRIVATE void sqlite3VXPrintf(
 */
 SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
   assert( z!=0 || N==0 );
-  if( p->tooBig | p->mallocFailed ){
-    testcase(p->tooBig);
-    testcase(p->mallocFailed);
+  if( p->accError ){
+    testcase(p->accError==STRACCUM_TOOBIG);
+    testcase(p->accError==STRACCUM_NOMEM);
     return;
   }
   assert( p->zText!=0 || p->nChar==0 );
-  if( N<0 ){
+  if( N<=0 ){
+    if( N==0 || z[0]==0 ) return;
     N = sqlite3Strlen30(z);
   }
-  if( N==0 || NEVER(z==0) ){
-    return;
-  }
   if( p->nChar+N >= p->nAlloc ){
     char *zNew;
     if( !p->useMalloc ){
-      p->tooBig = 1;
+      p->accError = STRACCUM_TOOBIG;
       N = p->nAlloc - p->nChar - 1;
       if( N<=0 ){
         return;
@@ -20190,7 +20252,7 @@ SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
       szNew += N + 1;
       if( szNew > p->mxAlloc ){
         sqlite3StrAccumReset(p);
-        p->tooBig = 1;
+        p->accError = STRACCUM_TOOBIG;
         return;
       }else{
         p->nAlloc = (int)szNew;
@@ -20204,7 +20266,7 @@ SQLITE_PRIVATE void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
         if( zOld==0 && p->nChar>0 ) memcpy(zNew, p->zText, p->nChar);
         p->zText = zNew;
       }else{
-        p->mallocFailed = 1;
+        p->accError = STRACCUM_NOMEM;
         sqlite3StrAccumReset(p);
         return;
       }
@@ -20232,7 +20294,7 @@ SQLITE_PRIVATE char *sqlite3StrAccumFinish(StrAccum *p){
       if( p->zText ){
         memcpy(p->zText, p->zBase, p->nChar+1);
       }else{
-        p->mallocFailed = 1;
+        p->accError = STRACCUM_NOMEM;
       }
     }
   }
@@ -20263,8 +20325,7 @@ SQLITE_PRIVATE void sqlite3StrAccumInit(StrAccum *p, char *zBase, int n, int mx)
   p->nAlloc = n;
   p->mxAlloc = mx;
   p->useMalloc = 1;
-  p->tooBig = 0;
-  p->mallocFailed = 0;
+  p->accError = 0;
 }
 
 /*
@@ -20281,7 +20342,7 @@ SQLITE_PRIVATE char *sqlite3VMPrintf(sqlite3 *db, const char *zFormat, va_list a
   acc.db = db;
   sqlite3VXPrintf(&acc, 1, zFormat, ap);
   z = sqlite3StrAccumFinish(&acc);
-  if( acc.mallocFailed ){
+  if( acc.accError==STRACCUM_NOMEM ){
     db->mallocFailed = 1;
   }
   return z;
@@ -20478,24 +20539,11 @@ static SQLITE_WSD struct sqlite3PrngType {
 } sqlite3Prng;
 
 /*
-** Get a single 8-bit random value from the RC4 PRNG.  The Mutex
-** must be held while executing this routine.
-**
-** Why not just use a library random generator like lrand48() for this?
-** Because the OP_NewRowid opcode in the VDBE depends on having a very
-** good source of random numbers.  The lrand48() library function may
-** well be good enough.  But maybe not.  Or maybe lrand48() has some
-** subtle problems on some systems that could cause problems.  It is hard
-** to know.  To minimize the risk of problems due to bad lrand48()
-** implementations, SQLite uses this random number generator based
-** on RC4, which we know works very well.
-**
-** (Later):  Actually, OP_NewRowid does not depend on a good source of
-** randomness any more.  But we will leave this code in all the same.
+** Return N random bytes.
 */
-static u8 randomByte(void){
+SQLITE_API void sqlite3_randomness(int N, void *pBuf){
   unsigned char t;
-
+  unsigned char *zBuf = pBuf;
 
   /* The "wsdPrng" macro will resolve to the pseudo-random number generator
   ** state vector.  If writable static data is unsupported on the target,
@@ -20510,6 +20558,10 @@ static u8 randomByte(void){
 # define wsdPrng sqlite3Prng
 #endif
 
+#if SQLITE_THREADSAFE
+  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
+  sqlite3_mutex_enter(mutex);
+#endif
 
   /* Initialize the state of the random number generator once,
   ** the first time this routine is called.  The seed value does
@@ -20538,28 +20590,14 @@ static u8 randomByte(void){
     wsdPrng.isInit = 1;
   }
 
-  /* Generate and return single random byte
-  */
-  wsdPrng.i++;
-  t = wsdPrng.s[wsdPrng.i];
-  wsdPrng.j += t;
-  wsdPrng.s[wsdPrng.i] = wsdPrng.s[wsdPrng.j];
-  wsdPrng.s[wsdPrng.j] = t;
-  t += wsdPrng.s[wsdPrng.i];
-  return wsdPrng.s[t];
-}
-
-/*
-** Return N random bytes.
-*/
-SQLITE_API void sqlite3_randomness(int N, void *pBuf){
-  unsigned char *zBuf = pBuf;
-#if SQLITE_THREADSAFE
-  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
-#endif
-  sqlite3_mutex_enter(mutex);
   while( N-- ){
-    *(zBuf++) = randomByte();
+    wsdPrng.i++;
+    t = wsdPrng.s[wsdPrng.i];
+    wsdPrng.j += t;
+    wsdPrng.s[wsdPrng.i] = wsdPrng.s[wsdPrng.j];
+    wsdPrng.s[wsdPrng.j] = t;
+    t += wsdPrng.s[wsdPrng.i];
+    *(zBuf++) = wsdPrng.s[t];
   }
   sqlite3_mutex_leave(mutex);
 }
@@ -20760,25 +20798,23 @@ static const unsigned char sqlite3Utf8Trans1[] = {
         || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }        \
   }
 SQLITE_PRIVATE u32 sqlite3Utf8Read(
-  const unsigned char *zIn,       /* First byte of UTF-8 character */
-  const unsigned char **pzNext    /* Write first byte past UTF-8 char here */
+  const unsigned char **pz    /* Pointer to string from which to read char */
 ){
   unsigned int c;
 
   /* Same as READ_UTF8() above but without the zTerm parameter.
   ** For this routine, we assume the UTF8 string is always zero-terminated.
   */
-  c = *(zIn++);
+  c = *((*pz)++);
   if( c>=0xc0 ){
     c = sqlite3Utf8Trans1[c-0xc0];
-    while( (*zIn & 0xc0)==0x80 ){
-      c = (c<<6) + (0x3f & *(zIn++));
+    while( (*(*pz) & 0xc0)==0x80 ){
+      c = (c<<6) + (0x3f & *((*pz)++));
     }
     if( c<0x80
         || (c&0xFFFFF800)==0xD800
         || (c&0xFFFFFFFE)==0xFFFE ){  c = 0xFFFD; }
   }
-  *pzNext = zIn;
   return c;
 }
 
@@ -20879,7 +20915,6 @@ SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
     if( desiredEnc==SQLITE_UTF16LE ){
       /* UTF-8 -> UTF-16 Little-endian */
       while( zIn<zTerm ){
-        /* c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn); */
         READ_UTF8(zIn, zTerm, c);
         WRITE_UTF16LE(z, c);
       }
@@ -20887,7 +20922,6 @@ SQLITE_PRIVATE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
       assert( desiredEnc==SQLITE_UTF16BE );
       /* UTF-8 -> UTF-16 Big-endian */
       while( zIn<zTerm ){
-        /* c = sqlite3Utf8Read(zIn, zTerm, (const u8**)&zIn); */
         READ_UTF8(zIn, zTerm, c);
         WRITE_UTF16BE(z, c);
       }
@@ -21015,7 +21049,7 @@ SQLITE_PRIVATE int sqlite3Utf8To8(unsigned char *zIn){
   u32 c;
 
   while( zIn[0] && zOut<=zIn ){
-    c = sqlite3Utf8Read(zIn, (const u8**)&zIn);
+    c = sqlite3Utf8Read((const u8**)&zIn);
     if( c!=0xfffd ){
       WRITE_UTF8(zOut, c);
     }
@@ -21120,7 +21154,7 @@ SQLITE_PRIVATE void sqlite3UtfSelfTest(void){
     assert( n>0 && n<=4 );
     z[0] = 0;
     z = zBuf;
-    c = sqlite3Utf8Read(z, (const u8**)&z);
+    c = sqlite3Utf8Read((const u8**)&z);
     t = i;
     if( i>=0xD800 && i<=0xDFFF ) t = 0xFFFD;
     if( (i&0xFFFFFFFE)==0xFFFE ) t = 0xFFFD;
@@ -21419,7 +21453,7 @@ SQLITE_API int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
 */
 SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult, int length, u8 enc){
 #ifndef SQLITE_OMIT_FLOATING_POINT
-  int incr = (enc==SQLITE_UTF8?1:2);
+  int incr;
   const char *zEnd = z + length;
   /* sign * significand * (10 ^ (esign * exponent)) */
   int sign = 1;    /* sign of significand */
@@ -21430,10 +21464,22 @@ SQLITE_PRIVATE int sqlite3AtoF(const char *z, double *pResult, int length, u8 en
   int eValid = 1;  /* True exponent is either not used or is well-formed */
   double result;
   int nDigits = 0;
+  int nonNum = 0;
 
+  assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
   *pResult = 0.0;   /* Default return value, in case of an error */
 
-  if( enc==SQLITE_UTF16BE ) z++;
+  if( enc==SQLITE_UTF8 ){
+    incr = 1;
+  }else{
+    int i;
+    incr = 2;
+    assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+    for(i=3-enc; i<length && z[i]==0; i+=2){}
+    nonNum = i<length;
+    zEnd = z+i+enc-3;
+    z += (enc&1);
+  }
 
   /* skip leading spaces */
   while( z<zEnd && sqlite3Isspace(*z) ) z+=incr;
@@ -21529,7 +21575,7 @@ do_atof_calc:
     /* if exponent, scale significand as appropriate
     ** and store in result. */
     if( e ){
-      double scale = 1.0;
+      LONGDOUBLE_TYPE scale = 1.0;
       /* attempt to handle extremely small/large numbers better */
       if( e>307 && e<342 ){
         while( e%308 ) { scale *= 1.0e+1; e -= 1; }
@@ -21566,7 +21612,7 @@ do_atof_calc:
   *pResult = result;
 
   /* return true if number and no extra non-whitespace chracters after */
-  return z>=zEnd && nDigits>0 && eValid;
+  return z>=zEnd && nDigits>0 && eValid && nonNum==0;
 #else
   return !sqlite3Atoi64(z, pResult, length, enc);
 #endif /* SQLITE_OMIT_FLOATING_POINT */
@@ -21615,21 +21661,33 @@ static int compare2pow63(const char *zNum, int incr){
 ** signed 64-bit integer, its negative -9223372036854665808 can be.
 **
 ** If zNum is too big for a 64-bit integer and is not
-** 9223372036854665808 then return 1.
+** 9223372036854665808  or if zNum contains any non-numeric text,
+** then return 1.
 **
 ** length is the number of bytes in the string (bytes, not characters).
 ** The string is not necessarily zero-terminated.  The encoding is
 ** given by enc.
 */
 SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc){
-  int incr = (enc==SQLITE_UTF8?1:2);
+  int incr;
   u64 u = 0;
   int neg = 0; /* assume positive */
   int i;
   int c = 0;
+  int nonNum = 0;
   const char *zStart;
   const char *zEnd = zNum + length;
-  if( enc==SQLITE_UTF16BE ) zNum++;
+  assert( enc==SQLITE_UTF8 || enc==SQLITE_UTF16LE || enc==SQLITE_UTF16BE );
+  if( enc==SQLITE_UTF8 ){
+    incr = 1;
+  }else{
+    incr = 2;
+    assert( SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
+    for(i=3-enc; i<length && zNum[i]==0; i+=2){}
+    nonNum = i<length;
+    zEnd = zNum+i+enc-3;
+    zNum += (enc&1);
+  }
   while( zNum<zEnd && sqlite3Isspace(*zNum) ) zNum+=incr;
   if( zNum<zEnd ){
     if( *zNum=='-' ){
@@ -21654,7 +21712,7 @@ SQLITE_PRIVATE int sqlite3Atoi64(const char *zNum, i64 *pNum, int length, u8 enc
   testcase( i==18 );
   testcase( i==19 );
   testcase( i==20 );
-  if( (c!=0 && &zNum[i]<zEnd) || (i==0 && zStart==zNum) || i>19*incr ){
+  if( (c!=0 && &zNum[i]<zEnd) || (i==0 && zStart==zNum) || i>19*incr || nonNum ){
     /* zNum is empty or contains non-numeric text or is longer
     ** than 19 digits (thus guaranteeing that it is too large) */
     return 1;
@@ -22458,7 +22516,11 @@ static int rehash(Hash *pH, unsigned int new_size){
 
   /* The inability to allocates space for a larger hash table is
   ** a performance hit but it is not a fatal error.  So mark the
-  ** allocation as a benign.
+  ** allocation as a benign. Use sqlite3Malloc()/memset(0) instead of 
+  ** sqlite3MallocZero() to make the allocation, as sqlite3MallocZero()
+  ** only zeroes the requested number of bytes whereas this module will
+  ** use the actual amount of space allocated for the hash table (which
+  ** may be larger than the requested amount).
   */
   sqlite3BeginBenignMalloc();
   new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
@@ -22534,7 +22596,7 @@ static void removeElementGivenHash(
   }
   sqlite3_free( elem );
   pH->count--;
-  if( pH->count<=0 ){
+  if( pH->count==0 ){
     assert( pH->first==0 );
     assert( pH->count==0 );
     sqlite3HashClear(pH);
@@ -22628,78 +22690,78 @@ SQLITE_PRIVATE void *sqlite3HashInsert(Hash *pH, const char *pKey, int nKey, voi
 #if !defined(SQLITE_OMIT_EXPLAIN) || !defined(NDEBUG) || defined(VDBE_PROFILE) || defined(SQLITE_DEBUG)
 SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
  static const char *const azName[] = { "?",
-     /*   1 */ "Goto",
-     /*   2 */ "Gosub",
-     /*   3 */ "Return",
-     /*   4 */ "Yield",
-     /*   5 */ "HaltIfNull",
-     /*   6 */ "Halt",
-     /*   7 */ "Integer",
-     /*   8 */ "Int64",
-     /*   9 */ "String",
-     /*  10 */ "Null",
-     /*  11 */ "Blob",
-     /*  12 */ "Variable",
-     /*  13 */ "Move",
-     /*  14 */ "Copy",
-     /*  15 */ "SCopy",
-     /*  16 */ "ResultRow",
-     /*  17 */ "CollSeq",
-     /*  18 */ "Function",
+     /*   1 */ "Function",
+     /*   2 */ "Savepoint",
+     /*   3 */ "AutoCommit",
+     /*   4 */ "Transaction",
+     /*   5 */ "SorterNext",
+     /*   6 */ "Prev",
+     /*   7 */ "Next",
+     /*   8 */ "AggStep",
+     /*   9 */ "Checkpoint",
+     /*  10 */ "JournalMode",
+     /*  11 */ "Vacuum",
+     /*  12 */ "VFilter",
+     /*  13 */ "VUpdate",
+     /*  14 */ "Goto",
+     /*  15 */ "Gosub",
+     /*  16 */ "Return",
+     /*  17 */ "Yield",
+     /*  18 */ "HaltIfNull",
      /*  19 */ "Not",
-     /*  20 */ "AddImm",
-     /*  21 */ "MustBeInt",
-     /*  22 */ "RealAffinity",
-     /*  23 */ "Permutation",
-     /*  24 */ "Compare",
-     /*  25 */ "Jump",
-     /*  26 */ "Once",
-     /*  27 */ "If",
-     /*  28 */ "IfNot",
-     /*  29 */ "Column",
-     /*  30 */ "Affinity",
-     /*  31 */ "MakeRecord",
-     /*  32 */ "Count",
-     /*  33 */ "Savepoint",
-     /*  34 */ "AutoCommit",
-     /*  35 */ "Transaction",
-     /*  36 */ "ReadCookie",
-     /*  37 */ "SetCookie",
-     /*  38 */ "VerifyCookie",
-     /*  39 */ "OpenRead",
-     /*  40 */ "OpenWrite",
-     /*  41 */ "OpenAutoindex",
-     /*  42 */ "OpenEphemeral",
-     /*  43 */ "SorterOpen",
-     /*  44 */ "OpenPseudo",
-     /*  45 */ "Close",
-     /*  46 */ "SeekLt",
-     /*  47 */ "SeekLe",
-     /*  48 */ "SeekGe",
-     /*  49 */ "SeekGt",
-     /*  50 */ "Seek",
-     /*  51 */ "NotFound",
-     /*  52 */ "Found",
-     /*  53 */ "IsUnique",
-     /*  54 */ "NotExists",
-     /*  55 */ "Sequence",
-     /*  56 */ "NewRowid",
-     /*  57 */ "Insert",
-     /*  58 */ "InsertInt",
-     /*  59 */ "Delete",
-     /*  60 */ "ResetCount",
-     /*  61 */ "SorterCompare",
-     /*  62 */ "SorterData",
-     /*  63 */ "RowKey",
-     /*  64 */ "RowData",
-     /*  65 */ "Rowid",
-     /*  66 */ "NullRow",
-     /*  67 */ "Last",
+     /*  20 */ "Halt",
+     /*  21 */ "Integer",
+     /*  22 */ "Int64",
+     /*  23 */ "String",
+     /*  24 */ "Null",
+     /*  25 */ "Blob",
+     /*  26 */ "Variable",
+     /*  27 */ "Move",
+     /*  28 */ "Copy",
+     /*  29 */ "SCopy",
+     /*  30 */ "ResultRow",
+     /*  31 */ "CollSeq",
+     /*  32 */ "AddImm",
+     /*  33 */ "MustBeInt",
+     /*  34 */ "RealAffinity",
+     /*  35 */ "Permutation",
+     /*  36 */ "Compare",
+     /*  37 */ "Jump",
+     /*  38 */ "Once",
+     /*  39 */ "If",
+     /*  40 */ "IfNot",
+     /*  41 */ "Column",
+     /*  42 */ "Affinity",
+     /*  43 */ "MakeRecord",
+     /*  44 */ "Count",
+     /*  45 */ "ReadCookie",
+     /*  46 */ "SetCookie",
+     /*  47 */ "VerifyCookie",
+     /*  48 */ "OpenRead",
+     /*  49 */ "OpenWrite",
+     /*  50 */ "OpenAutoindex",
+     /*  51 */ "OpenEphemeral",
+     /*  52 */ "SorterOpen",
+     /*  53 */ "OpenPseudo",
+     /*  54 */ "Close",
+     /*  55 */ "SeekLt",
+     /*  56 */ "SeekLe",
+     /*  57 */ "SeekGe",
+     /*  58 */ "SeekGt",
+     /*  59 */ "Seek",
+     /*  60 */ "NotFound",
+     /*  61 */ "Found",
+     /*  62 */ "IsUnique",
+     /*  63 */ "NotExists",
+     /*  64 */ "Sequence",
+     /*  65 */ "NewRowid",
+     /*  66 */ "Insert",
+     /*  67 */ "InsertInt",
      /*  68 */ "Or",
      /*  69 */ "And",
-     /*  70 */ "SorterSort",
-     /*  71 */ "Sort",
-     /*  72 */ "Rewind",
+     /*  70 */ "Delete",
+     /*  71 */ "ResetCount",
+     /*  72 */ "SorterCompare",
      /*  73 */ "IsNull",
      /*  74 */ "NotNull",
      /*  75 */ "Ne",
@@ -22708,7 +22770,7 @@ SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
      /*  78 */ "Le",
      /*  79 */ "Lt",
      /*  80 */ "Ge",
-     /*  81 */ "SorterNext",
+     /*  81 */ "SorterData",
      /*  82 */ "BitAnd",
      /*  83 */ "BitOr",
      /*  84 */ "ShiftLeft",
@@ -22719,55 +22781,55 @@ SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
      /*  89 */ "Divide",
      /*  90 */ "Remainder",
      /*  91 */ "Concat",
-     /*  92 */ "Prev",
+     /*  92 */ "RowKey",
      /*  93 */ "BitNot",
      /*  94 */ "String8",
-     /*  95 */ "Next",
-     /*  96 */ "SorterInsert",
-     /*  97 */ "IdxInsert",
-     /*  98 */ "IdxDelete",
-     /*  99 */ "IdxRowid",
-     /* 100 */ "IdxLT",
-     /* 101 */ "IdxGE",
-     /* 102 */ "Destroy",
-     /* 103 */ "Clear",
-     /* 104 */ "CreateIndex",
-     /* 105 */ "CreateTable",
-     /* 106 */ "ParseSchema",
-     /* 107 */ "LoadAnalysis",
-     /* 108 */ "DropTable",
-     /* 109 */ "DropIndex",
-     /* 110 */ "DropTrigger",
-     /* 111 */ "IntegrityCk",
-     /* 112 */ "RowSetAdd",
-     /* 113 */ "RowSetRead",
-     /* 114 */ "RowSetTest",
-     /* 115 */ "Program",
-     /* 116 */ "Param",
-     /* 117 */ "FkCounter",
-     /* 118 */ "FkIfZero",
-     /* 119 */ "MemMax",
-     /* 120 */ "IfPos",
-     /* 121 */ "IfNeg",
-     /* 122 */ "IfZero",
-     /* 123 */ "AggStep",
-     /* 124 */ "AggFinal",
-     /* 125 */ "Checkpoint",
-     /* 126 */ "JournalMode",
-     /* 127 */ "Vacuum",
-     /* 128 */ "IncrVacuum",
-     /* 129 */ "Expire",
+     /*  95 */ "RowData",
+     /*  96 */ "Rowid",
+     /*  97 */ "NullRow",
+     /*  98 */ "Last",
+     /*  99 */ "SorterSort",
+     /* 100 */ "Sort",
+     /* 101 */ "Rewind",
+     /* 102 */ "SorterInsert",
+     /* 103 */ "IdxInsert",
+     /* 104 */ "IdxDelete",
+     /* 105 */ "IdxRowid",
+     /* 106 */ "IdxLT",
+     /* 107 */ "IdxGE",
+     /* 108 */ "Destroy",
+     /* 109 */ "Clear",
+     /* 110 */ "CreateIndex",
+     /* 111 */ "CreateTable",
+     /* 112 */ "ParseSchema",
+     /* 113 */ "LoadAnalysis",
+     /* 114 */ "DropTable",
+     /* 115 */ "DropIndex",
+     /* 116 */ "DropTrigger",
+     /* 117 */ "IntegrityCk",
+     /* 118 */ "RowSetAdd",
+     /* 119 */ "RowSetRead",
+     /* 120 */ "RowSetTest",
+     /* 121 */ "Program",
+     /* 122 */ "Param",
+     /* 123 */ "FkCounter",
+     /* 124 */ "FkIfZero",
+     /* 125 */ "MemMax",
+     /* 126 */ "IfPos",
+     /* 127 */ "IfNeg",
+     /* 128 */ "IfZero",
+     /* 129 */ "AggFinal",
      /* 130 */ "Real",
-     /* 131 */ "TableLock",
-     /* 132 */ "VBegin",
-     /* 133 */ "VCreate",
-     /* 134 */ "VDestroy",
-     /* 135 */ "VOpen",
-     /* 136 */ "VFilter",
-     /* 137 */ "VColumn",
-     /* 138 */ "VNext",
-     /* 139 */ "VRename",
-     /* 140 */ "VUpdate",
+     /* 131 */ "IncrVacuum",
+     /* 132 */ "Expire",
+     /* 133 */ "TableLock",
+     /* 134 */ "VBegin",
+     /* 135 */ "VCreate",
+     /* 136 */ "VDestroy",
+     /* 137 */ "VOpen",
+     /* 138 */ "VColumn",
+     /* 139 */ "VNext",
+     /* 140 */ "VRename",
      /* 141 */ "ToText",
      /* 142 */ "ToBlob",
      /* 143 */ "ToNumeric",
@@ -22784,2140 +22846,6 @@ SQLITE_PRIVATE const char *sqlite3OpcodeName(int i){
 #endif
 
 /************** End of opcodes.c *********************************************/
-/************** Begin file os_os2.c ******************************************/
-/*
-** 2006 Feb 14
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains code that is specific to OS/2.
-*/
-
-
-#if SQLITE_OS_OS2
-
-/*
-** A Note About Memory Allocation:
-**
-** This driver uses malloc()/free() directly rather than going through
-** the SQLite-wrappers sqlite3_malloc()/sqlite3_free().  Those wrappers
-** are designed for use on embedded systems where memory is scarce and
-** malloc failures happen frequently.  OS/2 does not typically run on
-** embedded systems, and when it does the developers normally have bigger
-** problems to worry about than running out of memory.  So there is not
-** a compelling need to use the wrappers.
-**
-** But there is a good reason to not use the wrappers.  If we use the
-** wrappers then we will get simulated malloc() failures within this
-** driver.  And that causes all kinds of problems for our tests.  We
-** could enhance SQLite to deal with simulated malloc failures within
-** the OS driver, but the code to deal with those failure would not
-** be exercised on Linux (which does not need to malloc() in the driver)
-** and so we would have difficulty writing coverage tests for that
-** code.  Better to leave the code out, we think.
-**
-** The point of this discussion is as follows:  When creating a new
-** OS layer for an embedded system, if you use this file as an example,
-** avoid the use of malloc()/free().  Those routines work ok on OS/2
-** desktops but not so well in embedded systems.
-*/
-
-/*
-** Macros used to determine whether or not to use threads.
-*/
-#if defined(SQLITE_THREADSAFE) && SQLITE_THREADSAFE
-# define SQLITE_OS2_THREADS 1
-#endif
-
-/*
-** Include code that is common to all os_*.c files
-*/
-/************** Include os_common.h in the middle of os_os2.c ****************/
-/************** Begin file os_common.h ***************************************/
-/*
-** 2004 May 22
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains macros and a little bit of code that is common to
-** all of the platform-specific files (os_*.c) and is #included into those
-** files.
-**
-** This file should be #included by the os_*.c files only.  It is not a
-** general purpose header file.
-*/
-#ifndef _OS_COMMON_H_
-#define _OS_COMMON_H_
-
-/*
-** At least two bugs have slipped in because we changed the MEMORY_DEBUG
-** macro to SQLITE_DEBUG and some older makefiles have not yet made the
-** switch.  The following code should catch this problem at compile-time.
-*/
-#ifdef MEMORY_DEBUG
-# error "The MEMORY_DEBUG macro is obsolete.  Use SQLITE_DEBUG instead."
-#endif
-
-#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
-# ifndef SQLITE_DEBUG_OS_TRACE
-#   define SQLITE_DEBUG_OS_TRACE 0
-# endif
-  int sqlite3OSTrace = SQLITE_DEBUG_OS_TRACE;
-# define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
-#else
-# define OSTRACE(X)
-#endif
-
-/*
-** Macros for performance tracing.  Normally turned off.  Only works
-** on i486 hardware.
-*/
-#ifdef SQLITE_PERFORMANCE_TRACE
-
-/* 
-** hwtime.h contains inline assembler code for implementing 
-** high-performance timing routines.
-*/
-/************** Include hwtime.h in the middle of os_common.h ****************/
-/************** Begin file hwtime.h ******************************************/
-/*
-** 2008 May 27
-**
-** The author disclaims copyright to this source code.  In place of
-** a legal notice, here is a blessing:
-**
-**    May you do good and not evil.
-**    May you find forgiveness for yourself and forgive others.
-**    May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file contains inline asm code for retrieving "high-performance"
-** counters for x86 class CPUs.
-*/
-#ifndef _HWTIME_H_
-#define _HWTIME_H_
-
-/*
-** The following routine only works on pentium-class (or newer) processors.
-** It uses the RDTSC opcode to read the cycle count value out of the
-** processor and returns that value.  This can be used for high-res
-** profiling.
-*/
-#if (defined(__GNUC__) || defined(_MSC_VER)) && \
-      (defined(i386) || defined(__i386__) || defined(_M_IX86))
-
-  #if defined(__GNUC__)
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-     unsigned int lo, hi;
-     __asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
-     return (sqlite_uint64)hi << 32 | lo;
-  }
-
-  #elif defined(_MSC_VER)
-
-  __declspec(naked) __inline sqlite_uint64 __cdecl sqlite3Hwtime(void){
-     __asm {
-        rdtsc
-        ret       ; return value at EDX:EAX
-     }
-  }
-
-  #endif
-
-#elif (defined(__GNUC__) && defined(__x86_64__))
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-      unsigned long val;
-      __asm__ __volatile__ ("rdtsc" : "=A" (val));
-      return val;
-  }
- 
-#elif (defined(__GNUC__) && defined(__ppc__))
-
-  __inline__ sqlite_uint64 sqlite3Hwtime(void){
-      unsigned long long retval;
-      unsigned long junk;
-      __asm__ __volatile__ ("\n\
-          1:      mftbu   %1\n\
-                  mftb    %L0\n\
-                  mftbu   %0\n\
-                  cmpw    %0,%1\n\
-                  bne     1b"
-                  : "=r" (retval), "=r" (junk));
-      return retval;
-  }
-
-#else
-
-  #error Need implementation of sqlite3Hwtime() for your platform.
-
-  /*
-  ** To compile without implementing sqlite3Hwtime() for your platform,
-  ** you can remove the above #error and use the following
-  ** stub function.  You will lose timing support for many
-  ** of the debugging and testing utilities, but it should at
-  ** least compile and run.
-  */
-SQLITE_PRIVATE   sqlite_uint64 sqlite3Hwtime(void){ return ((sqlite_uint64)0); }
-
-#endif
-
-#endif /* !defined(_HWTIME_H_) */
-
-/************** End of hwtime.h **********************************************/
-/************** Continuing where we left off in os_common.h ******************/
-
-static sqlite_uint64 g_start;
-static sqlite_uint64 g_elapsed;
-#define TIMER_START       g_start=sqlite3Hwtime()
-#define TIMER_END         g_elapsed=sqlite3Hwtime()-g_start
-#define TIMER_ELAPSED     g_elapsed
-#else
-#define TIMER_START
-#define TIMER_END
-#define TIMER_ELAPSED     ((sqlite_uint64)0)
-#endif
-
-/*
-** If we compile with the SQLITE_TEST macro set, then the following block
-** of code will give us the ability to simulate a disk I/O error.  This
-** is used for testing the I/O recovery logic.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_io_error_hit = 0;            /* Total number of I/O Errors */
-SQLITE_API int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */
-SQLITE_API int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */
-SQLITE_API int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */
-SQLITE_API int sqlite3_io_error_benign = 0;         /* True if errors are benign */
-SQLITE_API int sqlite3_diskfull_pending = 0;
-SQLITE_API int sqlite3_diskfull = 0;
-#define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
-#define SimulateIOError(CODE)  \
-  if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
-       || sqlite3_io_error_pending-- == 1 )  \
-              { local_ioerr(); CODE; }
-static void local_ioerr(){
-  IOTRACE(("IOERR\n"));
-  sqlite3_io_error_hit++;
-  if( !sqlite3_io_error_benign ) sqlite3_io_error_hardhit++;
-}
-#define SimulateDiskfullError(CODE) \
-   if( sqlite3_diskfull_pending ){ \
-     if( sqlite3_diskfull_pending == 1 ){ \
-       local_ioerr(); \
-       sqlite3_diskfull = 1; \
-       sqlite3_io_error_hit = 1; \
-       CODE; \
-     }else{ \
-       sqlite3_diskfull_pending--; \
-     } \
-   }
-#else
-#define SimulateIOErrorBenign(X)
-#define SimulateIOError(A)
-#define SimulateDiskfullError(A)
-#endif
-
-/*
-** When testing, keep a count of the number of open files.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_open_file_count = 0;
-#define OpenCounter(X)  sqlite3_open_file_count+=(X)
-#else
-#define OpenCounter(X)
-#endif
-
-#endif /* !defined(_OS_COMMON_H_) */
-
-/************** End of os_common.h *******************************************/
-/************** Continuing where we left off in os_os2.c *********************/
-
-/* Forward references */
-typedef struct os2File os2File;         /* The file structure */
-typedef struct os2ShmNode os2ShmNode;   /* A shared descritive memory node */
-typedef struct os2ShmLink os2ShmLink;   /* A connection to shared-memory */
-
-/*
-** The os2File structure is subclass of sqlite3_file specific for the OS/2
-** protability layer.
-*/
-struct os2File {
-  const sqlite3_io_methods *pMethod;  /* Always the first entry */
-  HFILE h;                  /* Handle for accessing the file */
-  int flags;                /* Flags provided to os2Open() */
-  int locktype;             /* Type of lock currently held on this file */
-  int szChunk;              /* Chunk size configured by FCNTL_CHUNK_SIZE */
-  char *zFullPathCp;        /* Full path name of this file */
-  os2ShmLink *pShmLink;     /* Instance of shared memory on this file */
-};
-
-#define LOCK_TIMEOUT 10L /* the default locking timeout */
-
-/*
-** Missing from some versions of the OS/2 toolkit -
-** used to allocate from high memory if possible
-*/
-#ifndef OBJ_ANY
-# define OBJ_ANY 0x00000400
-#endif
-
-/*****************************************************************************
-** The next group of routines implement the I/O methods specified
-** by the sqlite3_io_methods object.
-******************************************************************************/
-
-/*
-** Close a file.
-*/
-static int os2Close( sqlite3_file *id ){
-  APIRET rc;
-  os2File *pFile = (os2File*)id;
-
-  assert( id!=0 );
-  OSTRACE(( "CLOSE %d (%s)\n", pFile->h, pFile->zFullPathCp ));
-
-  rc = DosClose( pFile->h );
-
-  if( pFile->flags & SQLITE_OPEN_DELETEONCLOSE )
-    DosForceDelete( (PSZ)pFile->zFullPathCp );
-
-  free( pFile->zFullPathCp );
-  pFile->zFullPathCp = NULL;
-  pFile->locktype = NO_LOCK;
-  pFile->h = (HFILE)-1;
-  pFile->flags = 0;
-
-  OpenCounter( -1 );
-  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
-}
-
-/*
-** Read data from a file into a buffer.  Return SQLITE_OK if all
-** bytes were read successfully and SQLITE_IOERR if anything goes
-** wrong.
-*/
-static int os2Read(
-  sqlite3_file *id,               /* File to read from */
-  void *pBuf,                     /* Write content into this buffer */
-  int amt,                        /* Number of bytes to read */
-  sqlite3_int64 offset            /* Begin reading at this offset */
-){
-  ULONG fileLocation = 0L;
-  ULONG got;
-  os2File *pFile = (os2File*)id;
-  assert( id!=0 );
-  SimulateIOError( return SQLITE_IOERR_READ );
-  OSTRACE(( "READ %d lock=%d\n", pFile->h, pFile->locktype ));
-  if( DosSetFilePtr(pFile->h, offset, FILE_BEGIN, &fileLocation) != NO_ERROR ){
-    return SQLITE_IOERR;
-  }
-  if( DosRead( pFile->h, pBuf, amt, &got ) != NO_ERROR ){
-    return SQLITE_IOERR_READ;
-  }
-  if( got == (ULONG)amt )
-    return SQLITE_OK;
-  else {
-    /* Unread portions of the input buffer must be zero-filled */
-    memset(&((char*)pBuf)[got], 0, amt-got);
-    return SQLITE_IOERR_SHORT_READ;
-  }
-}
-
-/*
-** Write data from a buffer into a file.  Return SQLITE_OK on success
-** or some other error code on failure.
-*/
-static int os2Write(
-  sqlite3_file *id,               /* File to write into */
-  const void *pBuf,               /* The bytes to be written */
-  int amt,                        /* Number of bytes to write */
-  sqlite3_int64 offset            /* Offset into the file to begin writing at */
-){
-  ULONG fileLocation = 0L;
-  APIRET rc = NO_ERROR;
-  ULONG wrote;
-  os2File *pFile = (os2File*)id;
-  assert( id!=0 );
-  SimulateIOError( return SQLITE_IOERR_WRITE );
-  SimulateDiskfullError( return SQLITE_FULL );
-  OSTRACE(( "WRITE %d lock=%d\n", pFile->h, pFile->locktype ));
-  if( DosSetFilePtr(pFile->h, offset, FILE_BEGIN, &fileLocation) != NO_ERROR ){
-    return SQLITE_IOERR;
-  }
-  assert( amt>0 );
-  while( amt > 0 &&
-         ( rc = DosWrite( pFile->h, (PVOID)pBuf, amt, &wrote ) ) == NO_ERROR &&
-         wrote > 0
-  ){
-    amt -= wrote;
-    pBuf = &((char*)pBuf)[wrote];
-  }
-
-  return ( rc != NO_ERROR || amt > (int)wrote ) ? SQLITE_FULL : SQLITE_OK;
-}
-
-/*
-** Truncate an open file to a specified size
-*/
-static int os2Truncate( sqlite3_file *id, i64 nByte ){
-  APIRET rc;
-  os2File *pFile = (os2File*)id;
-  assert( id!=0 );
-  OSTRACE(( "TRUNCATE %d %lld\n", pFile->h, nByte ));
-  SimulateIOError( return SQLITE_IOERR_TRUNCATE );
-
-  /* If the user has configured a chunk-size for this file, truncate the
-  ** file so that it consists of an integer number of chunks (i.e. the
-  ** actual file size after the operation may be larger than the requested
-  ** size).
-  */
-  if( pFile->szChunk ){
-    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
-  }
-  
-  rc = DosSetFileSize( pFile->h, nByte );
-  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR_TRUNCATE;
-}
-
-#ifdef SQLITE_TEST
-/*
-** Count the number of fullsyncs and normal syncs.  This is used to test
-** that syncs and fullsyncs are occuring at the right times.
-*/
-SQLITE_API int sqlite3_sync_count = 0;
-SQLITE_API int sqlite3_fullsync_count = 0;
-#endif
-
-/*
-** Make sure all writes to a particular file are committed to disk.
-*/
-static int os2Sync( sqlite3_file *id, int flags ){
-  os2File *pFile = (os2File*)id;
-  OSTRACE(( "SYNC %d lock=%d\n", pFile->h, pFile->locktype ));
-#ifdef SQLITE_TEST
-  if( flags & SQLITE_SYNC_FULL){
-    sqlite3_fullsync_count++;
-  }
-  sqlite3_sync_count++;
-#endif
-  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
-  ** no-op
-  */
-#ifdef SQLITE_NO_SYNC
-  UNUSED_PARAMETER(pFile);
-  return SQLITE_OK;
-#else
-  return DosResetBuffer( pFile->h ) == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
-#endif
-}
-
-/*
-** Determine the current size of a file in bytes
-*/
-static int os2FileSize( sqlite3_file *id, sqlite3_int64 *pSize ){
-  APIRET rc = NO_ERROR;
-  FILESTATUS3 fsts3FileInfo;
-  memset(&fsts3FileInfo, 0, sizeof(fsts3FileInfo));
-  assert( id!=0 );
-  SimulateIOError( return SQLITE_IOERR_FSTAT );
-  rc = DosQueryFileInfo( ((os2File*)id)->h, FIL_STANDARD, &fsts3FileInfo, sizeof(FILESTATUS3) );
-  if( rc == NO_ERROR ){
-    *pSize = fsts3FileInfo.cbFile;
-    return SQLITE_OK;
-  }else{
-    return SQLITE_IOERR_FSTAT;
-  }
-}
-
-/*
-** Acquire a reader lock.
-*/
-static int getReadLock( os2File *pFile ){
-  FILELOCK  LockArea,
-            UnlockArea;
-  APIRET res;
-  memset(&LockArea, 0, sizeof(LockArea));
-  memset(&UnlockArea, 0, sizeof(UnlockArea));
-  LockArea.lOffset = SHARED_FIRST;
-  LockArea.lRange = SHARED_SIZE;
-  UnlockArea.lOffset = 0L;
-  UnlockArea.lRange = 0L;
-  res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 1L );
-  OSTRACE(( "GETREADLOCK %d res=%d\n", pFile->h, res ));
-  return res;
-}
-
-/*
-** Undo a readlock
-*/
-static int unlockReadLock( os2File *id ){
-  FILELOCK  LockArea,
-            UnlockArea;
-  APIRET res;
-  memset(&LockArea, 0, sizeof(LockArea));
-  memset(&UnlockArea, 0, sizeof(UnlockArea));
-  LockArea.lOffset = 0L;
-  LockArea.lRange = 0L;
-  UnlockArea.lOffset = SHARED_FIRST;
-  UnlockArea.lRange = SHARED_SIZE;
-  res = DosSetFileLocks( id->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 1L );
-  OSTRACE(( "UNLOCK-READLOCK file handle=%d res=%d?\n", id->h, res ));
-  return res;
-}
-
-/*
-** Lock the file with the lock specified by parameter locktype - one
-** of the following:
-**
-**     (1) SHARED_LOCK
-**     (2) RESERVED_LOCK
-**     (3) PENDING_LOCK
-**     (4) EXCLUSIVE_LOCK
-**
-** Sometimes when requesting one lock state, additional lock states
-** are inserted in between.  The locking might fail on one of the later
-** transitions leaving the lock state different from what it started but
-** still short of its goal.  The following chart shows the allowed
-** transitions and the inserted intermediate states:
-**
-**    UNLOCKED -> SHARED
-**    SHARED -> RESERVED
-**    SHARED -> (PENDING) -> EXCLUSIVE
-**    RESERVED -> (PENDING) -> EXCLUSIVE
-**    PENDING -> EXCLUSIVE
-**
-** This routine will only increase a lock.  The os2Unlock() routine
-** erases all locks at once and returns us immediately to locking level 0.
-** It is not possible to lower the locking level one step at a time.  You
-** must go straight to locking level 0.
-*/
-static int os2Lock( sqlite3_file *id, int locktype ){
-  int rc = SQLITE_OK;       /* Return code from subroutines */
-  APIRET res = NO_ERROR;    /* Result of an OS/2 lock call */
-  int newLocktype;       /* Set pFile->locktype to this value before exiting */
-  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
-  FILELOCK  LockArea,
-            UnlockArea;
-  os2File *pFile = (os2File*)id;
-  memset(&LockArea, 0, sizeof(LockArea));
-  memset(&UnlockArea, 0, sizeof(UnlockArea));
-  assert( pFile!=0 );
-  OSTRACE(( "LOCK %d %d was %d\n", pFile->h, locktype, pFile->locktype ));
-
-  /* If there is already a lock of this type or more restrictive on the
-  ** os2File, do nothing. Don't use the end_lock: exit path, as
-  ** sqlite3_mutex_enter() hasn't been called yet.
-  */
-  if( pFile->locktype>=locktype ){
-    OSTRACE(( "LOCK %d %d ok (already held)\n", pFile->h, locktype ));
-    return SQLITE_OK;
-  }
-
-  /* Make sure the locking sequence is correct
-  */
-  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
-  assert( locktype!=PENDING_LOCK );
-  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );
-
-  /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
-  ** a SHARED lock.  If we are acquiring a SHARED lock, the acquisition of
-  ** the PENDING_LOCK byte is temporary.
-  */
-  newLocktype = pFile->locktype;
-  if( pFile->locktype==NO_LOCK
-      || (locktype==EXCLUSIVE_LOCK && pFile->locktype==RESERVED_LOCK)
-  ){
-    LockArea.lOffset = PENDING_BYTE;
-    LockArea.lRange = 1L;
-    UnlockArea.lOffset = 0L;
-    UnlockArea.lRange = 0L;
-
-    /* wait longer than LOCK_TIMEOUT here not to have to try multiple times */
-    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 100L, 0L );
-    if( res == NO_ERROR ){
-      gotPendingLock = 1;
-      OSTRACE(( "LOCK %d pending lock boolean set.  res=%d\n", pFile->h, res ));
-    }
-  }
-
-  /* Acquire a shared lock
-  */
-  if( locktype==SHARED_LOCK && res == NO_ERROR ){
-    assert( pFile->locktype==NO_LOCK );
-    res = getReadLock(pFile);
-    if( res == NO_ERROR ){
-      newLocktype = SHARED_LOCK;
-    }
-    OSTRACE(( "LOCK %d acquire shared lock. res=%d\n", pFile->h, res ));
-  }
-
-  /* Acquire a RESERVED lock
-  */
-  if( locktype==RESERVED_LOCK && res == NO_ERROR ){
-    assert( pFile->locktype==SHARED_LOCK );
-    LockArea.lOffset = RESERVED_BYTE;
-    LockArea.lRange = 1L;
-    UnlockArea.lOffset = 0L;
-    UnlockArea.lRange = 0L;
-    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
-    if( res == NO_ERROR ){
-      newLocktype = RESERVED_LOCK;
-    }
-    OSTRACE(( "LOCK %d acquire reserved lock. res=%d\n", pFile->h, res ));
-  }
-
-  /* Acquire a PENDING lock
-  */
-  if( locktype==EXCLUSIVE_LOCK && res == NO_ERROR ){
-    newLocktype = PENDING_LOCK;
-    gotPendingLock = 0;
-    OSTRACE(( "LOCK %d acquire pending lock. pending lock boolean unset.\n",
-               pFile->h ));
-  }
-
-  /* Acquire an EXCLUSIVE lock
-  */
-  if( locktype==EXCLUSIVE_LOCK && res == NO_ERROR ){
-    assert( pFile->locktype>=SHARED_LOCK );
-    res = unlockReadLock(pFile);
-    OSTRACE(( "unreadlock = %d\n", res ));
-    LockArea.lOffset = SHARED_FIRST;
-    LockArea.lRange = SHARED_SIZE;
-    UnlockArea.lOffset = 0L;
-    UnlockArea.lRange = 0L;
-    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
-    if( res == NO_ERROR ){
-      newLocktype = EXCLUSIVE_LOCK;
-    }else{
-      OSTRACE(( "OS/2 error-code = %d\n", res ));
-      getReadLock(pFile);
-    }
-    OSTRACE(( "LOCK %d acquire exclusive lock.  res=%d\n", pFile->h, res ));
-  }
-
-  /* If we are holding a PENDING lock that ought to be released, then
-  ** release it now.
-  */
-  if( gotPendingLock && locktype==SHARED_LOCK ){
-    int r;
-    LockArea.lOffset = 0L;
-    LockArea.lRange = 0L;
-    UnlockArea.lOffset = PENDING_BYTE;
-    UnlockArea.lRange = 1L;
-    r = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
-    OSTRACE(( "LOCK %d unlocking pending/is shared. r=%d\n", pFile->h, r ));
-  }
-
-  /* Update the state of the lock has held in the file descriptor then
-  ** return the appropriate result code.
-  */
-  if( res == NO_ERROR ){
-    rc = SQLITE_OK;
-  }else{
-    OSTRACE(( "LOCK FAILED %d trying for %d but got %d\n", pFile->h,
-              locktype, newLocktype ));
-    rc = SQLITE_BUSY;
-  }
-  pFile->locktype = newLocktype;
-  OSTRACE(( "LOCK %d now %d\n", pFile->h, pFile->locktype ));
-  return rc;
-}
-
-/*
-** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, return
-** non-zero, otherwise zero.
-*/
-static int os2CheckReservedLock( sqlite3_file *id, int *pOut ){
-  int r = 0;
-  os2File *pFile = (os2File*)id;
-  assert( pFile!=0 );
-  if( pFile->locktype>=RESERVED_LOCK ){
-    r = 1;
-    OSTRACE(( "TEST WR-LOCK %d %d (local)\n", pFile->h, r ));
-  }else{
-    FILELOCK  LockArea,
-              UnlockArea;
-    APIRET rc = NO_ERROR;
-    memset(&LockArea, 0, sizeof(LockArea));
-    memset(&UnlockArea, 0, sizeof(UnlockArea));
-    LockArea.lOffset = RESERVED_BYTE;
-    LockArea.lRange = 1L;
-    UnlockArea.lOffset = 0L;
-    UnlockArea.lRange = 0L;
-    rc = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
-    OSTRACE(( "TEST WR-LOCK %d lock reserved byte rc=%d\n", pFile->h, rc ));
-    if( rc == NO_ERROR ){
-      APIRET rcu = NO_ERROR; /* return code for unlocking */
-      LockArea.lOffset = 0L;
-      LockArea.lRange = 0L;
-      UnlockArea.lOffset = RESERVED_BYTE;
-      UnlockArea.lRange = 1L;
-      rcu = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
-      OSTRACE(( "TEST WR-LOCK %d unlock reserved byte r=%d\n", pFile->h, rcu ));
-    }
-    r = !(rc == NO_ERROR);
-    OSTRACE(( "TEST WR-LOCK %d %d (remote)\n", pFile->h, r ));
-  }
-  *pOut = r;
-  return SQLITE_OK;
-}
-
-/*
-** Lower the locking level on file descriptor id to locktype.  locktype
-** must be either NO_LOCK or SHARED_LOCK.
-**
-** If the locking level of the file descriptor is already at or below
-** the requested locking level, this routine is a no-op.
-**
-** It is not possible for this routine to fail if the second argument
-** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
-** might return SQLITE_IOERR;
-*/
-static int os2Unlock( sqlite3_file *id, int locktype ){
-  int type;
-  os2File *pFile = (os2File*)id;
-  APIRET rc = SQLITE_OK;
-  APIRET res = NO_ERROR;
-  FILELOCK  LockArea,
-            UnlockArea;
-  memset(&LockArea, 0, sizeof(LockArea));
-  memset(&UnlockArea, 0, sizeof(UnlockArea));
-  assert( pFile!=0 );
-  assert( locktype<=SHARED_LOCK );
-  OSTRACE(( "UNLOCK %d to %d was %d\n", pFile->h, locktype, pFile->locktype ));
-  type = pFile->locktype;
-  if( type>=EXCLUSIVE_LOCK ){
-    LockArea.lOffset = 0L;
-    LockArea.lRange = 0L;
-    UnlockArea.lOffset = SHARED_FIRST;
-    UnlockArea.lRange = SHARED_SIZE;
-    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
-    OSTRACE(( "UNLOCK %d exclusive lock res=%d\n", pFile->h, res ));
-    if( locktype==SHARED_LOCK && getReadLock(pFile) != NO_ERROR ){
-      /* This should never happen.  We should always be able to
-      ** reacquire the read lock */
-      OSTRACE(( "UNLOCK %d to %d getReadLock() failed\n", pFile->h, locktype ));
-      rc = SQLITE_IOERR_UNLOCK;
-    }
-  }
-  if( type>=RESERVED_LOCK ){
-    LockArea.lOffset = 0L;
-    LockArea.lRange = 0L;
-    UnlockArea.lOffset = RESERVED_BYTE;
-    UnlockArea.lRange = 1L;
-    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
-    OSTRACE(( "UNLOCK %d reserved res=%d\n", pFile->h, res ));
-  }
-  if( locktype==NO_LOCK && type>=SHARED_LOCK ){
-    res = unlockReadLock(pFile);
-    OSTRACE(( "UNLOCK %d is %d want %d res=%d\n",
-              pFile->h, type, locktype, res ));
-  }
-  if( type>=PENDING_LOCK ){
-    LockArea.lOffset = 0L;
-    LockArea.lRange = 0L;
-    UnlockArea.lOffset = PENDING_BYTE;
-    UnlockArea.lRange = 1L;
-    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
-    OSTRACE(( "UNLOCK %d pending res=%d\n", pFile->h, res ));
-  }
-  pFile->locktype = locktype;
-  OSTRACE(( "UNLOCK %d now %d\n", pFile->h, pFile->locktype ));
-  return rc;
-}
-
-/*
-** Control and query of the open file handle.
-*/
-static int os2FileControl(sqlite3_file *id, int op, void *pArg){
-  switch( op ){
-    case SQLITE_FCNTL_LOCKSTATE: {
-      *(int*)pArg = ((os2File*)id)->locktype;
-      OSTRACE(( "FCNTL_LOCKSTATE %d lock=%d\n",
-                ((os2File*)id)->h, ((os2File*)id)->locktype ));
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_CHUNK_SIZE: {
-      ((os2File*)id)->szChunk = *(int*)pArg;
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_SIZE_HINT: {
-      sqlite3_int64 sz = *(sqlite3_int64*)pArg;
-      SimulateIOErrorBenign(1);
-      os2Truncate(id, sz);
-      SimulateIOErrorBenign(0);
-      return SQLITE_OK;
-    }
-    case SQLITE_FCNTL_SYNC_OMITTED: {
-      return SQLITE_OK;
-    }
-  }
-  return SQLITE_NOTFOUND;
-}
-
-/*
-** Return the sector size in bytes of the underlying block device for
-** the specified file. This is almost always 512 bytes, but may be
-** larger for some devices.
-**
-** SQLite code assumes this function cannot fail. It also assumes that
-** if two files are created in the same file-system directory (i.e.
-** a database and its journal file) that the sector size will be the
-** same for both.
-*/
-static int os2SectorSize(sqlite3_file *id){
-  UNUSED_PARAMETER(id);
-  return SQLITE_DEFAULT_SECTOR_SIZE;
-}
-
-/*
-** Return a vector of device characteristics.
-*/
-static int os2DeviceCharacteristics(sqlite3_file *id){
-  UNUSED_PARAMETER(id);
-  return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN;
-}
-
-
-/*
-** Character set conversion objects used by conversion routines.
-*/
-static UconvObject ucUtf8 = NULL; /* convert between UTF-8 and UCS-2 */
-static UconvObject uclCp = NULL;  /* convert between local codepage and UCS-2 */
-
-/*
-** Helper function to initialize the conversion objects from and to UTF-8.
-*/
-static void initUconvObjects( void ){
-  if( UniCreateUconvObject( UTF_8, &ucUtf8 ) != ULS_SUCCESS )
-    ucUtf8 = NULL;
-  if ( UniCreateUconvObject( (UniChar *)L"@path=yes", &uclCp ) != ULS_SUCCESS )
-    uclCp = NULL;
-}
-
-/*
-** Helper function to free the conversion objects from and to UTF-8.
-*/
-static void freeUconvObjects( void ){
-  if ( ucUtf8 )
-    UniFreeUconvObject( ucUtf8 );
-  if ( uclCp )
-    UniFreeUconvObject( uclCp );
-  ucUtf8 = NULL;
-  uclCp = NULL;
-}
-
-/*
-** Helper function to convert UTF-8 filenames to local OS/2 codepage.
-** The two-step process: first convert the incoming UTF-8 string
-** into UCS-2 and then from UCS-2 to the current codepage.
-** The returned char pointer has to be freed.
-*/
-static char *convertUtf8PathToCp( const char *in ){
-  UniChar tempPath[CCHMAXPATH];
-  char *out = (char *)calloc( CCHMAXPATH, 1 );
-
-  if( !out )
-    return NULL;
-
-  if( !ucUtf8 || !uclCp )
-    initUconvObjects();
-
-  /* determine string for the conversion of UTF-8 which is CP1208 */
-  if( UniStrToUcs( ucUtf8, tempPath, (char *)in, CCHMAXPATH ) != ULS_SUCCESS )
-    return out; /* if conversion fails, return the empty string */
-
-  /* conversion for current codepage which can be used for paths */
-  UniStrFromUcs( uclCp, out, tempPath, CCHMAXPATH );
-
-  return out;
-}
-
-/*
-** Helper function to convert filenames from local codepage to UTF-8.
-** The two-step process: first convert the incoming codepage-specific
-** string into UCS-2 and then from UCS-2 to the codepage of UTF-8.
-** The returned char pointer has to be freed.
-**
-** This function is non-static to be able to use this in shell.c and
-** similar applications that take command line arguments.
-*/
-char *convertCpPathToUtf8( const char *in ){
-  UniChar tempPath[CCHMAXPATH];
-  char *out = (char *)calloc( CCHMAXPATH, 1 );
-
-  if( !out )
-    return NULL;
-
-  if( !ucUtf8 || !uclCp )
-    initUconvObjects();
-
-  /* conversion for current codepage which can be used for paths */
-  if( UniStrToUcs( uclCp, tempPath, (char *)in, CCHMAXPATH ) != ULS_SUCCESS )
-    return out; /* if conversion fails, return the empty string */
-
-  /* determine string for the conversion of UTF-8 which is CP1208 */
-  UniStrFromUcs( ucUtf8, out, tempPath, CCHMAXPATH );
-
-  return out;
-}
-
-
-#ifndef SQLITE_OMIT_WAL
-
-/*
-** Use main database file for interprocess locking. If un-defined
-** a separate file is created for this purpose. The file will be
-** used only to set file locks. There will be no data written to it.
-*/
-#define SQLITE_OS2_NO_WAL_LOCK_FILE     
-
-#if 0
-static void _ERR_TRACE( const char *fmt, ... ) {
-  va_list  ap;
-  va_start(ap, fmt);
-  vfprintf(stderr, fmt, ap);
-  fflush(stderr);
-}
-#define ERR_TRACE(rc, msg)        \
-        if( (rc) != SQLITE_OK ) _ERR_TRACE msg;
-#else
-#define ERR_TRACE(rc, msg)
-#endif
-
-/*
-** Helper functions to obtain and relinquish the global mutex. The
-** global mutex is used to protect os2ShmNodeList.
-**
-** Function os2ShmMutexHeld() is used to assert() that the global mutex 
-** is held when required. This function is only used as part of assert() 
-** statements. e.g.
-**
-**   os2ShmEnterMutex()
-**     assert( os2ShmMutexHeld() );
-**   os2ShmLeaveMutex()
-*/
-static void os2ShmEnterMutex(void){
-  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-static void os2ShmLeaveMutex(void){
-  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-#ifdef SQLITE_DEBUG
-static int os2ShmMutexHeld(void) {
-  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
-}
-int GetCurrentProcessId(void) {
-  PPIB pib;
-  DosGetInfoBlocks(NULL, &pib);
-  return (int)pib->pib_ulpid;
-}
-#endif
-
-/*
-** Object used to represent a the shared memory area for a single log file.
-** When multiple threads all reference the same log-summary, each thread has
-** its own os2File object, but they all point to a single instance of this 
-** object.  In other words, each log-summary is opened only once per process.
-**
-** os2ShmMutexHeld() must be true when creating or destroying
-** this object or while reading or writing the following fields:
-**
-**      nRef
-**      pNext 
-**
-** The following fields are read-only after the object is created:
-** 
-**      szRegion
-**      hLockFile
-**      shmBaseName
-**
-** Either os2ShmNode.mutex must be held or os2ShmNode.nRef==0 and
-** os2ShmMutexHeld() is true when reading or writing any other field
-** in this structure.
-**
-*/
-struct os2ShmNode {
-  sqlite3_mutex *mutex;      /* Mutex to access this object */
-  os2ShmNode *pNext;         /* Next in list of all os2ShmNode objects */
-
-  int szRegion;              /* Size of shared-memory regions */
-
-  int nRegion;               /* Size of array apRegion */
-  void **apRegion;           /* Array of pointers to shared-memory regions */
-
-  int nRef;                  /* Number of os2ShmLink objects pointing to this */
-  os2ShmLink *pFirst;        /* First os2ShmLink object pointing to this */
-
-  HFILE hLockFile;           /* File used for inter-process memory locking */
-  char shmBaseName[1];       /* Name of the memory object !!! must last !!! */
-};
-
-
-/*
-** Structure used internally by this VFS to record the state of an
-** open shared memory connection.
-**
-** The following fields are initialized when this object is created and
-** are read-only thereafter:
-**
-**    os2Shm.pShmNode
-**    os2Shm.id
-**
-** All other fields are read/write.  The os2Shm.pShmNode->mutex must be held
-** while accessing any read/write fields.
-*/
-struct os2ShmLink {
-  os2ShmNode *pShmNode;      /* The underlying os2ShmNode object */
-  os2ShmLink *pNext;         /* Next os2Shm with the same os2ShmNode */
-  u32 sharedMask;            /* Mask of shared locks held */
-  u32 exclMask;              /* Mask of exclusive locks held */
-#ifdef SQLITE_DEBUG
-  u8 id;                     /* Id of this connection with its os2ShmNode */
-#endif
-};
-
-
-/*
-** A global list of all os2ShmNode objects.
-**
-** The os2ShmMutexHeld() must be true while reading or writing this list.
-*/
-static os2ShmNode *os2ShmNodeList = NULL;
-
-/*
-** Constants used for locking
-*/
-#ifdef  SQLITE_OS2_NO_WAL_LOCK_FILE
-#define OS2_SHM_BASE   (PENDING_BYTE + 0x10000)         /* first lock byte */
-#else
-#define OS2_SHM_BASE   ((22+SQLITE_SHM_NLOCK)*4)        /* first lock byte */
-#endif
-
-#define OS2_SHM_DMS    (OS2_SHM_BASE+SQLITE_SHM_NLOCK)  /* deadman switch */
-
-/*
-** Apply advisory locks for all n bytes beginning at ofst.
-*/
-#define _SHM_UNLCK  1   /* no lock */
-#define _SHM_RDLCK  2   /* shared lock, no wait */
-#define _SHM_WRLCK  3   /* exlusive lock, no wait */
-#define _SHM_WRLCK_WAIT 4 /* exclusive lock, wait */
-static int os2ShmSystemLock(
-  os2ShmNode *pNode,    /* Apply locks to this open shared-memory segment */
-  int lockType,         /* _SHM_UNLCK, _SHM_RDLCK, _SHM_WRLCK or _SHM_WRLCK_WAIT */
-  int ofst,             /* Offset to first byte to be locked/unlocked */
-  int nByte             /* Number of bytes to lock or unlock */
-){
-  APIRET rc;
-  FILELOCK area;
-  ULONG mode, timeout;
-
-  /* Access to the os2ShmNode object is serialized by the caller */
-  assert( sqlite3_mutex_held(pNode->mutex) || pNode->nRef==0 );
-
-  mode = 1;     /* shared lock */
-  timeout = 0;  /* no wait */
-  area.lOffset = ofst;
-  area.lRange = nByte;
-
-  switch( lockType ) {
-    case _SHM_WRLCK_WAIT:
-      timeout = (ULONG)-1;      /* wait forever */
-    case _SHM_WRLCK:
-      mode = 0;                 /* exclusive lock */
-    case _SHM_RDLCK:
-      rc = DosSetFileLocks(pNode->hLockFile, 
-                           NULL, &area, timeout, mode);
-      break;
-    /* case _SHM_UNLCK: */
-    default:
-      rc = DosSetFileLocks(pNode->hLockFile, 
-                           &area, NULL, 0, 0);
-      break;
-  }
-                          
-  OSTRACE(("SHM-LOCK %d %s %s 0x%08lx\n", 
-           pNode->hLockFile,
-           rc==SQLITE_OK ? "ok" : "failed",
-           lockType==_SHM_UNLCK ? "Unlock" : "Lock",
-           rc));
-
-  ERR_TRACE(rc, ("os2ShmSystemLock: %d %s\n", rc, pNode->shmBaseName))
-
-  return ( rc == 0 ) ?  SQLITE_OK : SQLITE_BUSY;
-}
-
-/*
-** Find an os2ShmNode in global list or allocate a new one, if not found.
-**
-** This is not a VFS shared-memory method; it is a utility function called
-** by VFS shared-memory methods.
-*/
-static int os2OpenSharedMemory( os2File *fd, int szRegion ) {
-  os2ShmLink *pLink;
-  os2ShmNode *pNode;
-  int cbShmName, rc = SQLITE_OK;
-  char shmName[CCHMAXPATH + 30];
-#ifndef SQLITE_OS2_NO_WAL_LOCK_FILE
-  ULONG action;
-#endif
-  
-  /* We need some additional space at the end to append the region number */
-  cbShmName = sprintf(shmName, "\\SHAREMEM\\%s", fd->zFullPathCp );
-  if( cbShmName >= CCHMAXPATH-8 )
-    return SQLITE_IOERR_SHMOPEN; 
-
-  /* Replace colon in file name to form a valid shared memory name */
-  shmName[10+1] = '!';
-
-  /* Allocate link object (we free it later in case of failure) */
-  pLink = sqlite3_malloc( sizeof(*pLink) );
-  if( !pLink )
-    return SQLITE_NOMEM;
-
-  /* Access node list */
-  os2ShmEnterMutex();
-
-  /* Find node by it's shared memory base name */
-  for( pNode = os2ShmNodeList; 
-       pNode && stricmp(shmName, pNode->shmBaseName) != 0; 
-       pNode = pNode->pNext )   ;
-
-  /* Not found: allocate a new node */
-  if( !pNode ) {
-    pNode = sqlite3_malloc( sizeof(*pNode) + cbShmName );
-    if( pNode ) {
-      memset(pNode, 0, sizeof(*pNode) );
-      pNode->szRegion = szRegion;
-      pNode->hLockFile = (HFILE)-1;      
-      strcpy(pNode->shmBaseName, shmName);
-
-#ifdef SQLITE_OS2_NO_WAL_LOCK_FILE
-      if( DosDupHandle(fd->h, &pNode->hLockFile) != 0 ) {
-#else
-      sprintf(shmName, "%s-lck", fd->zFullPathCp);
-      if( DosOpen((PSZ)shmName, &pNode->hLockFile, &action, 0, FILE_NORMAL, 
-                  OPEN_ACTION_OPEN_IF_EXISTS | OPEN_ACTION_CREATE_IF_NEW,
-                  OPEN_ACCESS_READWRITE | OPEN_SHARE_DENYNONE | 
-                  OPEN_FLAGS_NOINHERIT | OPEN_FLAGS_FAIL_ON_ERROR,
-                  NULL) != 0 ) {
-#endif
-        sqlite3_free(pNode);  
-        rc = SQLITE_IOERR;
-      } else {
-        pNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
-        if( !pNode->mutex ) {
-          sqlite3_free(pNode);  
-          rc = SQLITE_NOMEM;
-        }
-      }   
-    } else {
-      rc = SQLITE_NOMEM;
-    }
-    
-    if( rc == SQLITE_OK ) {
-      pNode->pNext = os2ShmNodeList;
-      os2ShmNodeList = pNode;
-    } else {
-      pNode = NULL;
-    }
-  } else if( pNode->szRegion != szRegion ) {
-    rc = SQLITE_IOERR_SHMSIZE;
-    pNode = NULL;
-  }
-
-  if( pNode ) {
-    sqlite3_mutex_enter(pNode->mutex);
-
-    memset(pLink, 0, sizeof(*pLink));
-
-    pLink->pShmNode = pNode;
-    pLink->pNext = pNode->pFirst;
-    pNode->pFirst = pLink;
-    pNode->nRef++;
-
-    fd->pShmLink = pLink;
-
-    sqlite3_mutex_leave(pNode->mutex);
-    
-  } else {
-    /* Error occured. Free our link object. */
-    sqlite3_free(pLink);  
-  }
-
-  os2ShmLeaveMutex();
-
-  ERR_TRACE(rc, ("os2OpenSharedMemory: %d  %s\n", rc, fd->zFullPathCp))  
-  
-  return rc;
-}
-
-/*
-** Purge the os2ShmNodeList list of all entries with nRef==0.
-**
-** This is not a VFS shared-memory method; it is a utility function called
-** by VFS shared-memory methods.
-*/
-static void os2PurgeShmNodes( int deleteFlag ) {
-  os2ShmNode *pNode;
-  os2ShmNode **ppNode;
-
-  os2ShmEnterMutex();
-  
-  ppNode = &os2ShmNodeList;
-
-  while( *ppNode ) {
-    pNode = *ppNode;
-
-    if( pNode->nRef == 0 ) {
-      *ppNode = pNode->pNext;   
-     
-      if( pNode->apRegion ) {
-        /* Prevent other processes from resizing the shared memory */
-        os2ShmSystemLock(pNode, _SHM_WRLCK_WAIT, OS2_SHM_DMS, 1);
-
-        while( pNode->nRegion-- ) {
-#ifdef SQLITE_DEBUG
-          int rc = 
-#endif          
-          DosFreeMem(pNode->apRegion[pNode->nRegion]);
-
-          OSTRACE(("SHM-PURGE pid-%d unmap region=%d %s\n",
-                  (int)GetCurrentProcessId(), pNode->nRegion,
-                  rc == 0 ? "ok" : "failed"));
-        }
-
-        /* Allow other processes to resize the shared memory */
-        os2ShmSystemLock(pNode, _SHM_UNLCK, OS2_SHM_DMS, 1);
-
-        sqlite3_free(pNode->apRegion);
-      }  
-
-      DosClose(pNode->hLockFile);
-      
-#ifndef SQLITE_OS2_NO_WAL_LOCK_FILE
-      if( deleteFlag ) {
-         char fileName[CCHMAXPATH];
-         /* Skip "\\SHAREMEM\\" */
-         sprintf(fileName, "%s-lck", pNode->shmBaseName + 10);
-         /* restore colon */
-         fileName[1] = ':';
-         
-         DosForceDelete(fileName); 
-      }
-#endif
-
-      sqlite3_mutex_free(pNode->mutex);
-
-      sqlite3_free(pNode);
-      
-    } else {
-      ppNode = &pNode->pNext;
-    }
-  } 
-
-  os2ShmLeaveMutex();
-}
-
-/*
-** This function is called to obtain a pointer to region iRegion of the
-** shared-memory associated with the database file id. Shared-memory regions
-** are numbered starting from zero. Each shared-memory region is szRegion
-** bytes in size.
-**
-** If an error occurs, an error code is returned and *pp is set to NULL.
-**
-** Otherwise, if the bExtend parameter is 0 and the requested shared-memory
-** region has not been allocated (by any client, including one running in a
-** separate process), then *pp is set to NULL and SQLITE_OK returned. If
-** bExtend is non-zero and the requested shared-memory region has not yet
-** been allocated, it is allocated by this function.
-**
-** If the shared-memory region has already been allocated or is allocated by
-** this call as described above, then it is mapped into this processes
-** address space (if it is not already), *pp is set to point to the mapped
-** memory and SQLITE_OK returned.
-*/
-static int os2ShmMap(
-  sqlite3_file *id,               /* Handle open on database file */
-  int iRegion,                    /* Region to retrieve */
-  int szRegion,                   /* Size of regions */
-  int bExtend,                    /* True to extend block if necessary */
-  void volatile **pp              /* OUT: Mapped memory */
-){
-  PVOID pvTemp;
-  void **apRegion;
-  os2ShmNode *pNode;
-  int n, rc = SQLITE_OK;
-  char shmName[CCHMAXPATH];
-  os2File *pFile = (os2File*)id;
-  
-  *pp = NULL;
-
-  if( !pFile->pShmLink )
-    rc = os2OpenSharedMemory( pFile, szRegion );
-  
-  if( rc == SQLITE_OK ) {
-    pNode = pFile->pShmLink->pShmNode ;
-    
-    sqlite3_mutex_enter(pNode->mutex);
-    
-    assert( szRegion==pNode->szRegion );
-
-    /* Unmapped region ? */
-    if( iRegion >= pNode->nRegion ) {
-      /* Prevent other processes from resizing the shared memory */
-      os2ShmSystemLock(pNode, _SHM_WRLCK_WAIT, OS2_SHM_DMS, 1);
-
-      apRegion = sqlite3_realloc(
-        pNode->apRegion, (iRegion + 1) * sizeof(apRegion[0]));
-
-      if( apRegion ) {
-        pNode->apRegion = apRegion;
-
-        while( pNode->nRegion <= iRegion ) {
-          sprintf(shmName, "%s-%u", 
-                  pNode->shmBaseName, pNode->nRegion);
-
-          if( DosGetNamedSharedMem(&pvTemp, (PSZ)shmName, 
-                PAG_READ | PAG_WRITE) != NO_ERROR ) {
-            if( !bExtend )
-              break;
-
-            if( DosAllocSharedMem(&pvTemp, (PSZ)shmName, szRegion,
-                  PAG_READ | PAG_WRITE | PAG_COMMIT | OBJ_ANY) != NO_ERROR && 
-                DosAllocSharedMem(&pvTemp, (PSZ)shmName, szRegion,
-                  PAG_READ | PAG_WRITE | PAG_COMMIT) != NO_ERROR ) { 
-              rc = SQLITE_NOMEM;
-              break;
-            }
-          }
-
-          apRegion[pNode->nRegion++] = pvTemp;
-        }
-
-        /* zero out remaining entries */ 
-        for( n = pNode->nRegion; n <= iRegion; n++ )
-          pNode->apRegion[n] = NULL;
-
-        /* Return this region (maybe zero) */
-        *pp = pNode->apRegion[iRegion];
-      } else {
-        rc = SQLITE_NOMEM;
-      }
-
-      /* Allow other processes to resize the shared memory */
-      os2ShmSystemLock(pNode, _SHM_UNLCK, OS2_SHM_DMS, 1);
-      
-    } else {
-      /* Region has been mapped previously */
-      *pp = pNode->apRegion[iRegion];
-    }
-
-    sqlite3_mutex_leave(pNode->mutex);
-  } 
-
-  ERR_TRACE(rc, ("os2ShmMap: %s iRgn = %d, szRgn = %d, bExt = %d : %d\n", 
-                 pFile->zFullPathCp, iRegion, szRegion, bExtend, rc))
-          
-  return rc;
-}
-
-/*
-** Close a connection to shared-memory.  Delete the underlying
-** storage if deleteFlag is true.
-**
-** If there is no shared memory associated with the connection then this
-** routine is a harmless no-op.
-*/
-static int os2ShmUnmap(
-  sqlite3_file *id,               /* The underlying database file */
-  int deleteFlag                  /* Delete shared-memory if true */
-){
-  os2File *pFile = (os2File*)id;
-  os2ShmLink *pLink = pFile->pShmLink;
-  
-  if( pLink ) {
-    int nRef = -1;
-    os2ShmLink **ppLink;
-    os2ShmNode *pNode = pLink->pShmNode;
-
-    sqlite3_mutex_enter(pNode->mutex);
-    
-    for( ppLink = &pNode->pFirst;
-         *ppLink && *ppLink != pLink;
-         ppLink = &(*ppLink)->pNext )   ;
-         
-    assert(*ppLink);
-
-    if( *ppLink ) {
-      *ppLink = pLink->pNext;
-      nRef = --pNode->nRef;
-    } else {
-      ERR_TRACE(1, ("os2ShmUnmap: link not found ! %s\n", 
-                    pNode->shmBaseName))
-    }
-    
-    pFile->pShmLink = NULL;
-    sqlite3_free(pLink);
-
-    sqlite3_mutex_leave(pNode->mutex);
-    
-    if( nRef == 0 )
-      os2PurgeShmNodes( deleteFlag );
-  }
-
-  return SQLITE_OK;
-}
-
-/*
-** Change the lock state for a shared-memory segment.
-**
-** Note that the relationship between SHAREd and EXCLUSIVE locks is a little
-** different here than in posix.  In xShmLock(), one can go from unlocked
-** to shared and back or from unlocked to exclusive and back.  But one may
-** not go from shared to exclusive or from exclusive to shared.
-*/
-static int os2ShmLock(
-  sqlite3_file *id,          /* Database file holding the shared memory */
-  int ofst,                  /* First lock to acquire or release */
-  int n,                     /* Number of locks to acquire or release */
-  int flags                  /* What to do with the lock */
-){
-  u32 mask;                             /* Mask of locks to take or release */
-  int rc = SQLITE_OK;                   /* Result code */
-  os2File *pFile = (os2File*)id;
-  os2ShmLink *p = pFile->pShmLink;      /* The shared memory being locked */
-  os2ShmLink *pX;                       /* For looping over all siblings */
-  os2ShmNode *pShmNode = p->pShmNode;   /* Our node */
-  
-  assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
-  assert( n>=1 );
-  assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
-       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
-  assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
-
-  mask = (u32)((1U<<(ofst+n)) - (1U<<ofst));
-  assert( n>1 || mask==(1<<ofst) );
-
-
-  sqlite3_mutex_enter(pShmNode->mutex);
-
-  if( flags & SQLITE_SHM_UNLOCK ){
-    u32 allMask = 0; /* Mask of locks held by siblings */
-
-    /* See if any siblings hold this same lock */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( pX==p ) continue;
-      assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
-      allMask |= pX->sharedMask;
-    }
-
-    /* Unlock the system-level locks */
-    if( (mask & allMask)==0 ){
-      rc = os2ShmSystemLock(pShmNode, _SHM_UNLCK, ofst+OS2_SHM_BASE, n);
-    }else{
-      rc = SQLITE_OK;
-    }
-
-    /* Undo the local locks */
-    if( rc==SQLITE_OK ){
-      p->exclMask &= ~mask;
-      p->sharedMask &= ~mask;
-    } 
-  }else if( flags & SQLITE_SHM_SHARED ){
-    u32 allShared = 0;  /* Union of locks held by connections other than "p" */
-
-    /* Find out which shared locks are already held by sibling connections.
-    ** If any sibling already holds an exclusive lock, go ahead and return
-    ** SQLITE_BUSY.
-    */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( (pX->exclMask & mask)!=0 ){
-        rc = SQLITE_BUSY;
-        break;
-      }
-      allShared |= pX->sharedMask;
-    }
-
-    /* Get shared locks at the system level, if necessary */
-    if( rc==SQLITE_OK ){
-      if( (allShared & mask)==0 ){
-        rc = os2ShmSystemLock(pShmNode, _SHM_RDLCK, ofst+OS2_SHM_BASE, n);
-      }else{
-        rc = SQLITE_OK;
-      }
-    }
-
-    /* Get the local shared locks */
-    if( rc==SQLITE_OK ){
-      p->sharedMask |= mask;
-    }
-  }else{
-    /* Make sure no sibling connections hold locks that will block this
-    ** lock.  If any do, return SQLITE_BUSY right away.
-    */
-    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
-      if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
-        rc = SQLITE_BUSY;
-        break;
-      }
-    }
-  
-    /* Get the exclusive locks at the system level.  Then if successful
-    ** also mark the local connection as being locked.
-    */
-    if( rc==SQLITE_OK ){
-      rc = os2ShmSystemLock(pShmNode, _SHM_WRLCK, ofst+OS2_SHM_BASE, n);
-      if( rc==SQLITE_OK ){
-        assert( (p->sharedMask & mask)==0 );
-        p->exclMask |= mask;
-      }
-    }
-  }
-
-  sqlite3_mutex_leave(pShmNode->mutex);
-  
-  OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x %s\n",
-           p->id, (int)GetCurrentProcessId(), p->sharedMask, p->exclMask,
-           rc ? "failed" : "ok"));
-
-  ERR_TRACE(rc, ("os2ShmLock: ofst = %d, n = %d, flags = 0x%x -> %d \n", 
-                 ofst, n, flags, rc))
-                  
-  return rc; 
-}
-
-/*
-** Implement a memory barrier or memory fence on shared memory.
-**
-** All loads and stores begun before the barrier must complete before
-** any load or store begun after the barrier.
-*/
-static void os2ShmBarrier(
-  sqlite3_file *id                /* Database file holding the shared memory */
-){
-  UNUSED_PARAMETER(id);
-  os2ShmEnterMutex();
-  os2ShmLeaveMutex();
-}
-
-#else
-# define os2ShmMap     0
-# define os2ShmLock    0
-# define os2ShmBarrier 0
-# define os2ShmUnmap   0
-#endif /* #ifndef SQLITE_OMIT_WAL */
-
-
-/*
-** This vector defines all the methods that can operate on an
-** sqlite3_file for os2.
-*/
-static const sqlite3_io_methods os2IoMethod = {
-  2,                              /* iVersion */
-  os2Close,                       /* xClose */
-  os2Read,                        /* xRead */
-  os2Write,                       /* xWrite */
-  os2Truncate,                    /* xTruncate */
-  os2Sync,                        /* xSync */
-  os2FileSize,                    /* xFileSize */
-  os2Lock,                        /* xLock */
-  os2Unlock,                      /* xUnlock */
-  os2CheckReservedLock,           /* xCheckReservedLock */
-  os2FileControl,                 /* xFileControl */
-  os2SectorSize,                  /* xSectorSize */
-  os2DeviceCharacteristics,       /* xDeviceCharacteristics */
-  os2ShmMap,                      /* xShmMap */
-  os2ShmLock,                     /* xShmLock */
-  os2ShmBarrier,                  /* xShmBarrier */
-  os2ShmUnmap                     /* xShmUnmap */
-};
-
-
-/***************************************************************************
-** Here ends the I/O methods that form the sqlite3_io_methods object.
-**
-** The next block of code implements the VFS methods.
-****************************************************************************/
-
-/*
-** Create a temporary file name in zBuf.  zBuf must be big enough to
-** hold at pVfs->mxPathname characters.
-*/
-static int getTempname(int nBuf, char *zBuf ){
-  static const char zChars[] =
-    "abcdefghijklmnopqrstuvwxyz"
-    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-    "0123456789";
-  int i, j;
-  PSZ zTempPathCp;      
-  char zTempPath[CCHMAXPATH];
-  ULONG ulDriveNum, ulDriveMap;
-  
-  /* It's odd to simulate an io-error here, but really this is just
-  ** using the io-error infrastructure to test that SQLite handles this
-  ** function failing. 
-  */
-  SimulateIOError( return SQLITE_IOERR );
-
-  if( sqlite3_temp_directory ) {
-    sqlite3_snprintf(CCHMAXPATH-30, zTempPath, "%s", sqlite3_temp_directory);
-  } else if( DosScanEnv( (PSZ)"TEMP",   &zTempPathCp ) == NO_ERROR ||
-             DosScanEnv( (PSZ)"TMP",    &zTempPathCp ) == NO_ERROR ||
-             DosScanEnv( (PSZ)"TMPDIR", &zTempPathCp ) == NO_ERROR ) {
-    char *zTempPathUTF = convertCpPathToUtf8( (char *)zTempPathCp );
-    sqlite3_snprintf(CCHMAXPATH-30, zTempPath, "%s", zTempPathUTF);
-    free( zTempPathUTF );
-  } else if( DosQueryCurrentDisk( &ulDriveNum, &ulDriveMap ) == NO_ERROR ) {
-    zTempPath[0] = (char)('A' + ulDriveNum - 1);
-    zTempPath[1] = ':'; 
-    zTempPath[2] = '\0'; 
-  } else {
-    zTempPath[0] = '\0'; 
-  }
-  
-  /* Strip off a trailing slashes or backslashes, otherwise we would get *
-   * multiple (back)slashes which causes DosOpen() to fail.              *
-   * Trailing spaces are not allowed, either.                            */
-  j = sqlite3Strlen30(zTempPath);
-  while( j > 0 && ( zTempPath[j-1] == '\\' || zTempPath[j-1] == '/' || 
-                    zTempPath[j-1] == ' ' ) ){
-    j--;
-  }
-  zTempPath[j] = '\0';
-  
-  /* We use 20 bytes to randomize the name */
-  sqlite3_snprintf(nBuf-22, zBuf,
-                   "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath);
-  j = sqlite3Strlen30(zBuf);
-  sqlite3_randomness( 20, &zBuf[j] );
-  for( i = 0; i < 20; i++, j++ ){
-    zBuf[j] = zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
-  }
-  zBuf[j] = 0;
-
-  OSTRACE(( "TEMP FILENAME: %s\n", zBuf ));
-  return SQLITE_OK;
-}
-
-
-/*
-** Turn a relative pathname into a full pathname.  Write the full
-** pathname into zFull[].  zFull[] will be at least pVfs->mxPathname
-** bytes in size.
-*/
-static int os2FullPathname(
-  sqlite3_vfs *pVfs,          /* Pointer to vfs object */
-  const char *zRelative,      /* Possibly relative input path */
-  int nFull,                  /* Size of output buffer in bytes */
-  char *zFull                 /* Output buffer */
-){
-  char *zRelativeCp = convertUtf8PathToCp( zRelative );
-  char zFullCp[CCHMAXPATH] = "\0";
-  char *zFullUTF;
-  APIRET rc = DosQueryPathInfo( (PSZ)zRelativeCp, FIL_QUERYFULLNAME, 
-                                zFullCp, CCHMAXPATH );
-  free( zRelativeCp );
-  zFullUTF = convertCpPathToUtf8( zFullCp );
-  sqlite3_snprintf( nFull, zFull, zFullUTF );
-  free( zFullUTF );
-  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
-}
-
-
-/*
-** Open a file.
-*/
-static int os2Open(
-  sqlite3_vfs *pVfs,            /* Not used */
-  const char *zName,            /* Name of the file (UTF-8) */
-  sqlite3_file *id,             /* Write the SQLite file handle here */
-  int flags,                    /* Open mode flags */
-  int *pOutFlags                /* Status return flags */
-){
-  HFILE h;
-  ULONG ulOpenFlags = 0;
-  ULONG ulOpenMode = 0;
-  ULONG ulAction = 0;
-  ULONG rc;
-  os2File *pFile = (os2File*)id;
-  const char *zUtf8Name = zName;
-  char *zNameCp;
-  char  zTmpname[CCHMAXPATH];
-
-  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
-  int isCreate     = (flags & SQLITE_OPEN_CREATE);
-  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
-#ifndef NDEBUG
-  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
-  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
-  int eType        = (flags & 0xFFFFFF00);
-  int isOpenJournal = (isCreate && (
-        eType==SQLITE_OPEN_MASTER_JOURNAL 
-     || eType==SQLITE_OPEN_MAIN_JOURNAL 
-     || eType==SQLITE_OPEN_WAL
-  ));
-#endif
-
-  UNUSED_PARAMETER(pVfs);
-  assert( id!=0 );
-
-  /* Check the following statements are true: 
-  **
-  **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
-  **   (b) if CREATE is set, then READWRITE must also be set, and
-  **   (c) if EXCLUSIVE is set, then CREATE must also be set.
-  **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
-  */
-  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
-  assert(isCreate==0 || isReadWrite);
-  assert(isExclusive==0 || isCreate);
-  assert(isDelete==0 || isCreate);
-
-  /* The main DB, main journal, WAL file and master journal are never 
-  ** automatically deleted. Nor are they ever temporary files.  */
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
-  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );
-
-  /* Assert that the upper layer has set one of the "file-type" flags. */
-  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
-       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
-       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
-       || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
-  );
-
-  memset( pFile, 0, sizeof(*pFile) );
-  pFile->h = (HFILE)-1;
-
-  /* If the second argument to this function is NULL, generate a 
-  ** temporary file name to use 
-  */
-  if( !zUtf8Name ){
-    assert(isDelete && !isOpenJournal);
-    rc = getTempname(CCHMAXPATH, zTmpname);
-    if( rc!=SQLITE_OK ){
-      return rc;
-    }
-    zUtf8Name = zTmpname;
-  }
-
-  if( isReadWrite ){
-    ulOpenMode |= OPEN_ACCESS_READWRITE;
-  }else{
-    ulOpenMode |= OPEN_ACCESS_READONLY;
-  }
-
-  /* Open in random access mode for possibly better speed.  Allow full
-  ** sharing because file locks will provide exclusive access when needed.
-  ** The handle should not be inherited by child processes and we don't 
-  ** want popups from the critical error handler.
-  */
-  ulOpenMode |= OPEN_FLAGS_RANDOM | OPEN_SHARE_DENYNONE | 
-                OPEN_FLAGS_NOINHERIT | OPEN_FLAGS_FAIL_ON_ERROR;
-
-  /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is 
-  ** created. SQLite doesn't use it to indicate "exclusive access" 
-  ** as it is usually understood.
-  */
-  if( isExclusive ){
-    /* Creates a new file, only if it does not already exist. */
-    /* If the file exists, it fails. */
-    ulOpenFlags |= OPEN_ACTION_CREATE_IF_NEW | OPEN_ACTION_FAIL_IF_EXISTS;
-  }else if( isCreate ){
-    /* Open existing file, or create if it doesn't exist */
-    ulOpenFlags |= OPEN_ACTION_CREATE_IF_NEW | OPEN_ACTION_OPEN_IF_EXISTS;
-  }else{
-    /* Opens a file, only if it exists. */
-    ulOpenFlags |= OPEN_ACTION_FAIL_IF_NEW | OPEN_ACTION_OPEN_IF_EXISTS;
-  }
-
-  zNameCp = convertUtf8PathToCp( zUtf8Name );
-  rc = DosOpen( (PSZ)zNameCp,
-                &h,
-                &ulAction,
-                0L,
-                FILE_NORMAL,
-                ulOpenFlags,
-                ulOpenMode,
-                (PEAOP2)NULL );
-  free( zNameCp );
-
-  if( rc != NO_ERROR ){
-    OSTRACE(( "OPEN Invalid handle rc=%d: zName=%s, ulAction=%#lx, ulFlags=%#lx, ulMode=%#lx\n",
-              rc, zUtf8Name, ulAction, ulOpenFlags, ulOpenMode ));
-
-    if( isReadWrite ){
-      return os2Open( pVfs, zName, id,
-                      ((flags|SQLITE_OPEN_READONLY)&~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
-                      pOutFlags );
-    }else{
-      return SQLITE_CANTOPEN;
-    }
-  }
-
-  if( pOutFlags ){
-    *pOutFlags = isReadWrite ? SQLITE_OPEN_READWRITE : SQLITE_OPEN_READONLY;
-  }
-
-  os2FullPathname( pVfs, zUtf8Name, sizeof( zTmpname ), zTmpname );
-  pFile->zFullPathCp = convertUtf8PathToCp( zTmpname );
-  pFile->pMethod = &os2IoMethod;
-  pFile->flags = flags;
-  pFile->h = h;
-
-  OpenCounter(+1);
-  OSTRACE(( "OPEN %d pOutFlags=%d\n", pFile->h, pOutFlags ));
-  return SQLITE_OK;
-}
-
-/*
-** Delete the named file.
-*/
-static int os2Delete(
-  sqlite3_vfs *pVfs,                     /* Not used on os2 */
-  const char *zFilename,                 /* Name of file to delete */
-  int syncDir                            /* Not used on os2 */
-){
-  APIRET rc;
-  char *zFilenameCp;
-  SimulateIOError( return SQLITE_IOERR_DELETE );
-  zFilenameCp = convertUtf8PathToCp( zFilename );
-  rc = DosDelete( (PSZ)zFilenameCp );
-  free( zFilenameCp );
-  OSTRACE(( "DELETE \"%s\"\n", zFilename ));
-  return (rc == NO_ERROR ||
-          rc == ERROR_FILE_NOT_FOUND ||
-          rc == ERROR_PATH_NOT_FOUND ) ? SQLITE_OK : SQLITE_IOERR_DELETE;
-}
-
-/*
-** Check the existance and status of a file.
-*/
-static int os2Access(
-  sqlite3_vfs *pVfs,        /* Not used on os2 */
-  const char *zFilename,    /* Name of file to check */
-  int flags,                /* Type of test to make on this file */
-  int *pOut                 /* Write results here */
-){
-  APIRET rc;
-  FILESTATUS3 fsts3ConfigInfo;
-  char *zFilenameCp;
-
-  UNUSED_PARAMETER(pVfs);
-  SimulateIOError( return SQLITE_IOERR_ACCESS; );
-  
-  zFilenameCp = convertUtf8PathToCp( zFilename );
-  rc = DosQueryPathInfo( (PSZ)zFilenameCp, FIL_STANDARD,
-                         &fsts3ConfigInfo, sizeof(FILESTATUS3) );
-  free( zFilenameCp );
-  OSTRACE(( "ACCESS fsts3ConfigInfo.attrFile=%d flags=%d rc=%d\n",
-            fsts3ConfigInfo.attrFile, flags, rc ));
-
-  switch( flags ){
-    case SQLITE_ACCESS_EXISTS:
-      /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
-      ** as if it does not exist.
-      */
-      if( fsts3ConfigInfo.cbFile == 0 ) 
-        rc = ERROR_FILE_NOT_FOUND;
-      break;
-    case SQLITE_ACCESS_READ:
-      break;
-    case SQLITE_ACCESS_READWRITE:
-      if( fsts3ConfigInfo.attrFile & FILE_READONLY )
-        rc = ERROR_ACCESS_DENIED;
-      break;
-    default:
-      rc = ERROR_FILE_NOT_FOUND;
-      assert( !"Invalid flags argument" );
-  }
-
-  *pOut = (rc == NO_ERROR);
-  OSTRACE(( "ACCESS %s flags %d: rc=%d\n", zFilename, flags, *pOut ));
-
-  return SQLITE_OK;
-}
-
-
-#ifndef SQLITE_OMIT_LOAD_EXTENSION
-/*
-** Interfaces for opening a shared library, finding entry points
-** within the shared library, and closing the shared library.
-*/
-/*
-** Interfaces for opening a shared library, finding entry points
-** within the shared library, and closing the shared library.
-*/
-static void *os2DlOpen(sqlite3_vfs *pVfs, const char *zFilename){
-  HMODULE hmod;
-  APIRET rc;
-  char *zFilenameCp = convertUtf8PathToCp(zFilename);
-  rc = DosLoadModule(NULL, 0, (PSZ)zFilenameCp, &hmod);
-  free(zFilenameCp);
-  return rc != NO_ERROR ? 0 : (void*)hmod;
-}
-/*
-** A no-op since the error code is returned on the DosLoadModule call.
-** os2Dlopen returns zero if DosLoadModule is not successful.
-*/
-static void os2DlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
-/* no-op */
-}
-static void (*os2DlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol))(void){
-  PFN pfn;
-  APIRET rc;
-  rc = DosQueryProcAddr((HMODULE)pHandle, 0L, (PSZ)zSymbol, &pfn);
-  if( rc != NO_ERROR ){
-    /* if the symbol itself was not found, search again for the same
-     * symbol with an extra underscore, that might be needed depending
-     * on the calling convention */
-    char _zSymbol[256] = "_";
-    strncat(_zSymbol, zSymbol, 254);
-    rc = DosQueryProcAddr((HMODULE)pHandle, 0L, (PSZ)_zSymbol, &pfn);
-  }
-  return rc != NO_ERROR ? 0 : (void(*)(void))pfn;
-}
-static void os2DlClose(sqlite3_vfs *pVfs, void *pHandle){
-  DosFreeModule((HMODULE)pHandle);
-}
-#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
-  #define os2DlOpen 0
-  #define os2DlError 0
-  #define os2DlSym 0
-  #define os2DlClose 0
-#endif
-
-
-/*
-** Write up to nBuf bytes of randomness into zBuf.
-*/
-static int os2Randomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf ){
-  int n = 0;
-#if defined(SQLITE_TEST)
-  n = nBuf;
-  memset(zBuf, 0, nBuf);
-#else
-  int i;                           
-  PPIB ppib;
-  PTIB ptib;
-  DATETIME dt; 
-  static unsigned c = 0;
-  /* Ordered by variation probability */
-  static ULONG svIdx[6] = { QSV_MS_COUNT, QSV_TIME_LOW,
-                            QSV_MAXPRMEM, QSV_MAXSHMEM,
-                            QSV_TOTAVAILMEM, QSV_TOTRESMEM };
-
-  /* 8 bytes; timezone and weekday don't increase the randomness much */
-  if( (int)sizeof(dt)-3 <= nBuf - n ){
-    c += 0x0100;
-    DosGetDateTime(&dt);
-    dt.year = (USHORT)((dt.year - 1900) | c);
-    memcpy(&zBuf[n], &dt, sizeof(dt)-3);
-    n += sizeof(dt)-3;
-  }
-
-  /* 4 bytes; PIDs and TIDs are 16 bit internally, so combine them */
-  if( (int)sizeof(ULONG) <= nBuf - n ){
-    DosGetInfoBlocks(&ptib, &ppib);
-    *(PULONG)&zBuf[n] = MAKELONG(ppib->pib_ulpid,
-                                 ptib->tib_ptib2->tib2_ultid);
-    n += sizeof(ULONG);
-  }
-
-  /* Up to 6 * 4 bytes; variables depend on the system state */
-  for( i = 0; i < 6 && (int)sizeof(ULONG) <= nBuf - n; i++ ){
-    DosQuerySysInfo(svIdx[i], svIdx[i], 
-                    (PULONG)&zBuf[n], sizeof(ULONG));
-    n += sizeof(ULONG);
-  } 
-#endif
-
-  return n;
-}
-
-/*
-** Sleep for a little while.  Return the amount of time slept.
-** The argument is the number of microseconds we want to sleep.
-** The return value is the number of microseconds of sleep actually
-** requested from the underlying operating system, a number which
-** might be greater than or equal to the argument, but not less
-** than the argument.
-*/
-static int os2Sleep( sqlite3_vfs *pVfs, int microsec ){
-  DosSleep( (microsec/1000) );
-  return microsec;
-}
-
-/*
-** The following variable, if set to a non-zero value, becomes the result
-** returned from sqlite3OsCurrentTime().  This is used for testing.
-*/
-#ifdef SQLITE_TEST
-SQLITE_API int sqlite3_current_time = 0;
-#endif
-
-/*
-** Find the current time (in Universal Coordinated Time).  Write into *piNow
-** the current time and date as a Julian Day number times 86_400_000.  In
-** other words, write into *piNow the number of milliseconds since the Julian
-** epoch of noon in Greenwich on November 24, 4714 B.C according to the
-** proleptic Gregorian calendar.
-**
-** On success, return 0.  Return 1 if the time and date cannot be found.
-*/
-static int os2CurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
-#ifdef SQLITE_TEST
-  static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
-#endif
-  int year, month, datepart, timepart;
- 
-  DATETIME dt;
-  DosGetDateTime( &dt );
-
-  year = dt.year;
-  month = dt.month;
-
-  /* Calculations from http://www.astro.keele.ac.uk/~rno/Astronomy/hjd.html
-  ** http://www.astro.keele.ac.uk/~rno/Astronomy/hjd-0.1.c
-  ** Calculate the Julian days
-  */
-  datepart = (int)dt.day - 32076 +
-    1461*(year + 4800 + (month - 14)/12)/4 +
-    367*(month - 2 - (month - 14)/12*12)/12 -
-    3*((year + 4900 + (month - 14)/12)/100)/4;
-
-  /* Time in milliseconds, hours to noon added */
-  timepart = 12*3600*1000 + dt.hundredths*10 + dt.seconds*1000 +
-    ((int)dt.minutes + dt.timezone)*60*1000 + dt.hours*3600*1000;
-
-  *piNow = (sqlite3_int64)datepart*86400*1000 + timepart;
-   
-#ifdef SQLITE_TEST
-  if( sqlite3_current_time ){
-    *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
-  }
-#endif
-
-  UNUSED_PARAMETER(pVfs);
-  return 0;
-}
-
-/*
-** Find the current time (in Universal Coordinated Time).  Write the
-** current time and date as a Julian Day number into *prNow and
-** return 0.  Return 1 if the time and date cannot be found.
-*/
-static int os2CurrentTime( sqlite3_vfs *pVfs, double *prNow ){
-  int rc;
-  sqlite3_int64 i;
-  rc = os2CurrentTimeInt64(pVfs, &i);
-  if( !rc ){
-    *prNow = i/86400000.0;
-  }
-  return rc;
-}
-
-/*
-** The idea is that this function works like a combination of
-** GetLastError() and FormatMessage() on windows (or errno and
-** strerror_r() on unix). After an error is returned by an OS
-** function, SQLite calls this function with zBuf pointing to
-** a buffer of nBuf bytes. The OS layer should populate the
-** buffer with a nul-terminated UTF-8 encoded error message
-** describing the last IO error to have occurred within the calling
-** thread.
-**
-** If the error message is too large for the supplied buffer,
-** it should be truncated. The return value of xGetLastError
-** is zero if the error message fits in the buffer, or non-zero
-** otherwise (if the message was truncated). If non-zero is returned,
-** then it is not necessary to include the nul-terminator character
-** in the output buffer.
-**
-** Not supplying an error message will have no adverse effect
-** on SQLite. It is fine to have an implementation that never
-** returns an error message:
-**
-**   int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-**     assert(zBuf[0]=='\0');
-**     return 0;
-**   }
-**
-** However if an error message is supplied, it will be incorporated
-** by sqlite into the error message available to the user using
-** sqlite3_errmsg(), possibly making IO errors easier to debug.
-*/
-static int os2GetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
-  assert(zBuf[0]=='\0');
-  return 0;
-}
-
-/*
-** Initialize and deinitialize the operating system interface.
-*/
-SQLITE_API int sqlite3_os_init(void){
-  static sqlite3_vfs os2Vfs = {
-    3,                 /* iVersion */
-    sizeof(os2File),   /* szOsFile */
-    CCHMAXPATH,        /* mxPathname */
-    0,                 /* pNext */
-    "os2",             /* zName */
-    0,                 /* pAppData */
-
-    os2Open,           /* xOpen */
-    os2Delete,         /* xDelete */
-    os2Access,         /* xAccess */
-    os2FullPathname,   /* xFullPathname */
-    os2DlOpen,         /* xDlOpen */
-    os2DlError,        /* xDlError */
-    os2DlSym,          /* xDlSym */
-    os2DlClose,        /* xDlClose */
-    os2Randomness,     /* xRandomness */
-    os2Sleep,          /* xSleep */
-    os2CurrentTime,    /* xCurrentTime */
-    os2GetLastError,   /* xGetLastError */
-    os2CurrentTimeInt64, /* xCurrentTimeInt64 */
-    0,                 /* xSetSystemCall */
-    0,                 /* xGetSystemCall */
-    0                  /* xNextSystemCall */
-  };
-  sqlite3_vfs_register(&os2Vfs, 1);
-  initUconvObjects();
-/*  sqlite3OSTrace = 1; */
-  return SQLITE_OK;
-}
-SQLITE_API int sqlite3_os_end(void){
-  freeUconvObjects();
-  return SQLITE_OK;
-}
-
-#endif /* SQLITE_OS_OS2 */
-
-/************** End of os_os2.c **********************************************/
 /************** Begin file os_unix.c *****************************************/
 /*
 ** 2004 May 22
@@ -25039,7 +22967,7 @@ SQLITE_API int sqlite3_os_end(void){
 /* #include <time.h> */
 #include <sys/time.h>
 #include <errno.h>
-#ifndef SQLITE_OMIT_WAL
+#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
 #include <sys/mman.h>
 #endif
 
@@ -25138,6 +23066,15 @@ struct unixFile {
   const char *zPath;                  /* Name of the file */
   unixShm *pShm;                      /* Shared memory segment information */
   int szChunk;                        /* Configured by FCNTL_CHUNK_SIZE */
+  int nFetchOut;                      /* Number of outstanding xFetch refs */
+  sqlite3_int64 mmapSize;             /* Usable size of mapping at pMapRegion */
+  sqlite3_int64 mmapSizeActual;       /* Actual size of mapping at pMapRegion */
+  sqlite3_int64 mmapSizeMax;          /* Configured FCNTL_MMAP_SIZE value */
+  void *pMapRegion;                   /* Memory mapped region */
+#ifdef __QNXNTO__
+  int sectorSize;                     /* Device sector size */
+  int deviceCharacteristics;          /* Precomputed device characteristics */
+#endif
 #if SQLITE_ENABLE_LOCKING_STYLE
   int openFlags;                      /* The flags specified at open() */
 #endif
@@ -25158,7 +23095,9 @@ struct unixFile {
   unsigned char transCntrChng;   /* True if the transaction counter changed */
   unsigned char dbUpdate;        /* True if any part of database file changed */
   unsigned char inNormalWrite;   /* True if in a normal write operation */
+
 #endif
+
 #ifdef SQLITE_TEST
   /* In test mode, increase the size of this structure a bit so that 
   ** it is larger than the struct CrashFile defined in test6.c.
@@ -25182,6 +23121,7 @@ struct unixFile {
 #define UNIXFILE_DELETE      0x20     /* Delete on close */
 #define UNIXFILE_URI         0x40     /* Filename might have query parameters */
 #define UNIXFILE_NOLOCK      0x80     /* Do no file locking */
+#define UNIXFILE_WARNED    0x0100     /* verifyDbFile() warnings have been issued */
 
 /*
 ** Include code that is common to all os_*.c files
@@ -25423,6 +23363,17 @@ SQLITE_API int sqlite3_open_file_count = 0;
 #define threadid 0
 #endif
 
+/*
+** HAVE_MREMAP defaults to true on Linux and false everywhere else.
+*/
+#if !defined(HAVE_MREMAP)
+# if defined(__linux__) && defined(_GNU_SOURCE)
+#  define HAVE_MREMAP 1
+# else
+#  define HAVE_MREMAP 0
+# endif
+#endif
+
 /*
 ** Different Unix systems declare open() in different ways.  Same use
 ** open(const char*,int,mode_t).  Others use open(const char*,int,...).
@@ -25454,7 +23405,7 @@ static int openDirectory(const char*, int*);
 ** to all overrideable system calls.
 */
 static struct unix_syscall {
-  const char *zName;            /* Name of the sytem call */
+  const char *zName;            /* Name of the system call */
   sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
   sqlite3_syscall_ptr pDefault; /* Default value */
 } aSyscall[] = {
@@ -25529,11 +23480,7 @@ static struct unix_syscall {
 #define osPwrite64  ((ssize_t(*)(int,const void*,size_t,off_t))\
                     aSyscall[13].pCurrent)
 
-#if SQLITE_ENABLE_LOCKING_STYLE
   { "fchmod",       (sqlite3_syscall_ptr)fchmod,     0  },
-#else
-  { "fchmod",       (sqlite3_syscall_ptr)0,          0  },
-#endif
 #define osFchmod    ((int(*)(int,mode_t))aSyscall[14].pCurrent)
 
 #if defined(HAVE_POSIX_FALLOCATE) && HAVE_POSIX_FALLOCATE
@@ -25558,8 +23505,18 @@ static struct unix_syscall {
   { "fchown",       (sqlite3_syscall_ptr)posixFchown,     0 },
 #define osFchown    ((int(*)(int,uid_t,gid_t))aSyscall[20].pCurrent)
 
-  { "umask",        (sqlite3_syscall_ptr)umask,           0 },
-#define osUmask     ((mode_t(*)(mode_t))aSyscall[21].pCurrent)
+  { "mmap",       (sqlite3_syscall_ptr)mmap,     0 },
+#define osMmap ((void*(*)(void*,size_t,int,int,int,off_t))aSyscall[21].pCurrent)
+
+  { "munmap",       (sqlite3_syscall_ptr)munmap,          0 },
+#define osMunmap ((void*(*)(void*,size_t))aSyscall[22].pCurrent)
+
+#if HAVE_MREMAP
+  { "mremap",       (sqlite3_syscall_ptr)mremap,          0 },
+#else
+  { "mremap",       (sqlite3_syscall_ptr)0,               0 },
+#endif
+#define osMremap ((void*(*)(void*,size_t,size_t,int,...))aSyscall[23].pCurrent)
 
 }; /* End of the overrideable system calls */
 
@@ -25665,14 +23622,7 @@ static const char *unixNextSystemCall(sqlite3_vfs *p, const char *zName){
 */
 static int robust_open(const char *z, int f, mode_t m){
   int fd;
-  mode_t m2;
-  mode_t origM = 0;
-  if( m==0 ){
-    m2 = SQLITE_DEFAULT_FILE_PERMISSIONS;
-  }else{
-    m2 = m;
-    origM = osUmask(0);
-  }
+  mode_t m2 = m ? m : SQLITE_DEFAULT_FILE_PERMISSIONS;
   do{
 #if defined(O_CLOEXEC)
     fd = osOpen(z,f|O_CLOEXEC,m2);
@@ -25680,12 +23630,20 @@ static int robust_open(const char *z, int f, mode_t m){
     fd = osOpen(z,f,m2);
 #endif
   }while( fd<0 && errno==EINTR );
-  if( m ){
-    osUmask(origM);
-  }
+  if( fd>=0 ){
+    if( m!=0 ){
+      struct stat statbuf;
+      if( osFstat(fd, &statbuf)==0 
+       && statbuf.st_size==0
+       && (statbuf.st_mode&0777)!=m 
+      ){
+        osFchmod(fd, m);
+      }
+    }
 #if defined(FD_CLOEXEC) && (!defined(O_CLOEXEC) || O_CLOEXEC==0)
-  if( fd>=0 ) osFcntl(fd, F_SETFD, osFcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
+    osFcntl(fd, F_SETFD, osFcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
 #endif
+  }
   return fd;
 }
 
@@ -25843,9 +23801,9 @@ static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
   case EACCES: 
     /* EACCES is like EAGAIN during locking operations, but not any other time*/
     if( (sqliteIOErr == SQLITE_IOERR_LOCK) || 
-	(sqliteIOErr == SQLITE_IOERR_UNLOCK) || 
-	(sqliteIOErr == SQLITE_IOERR_RDLOCK) ||
-	(sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) ){
+        (sqliteIOErr == SQLITE_IOERR_UNLOCK) || 
+        (sqliteIOErr == SQLITE_IOERR_RDLOCK) ||
+        (sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) ){
       return SQLITE_BUSY;
     }
     /* else fall through */
@@ -25891,7 +23849,6 @@ static int sqliteErrorFromPosixError(int posixError, int sqliteIOErr) {
 }
 
 
-
 /******************************************************************************
 ****************** Begin Unique File ID Utility Used By VxWorks ***************
 **
@@ -26180,7 +24137,7 @@ static unixInodeInfo *inodeList = 0;
 ** The first argument passed to the macro should be the error code that
 ** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN). 
 ** The two subsequent arguments should be the name of the OS function that
-** failed (e.g. "unlink", "open") and the the associated file-system path,
+** failed (e.g. "unlink", "open") and the associated file-system path,
 ** if any.
 */
 #define unixLogError(a,b,c)     unixLogErrorAtLine(a,b,c,__LINE__)
@@ -26203,7 +24160,7 @@ static int unixLogErrorAtLine(
   zErr = aErr;
 
   /* If STRERROR_R_CHAR_P (set by autoconf scripts) or __USE_GNU is defined,
-  ** assume that the system provides the the GNU version of strerror_r() that 
+  ** assume that the system provides the GNU version of strerror_r() that
   ** returns a pointer to a buffer containing the error message. That pointer 
   ** may point to aErr[], or it may point to some static storage somewhere. 
   ** Otherwise, assume that the system provides the POSIX version of 
@@ -26227,7 +24184,6 @@ static int unixLogErrorAtLine(
   zErr = strerror(iErrno);
 #endif
 
-  assert( errcode!=SQLITE_OK );
   if( zPath==0 ) zPath = "";
   sqlite3_log(errcode,
       "os_unix.c:%d: (%d) %s(%s) - %s",
@@ -26393,6 +24349,50 @@ static int findInodeInfo(
 }
 
 
+/*
+** Check a unixFile that is a database.  Verify the following:
+**
+** (1) There is exactly one hard link on the file
+** (2) The file is not a symbolic link
+** (3) The file has not been renamed or unlinked
+**
+** Issue sqlite3_log(SQLITE_WARNING,...) messages if anything is not right.
+*/
+static void verifyDbFile(unixFile *pFile){
+  struct stat buf;
+  int rc;
+  if( pFile->ctrlFlags & UNIXFILE_WARNED ){
+    /* One or more of the following warnings have already been issued.  Do not
+    ** repeat them so as not to clutter the error log */
+    return;
+  }
+  rc = osFstat(pFile->h, &buf);
+  if( rc!=0 ){
+    sqlite3_log(SQLITE_WARNING, "cannot fstat db file %s", pFile->zPath);
+    pFile->ctrlFlags |= UNIXFILE_WARNED;
+    return;
+  }
+  if( buf.st_nlink==0 && (pFile->ctrlFlags & UNIXFILE_DELETE)==0 ){
+    sqlite3_log(SQLITE_WARNING, "file unlinked while open: %s", pFile->zPath);
+    pFile->ctrlFlags |= UNIXFILE_WARNED;
+    return;
+  }
+  if( buf.st_nlink>1 ){
+    sqlite3_log(SQLITE_WARNING, "multiple links to file: %s", pFile->zPath);
+    pFile->ctrlFlags |= UNIXFILE_WARNED;
+    return;
+  }
+  if( pFile->pInode!=0
+   && ((rc = osStat(pFile->zPath, &buf))!=0
+       || buf.st_ino!=pFile->pInode->fileId.ino)
+  ){
+    sqlite3_log(SQLITE_WARNING, "file renamed while open: %s", pFile->zPath);
+    pFile->ctrlFlags |= UNIXFILE_WARNED;
+    return;
+  }
+}
+
+
 /*
 ** This routine checks if there is a RESERVED lock held on the specified
 ** file by this or any other process. If such a lock is held, set *pResOut
@@ -26892,7 +24892,7 @@ static int posixUnlock(sqlite3_file *id, int eFileLock, int handleNFSUnlock){
         pInode->eFileLock = NO_LOCK;
       }else{
         rc = SQLITE_IOERR_UNLOCK;
-	pFile->lastErrno = errno;
+        pFile->lastErrno = errno;
         pInode->eFileLock = NO_LOCK;
         pFile->eFileLock = NO_LOCK;
       }
@@ -26908,7 +24908,7 @@ static int posixUnlock(sqlite3_file *id, int eFileLock, int handleNFSUnlock){
       closePendingFds(pFile);
     }
   }
-	
+
 end_unlock:
   unixLeaveMutex();
   if( rc==SQLITE_OK ) pFile->eFileLock = eFileLock;
@@ -26923,9 +24923,13 @@ end_unlock:
 ** the requested locking level, this routine is a no-op.
 */
 static int unixUnlock(sqlite3_file *id, int eFileLock){
+  assert( eFileLock==SHARED_LOCK || ((unixFile *)id)->nFetchOut==0 );
   return posixUnlock(id, eFileLock, 0);
 }
 
+static int unixMapfile(unixFile *pFd, i64 nByte);
+static void unixUnmapfile(unixFile *pFd);
+
 /*
 ** This function performs the parts of the "close file" operation 
 ** common to all locking schemes. It closes the directory and file
@@ -26938,6 +24942,7 @@ static int unixUnlock(sqlite3_file *id, int eFileLock){
 */
 static int closeUnixFile(sqlite3_file *id){
   unixFile *pFile = (unixFile*)id;
+  unixUnmapfile(pFile);
   if( pFile->h>=0 ){
     robust_close(pFile, pFile->h, __LINE__);
     pFile->h = -1;
@@ -26964,6 +24969,7 @@ static int closeUnixFile(sqlite3_file *id){
 static int unixClose(sqlite3_file *id){
   int rc = SQLITE_OK;
   unixFile *pFile = (unixFile *)id;
+  verifyDbFile(pFile);
   unixUnlock(id, NO_LOCK);
   unixEnterMutex();
 
@@ -27032,7 +25038,7 @@ static int nolockClose(sqlite3_file *id) {
 /******************************************************************************
 ************************* Begin dot-file Locking ******************************
 **
-** The dotfile locking implementation uses the existance of separate lock
+** The dotfile locking implementation uses the existence of separate lock
 ** files (really a directory) to control access to the database.  This works
 ** on just about every filesystem imaginable.  But there are serious downsides:
 **
@@ -27047,7 +25053,7 @@ static int nolockClose(sqlite3_file *id) {
 **
 ** Dotfile locking works by creating a subdirectory in the same directory as
 ** the database and with the same name but with a ".lock" extension added.
-** The existance of a lock directory implies an EXCLUSIVE lock.  All other
+** The existence of a lock directory implies an EXCLUSIVE lock.  All other
 ** lock types (SHARED, RESERVED, PENDING) are mapped into EXCLUSIVE.
 */
 
@@ -27175,7 +25181,7 @@ static int dotlockUnlock(sqlite3_file *id, int eFileLock) {
 
   assert( pFile );
   OSTRACE(("UNLOCK  %d %d was %d pid=%d (dotlock)\n", pFile->h, eFileLock,
-	   pFile->eFileLock, getpid()));
+           pFile->eFileLock, getpid()));
   assert( eFileLock<=SHARED_LOCK );
   
   /* no-op if possible */
@@ -27214,13 +25220,13 @@ static int dotlockUnlock(sqlite3_file *id, int eFileLock) {
 ** Close a file.  Make sure the lock has been released before closing.
 */
 static int dotlockClose(sqlite3_file *id) {
-  int rc;
+  int rc = SQLITE_OK;
   if( id ){
     unixFile *pFile = (unixFile*)id;
     dotlockUnlock(id, NO_LOCK);
     sqlite3_free(pFile->lockingContext);
+    rc = closeUnixFile(id);
   }
-  rc = closeUnixFile(id);
   return rc;
 }
 /****************** End of the dot-file lock implementation *******************
@@ -27424,10 +25430,12 @@ static int flockUnlock(sqlite3_file *id, int eFileLock) {
 ** Close a file.
 */
 static int flockClose(sqlite3_file *id) {
+  int rc = SQLITE_OK;
   if( id ){
     flockUnlock(id, NO_LOCK);
+    rc = closeUnixFile(id);
   }
-  return closeUnixFile(id);
+  return rc;
 }
 
 #endif /* SQLITE_ENABLE_LOCKING_STYLE && !OS_VXWORK */
@@ -27562,7 +25570,7 @@ static int semUnlock(sqlite3_file *id, int eFileLock) {
   assert( pFile );
   assert( pSem );
   OSTRACE(("UNLOCK  %d %d was %d pid=%d (sem)\n", pFile->h, eFileLock,
-	   pFile->eFileLock, getpid()));
+           pFile->eFileLock, getpid()));
   assert( eFileLock<=SHARED_LOCK );
   
   /* no-op if possible */
@@ -28138,6 +26146,8 @@ static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){
   i64 newOffset;
 #endif
   TIMER_START;
+  assert( cnt==(cnt&0x1ffff) );
+  cnt &= 0x1ffff;
   do{
 #if defined(USE_PREAD)
     got = osPread(id->h, pBuf, cnt, offset);
@@ -28152,7 +26162,7 @@ static int seekAndRead(unixFile *id, sqlite3_int64 offset, void *pBuf, int cnt){
       if( newOffset == -1 ){
         ((unixFile*)id)->lastErrno = errno;
       }else{
-        ((unixFile*)id)->lastErrno = 0;			
+        ((unixFile*)id)->lastErrno = 0;
       }
       return -1;
     }
@@ -28191,6 +26201,8 @@ static int unixRead(
   unixFile *pFile = (unixFile *)id;
   int got;
   assert( id );
+  assert( offset>=0 );
+  assert( amt>0 );
 
   /* If this is a database file (not a journal, master-journal or temp
   ** file), the bytes in the locking range should never be read or written. */
@@ -28201,6 +26213,23 @@ static int unixRead(
   );
 #endif
 
+#if SQLITE_MAX_MMAP_SIZE>0
+  /* Deal with as much of this read request as possible by transfering
+  ** data from the memory mapping using memcpy().  */
+  if( offset<pFile->mmapSize ){
+    if( offset+amt <= pFile->mmapSize ){
+      memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
+      return SQLITE_OK;
+    }else{
+      int nCopy = pFile->mmapSize - offset;
+      memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
+      pBuf = &((u8 *)pBuf)[nCopy];
+      amt -= nCopy;
+      offset += nCopy;
+    }
+  }
+#endif
+
   got = seekAndRead(pFile, offset, pBuf, amt);
   if( got==amt ){
     return SQLITE_OK;
@@ -28215,6 +26244,51 @@ static int unixRead(
   }
 }
 
+/*
+** Attempt to seek the file-descriptor passed as the first argument to
+** absolute offset iOff, then attempt to write nBuf bytes of data from
+** pBuf to it. If an error occurs, return -1 and set *piErrno. Otherwise, 
+** return the actual number of bytes written (which may be less than
+** nBuf).
+*/
+static int seekAndWriteFd(
+  int fd,                         /* File descriptor to write to */
+  i64 iOff,                       /* File offset to begin writing at */
+  const void *pBuf,               /* Copy data from this buffer to the file */
+  int nBuf,                       /* Size of buffer pBuf in bytes */
+  int *piErrno                    /* OUT: Error number if error occurs */
+){
+  int rc = 0;                     /* Value returned by system call */
+
+  assert( nBuf==(nBuf&0x1ffff) );
+  nBuf &= 0x1ffff;
+  TIMER_START;
+
+#if defined(USE_PREAD)
+  do{ rc = osPwrite(fd, pBuf, nBuf, iOff); }while( rc<0 && errno==EINTR );
+#elif defined(USE_PREAD64)
+  do{ rc = osPwrite64(fd, pBuf, nBuf, iOff);}while( rc<0 && errno==EINTR);
+#else
+  do{
+    i64 iSeek = lseek(fd, iOff, SEEK_SET);
+    SimulateIOError( iSeek-- );
+
+    if( iSeek!=iOff ){
+      if( piErrno ) *piErrno = (iSeek==-1 ? errno : 0);
+      return -1;
+    }
+    rc = osWrite(fd, pBuf, nBuf);
+  }while( rc<0 && errno==EINTR );
+#endif
+
+  TIMER_END;
+  OSTRACE(("WRITE   %-3d %5d %7lld %llu\n", fd, rc, iOff, TIMER_ELAPSED));
+
+  if( rc<0 && piErrno ) *piErrno = errno;
+  return rc;
+}
+
+
 /*
 ** Seek to the offset in id->offset then read cnt bytes into pBuf.
 ** Return the number of bytes actually read.  Update the offset.
@@ -28223,37 +26297,7 @@ static int unixRead(
 ** is set before returning.
 */
 static int seekAndWrite(unixFile *id, i64 offset, const void *pBuf, int cnt){
-  int got;
-#if (!defined(USE_PREAD) && !defined(USE_PREAD64))
-  i64 newOffset;
-#endif
-  TIMER_START;
-#if defined(USE_PREAD)
-  do{ got = osPwrite(id->h, pBuf, cnt, offset); }while( got<0 && errno==EINTR );
-#elif defined(USE_PREAD64)
-  do{ got = osPwrite64(id->h, pBuf, cnt, offset);}while( got<0 && errno==EINTR);
-#else
-  do{
-    newOffset = lseek(id->h, offset, SEEK_SET);
-    SimulateIOError( newOffset-- );
-    if( newOffset!=offset ){
-      if( newOffset == -1 ){
-        ((unixFile*)id)->lastErrno = errno;
-      }else{
-        ((unixFile*)id)->lastErrno = 0;			
-      }
-      return -1;
-    }
-    got = osWrite(id->h, pBuf, cnt);
-  }while( got<0 && errno==EINTR );
-#endif
-  TIMER_END;
-  if( got<0 ){
-    ((unixFile*)id)->lastErrno = errno;
-  }
-
-  OSTRACE(("WRITE   %-3d %5d %7lld %llu\n", id->h, got, offset, TIMER_ELAPSED));
-  return got;
+  return seekAndWriteFd(id->h, offset, pBuf, cnt, &id->lastErrno);
 }
 
 
@@ -28303,6 +26347,23 @@ static int unixWrite(
   }
 #endif
 
+#if SQLITE_MAX_MMAP_SIZE>0
+  /* Deal with as much of this write request as possible by transfering
+  ** data from the memory mapping using memcpy().  */
+  if( offset<pFile->mmapSize ){
+    if( offset+amt <= pFile->mmapSize ){
+      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
+      return SQLITE_OK;
+    }else{
+      int nCopy = pFile->mmapSize - offset;
+      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
+      pBuf = &((u8 *)pBuf)[nCopy];
+      amt -= nCopy;
+      offset += nCopy;
+    }
+  }
+#endif
+
   while( amt>0 && (wrote = seekAndWrite(pFile, offset, pBuf, amt))>0 ){
     amt -= wrote;
     offset += wrote;
@@ -28530,7 +26591,7 @@ static int unixSync(sqlite3_file *id, int flags){
   }
 
   /* Also fsync the directory containing the file if the DIRSYNC flag
-  ** is set.  This is a one-time occurrance.  Many systems (examples: AIX)
+  ** is set.  This is a one-time occurrence.  Many systems (examples: AIX)
   ** are unable to fsync a directory, so ignore errors on the fsync.
   */
   if( pFile->ctrlFlags & UNIXFILE_DIRSYNC ){
@@ -28585,6 +26646,14 @@ static int unixTruncate(sqlite3_file *id, i64 nByte){
     }
 #endif
 
+    /* If the file was just truncated to a size smaller than the currently
+    ** mapped region, reduce the effective mapping size as well. SQLite will
+    ** use read() and write() to access data beyond this point from now on.  
+    */
+    if( nByte<pFile->mmapSize ){
+      pFile->mmapSize = nByte;
+    }
+
     return SQLITE_OK;
   }
 }
@@ -28673,6 +26742,19 @@ static int fcntlSizeHint(unixFile *pFile, i64 nByte){
     }
   }
 
+  if( pFile->mmapSizeMax>0 && nByte>pFile->mmapSize ){
+    int rc;
+    if( pFile->szChunk<=0 ){
+      if( robust_ftruncate(pFile->h, nByte) ){
+        pFile->lastErrno = errno;
+        return unixLogError(SQLITE_IOERR_TRUNCATE, "ftruncate", pFile->zPath);
+      }
+    }
+
+    rc = unixMapfile(pFile, nByte);
+    return rc;
+  }
+
   return SQLITE_OK;
 }
 
@@ -28692,6 +26774,9 @@ static void unixModeBit(unixFile *pFile, unsigned char mask, int *pArg){
   }
 }
 
+/* Forward declaration */
+static int unixGetTempname(int nBuf, char *zBuf);
+
 /*
 ** Information and control of an open file handle.
 */
@@ -28729,6 +26814,30 @@ static int unixFileControl(sqlite3_file *id, int op, void *pArg){
       *(char**)pArg = sqlite3_mprintf("%s", pFile->pVfs->zName);
       return SQLITE_OK;
     }
+    case SQLITE_FCNTL_TEMPFILENAME: {
+      char *zTFile = sqlite3_malloc( pFile->pVfs->mxPathname );
+      if( zTFile ){
+        unixGetTempname(pFile->pVfs->mxPathname, zTFile);
+        *(char**)pArg = zTFile;
+      }
+      return SQLITE_OK;
+    }
+    case SQLITE_FCNTL_MMAP_SIZE: {
+      i64 newLimit = *(i64*)pArg;
+      int rc = SQLITE_OK;
+      if( newLimit>sqlite3GlobalConfig.mxMmap ){
+        newLimit = sqlite3GlobalConfig.mxMmap;
+      }
+      *(i64*)pArg = pFile->mmapSizeMax;
+      if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
+        pFile->mmapSizeMax = newLimit;
+        if( pFile->mmapSize>0 ){
+          unixUnmapfile(pFile);
+          rc = unixMapfile(pFile, -1);
+        }
+      }
+      return rc;
+    }
 #ifdef SQLITE_DEBUG
     /* The pager calls this method to signal that it has done
     ** a rollback and that the database is therefore unchanged and
@@ -28760,10 +26869,92 @@ static int unixFileControl(sqlite3_file *id, int op, void *pArg){
 ** a database and its journal file) that the sector size will be the
 ** same for both.
 */
-static int unixSectorSize(sqlite3_file *pFile){
-  (void)pFile;
+#ifndef __QNXNTO__ 
+static int unixSectorSize(sqlite3_file *NotUsed){
+  UNUSED_PARAMETER(NotUsed);
   return SQLITE_DEFAULT_SECTOR_SIZE;
 }
+#endif
+
+/*
+** The following version of unixSectorSize() is optimized for QNX.
+*/
+#ifdef __QNXNTO__
+#include <sys/dcmd_blk.h>
+#include <sys/statvfs.h>
+static int unixSectorSize(sqlite3_file *id){
+  unixFile *pFile = (unixFile*)id;
+  if( pFile->sectorSize == 0 ){
+    struct statvfs fsInfo;
+       
+    /* Set defaults for non-supported filesystems */
+    pFile->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
+    pFile->deviceCharacteristics = 0;
+    if( fstatvfs(pFile->h, &fsInfo) == -1 ) {
+      return pFile->sectorSize;
+    }
+
+    if( !strcmp(fsInfo.f_basetype, "tmp") ) {
+      pFile->sectorSize = fsInfo.f_bsize;
+      pFile->deviceCharacteristics =
+        SQLITE_IOCAP_ATOMIC4K |       /* All ram filesystem writes are atomic */
+        SQLITE_IOCAP_SAFE_APPEND |    /* growing the file does not occur until
+                                      ** the write succeeds */
+        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
+                                      ** so it is ordered */
+        0;
+    }else if( strstr(fsInfo.f_basetype, "etfs") ){
+      pFile->sectorSize = fsInfo.f_bsize;
+      pFile->deviceCharacteristics =
+        /* etfs cluster size writes are atomic */
+        (pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) |
+        SQLITE_IOCAP_SAFE_APPEND |    /* growing the file does not occur until
+                                      ** the write succeeds */
+        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
+                                      ** so it is ordered */
+        0;
+    }else if( !strcmp(fsInfo.f_basetype, "qnx6") ){
+      pFile->sectorSize = fsInfo.f_bsize;
+      pFile->deviceCharacteristics =
+        SQLITE_IOCAP_ATOMIC |         /* All filesystem writes are atomic */
+        SQLITE_IOCAP_SAFE_APPEND |    /* growing the file does not occur until
+                                      ** the write succeeds */
+        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
+                                      ** so it is ordered */
+        0;
+    }else if( !strcmp(fsInfo.f_basetype, "qnx4") ){
+      pFile->sectorSize = fsInfo.f_bsize;
+      pFile->deviceCharacteristics =
+        /* full bitset of atomics from max sector size and smaller */
+        ((pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) << 1) - 2 |
+        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
+                                      ** so it is ordered */
+        0;
+    }else if( strstr(fsInfo.f_basetype, "dos") ){
+      pFile->sectorSize = fsInfo.f_bsize;
+      pFile->deviceCharacteristics =
+        /* full bitset of atomics from max sector size and smaller */
+        ((pFile->sectorSize / 512 * SQLITE_IOCAP_ATOMIC512) << 1) - 2 |
+        SQLITE_IOCAP_SEQUENTIAL |     /* The ram filesystem has no write behind
+                                      ** so it is ordered */
+        0;
+    }else{
+      pFile->deviceCharacteristics =
+        SQLITE_IOCAP_ATOMIC512 |      /* blocks are atomic */
+        SQLITE_IOCAP_SAFE_APPEND |    /* growing the file does not occur until
+                                      ** the write succeeds */
+        0;
+    }
+  }
+  /* Last chance verification.  If the sector size isn't a multiple of 512
+  ** then it isn't valid.*/
+  if( pFile->sectorSize % 512 != 0 ){
+    pFile->deviceCharacteristics = 0;
+    pFile->sectorSize = SQLITE_DEFAULT_SECTOR_SIZE;
+  }
+  return pFile->sectorSize;
+}
+#endif /* __QNXNTO__ */
 
 /*
 ** Return the device characteristics for the file.
@@ -28780,11 +26971,15 @@ static int unixSectorSize(sqlite3_file *pFile){
 */
 static int unixDeviceCharacteristics(sqlite3_file *id){
   unixFile *p = (unixFile*)id;
+  int rc = 0;
+#ifdef __QNXNTO__
+  if( p->sectorSize==0 ) unixSectorSize(id);
+  rc = p->deviceCharacteristics;
+#endif
   if( p->ctrlFlags & UNIXFILE_PSOW ){
-    return SQLITE_IOCAP_POWERSAFE_OVERWRITE;
-  }else{
-    return 0;
+    rc |= SQLITE_IOCAP_POWERSAFE_OVERWRITE;
   }
+  return rc;
 }
 
 #ifndef SQLITE_OMIT_WAL
@@ -28955,7 +27150,7 @@ static void unixShmPurge(unixFile *pFd){
     sqlite3_mutex_free(p->mutex);
     for(i=0; i<p->nRegion; i++){
       if( p->h>=0 ){
-        munmap(p->apRegion[i], p->szRegion);
+        osMunmap(p->apRegion[i], p->szRegion);
       }else{
         sqlite3_free(p->apRegion[i]);
       }
@@ -29195,16 +27390,32 @@ static int unixShmMap(
       if( sStat.st_size<nByte ){
         /* The requested memory region does not exist. If bExtend is set to
         ** false, exit early. *pp will be set to NULL and SQLITE_OK returned.
-        **
-        ** Alternatively, if bExtend is true, use ftruncate() to allocate
-        ** the requested memory region.
         */
-        if( !bExtend ) goto shmpage_out;
-        if( robust_ftruncate(pShmNode->h, nByte) ){
-          rc = unixLogError(SQLITE_IOERR_SHMSIZE, "ftruncate",
-                            pShmNode->zFilename);
+        if( !bExtend ){
           goto shmpage_out;
         }
+
+        /* Alternatively, if bExtend is true, extend the file. Do this by
+        ** writing a single byte to the end of each (OS) page being
+        ** allocated or extended. Technically, we need only write to the
+        ** last page in order to extend the file. But writing to all new
+        ** pages forces the OS to allocate them immediately, which reduces
+        ** the chances of SIGBUS while accessing the mapped region later on.
+        */
+        else{
+          static const int pgsz = 4096;
+          int iPg;
+
+          /* Write to the last byte of each newly allocated or extended page */
+          assert( (nByte % pgsz)==0 );
+          for(iPg=(sStat.st_size/pgsz); iPg<(nByte/pgsz); iPg++){
+            if( seekAndWriteFd(pShmNode->h, iPg*pgsz + pgsz-1, "", 1, 0)!=1 ){
+              const char *zFile = pShmNode->zFilename;
+              rc = unixLogError(SQLITE_IOERR_SHMSIZE, "write", zFile);
+              goto shmpage_out;
+            }
+          }
+        }
       }
     }
 
@@ -29220,9 +27431,9 @@ static int unixShmMap(
     while(pShmNode->nRegion<=iRegion){
       void *pMem;
       if( pShmNode->h>=0 ){
-        pMem = mmap(0, szRegion,
+        pMem = osMmap(0, szRegion,
             pShmNode->isReadonly ? PROT_READ : PROT_READ|PROT_WRITE, 
-            MAP_SHARED, pShmNode->h, pShmNode->nRegion*szRegion
+            MAP_SHARED, pShmNode->h, szRegion*(i64)pShmNode->nRegion
         );
         if( pMem==MAP_FAILED ){
           rc = unixLogError(SQLITE_IOERR_SHMMAP, "mmap", pShmNode->zFilename);
@@ -29437,6 +27648,236 @@ static int unixShmUnmap(
 # define unixShmUnmap   0
 #endif /* #ifndef SQLITE_OMIT_WAL */
 
+/*
+** If it is currently memory mapped, unmap file pFd.
+*/
+static void unixUnmapfile(unixFile *pFd){
+  assert( pFd->nFetchOut==0 );
+#if SQLITE_MAX_MMAP_SIZE>0
+  if( pFd->pMapRegion ){
+    osMunmap(pFd->pMapRegion, pFd->mmapSizeActual);
+    pFd->pMapRegion = 0;
+    pFd->mmapSize = 0;
+    pFd->mmapSizeActual = 0;
+  }
+#endif
+}
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/*
+** Return the system page size.
+*/
+static int unixGetPagesize(void){
+#if HAVE_MREMAP
+  return 512;
+#elif defined(_BSD_SOURCE)
+  return getpagesize();
+#else
+  return (int)sysconf(_SC_PAGESIZE);
+#endif
+}
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
+
+#if SQLITE_MAX_MMAP_SIZE>0
+/*
+** Attempt to set the size of the memory mapping maintained by file 
+** descriptor pFd to nNew bytes. Any existing mapping is discarded.
+**
+** If successful, this function sets the following variables:
+**
+**       unixFile.pMapRegion
+**       unixFile.mmapSize
+**       unixFile.mmapSizeActual
+**
+** If unsuccessful, an error message is logged via sqlite3_log() and
+** the three variables above are zeroed. In this case SQLite should
+** continue accessing the database using the xRead() and xWrite()
+** methods.
+*/
+static void unixRemapfile(
+  unixFile *pFd,                  /* File descriptor object */
+  i64 nNew                        /* Required mapping size */
+){
+  const char *zErr = "mmap";
+  int h = pFd->h;                      /* File descriptor open on db file */
+  u8 *pOrig = (u8 *)pFd->pMapRegion;   /* Pointer to current file mapping */
+  i64 nOrig = pFd->mmapSizeActual;     /* Size of pOrig region in bytes */
+  u8 *pNew = 0;                        /* Location of new mapping */
+  int flags = PROT_READ;               /* Flags to pass to mmap() */
+
+  assert( pFd->nFetchOut==0 );
+  assert( nNew>pFd->mmapSize );
+  assert( nNew<=pFd->mmapSizeMax );
+  assert( nNew>0 );
+  assert( pFd->mmapSizeActual>=pFd->mmapSize );
+  assert( MAP_FAILED!=0 );
+
+  if( (pFd->ctrlFlags & UNIXFILE_RDONLY)==0 ) flags |= PROT_WRITE;
+
+  if( pOrig ){
+    const int szSyspage = unixGetPagesize();
+    i64 nReuse = (pFd->mmapSize & ~(szSyspage-1));
+    u8 *pReq = &pOrig[nReuse];
+
+    /* Unmap any pages of the existing mapping that cannot be reused. */
+    if( nReuse!=nOrig ){
+      osMunmap(pReq, nOrig-nReuse);
+    }
+
+#if HAVE_MREMAP
+    pNew = osMremap(pOrig, nReuse, nNew, MREMAP_MAYMOVE);
+    zErr = "mremap";
+#else
+    pNew = osMmap(pReq, nNew-nReuse, flags, MAP_SHARED, h, nReuse);
+    if( pNew!=MAP_FAILED ){
+      if( pNew!=pReq ){
+        osMunmap(pNew, nNew - nReuse);
+        pNew = 0;
+      }else{
+        pNew = pOrig;
+      }
+    }
+#endif
+
+    /* The attempt to extend the existing mapping failed. Free it. */
+    if( pNew==MAP_FAILED || pNew==0 ){
+      osMunmap(pOrig, nReuse);
+    }
+  }
+
+  /* If pNew is still NULL, try to create an entirely new mapping. */
+  if( pNew==0 ){
+    pNew = osMmap(0, nNew, flags, MAP_SHARED, h, 0);
+  }
+
+  if( pNew==MAP_FAILED ){
+    pNew = 0;
+    nNew = 0;
+    unixLogError(SQLITE_OK, zErr, pFd->zPath);
+
+    /* If the mmap() above failed, assume that all subsequent mmap() calls
+    ** will probably fail too. Fall back to using xRead/xWrite exclusively
+    ** in this case.  */
+    pFd->mmapSizeMax = 0;
+  }
+  pFd->pMapRegion = (void *)pNew;
+  pFd->mmapSize = pFd->mmapSizeActual = nNew;
+}
+#endif
+
+/*
+** Memory map or remap the file opened by file-descriptor pFd (if the file
+** is already mapped, the existing mapping is replaced by the new). Or, if 
+** there already exists a mapping for this file, and there are still 
+** outstanding xFetch() references to it, this function is a no-op.
+**
+** If parameter nByte is non-negative, then it is the requested size of 
+** the mapping to create. Otherwise, if nByte is less than zero, then the 
+** requested size is the size of the file on disk. The actual size of the
+** created mapping is either the requested size or the value configured 
+** using SQLITE_FCNTL_MMAP_LIMIT, whichever is smaller.
+**
+** SQLITE_OK is returned if no error occurs (even if the mapping is not
+** recreated as a result of outstanding references) or an SQLite error
+** code otherwise.
+*/
+static int unixMapfile(unixFile *pFd, i64 nByte){
+#if SQLITE_MAX_MMAP_SIZE>0
+  i64 nMap = nByte;
+  int rc;
+
+  assert( nMap>=0 || pFd->nFetchOut==0 );
+  if( pFd->nFetchOut>0 ) return SQLITE_OK;
+
+  if( nMap<0 ){
+    struct stat statbuf;          /* Low-level file information */
+    rc = osFstat(pFd->h, &statbuf);
+    if( rc!=SQLITE_OK ){
+      return SQLITE_IOERR_FSTAT;
+    }
+    nMap = statbuf.st_size;
+  }
+  if( nMap>pFd->mmapSizeMax ){
+    nMap = pFd->mmapSizeMax;
+  }
+
+  if( nMap!=pFd->mmapSize ){
+    if( nMap>0 ){
+      unixRemapfile(pFd, nMap);
+    }else{
+      unixUnmapfile(pFd);
+    }
+  }
+#endif
+
+  return SQLITE_OK;
+}
+
+/*
+** If possible, return a pointer to a mapping of file fd starting at offset
+** iOff. The mapping must be valid for at least nAmt bytes.
+**
+** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
+** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
+** Finally, if an error does occur, return an SQLite error code. The final
+** value of *pp is undefined in this case.
+**
+** If this function does return a pointer, the caller must eventually 
+** release the reference by calling unixUnfetch().
+*/
+static int unixFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
+#if SQLITE_MAX_MMAP_SIZE>0
+  unixFile *pFd = (unixFile *)fd;   /* The underlying database file */
+#endif
+  *pp = 0;
+
+#if SQLITE_MAX_MMAP_SIZE>0
+  if( pFd->mmapSizeMax>0 ){
+    if( pFd->pMapRegion==0 ){
+      int rc = unixMapfile(pFd, -1);
+      if( rc!=SQLITE_OK ) return rc;
+    }
+    if( pFd->mmapSize >= iOff+nAmt ){
+      *pp = &((u8 *)pFd->pMapRegion)[iOff];
+      pFd->nFetchOut++;
+    }
+  }
+#endif
+  return SQLITE_OK;
+}
+
+/*
+** If the third argument is non-NULL, then this function releases a 
+** reference obtained by an earlier call to unixFetch(). The second
+** argument passed to this function must be the same as the corresponding
+** argument that was passed to the unixFetch() invocation. 
+**
+** Or, if the third argument is NULL, then this function is being called 
+** to inform the VFS layer that, according to POSIX, any existing mapping 
+** may now be invalid and should be unmapped.
+*/
+static int unixUnfetch(sqlite3_file *fd, i64 iOff, void *p){
+  unixFile *pFd = (unixFile *)fd;   /* The underlying database file */
+  UNUSED_PARAMETER(iOff);
+
+  /* If p==0 (unmap the entire file) then there must be no outstanding 
+  ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
+  ** then there must be at least one outstanding.  */
+  assert( (p==0)==(pFd->nFetchOut==0) );
+
+  /* If p!=0, it must match the iOff value. */
+  assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
+
+  if( p ){
+    pFd->nFetchOut--;
+  }else{
+    unixUnmapfile(pFd);
+  }
+
+  assert( pFd->nFetchOut>=0 );
+  return SQLITE_OK;
+}
+
 /*
 ** Here ends the implementation of all sqlite3_file methods.
 **
@@ -29495,7 +27936,9 @@ static const sqlite3_io_methods METHOD = {                                   \
    unixShmMap,                 /* xShmMap */                                 \
    unixShmLock,                /* xShmLock */                                \
    unixShmBarrier,             /* xShmBarrier */                             \
-   unixShmUnmap                /* xShmUnmap */                               \
+   unixShmUnmap,               /* xShmUnmap */                               \
+   unixFetch,                  /* xFetch */                                  \
+   unixUnfetch,                /* xUnfetch */                                \
 };                                                                           \
 static const sqlite3_io_methods *FINDER##Impl(const char *z, unixFile *p){   \
   UNUSED_PARAMETER(z); UNUSED_PARAMETER(p);                                  \
@@ -29512,7 +27955,7 @@ static const sqlite3_io_methods *(*const FINDER)(const char*,unixFile *p)    \
 IOMETHODS(
   posixIoFinder,            /* Finder function name */
   posixIoMethods,           /* sqlite3_io_methods object name */
-  2,                        /* shared memory is enabled */
+  3,                        /* shared memory and mmap are enabled */
   unixClose,                /* xClose method */
   unixLock,                 /* xLock method */
   unixUnlock,               /* xUnlock method */
@@ -29763,11 +28206,12 @@ static int fillInUnixFile(
   pNew->pVfs = pVfs;
   pNew->zPath = zFilename;
   pNew->ctrlFlags = (u8)ctrlFlags;
+  pNew->mmapSizeMax = sqlite3GlobalConfig.szMmap;
   if( sqlite3_uri_boolean(((ctrlFlags & UNIXFILE_URI) ? zFilename : 0),
                            "psow", SQLITE_POWERSAFE_OVERWRITE) ){
     pNew->ctrlFlags |= UNIXFILE_PSOW;
   }
-  if( memcmp(pVfs->zName,"unix-excl",10)==0 ){
+  if( strcmp(pVfs->zName,"unix-excl")==0 ){
     pNew->ctrlFlags |= UNIXFILE_EXCL;
   }
 
@@ -29799,7 +28243,7 @@ static int fillInUnixFile(
     unixEnterMutex();
     rc = findInodeInfo(pNew, &pNew->pInode);
     if( rc!=SQLITE_OK ){
-      /* If an error occured in findInodeInfo(), close the file descriptor
+      /* If an error occurred in findInodeInfo(), close the file descriptor
       ** immediately, before releasing the mutex. findInodeInfo() may fail
       ** in two scenarios:
       **
@@ -29898,15 +28342,15 @@ static int fillInUnixFile(
     if( h>=0 ) robust_close(pNew, h, __LINE__);
     h = -1;
     osUnlink(zFilename);
-    isDelete = 0;
+    pNew->ctrlFlags |= UNIXFILE_DELETE;
   }
-  if( isDelete ) pNew->ctrlFlags |= UNIXFILE_DELETE;
 #endif
   if( rc!=SQLITE_OK ){
     if( h>=0 ) robust_close(pNew, h, __LINE__);
   }else{
     pNew->pMethod = pLockingStyle;
     OpenCounter(+1);
+    verifyDbFile(pNew);
   }
   return rc;
 }
@@ -30406,8 +28850,13 @@ static int unixDelete(
   int rc = SQLITE_OK;
   UNUSED_PARAMETER(NotUsed);
   SimulateIOError(return SQLITE_IOERR_DELETE);
-  if( osUnlink(zPath)==(-1) && errno!=ENOENT ){
-    return unixLogError(SQLITE_IOERR_DELETE, "unlink", zPath);
+  if( osUnlink(zPath)==(-1) ){
+    if( errno==ENOENT ){
+      rc = SQLITE_IOERR_DELETE_NOENT;
+    }else{
+      rc = unixLogError(SQLITE_IOERR_DELETE, "unlink", zPath);
+    }
+    return rc;
   }
 #ifndef SQLITE_DISABLE_DIRSYNC
   if( (dirSync & 1)!=0 ){
@@ -30432,7 +28881,7 @@ static int unixDelete(
 }
 
 /*
-** Test the existance of or access permissions of file zPath. The
+** Test the existence of or access permissions of file zPath. The
 ** test performed depends on the value of flags:
 **
 **     SQLITE_ACCESS_EXISTS: Return 1 if the file exists
@@ -30754,7 +29203,7 @@ static int unixGetLastError(sqlite3_vfs *NotUsed, int NotUsed2, char *NotUsed3){
 ** address in the shared range is taken for a SHARED lock, the entire
 ** shared range is taken for an EXCLUSIVE lock):
 **
-**      PENDING_BYTE        0x40000000		   	
+**      PENDING_BYTE        0x40000000
 **      RESERVED_BYTE       0x40000001
 **      SHARED_RANGE        0x40000002 -> 0x40000200
 **
@@ -31995,7 +30444,7 @@ SQLITE_API int sqlite3_os_init(void){
 
   /* Double-check that the aSyscall[] array has been constructed
   ** correctly.  See ticket [bb3a86e890c8e96ab] */
-  assert( ArraySize(aSyscall)==22 );
+  assert( ArraySize(aSyscall)==24 );
 
   /* Register all VFSes defined in the aVfs[] array */
   for(i=0; i<(sizeof(aVfs)/sizeof(sqlite3_vfs)); i++){
@@ -32037,6 +30486,7 @@ SQLITE_API int sqlite3_os_end(void){
 
 #ifdef __CYGWIN__
 # include <sys/cygwin.h>
+/* # include <errno.h> */
 #endif
 
 /*
@@ -32253,12 +30703,65 @@ SQLITE_API int sqlite3_open_file_count = 0;
 /************** Continuing where we left off in os_win.c *********************/
 
 /*
-** Macro to find the minimum of two numeric values.
+** Compiling and using WAL mode requires several APIs that are only
+** available in Windows platforms based on the NT kernel.
 */
-#ifndef MIN
-# define MIN(x,y) ((x)<(y)?(x):(y))
+#if !SQLITE_OS_WINNT && !defined(SQLITE_OMIT_WAL)
+# error "WAL mode requires support from the Windows NT kernel, compile\
+ with SQLITE_OMIT_WAL."
 #endif
 
+/*
+** Are most of the Win32 ANSI APIs available (i.e. with certain exceptions
+** based on the sub-platform)?
+*/
+#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
+#  define SQLITE_WIN32_HAS_ANSI
+#endif
+
+/*
+** Are most of the Win32 Unicode APIs available (i.e. with certain exceptions
+** based on the sub-platform)?
+*/
+#if SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT
+#  define SQLITE_WIN32_HAS_WIDE
+#endif
+
+/*
+** Do we need to manually define the Win32 file mapping APIs for use with WAL
+** mode (e.g. these APIs are available in the Windows CE SDK; however, they
+** are not present in the header file)?
+*/
+#if SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL)
+/*
+** Two of the file mapping APIs are different under WinRT.  Figure out which
+** set we need.
+*/
+#if SQLITE_OS_WINRT
+WINBASEAPI HANDLE WINAPI CreateFileMappingFromApp(HANDLE, \
+        LPSECURITY_ATTRIBUTES, ULONG, ULONG64, LPCWSTR);
+
+WINBASEAPI LPVOID WINAPI MapViewOfFileFromApp(HANDLE, ULONG, ULONG64, SIZE_T);
+#else
+#if defined(SQLITE_WIN32_HAS_ANSI)
+WINBASEAPI HANDLE WINAPI CreateFileMappingA(HANDLE, LPSECURITY_ATTRIBUTES, \
+        DWORD, DWORD, DWORD, LPCSTR);
+#endif /* defined(SQLITE_WIN32_HAS_ANSI) */
+
+#if defined(SQLITE_WIN32_HAS_WIDE)
+WINBASEAPI HANDLE WINAPI CreateFileMappingW(HANDLE, LPSECURITY_ATTRIBUTES, \
+        DWORD, DWORD, DWORD, LPCWSTR);
+#endif /* defined(SQLITE_WIN32_HAS_WIDE) */
+
+WINBASEAPI LPVOID WINAPI MapViewOfFile(HANDLE, DWORD, DWORD, DWORD, SIZE_T);
+#endif /* SQLITE_OS_WINRT */
+
+/*
+** This file mapping API is common to both Win32 and WinRT.
+*/
+WINBASEAPI BOOL WINAPI UnmapViewOfFile(LPCVOID);
+#endif /* SQLITE_WIN32_FILEMAPPING_API && !defined(SQLITE_OMIT_WAL) */
+
 /*
 ** Some Microsoft compilers lack this definition.
 */
@@ -32274,9 +30777,11 @@ SQLITE_API int sqlite3_open_file_count = 0;
 # define FILE_ATTRIBUTE_MASK     (0x0003FFF7)
 #endif
 
+#ifndef SQLITE_OMIT_WAL
 /* Forward references */
 typedef struct winShm winShm;           /* A connection to shared-memory */
 typedef struct winShmNode winShmNode;   /* A region of shared-memory */
+#endif
 
 /*
 ** WinCE lacks native support for file locking so we have to fake it
@@ -32304,7 +30809,9 @@ struct winFile {
   short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
   u8 ctrlFlags;           /* Flags.  See WINFILE_* below */
   DWORD lastErrno;        /* The Windows errno from the last I/O error */
+#ifndef SQLITE_OMIT_WAL
   winShm *pShm;           /* Instance of shared memory on this file */
+#endif
   const char *zPath;      /* Full pathname of this file */
   int szChunk;            /* Chunk size configured by FCNTL_CHUNK_SIZE */
 #if SQLITE_OS_WINCE
@@ -32314,11 +30821,20 @@ struct winFile {
   winceLock local;        /* Locks obtained by this instance of winFile */
   winceLock *shared;      /* Global shared lock memory for the file  */
 #endif
+#if SQLITE_MAX_MMAP_SIZE>0
+  int nFetchOut;                /* Number of outstanding xFetch references */
+  HANDLE hMap;                  /* Handle for accessing memory mapping */
+  void *pMapRegion;             /* Area memory mapped */
+  sqlite3_int64 mmapSize;       /* Usable size of mapped region */
+  sqlite3_int64 mmapSizeActual; /* Actual size of mapped region */
+  sqlite3_int64 mmapSizeMax;    /* Configured FCNTL_MMAP_SIZE value */
+#endif
 };
 
 /*
 ** Allowed values for winFile.ctrlFlags
 */
+#define WINFILE_RDONLY          0x02   /* Connection is read only */
 #define WINFILE_PERSIST_WAL     0x04   /* Persistent WAL mode */
 #define WINFILE_PSOW            0x10   /* SQLITE_IOCAP_POWERSAFE_OVERWRITE */
 
@@ -32329,6 +30845,22 @@ struct winFile {
 #  define SQLITE_WIN32_DBG_BUF_SIZE   ((int)(4096-sizeof(DWORD)))
 #endif
 
+/*
+ * The value used with sqlite3_win32_set_directory() to specify that
+ * the data directory should be changed.
+ */
+#ifndef SQLITE_WIN32_DATA_DIRECTORY_TYPE
+#  define SQLITE_WIN32_DATA_DIRECTORY_TYPE (1)
+#endif
+
+/*
+ * The value used with sqlite3_win32_set_directory() to specify that
+ * the temporary directory should be changed.
+ */
+#ifndef SQLITE_WIN32_TEMP_DIRECTORY_TYPE
+#  define SQLITE_WIN32_TEMP_DIRECTORY_TYPE (2)
+#endif
+
 /*
  * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
  * various Win32 API heap functions instead of our own.
@@ -32376,6 +30908,7 @@ struct winFile {
 #  define SQLITE_WIN32_HEAP_FLAGS     (0)
 #endif
 
+
 /*
 ** The winMemData structure stores information required by the Win32-specific
 ** sqlite3_mem_methods implementation.
@@ -32437,14 +30970,6 @@ SQLITE_API int sqlite3_os_type = 0;
 static int sqlite3_os_type = 0;
 #endif
 
-#if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
-#  define SQLITE_WIN32_HAS_ANSI
-#endif
-
-#if SQLITE_OS_WINCE || SQLITE_OS_WINNT || SQLITE_OS_WINRT
-#  define SQLITE_WIN32_HAS_WIDE
-#endif
-
 #ifndef SYSCALL
 #  define SYSCALL sqlite3_syscall_ptr
 #endif
@@ -32464,7 +30989,7 @@ static int sqlite3_os_type = 0;
 ** to all overrideable system calls.
 */
 static struct win_syscall {
-  const char *zName;            /* Name of the sytem call */
+  const char *zName;            /* Name of the system call */
   sqlite3_syscall_ptr pCurrent; /* Current value of the system call */
   sqlite3_syscall_ptr pDefault; /* Default value */
 } aSyscall[] = {
@@ -32516,14 +31041,25 @@ static struct win_syscall {
 #define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
         LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)
 
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+#if (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_ANSI) && \
+        !defined(SQLITE_OMIT_WAL))
+  { "CreateFileMappingA",      (SYSCALL)CreateFileMappingA,      0 },
+#else
+  { "CreateFileMappingA",      (SYSCALL)0,                       0 },
+#endif
+
+#define osCreateFileMappingA ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
+        DWORD,DWORD,DWORD,LPCSTR))aSyscall[6].pCurrent)
+
+#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
+        !defined(SQLITE_OMIT_WAL))
   { "CreateFileMappingW",      (SYSCALL)CreateFileMappingW,      0 },
 #else
   { "CreateFileMappingW",      (SYSCALL)0,                       0 },
 #endif
 
 #define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
-        DWORD,DWORD,DWORD,LPCWSTR))aSyscall[6].pCurrent)
+        DWORD,DWORD,DWORD,LPCWSTR))aSyscall[7].pCurrent)
 
 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
   { "CreateMutexW",            (SYSCALL)CreateMutexW,            0 },
@@ -32532,7 +31068,7 @@ static struct win_syscall {
 #endif
 
 #define osCreateMutexW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,BOOL, \
-        LPCWSTR))aSyscall[7].pCurrent)
+        LPCWSTR))aSyscall[8].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_ANSI)
   { "DeleteFileA",             (SYSCALL)DeleteFileA,             0 },
@@ -32540,7 +31076,7 @@ static struct win_syscall {
   { "DeleteFileA",             (SYSCALL)0,                       0 },
 #endif
 
-#define osDeleteFileA ((BOOL(WINAPI*)(LPCSTR))aSyscall[8].pCurrent)
+#define osDeleteFileA ((BOOL(WINAPI*)(LPCSTR))aSyscall[9].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_WIDE)
   { "DeleteFileW",             (SYSCALL)DeleteFileW,             0 },
@@ -32548,7 +31084,7 @@ static struct win_syscall {
   { "DeleteFileW",             (SYSCALL)0,                       0 },
 #endif
 
-#define osDeleteFileW ((BOOL(WINAPI*)(LPCWSTR))aSyscall[9].pCurrent)
+#define osDeleteFileW ((BOOL(WINAPI*)(LPCWSTR))aSyscall[10].pCurrent)
 
 #if SQLITE_OS_WINCE
   { "FileTimeToLocalFileTime", (SYSCALL)FileTimeToLocalFileTime, 0 },
@@ -32557,7 +31093,7 @@ static struct win_syscall {
 #endif
 
 #define osFileTimeToLocalFileTime ((BOOL(WINAPI*)(CONST FILETIME*, \
-        LPFILETIME))aSyscall[10].pCurrent)
+        LPFILETIME))aSyscall[11].pCurrent)
 
 #if SQLITE_OS_WINCE
   { "FileTimeToSystemTime",    (SYSCALL)FileTimeToSystemTime,    0 },
@@ -32566,11 +31102,11 @@ static struct win_syscall {
 #endif
 
 #define osFileTimeToSystemTime ((BOOL(WINAPI*)(CONST FILETIME*, \
-        LPSYSTEMTIME))aSyscall[11].pCurrent)
+        LPSYSTEMTIME))aSyscall[12].pCurrent)
 
   { "FlushFileBuffers",        (SYSCALL)FlushFileBuffers,        0 },
 
-#define osFlushFileBuffers ((BOOL(WINAPI*)(HANDLE))aSyscall[12].pCurrent)
+#define osFlushFileBuffers ((BOOL(WINAPI*)(HANDLE))aSyscall[13].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_ANSI)
   { "FormatMessageA",          (SYSCALL)FormatMessageA,          0 },
@@ -32579,7 +31115,7 @@ static struct win_syscall {
 #endif
 
 #define osFormatMessageA ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPSTR, \
-        DWORD,va_list*))aSyscall[13].pCurrent)
+        DWORD,va_list*))aSyscall[14].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_WIDE)
   { "FormatMessageW",          (SYSCALL)FormatMessageW,          0 },
@@ -32588,15 +31124,19 @@ static struct win_syscall {
 #endif
 
 #define osFormatMessageW ((DWORD(WINAPI*)(DWORD,LPCVOID,DWORD,DWORD,LPWSTR, \
-        DWORD,va_list*))aSyscall[14].pCurrent)
+        DWORD,va_list*))aSyscall[15].pCurrent)
 
+#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
   { "FreeLibrary",             (SYSCALL)FreeLibrary,             0 },
+#else
+  { "FreeLibrary",             (SYSCALL)0,                       0 },
+#endif
 
-#define osFreeLibrary ((BOOL(WINAPI*)(HMODULE))aSyscall[15].pCurrent)
+#define osFreeLibrary ((BOOL(WINAPI*)(HMODULE))aSyscall[16].pCurrent)
 
   { "GetCurrentProcessId",     (SYSCALL)GetCurrentProcessId,     0 },
 
-#define osGetCurrentProcessId ((DWORD(WINAPI*)(VOID))aSyscall[16].pCurrent)
+#define osGetCurrentProcessId ((DWORD(WINAPI*)(VOID))aSyscall[17].pCurrent)
 
 #if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
   { "GetDiskFreeSpaceA",       (SYSCALL)GetDiskFreeSpaceA,       0 },
@@ -32605,7 +31145,7 @@ static struct win_syscall {
 #endif
 
 #define osGetDiskFreeSpaceA ((BOOL(WINAPI*)(LPCSTR,LPDWORD,LPDWORD,LPDWORD, \
-        LPDWORD))aSyscall[17].pCurrent)
+        LPDWORD))aSyscall[18].pCurrent)
 
 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
   { "GetDiskFreeSpaceW",       (SYSCALL)GetDiskFreeSpaceW,       0 },
@@ -32614,7 +31154,7 @@ static struct win_syscall {
 #endif
 
 #define osGetDiskFreeSpaceW ((BOOL(WINAPI*)(LPCWSTR,LPDWORD,LPDWORD,LPDWORD, \
-        LPDWORD))aSyscall[18].pCurrent)
+        LPDWORD))aSyscall[19].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_ANSI)
   { "GetFileAttributesA",      (SYSCALL)GetFileAttributesA,      0 },
@@ -32622,7 +31162,7 @@ static struct win_syscall {
   { "GetFileAttributesA",      (SYSCALL)0,                       0 },
 #endif
 
-#define osGetFileAttributesA ((DWORD(WINAPI*)(LPCSTR))aSyscall[19].pCurrent)
+#define osGetFileAttributesA ((DWORD(WINAPI*)(LPCSTR))aSyscall[20].pCurrent)
 
 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
   { "GetFileAttributesW",      (SYSCALL)GetFileAttributesW,      0 },
@@ -32630,7 +31170,7 @@ static struct win_syscall {
   { "GetFileAttributesW",      (SYSCALL)0,                       0 },
 #endif
 
-#define osGetFileAttributesW ((DWORD(WINAPI*)(LPCWSTR))aSyscall[20].pCurrent)
+#define osGetFileAttributesW ((DWORD(WINAPI*)(LPCWSTR))aSyscall[21].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_WIDE)
   { "GetFileAttributesExW",    (SYSCALL)GetFileAttributesExW,    0 },
@@ -32639,7 +31179,7 @@ static struct win_syscall {
 #endif
 
 #define osGetFileAttributesExW ((BOOL(WINAPI*)(LPCWSTR,GET_FILEEX_INFO_LEVELS, \
-        LPVOID))aSyscall[21].pCurrent)
+        LPVOID))aSyscall[22].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "GetFileSize",             (SYSCALL)GetFileSize,             0 },
@@ -32647,7 +31187,7 @@ static struct win_syscall {
   { "GetFileSize",             (SYSCALL)0,                       0 },
 #endif
 
-#define osGetFileSize ((DWORD(WINAPI*)(HANDLE,LPDWORD))aSyscall[22].pCurrent)
+#define osGetFileSize ((DWORD(WINAPI*)(HANDLE,LPDWORD))aSyscall[23].pCurrent)
 
 #if !SQLITE_OS_WINCE && defined(SQLITE_WIN32_HAS_ANSI)
   { "GetFullPathNameA",        (SYSCALL)GetFullPathNameA,        0 },
@@ -32656,7 +31196,7 @@ static struct win_syscall {
 #endif
 
 #define osGetFullPathNameA ((DWORD(WINAPI*)(LPCSTR,DWORD,LPSTR, \
-        LPSTR*))aSyscall[23].pCurrent)
+        LPSTR*))aSyscall[24].pCurrent)
 
 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
   { "GetFullPathNameW",        (SYSCALL)GetFullPathNameW,        0 },
@@ -32665,12 +31205,13 @@ static struct win_syscall {
 #endif
 
 #define osGetFullPathNameW ((DWORD(WINAPI*)(LPCWSTR,DWORD,LPWSTR, \
-        LPWSTR*))aSyscall[24].pCurrent)
+        LPWSTR*))aSyscall[25].pCurrent)
 
   { "GetLastError",            (SYSCALL)GetLastError,            0 },
 
-#define osGetLastError ((DWORD(WINAPI*)(VOID))aSyscall[25].pCurrent)
+#define osGetLastError ((DWORD(WINAPI*)(VOID))aSyscall[26].pCurrent)
 
+#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
 #if SQLITE_OS_WINCE
   /* The GetProcAddressA() routine is only available on Windows CE. */
   { "GetProcAddressA",         (SYSCALL)GetProcAddressA,         0 },
@@ -32679,9 +31220,12 @@ static struct win_syscall {
   ** an ANSI string regardless of the _UNICODE setting */
   { "GetProcAddressA",         (SYSCALL)GetProcAddress,          0 },
 #endif
+#else
+  { "GetProcAddressA",         (SYSCALL)0,                       0 },
+#endif
 
 #define osGetProcAddressA ((FARPROC(WINAPI*)(HMODULE, \
-        LPCSTR))aSyscall[26].pCurrent)
+        LPCSTR))aSyscall[27].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "GetSystemInfo",           (SYSCALL)GetSystemInfo,           0 },
@@ -32689,11 +31233,11 @@ static struct win_syscall {
   { "GetSystemInfo",           (SYSCALL)0,                       0 },
 #endif
 
-#define osGetSystemInfo ((VOID(WINAPI*)(LPSYSTEM_INFO))aSyscall[27].pCurrent)
+#define osGetSystemInfo ((VOID(WINAPI*)(LPSYSTEM_INFO))aSyscall[28].pCurrent)
 
   { "GetSystemTime",           (SYSCALL)GetSystemTime,           0 },
 
-#define osGetSystemTime ((VOID(WINAPI*)(LPSYSTEMTIME))aSyscall[28].pCurrent)
+#define osGetSystemTime ((VOID(WINAPI*)(LPSYSTEMTIME))aSyscall[29].pCurrent)
 
 #if !SQLITE_OS_WINCE
   { "GetSystemTimeAsFileTime", (SYSCALL)GetSystemTimeAsFileTime, 0 },
@@ -32702,7 +31246,7 @@ static struct win_syscall {
 #endif
 
 #define osGetSystemTimeAsFileTime ((VOID(WINAPI*)( \
-        LPFILETIME))aSyscall[29].pCurrent)
+        LPFILETIME))aSyscall[30].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_ANSI)
   { "GetTempPathA",            (SYSCALL)GetTempPathA,            0 },
@@ -32710,7 +31254,7 @@ static struct win_syscall {
   { "GetTempPathA",            (SYSCALL)0,                       0 },
 #endif
 
-#define osGetTempPathA ((DWORD(WINAPI*)(DWORD,LPSTR))aSyscall[30].pCurrent)
+#define osGetTempPathA ((DWORD(WINAPI*)(DWORD,LPSTR))aSyscall[31].pCurrent)
 
 #if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
   { "GetTempPathW",            (SYSCALL)GetTempPathW,            0 },
@@ -32718,7 +31262,7 @@ static struct win_syscall {
   { "GetTempPathW",            (SYSCALL)0,                       0 },
 #endif
 
-#define osGetTempPathW ((DWORD(WINAPI*)(DWORD,LPWSTR))aSyscall[31].pCurrent)
+#define osGetTempPathW ((DWORD(WINAPI*)(DWORD,LPWSTR))aSyscall[32].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "GetTickCount",            (SYSCALL)GetTickCount,            0 },
@@ -32726,7 +31270,7 @@ static struct win_syscall {
   { "GetTickCount",            (SYSCALL)0,                       0 },
 #endif
 
-#define osGetTickCount ((DWORD(WINAPI*)(VOID))aSyscall[32].pCurrent)
+#define osGetTickCount ((DWORD(WINAPI*)(VOID))aSyscall[33].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_ANSI)
   { "GetVersionExA",           (SYSCALL)GetVersionExA,           0 },
@@ -32735,12 +31279,12 @@ static struct win_syscall {
 #endif
 
 #define osGetVersionExA ((BOOL(WINAPI*)( \
-        LPOSVERSIONINFOA))aSyscall[33].pCurrent)
+        LPOSVERSIONINFOA))aSyscall[34].pCurrent)
 
   { "HeapAlloc",               (SYSCALL)HeapAlloc,               0 },
 
 #define osHeapAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD, \
-        SIZE_T))aSyscall[34].pCurrent)
+        SIZE_T))aSyscall[35].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "HeapCreate",              (SYSCALL)HeapCreate,              0 },
@@ -32749,7 +31293,7 @@ static struct win_syscall {
 #endif
 
 #define osHeapCreate ((HANDLE(WINAPI*)(DWORD,SIZE_T, \
-        SIZE_T))aSyscall[35].pCurrent)
+        SIZE_T))aSyscall[36].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "HeapDestroy",             (SYSCALL)HeapDestroy,             0 },
@@ -32757,21 +31301,21 @@ static struct win_syscall {
   { "HeapDestroy",             (SYSCALL)0,                       0 },
 #endif
 
-#define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[36].pCurrent)
+#define osHeapDestroy ((BOOL(WINAPI*)(HANDLE))aSyscall[37].pCurrent)
 
   { "HeapFree",                (SYSCALL)HeapFree,                0 },
 
-#define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[37].pCurrent)
+#define osHeapFree ((BOOL(WINAPI*)(HANDLE,DWORD,LPVOID))aSyscall[38].pCurrent)
 
   { "HeapReAlloc",             (SYSCALL)HeapReAlloc,             0 },
 
 #define osHeapReAlloc ((LPVOID(WINAPI*)(HANDLE,DWORD,LPVOID, \
-        SIZE_T))aSyscall[38].pCurrent)
+        SIZE_T))aSyscall[39].pCurrent)
 
   { "HeapSize",                (SYSCALL)HeapSize,                0 },
 
 #define osHeapSize ((SIZE_T(WINAPI*)(HANDLE,DWORD, \
-        LPCVOID))aSyscall[39].pCurrent)
+        LPCVOID))aSyscall[40].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "HeapValidate",            (SYSCALL)HeapValidate,            0 },
@@ -32780,23 +31324,24 @@ static struct win_syscall {
 #endif
 
 #define osHeapValidate ((BOOL(WINAPI*)(HANDLE,DWORD, \
-        LPCVOID))aSyscall[40].pCurrent)
+        LPCVOID))aSyscall[41].pCurrent)
 
-#if defined(SQLITE_WIN32_HAS_ANSI)
+#if defined(SQLITE_WIN32_HAS_ANSI) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
   { "LoadLibraryA",            (SYSCALL)LoadLibraryA,            0 },
 #else
   { "LoadLibraryA",            (SYSCALL)0,                       0 },
 #endif
 
-#define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[41].pCurrent)
+#define osLoadLibraryA ((HMODULE(WINAPI*)(LPCSTR))aSyscall[42].pCurrent)
 
-#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)
+#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
+        !defined(SQLITE_OMIT_LOAD_EXTENSION)
   { "LoadLibraryW",            (SYSCALL)LoadLibraryW,            0 },
 #else
   { "LoadLibraryW",            (SYSCALL)0,                       0 },
 #endif
 
-#define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[42].pCurrent)
+#define osLoadLibraryW ((HMODULE(WINAPI*)(LPCWSTR))aSyscall[43].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "LocalFree",               (SYSCALL)LocalFree,               0 },
@@ -32804,7 +31349,7 @@ static struct win_syscall {
   { "LocalFree",               (SYSCALL)0,                       0 },
 #endif
 
-#define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[43].pCurrent)
+#define osLocalFree ((HLOCAL(WINAPI*)(HLOCAL))aSyscall[44].pCurrent)
 
 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
   { "LockFile",                (SYSCALL)LockFile,                0 },
@@ -32814,7 +31359,7 @@ static struct win_syscall {
 
 #ifndef osLockFile
 #define osLockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
-        DWORD))aSyscall[44].pCurrent)
+        DWORD))aSyscall[45].pCurrent)
 #endif
 
 #if !SQLITE_OS_WINCE
@@ -32825,36 +31370,36 @@ static struct win_syscall {
 
 #ifndef osLockFileEx
 #define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
-        LPOVERLAPPED))aSyscall[45].pCurrent)
+        LPOVERLAPPED))aSyscall[46].pCurrent)
 #endif
 
-#if !SQLITE_OS_WINRT
+#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL))
   { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
 #else
   { "MapViewOfFile",           (SYSCALL)0,                       0 },
 #endif
 
 #define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
-        SIZE_T))aSyscall[46].pCurrent)
+        SIZE_T))aSyscall[47].pCurrent)
 
   { "MultiByteToWideChar",     (SYSCALL)MultiByteToWideChar,     0 },
 
 #define osMultiByteToWideChar ((int(WINAPI*)(UINT,DWORD,LPCSTR,int,LPWSTR, \
-        int))aSyscall[47].pCurrent)
+        int))aSyscall[48].pCurrent)
 
   { "QueryPerformanceCounter", (SYSCALL)QueryPerformanceCounter, 0 },
 
 #define osQueryPerformanceCounter ((BOOL(WINAPI*)( \
-        LARGE_INTEGER*))aSyscall[48].pCurrent)
+        LARGE_INTEGER*))aSyscall[49].pCurrent)
 
   { "ReadFile",                (SYSCALL)ReadFile,                0 },
 
 #define osReadFile ((BOOL(WINAPI*)(HANDLE,LPVOID,DWORD,LPDWORD, \
-        LPOVERLAPPED))aSyscall[49].pCurrent)
+        LPOVERLAPPED))aSyscall[50].pCurrent)
 
   { "SetEndOfFile",            (SYSCALL)SetEndOfFile,            0 },
 
-#define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[50].pCurrent)
+#define osSetEndOfFile ((BOOL(WINAPI*)(HANDLE))aSyscall[51].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "SetFilePointer",          (SYSCALL)SetFilePointer,          0 },
@@ -32863,7 +31408,7 @@ static struct win_syscall {
 #endif
 
 #define osSetFilePointer ((DWORD(WINAPI*)(HANDLE,LONG,PLONG, \
-        DWORD))aSyscall[51].pCurrent)
+        DWORD))aSyscall[52].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "Sleep",                   (SYSCALL)Sleep,                   0 },
@@ -32871,12 +31416,12 @@ static struct win_syscall {
   { "Sleep",                   (SYSCALL)0,                       0 },
 #endif
 
-#define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[52].pCurrent)
+#define osSleep ((VOID(WINAPI*)(DWORD))aSyscall[53].pCurrent)
 
   { "SystemTimeToFileTime",    (SYSCALL)SystemTimeToFileTime,    0 },
 
 #define osSystemTimeToFileTime ((BOOL(WINAPI*)(CONST SYSTEMTIME*, \
-        LPFILETIME))aSyscall[53].pCurrent)
+        LPFILETIME))aSyscall[54].pCurrent)
 
 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT
   { "UnlockFile",              (SYSCALL)UnlockFile,              0 },
@@ -32886,7 +31431,7 @@ static struct win_syscall {
 
 #ifndef osUnlockFile
 #define osUnlockFile ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
-        DWORD))aSyscall[54].pCurrent)
+        DWORD))aSyscall[55].pCurrent)
 #endif
 
 #if !SQLITE_OS_WINCE
@@ -32896,21 +31441,25 @@ static struct win_syscall {
 #endif
 
 #define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
-        LPOVERLAPPED))aSyscall[55].pCurrent)
+        LPOVERLAPPED))aSyscall[56].pCurrent)
 
+#if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL)
   { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },
+#else
+  { "UnmapViewOfFile",         (SYSCALL)0,                       0 },
+#endif
 
-#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[56].pCurrent)
+#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[57].pCurrent)
 
   { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },
 
 #define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
-        LPCSTR,LPBOOL))aSyscall[57].pCurrent)
+        LPCSTR,LPBOOL))aSyscall[58].pCurrent)
 
   { "WriteFile",               (SYSCALL)WriteFile,               0 },
 
 #define osWriteFile ((BOOL(WINAPI*)(HANDLE,LPCVOID,DWORD,LPDWORD, \
-        LPOVERLAPPED))aSyscall[58].pCurrent)
+        LPOVERLAPPED))aSyscall[59].pCurrent)
 
 #if SQLITE_OS_WINRT
   { "CreateEventExW",          (SYSCALL)CreateEventExW,          0 },
@@ -32919,7 +31468,7 @@ static struct win_syscall {
 #endif
 
 #define osCreateEventExW ((HANDLE(WINAPI*)(LPSECURITY_ATTRIBUTES,LPCWSTR, \
-        DWORD,DWORD))aSyscall[59].pCurrent)
+        DWORD,DWORD))aSyscall[60].pCurrent)
 
 #if !SQLITE_OS_WINRT
   { "WaitForSingleObject",     (SYSCALL)WaitForSingleObject,     0 },
@@ -32928,25 +31477,25 @@ static struct win_syscall {
 #endif
 
 #define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
-        DWORD))aSyscall[60].pCurrent)
+        DWORD))aSyscall[61].pCurrent)
 
-#if !SQLITE_OS_WINCE
+#if SQLITE_OS_WINRT
   { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
 #else
   { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
 #endif
 
 #define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
-        BOOL))aSyscall[61].pCurrent)
+        BOOL))aSyscall[62].pCurrent)
 
-#if !SQLITE_OS_WINCE
+#if SQLITE_OS_WINRT
   { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
 #else
   { "SetFilePointerEx",        (SYSCALL)0,                       0 },
 #endif
 
 #define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
-        PLARGE_INTEGER,DWORD))aSyscall[62].pCurrent)
+        PLARGE_INTEGER,DWORD))aSyscall[63].pCurrent)
 
 #if SQLITE_OS_WINRT
   { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
@@ -32955,16 +31504,16 @@ static struct win_syscall {
 #endif
 
 #define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
-        FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[63].pCurrent)
+        FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[64].pCurrent)
 
-#if SQLITE_OS_WINRT
+#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
   { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
 #else
   { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
 #endif
 
 #define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
-        SIZE_T))aSyscall[64].pCurrent)
+        SIZE_T))aSyscall[65].pCurrent)
 
 #if SQLITE_OS_WINRT
   { "CreateFile2",             (SYSCALL)CreateFile2,             0 },
@@ -32973,16 +31522,16 @@ static struct win_syscall {
 #endif
 
 #define osCreateFile2 ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD,DWORD, \
-        LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[65].pCurrent)
+        LPCREATEFILE2_EXTENDED_PARAMETERS))aSyscall[66].pCurrent)
 
-#if SQLITE_OS_WINRT
+#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_LOAD_EXTENSION)
   { "LoadPackagedLibrary",     (SYSCALL)LoadPackagedLibrary,     0 },
 #else
   { "LoadPackagedLibrary",     (SYSCALL)0,                       0 },
 #endif
 
 #define osLoadPackagedLibrary ((HMODULE(WINAPI*)(LPCWSTR, \
-        DWORD))aSyscall[66].pCurrent)
+        DWORD))aSyscall[67].pCurrent)
 
 #if SQLITE_OS_WINRT
   { "GetTickCount64",          (SYSCALL)GetTickCount64,          0 },
@@ -32990,7 +31539,7 @@ static struct win_syscall {
   { "GetTickCount64",          (SYSCALL)0,                       0 },
 #endif
 
-#define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[67].pCurrent)
+#define osGetTickCount64 ((ULONGLONG(WINAPI*)(VOID))aSyscall[68].pCurrent)
 
 #if SQLITE_OS_WINRT
   { "GetNativeSystemInfo",     (SYSCALL)GetNativeSystemInfo,     0 },
@@ -32999,7 +31548,7 @@ static struct win_syscall {
 #endif
 
 #define osGetNativeSystemInfo ((VOID(WINAPI*)( \
-        LPSYSTEM_INFO))aSyscall[68].pCurrent)
+        LPSYSTEM_INFO))aSyscall[69].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_ANSI)
   { "OutputDebugStringA",      (SYSCALL)OutputDebugStringA,      0 },
@@ -33007,7 +31556,7 @@ static struct win_syscall {
   { "OutputDebugStringA",      (SYSCALL)0,                       0 },
 #endif
 
-#define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[69].pCurrent)
+#define osOutputDebugStringA ((VOID(WINAPI*)(LPCSTR))aSyscall[70].pCurrent)
 
 #if defined(SQLITE_WIN32_HAS_WIDE)
   { "OutputDebugStringW",      (SYSCALL)OutputDebugStringW,      0 },
@@ -33015,20 +31564,20 @@ static struct win_syscall {
   { "OutputDebugStringW",      (SYSCALL)0,                       0 },
 #endif
 
-#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[70].pCurrent)
+#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[71].pCurrent)
 
   { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },
 
-#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[71].pCurrent)
+#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[72].pCurrent)
 
-#if SQLITE_OS_WINRT
+#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
   { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
 #else
   { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
 #endif
 
 #define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
-        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[72].pCurrent)
+        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[73].pCurrent)
 
 }; /* End of the overrideable system calls */
 
@@ -33120,7 +31669,7 @@ static const char *winNextSystemCall(sqlite3_vfs *p, const char *zName){
 ** (if available).
 */
 
-SQLITE_API void sqlite3_win32_write_debug(char *zBuf, int nBuf){
+SQLITE_API void sqlite3_win32_write_debug(const char *zBuf, int nBuf){
   char zDbgBuf[SQLITE_WIN32_DBG_BUF_SIZE];
   int nMin = MIN(nBuf, (SQLITE_WIN32_DBG_BUF_SIZE - 1)); /* may be negative. */
   if( nMin<-1 ) nMin = -1; /* all negative values become -1. */
@@ -33186,6 +31735,8 @@ SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds){
 */
 #if SQLITE_OS_WINCE || SQLITE_OS_WINRT
 # define isNT()  (1)
+#elif !defined(SQLITE_WIN32_HAS_WIDE)
+# define isNT()  (0)
 #else
   static int isNT(void){
     if( sqlite3_os_type==0 ){
@@ -33196,7 +31747,7 @@ SQLITE_API void sqlite3_win32_sleep(DWORD milliseconds){
     }
     return sqlite3_os_type==2;
   }
-#endif /* SQLITE_OS_WINCE */
+#endif
 
 #ifdef SQLITE_WIN32_MALLOC
 /*
@@ -33406,7 +31957,7 @@ static LPWSTR utf8ToUnicode(const char *zFilename){
   if( nChar==0 ){
     return 0;
   }
-  zWideFilename = sqlite3_malloc( nChar*sizeof(zWideFilename[0]) );
+  zWideFilename = sqlite3MallocZero( nChar*sizeof(zWideFilename[0]) );
   if( zWideFilename==0 ){
     return 0;
   }
@@ -33431,7 +31982,7 @@ static char *unicodeToUtf8(LPCWSTR zWideFilename){
   if( nByte == 0 ){
     return 0;
   }
-  zFilename = sqlite3_malloc( nByte );
+  zFilename = sqlite3MallocZero( nByte );
   if( zFilename==0 ){
     return 0;
   }
@@ -33461,7 +32012,7 @@ static LPWSTR mbcsToUnicode(const char *zFilename){
   if( nByte==0 ){
     return 0;
   }
-  zMbcsFilename = sqlite3_malloc( nByte*sizeof(zMbcsFilename[0]) );
+  zMbcsFilename = sqlite3MallocZero( nByte*sizeof(zMbcsFilename[0]) );
   if( zMbcsFilename==0 ){
     return 0;
   }
@@ -33490,7 +32041,7 @@ static char *unicodeToMbcs(LPCWSTR zWideFilename){
   if( nByte == 0 ){
     return 0;
   }
-  zFilename = sqlite3_malloc( nByte );
+  zFilename = sqlite3MallocZero( nByte );
   if( zFilename==0 ){
     return 0;
   }
@@ -33537,6 +32088,42 @@ SQLITE_API char *sqlite3_win32_utf8_to_mbcs(const char *zFilename){
   return zFilenameMbcs;
 }
 
+/*
+** This function sets the data directory or the temporary directory based on
+** the provided arguments.  The type argument must be 1 in order to set the
+** data directory or 2 in order to set the temporary directory.  The zValue
+** argument is the name of the directory to use.  The return value will be
+** SQLITE_OK if successful.
+*/
+SQLITE_API int sqlite3_win32_set_directory(DWORD type, LPCWSTR zValue){
+  char **ppDirectory = 0;
+#ifndef SQLITE_OMIT_AUTOINIT
+  int rc = sqlite3_initialize();
+  if( rc ) return rc;
+#endif
+  if( type==SQLITE_WIN32_DATA_DIRECTORY_TYPE ){
+    ppDirectory = &sqlite3_data_directory;
+  }else if( type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE ){
+    ppDirectory = &sqlite3_temp_directory;
+  }
+  assert( !ppDirectory || type==SQLITE_WIN32_DATA_DIRECTORY_TYPE
+          || type==SQLITE_WIN32_TEMP_DIRECTORY_TYPE
+  );
+  assert( !ppDirectory || sqlite3MemdebugHasType(*ppDirectory, MEMTYPE_HEAP) );
+  if( ppDirectory ){
+    char *zValueUtf8 = 0;
+    if( zValue && zValue[0] ){
+      zValueUtf8 = unicodeToUtf8(zValue);
+      if ( zValueUtf8==0 ){
+        return SQLITE_NOMEM;
+      }
+    }
+    sqlite3_free(*ppDirectory);
+    *ppDirectory = zValueUtf8;
+    return SQLITE_OK;
+  }
+  return SQLITE_ERROR;
+}
 
 /*
 ** The return value of getLastErrorMsg
@@ -33608,7 +32195,7 @@ static int getLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
   }
 #endif
   if( 0 == dwLen ){
-    sqlite3_snprintf(nBuf, zBuf, "OsError 0x%x (%u)", lastErrno, lastErrno);
+    sqlite3_snprintf(nBuf, zBuf, "OsError 0x%lx (%lu)", lastErrno, lastErrno);
   }else{
     /* copy a maximum of nBuf chars to output buffer */
     sqlite3_snprintf(nBuf, zBuf, "%s", zOut);
@@ -33631,7 +32218,7 @@ static int getLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){
 ** The first argument passed to the macro should be the error code that
 ** will be returned to SQLite (e.g. SQLITE_IOERR_DELETE, SQLITE_CANTOPEN). 
 ** The two subsequent arguments should be the name of the OS function that
-** failed and the the associated file-system path, if any.
+** failed and the associated file-system path, if any.
 */
 #define winLogError(a,b,c,d)   winLogErrorAtLine(a,b,c,d,__LINE__)
 static int winLogErrorAtLine(
@@ -33651,7 +32238,7 @@ static int winLogErrorAtLine(
   for(i=0; zMsg[i] && zMsg[i]!='\r' && zMsg[i]!='\n'; i++){}
   zMsg[i] = 0;
   sqlite3_log(errcode,
-      "os_win.c:%d: (%d) %s(%s) - %s",
+      "os_win.c:%d: (%lu) %s(%s) - %s",
       iLine, lastErrno, zFunc, zPath, zMsg
   );
 
@@ -33715,9 +32302,10 @@ static void logIoerr(int nRetry){
 /*************************************************************************
 ** This section contains code for WinCE only.
 */
+#if !defined(SQLITE_MSVC_LOCALTIME_API) || !SQLITE_MSVC_LOCALTIME_API
 /*
-** Windows CE does not have a localtime() function.  So create a
-** substitute.
+** The MSVC CRT on Windows CE may not have a localtime() function.  So
+** create a substitute.
 */
 /* #include <time.h> */
 struct tm *__cdecl localtime(const time_t *t)
@@ -33741,6 +32329,7 @@ struct tm *__cdecl localtime(const time_t *t)
   y.tm_sec = pTm.wSecond;
   return &y;
 }
+#endif
 
 #define HANDLE_TO_WINFILE(a) (winFile*)&((char*)a)[-(int)offsetof(winFile,h)]
 
@@ -33762,15 +32351,17 @@ static void winceMutexAcquire(HANDLE h){
 ** Create the mutex and shared memory used for locking in the file
 ** descriptor pFile
 */
-static BOOL winceCreateLock(const char *zFilename, winFile *pFile){
+static int winceCreateLock(const char *zFilename, winFile *pFile){
   LPWSTR zTok;
   LPWSTR zName;
+  DWORD lastErrno;
+  BOOL bLogged = FALSE;
   BOOL bInit = TRUE;
 
   zName = utf8ToUnicode(zFilename);
   if( zName==0 ){
     /* out of memory */
-    return FALSE;
+    return SQLITE_IOERR_NOMEM;
   }
 
   /* Initialize the local lockdata */
@@ -33787,9 +32378,10 @@ static BOOL winceCreateLock(const char *zFilename, winFile *pFile){
   pFile->hMutex = osCreateMutexW(NULL, FALSE, zName);
   if (!pFile->hMutex){
     pFile->lastErrno = osGetLastError();
-    winLogError(SQLITE_ERROR, pFile->lastErrno, "winceCreateLock1", zFilename);
+    winLogError(SQLITE_IOERR, pFile->lastErrno,
+                "winceCreateLock1", zFilename);
     sqlite3_free(zName);
-    return FALSE;
+    return SQLITE_IOERR;
   }
 
   /* Acquire the mutex before continuing */
@@ -33806,41 +32398,49 @@ static BOOL winceCreateLock(const char *zFilename, winFile *pFile){
 
   /* Set a flag that indicates we're the first to create the memory so it 
   ** must be zero-initialized */
-  if (osGetLastError() == ERROR_ALREADY_EXISTS){
+  lastErrno = osGetLastError();
+  if (lastErrno == ERROR_ALREADY_EXISTS){
     bInit = FALSE;
   }
 
   sqlite3_free(zName);
 
   /* If we succeeded in making the shared memory handle, map it. */
-  if (pFile->hShared){
+  if( pFile->hShared ){
     pFile->shared = (winceLock*)osMapViewOfFile(pFile->hShared, 
              FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
     /* If mapping failed, close the shared memory handle and erase it */
-    if (!pFile->shared){
+    if( !pFile->shared ){
       pFile->lastErrno = osGetLastError();
-      winLogError(SQLITE_ERROR, pFile->lastErrno,
-               "winceCreateLock2", zFilename);
+      winLogError(SQLITE_IOERR, pFile->lastErrno,
+                  "winceCreateLock2", zFilename);
+      bLogged = TRUE;
       osCloseHandle(pFile->hShared);
       pFile->hShared = NULL;
     }
   }
 
   /* If shared memory could not be created, then close the mutex and fail */
-  if (pFile->hShared == NULL){
+  if( pFile->hShared==NULL ){
+    if( !bLogged ){
+      pFile->lastErrno = lastErrno;
+      winLogError(SQLITE_IOERR, pFile->lastErrno,
+                  "winceCreateLock3", zFilename);
+      bLogged = TRUE;
+    }
     winceMutexRelease(pFile->hMutex);
     osCloseHandle(pFile->hMutex);
     pFile->hMutex = NULL;
-    return FALSE;
+    return SQLITE_IOERR;
   }
   
   /* Initialize the shared memory if we're supposed to */
-  if (bInit) {
+  if( bInit ){
     memset(pFile->shared, 0, sizeof(winceLock));
   }
 
   winceMutexRelease(pFile->hMutex);
-  return TRUE;
+  return SQLITE_OK;
 }
 
 /*
@@ -33919,7 +32519,8 @@ static BOOL winceLockFile(
   }
 
   /* Want a pending lock? */
-  else if (dwFileOffsetLow == (DWORD)PENDING_BYTE && nNumberOfBytesToLockLow == 1){
+  else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
+           && nNumberOfBytesToLockLow == 1){
     /* If no pending lock has been acquired, then acquire it */
     if (pFile->shared->bPending == 0) {
       pFile->shared->bPending = TRUE;
@@ -33929,7 +32530,8 @@ static BOOL winceLockFile(
   }
 
   /* Want a reserved lock? */
-  else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE && nNumberOfBytesToLockLow == 1){
+  else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
+           && nNumberOfBytesToLockLow == 1){
     if (pFile->shared->bReserved == 0) {
       pFile->shared->bReserved = TRUE;
       pFile->local.bReserved = TRUE;
@@ -33972,7 +32574,8 @@ static BOOL winceUnlockFile(
 
     /* Did we just have a reader lock? */
     else if (pFile->local.nReaders){
-      assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE || nNumberOfBytesToUnlockLow == 1);
+      assert(nNumberOfBytesToUnlockLow == (DWORD)SHARED_SIZE
+             || nNumberOfBytesToUnlockLow == 1);
       pFile->local.nReaders --;
       if (pFile->local.nReaders == 0)
       {
@@ -33983,7 +32586,8 @@ static BOOL winceUnlockFile(
   }
 
   /* Releasing a pending lock */
-  else if (dwFileOffsetLow == (DWORD)PENDING_BYTE && nNumberOfBytesToUnlockLow == 1){
+  else if (dwFileOffsetLow == (DWORD)PENDING_BYTE
+           && nNumberOfBytesToUnlockLow == 1){
     if (pFile->local.bPending){
       pFile->local.bPending = FALSE;
       pFile->shared->bPending = FALSE;
@@ -33991,7 +32595,8 @@ static BOOL winceUnlockFile(
     }
   }
   /* Releasing a reserved lock */
-  else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE && nNumberOfBytesToUnlockLow == 1){
+  else if (dwFileOffsetLow == (DWORD)RESERVED_BYTE
+           && nNumberOfBytesToUnlockLow == 1){
     if (pFile->local.bReserved) {
       pFile->local.bReserved = FALSE;
       pFile->shared->bReserved = FALSE;
@@ -34094,6 +32699,8 @@ static int seekWinFile(winFile *pFile, sqlite3_int64 iOffset){
   DWORD dwRet;                    /* Value returned by SetFilePointer() */
   DWORD lastErrno;                /* Value returned by GetLastError() */
 
+  OSTRACE(("SEEK file=%p, offset=%lld\n", pFile->h, iOffset));
+
   upperBits = (LONG)((iOffset>>32) & 0x7fffffff);
   lowerBits = (LONG)(iOffset & 0xffffffff);
 
@@ -34101,7 +32708,7 @@ static int seekWinFile(winFile *pFile, sqlite3_int64 iOffset){
   ** containing the lower 32-bits of the new file-offset. Or, if it fails,
   ** it returns INVALID_SET_FILE_POINTER. However according to MSDN, 
   ** INVALID_SET_FILE_POINTER may also be a valid new offset. So to determine 
-  ** whether an error has actually occured, it is also necessary to call 
+  ** whether an error has actually occurred, it is also necessary to call 
   ** GetLastError().
   */
   dwRet = osSetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
@@ -34111,9 +32718,11 @@ static int seekWinFile(winFile *pFile, sqlite3_int64 iOffset){
     pFile->lastErrno = lastErrno;
     winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
              "seekWinFile", pFile->zPath);
+    OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
     return 1;
   }
 
+  OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
   return 0;
 #else
   /*
@@ -34130,13 +32739,20 @@ static int seekWinFile(winFile *pFile, sqlite3_int64 iOffset){
     pFile->lastErrno = osGetLastError();
     winLogError(SQLITE_IOERR_SEEK, pFile->lastErrno,
              "seekWinFile", pFile->zPath);
+    OSTRACE(("SEEK file=%p, rc=SQLITE_IOERR_SEEK\n", pFile->h));
     return 1;
   }
 
+  OSTRACE(("SEEK file=%p, rc=SQLITE_OK\n", pFile->h));
   return 0;
 #endif
 }
 
+#if SQLITE_MAX_MMAP_SIZE>0
+/* Forward references to VFS methods */
+static int winUnmapfile(winFile*);
+#endif
+
 /*
 ** Close a file.
 **
@@ -34153,8 +32769,17 @@ static int winClose(sqlite3_file *id){
   winFile *pFile = (winFile*)id;
 
   assert( id!=0 );
+#ifndef SQLITE_OMIT_WAL
   assert( pFile->pShm==0 );
-  OSTRACE(("CLOSE %d\n", pFile->h));
+#endif
+  assert( pFile->h!=NULL && pFile->h!=INVALID_HANDLE_VALUE );
+  OSTRACE(("CLOSE file=%p\n", pFile->h));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+  rc = winUnmapfile(pFile);
+  if( rc!=SQLITE_OK ) return rc;
+#endif
+
   do{
     rc = osCloseHandle(pFile->h);
     /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
@@ -34174,11 +32799,11 @@ static int winClose(sqlite3_file *id){
     sqlite3_free(pFile->zDeleteOnClose);
   }
 #endif
-  OSTRACE(("CLOSE %d %s\n", pFile->h, rc ? "ok" : "failed"));
   if( rc ){
     pFile->h = NULL;
   }
   OpenCounter(-1);
+  OSTRACE(("CLOSE file=%p, rc=%s\n", pFile->h, rc ? "ok" : "failed"));
   return rc ? SQLITE_OK
             : winLogError(SQLITE_IOERR_CLOSE, osGetLastError(),
                           "winClose", pFile->zPath);
@@ -34203,11 +32828,33 @@ static int winRead(
   int nRetry = 0;                 /* Number of retrys */
 
   assert( id!=0 );
+  assert( amt>0 );
+  assert( offset>=0 );
   SimulateIOError(return SQLITE_IOERR_READ);
-  OSTRACE(("READ %d lock=%d\n", pFile->h, pFile->locktype));
+  OSTRACE(("READ file=%p, buffer=%p, amount=%d, offset=%lld, lock=%d\n",
+           pFile->h, pBuf, amt, offset, pFile->locktype));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+  /* Deal with as much of this read request as possible by transfering
+  ** data from the memory mapping using memcpy().  */
+  if( offset<pFile->mmapSize ){
+    if( offset+amt <= pFile->mmapSize ){
+      memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], amt);
+      OSTRACE(("READ-MMAP file=%p, rc=SQLITE_OK\n", pFile->h));
+      return SQLITE_OK;
+    }else{
+      int nCopy = (int)(pFile->mmapSize - offset);
+      memcpy(pBuf, &((u8 *)(pFile->pMapRegion))[offset], nCopy);
+      pBuf = &((u8 *)pBuf)[nCopy];
+      amt -= nCopy;
+      offset += nCopy;
+    }
+  }
+#endif
 
 #if SQLITE_OS_WINCE
   if( seekWinFile(pFile, offset) ){
+    OSTRACE(("READ file=%p, rc=SQLITE_FULL\n", pFile->h));
     return SQLITE_FULL;
   }
   while( !osReadFile(pFile->h, pBuf, amt, &nRead, 0) ){
@@ -34221,6 +32868,7 @@ static int winRead(
     DWORD lastErrno;
     if( retryIoerr(&nRetry, &lastErrno) ) continue;
     pFile->lastErrno = lastErrno;
+    OSTRACE(("READ file=%p, rc=SQLITE_IOERR_READ\n", pFile->h));
     return winLogError(SQLITE_IOERR_READ, pFile->lastErrno,
              "winRead", pFile->zPath);
   }
@@ -34228,9 +32876,11 @@ static int winRead(
   if( nRead<(DWORD)amt ){
     /* Unread parts of the buffer must be zero-filled */
     memset(&((char*)pBuf)[nRead], 0, amt-nRead);
+    OSTRACE(("READ file=%p, rc=SQLITE_IOERR_SHORT_READ\n", pFile->h));
     return SQLITE_IOERR_SHORT_READ;
   }
 
+  OSTRACE(("READ file=%p, rc=SQLITE_OK\n", pFile->h));
   return SQLITE_OK;
 }
 
@@ -34244,7 +32894,7 @@ static int winWrite(
   int amt,                        /* Number of bytes to write */
   sqlite3_int64 offset            /* Offset into the file to begin writing at */
 ){
-  int rc = 0;                     /* True if error has occured, else false */
+  int rc = 0;                     /* True if error has occurred, else false */
   winFile *pFile = (winFile*)id;  /* File handle */
   int nRetry = 0;                 /* Number of retries */
 
@@ -34253,7 +32903,26 @@ static int winWrite(
   SimulateIOError(return SQLITE_IOERR_WRITE);
   SimulateDiskfullError(return SQLITE_FULL);
 
-  OSTRACE(("WRITE %d lock=%d\n", pFile->h, pFile->locktype));
+  OSTRACE(("WRITE file=%p, buffer=%p, amount=%d, offset=%lld, lock=%d\n",
+           pFile->h, pBuf, amt, offset, pFile->locktype));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+  /* Deal with as much of this write request as possible by transfering
+  ** data from the memory mapping using memcpy().  */
+  if( offset<pFile->mmapSize ){
+    if( offset+amt <= pFile->mmapSize ){
+      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, amt);
+      OSTRACE(("WRITE-MMAP file=%p, rc=SQLITE_OK\n", pFile->h));
+      return SQLITE_OK;
+    }else{
+      int nCopy = (int)(pFile->mmapSize - offset);
+      memcpy(&((u8 *)(pFile->pMapRegion))[offset], pBuf, nCopy);
+      pBuf = &((u8 *)pBuf)[nCopy];
+      amt -= nCopy;
+      offset += nCopy;
+    }
+  }
+#endif
 
 #if SQLITE_OS_WINCE
   rc = seekWinFile(pFile, offset);
@@ -34284,7 +32953,8 @@ static int winWrite(
         if( retryIoerr(&nRetry, &lastErrno) ) continue;
         break;
       }
-      if( nWrite<=0 ){
+      assert( nWrite==0 || nWrite<=(DWORD)nRem );
+      if( nWrite==0 || nWrite>(DWORD)nRem ){
         lastErrno = osGetLastError();
         break;
       }
@@ -34305,13 +32975,16 @@ static int winWrite(
   if( rc ){
     if(   ( pFile->lastErrno==ERROR_HANDLE_DISK_FULL )
        || ( pFile->lastErrno==ERROR_DISK_FULL )){
+      OSTRACE(("WRITE file=%p, rc=SQLITE_FULL\n", pFile->h));
       return SQLITE_FULL;
     }
+    OSTRACE(("WRITE file=%p, rc=SQLITE_IOERR_WRITE\n", pFile->h));
     return winLogError(SQLITE_IOERR_WRITE, pFile->lastErrno,
              "winWrite", pFile->zPath);
   }else{
     logIoerr(nRetry);
   }
+  OSTRACE(("WRITE file=%p, rc=SQLITE_OK\n", pFile->h));
   return SQLITE_OK;
 }
 
@@ -34321,11 +32994,12 @@ static int winWrite(
 static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
   winFile *pFile = (winFile*)id;  /* File handle object */
   int rc = SQLITE_OK;             /* Return code for this function */
+  DWORD lastErrno;
 
   assert( pFile );
-
-  OSTRACE(("TRUNCATE %d %lld\n", pFile->h, nByte));
   SimulateIOError(return SQLITE_IOERR_TRUNCATE);
+  OSTRACE(("TRUNCATE file=%p, size=%lld, lock=%d\n",
+           pFile->h, nByte, pFile->locktype));
 
   /* If the user has configured a chunk-size for this file, truncate the
   ** file so that it consists of an integer number of chunks (i.e. the
@@ -34339,14 +33013,25 @@ static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
   /* SetEndOfFile() returns non-zero when successful, or zero when it fails. */
   if( seekWinFile(pFile, nByte) ){
     rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
-             "winTruncate1", pFile->zPath);
-  }else if( 0==osSetEndOfFile(pFile->h) ){
-    pFile->lastErrno = osGetLastError();
+                     "winTruncate1", pFile->zPath);
+  }else if( 0==osSetEndOfFile(pFile->h) &&
+            ((lastErrno = osGetLastError())!=ERROR_USER_MAPPED_FILE) ){
+    pFile->lastErrno = lastErrno;
     rc = winLogError(SQLITE_IOERR_TRUNCATE, pFile->lastErrno,
-             "winTruncate2", pFile->zPath);
+                     "winTruncate2", pFile->zPath);
   }
 
-  OSTRACE(("TRUNCATE %d %lld %s\n", pFile->h, nByte, rc ? "failed" : "ok"));
+#if SQLITE_MAX_MMAP_SIZE>0
+  /* If the file was truncated to a size smaller than the currently
+  ** mapped region, reduce the effective mapping size as well. SQLite will
+  ** use read() and write() to access data beyond this point from now on.
+  */
+  if( pFile->pMapRegion && nByte<pFile->mmapSize ){
+    pFile->mmapSize = nByte;
+  }
+#endif
+
+  OSTRACE(("TRUNCATE file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
   return rc;
 }
 
@@ -34386,13 +33071,14 @@ static int winSync(sqlite3_file *id, int flags){
       || (flags&0x0F)==SQLITE_SYNC_FULL
   );
 
-  OSTRACE(("SYNC %d lock=%d\n", pFile->h, pFile->locktype));
-
   /* Unix cannot, but some systems may return SQLITE_FULL from here. This
   ** line is to test that doing so does not cause any problems.
   */
   SimulateDiskfullError( return SQLITE_FULL );
 
+  OSTRACE(("SYNC file=%p, flags=%x, lock=%d\n",
+           pFile->h, flags, pFile->locktype));
+
 #ifndef SQLITE_TEST
   UNUSED_PARAMETER(flags);
 #else
@@ -34411,9 +33097,11 @@ static int winSync(sqlite3_file *id, int flags){
   rc = osFlushFileBuffers(pFile->h);
   SimulateIOError( rc=FALSE );
   if( rc ){
+    OSTRACE(("SYNC file=%p, rc=SQLITE_OK\n", pFile->h));
     return SQLITE_OK;
   }else{
     pFile->lastErrno = osGetLastError();
+    OSTRACE(("SYNC file=%p, rc=SQLITE_IOERR_FSYNC\n", pFile->h));
     return winLogError(SQLITE_IOERR_FSYNC, pFile->lastErrno,
              "winSync", pFile->zPath);
   }
@@ -34428,7 +33116,10 @@ static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
   int rc = SQLITE_OK;
 
   assert( id!=0 );
+  assert( pSize!=0 );
   SimulateIOError(return SQLITE_IOERR_FSTAT);
+  OSTRACE(("SIZE file=%p, pSize=%p\n", pFile->h, pSize));
+
 #if SQLITE_OS_WINRT
   {
     FILE_STANDARD_INFO info;
@@ -34457,6 +33148,8 @@ static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
     }
   }
 #endif
+  OSTRACE(("SIZE file=%p, pSize=%p, *pSize=%lld, rc=%s\n",
+           pFile->h, pSize, *pSize, sqlite3ErrName(rc)));
   return rc;
 }
 
@@ -34498,6 +33191,7 @@ static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
 */
 static int getReadLock(winFile *pFile){
   int res;
+  OSTRACE(("READ-LOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
   if( isNT() ){
 #if SQLITE_OS_WINCE
     /*
@@ -34523,6 +33217,7 @@ static int getReadLock(winFile *pFile){
     pFile->lastErrno = osGetLastError();
     /* No need to log a failure to lock */
   }
+  OSTRACE(("READ-LOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
   return res;
 }
 
@@ -34532,6 +33227,7 @@ static int getReadLock(winFile *pFile){
 static int unlockReadLock(winFile *pFile){
   int res;
   DWORD lastErrno;
+  OSTRACE(("READ-UNLOCK file=%p, lock=%d\n", pFile->h, pFile->locktype));
   if( isNT() ){
     res = winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
   }
@@ -34545,6 +33241,7 @@ static int unlockReadLock(winFile *pFile){
     winLogError(SQLITE_IOERR_UNLOCK, pFile->lastErrno,
              "unlockReadLock", pFile->zPath);
   }
+  OSTRACE(("READ-UNLOCK file=%p, rc=%s\n", pFile->h, sqlite3ErrName(res)));
   return res;
 }
 
@@ -34583,14 +33280,15 @@ static int winLock(sqlite3_file *id, int locktype){
   DWORD lastErrno = NO_ERROR;
 
   assert( id!=0 );
-  OSTRACE(("LOCK %d %d was %d(%d)\n",
-           pFile->h, locktype, pFile->locktype, pFile->sharedLockByte));
+  OSTRACE(("LOCK file=%p, oldLock=%d(%d), newLock=%d\n",
+           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
 
   /* If there is already a lock of this type or more restrictive on the
   ** OsFile, do nothing. Don't use the end_lock: exit path, as
   ** sqlite3OsEnterMutex() hasn't been called yet.
   */
   if( pFile->locktype>=locktype ){
+    OSTRACE(("LOCK-HELD file=%p, rc=SQLITE_OK\n", pFile->h));
     return SQLITE_OK;
   }
 
@@ -34618,7 +33316,8 @@ static int winLock(sqlite3_file *id, int locktype){
       ** If you are using this code as a model for alternative VFSes, do not
       ** copy this retry logic.  It is a hack intended for Windows only.
       */
-      OSTRACE(("could not get a PENDING lock. cnt=%d\n", cnt));
+      OSTRACE(("LOCK-PENDING-FAIL file=%p, count=%d, rc=%s\n",
+               pFile->h, cnt, sqlite3ErrName(res)));
       if( cnt ) sqlite3_win32_sleep(1);
     }
     gotPendingLock = res;
@@ -34663,14 +33362,12 @@ static int winLock(sqlite3_file *id, int locktype){
   if( locktype==EXCLUSIVE_LOCK && res ){
     assert( pFile->locktype>=SHARED_LOCK );
     res = unlockReadLock(pFile);
-    OSTRACE(("unreadlock = %d\n", res));
     res = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, SHARED_FIRST, 0,
                       SHARED_SIZE, 0);
     if( res ){
       newLocktype = EXCLUSIVE_LOCK;
     }else{
       lastErrno = osGetLastError();
-      OSTRACE(("error-code = %d\n", lastErrno));
       getReadLock(pFile);
     }
   }
@@ -34688,12 +33385,14 @@ static int winLock(sqlite3_file *id, int locktype){
   if( res ){
     rc = SQLITE_OK;
   }else{
-    OSTRACE(("LOCK FAILED %d trying for %d but got %d\n", pFile->h,
-           locktype, newLocktype));
+    OSTRACE(("LOCK-FAIL file=%p, wanted=%d, got=%d\n",
+             pFile->h, locktype, newLocktype));
     pFile->lastErrno = lastErrno;
     rc = SQLITE_BUSY;
   }
   pFile->locktype = (u8)newLocktype;
+  OSTRACE(("LOCK file=%p, lock=%d, rc=%s\n",
+           pFile->h, pFile->locktype, sqlite3ErrName(rc)));
   return rc;
 }
 
@@ -34707,20 +33406,23 @@ static int winCheckReservedLock(sqlite3_file *id, int *pResOut){
   winFile *pFile = (winFile*)id;
 
   SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
+  OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p\n", pFile->h, pResOut));
 
   assert( id!=0 );
   if( pFile->locktype>=RESERVED_LOCK ){
     rc = 1;
-    OSTRACE(("TEST WR-LOCK %d %d (local)\n", pFile->h, rc));
+    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (local)\n", pFile->h, rc));
   }else{
-    rc = winLockFile(&pFile->h, SQLITE_LOCKFILE_FLAGS, RESERVED_BYTE, 0, 1, 0);
+    rc = winLockFile(&pFile->h, SQLITE_LOCKFILEEX_FLAGS,RESERVED_BYTE, 0, 1, 0);
     if( rc ){
       winUnlockFile(&pFile->h, RESERVED_BYTE, 0, 1, 0);
     }
     rc = !rc;
-    OSTRACE(("TEST WR-LOCK %d %d (remote)\n", pFile->h, rc));
+    OSTRACE(("TEST-WR-LOCK file=%p, rc=%d (remote)\n", pFile->h, rc));
   }
   *pResOut = rc;
+  OSTRACE(("TEST-WR-LOCK file=%p, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
+           pFile->h, pResOut, *pResOut));
   return SQLITE_OK;
 }
 
@@ -34741,8 +33443,8 @@ static int winUnlock(sqlite3_file *id, int locktype){
   int rc = SQLITE_OK;
   assert( pFile!=0 );
   assert( locktype<=SHARED_LOCK );
-  OSTRACE(("UNLOCK %d to %d was %d(%d)\n", pFile->h, locktype,
-          pFile->locktype, pFile->sharedLockByte));
+  OSTRACE(("UNLOCK file=%p, oldLock=%d(%d), newLock=%d\n",
+           pFile->h, pFile->locktype, pFile->sharedLockByte, locktype));
   type = pFile->locktype;
   if( type>=EXCLUSIVE_LOCK ){
     winUnlockFile(&pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
@@ -34763,6 +33465,8 @@ static int winUnlock(sqlite3_file *id, int locktype){
     winUnlockFile(&pFile->h, PENDING_BYTE, 0, 1, 0);
   }
   pFile->locktype = (u8)locktype;
+  OSTRACE(("UNLOCK file=%p, lock=%d, rc=%s\n",
+           pFile->h, pFile->locktype, sqlite3ErrName(rc)));
   return rc;
 }
 
@@ -34782,22 +33486,32 @@ static void winModeBit(winFile *pFile, unsigned char mask, int *pArg){
   }
 }
 
+/* Forward declaration */
+static int getTempname(int nBuf, char *zBuf);
+#if SQLITE_MAX_MMAP_SIZE>0
+static int winMapfile(winFile*, sqlite3_int64);
+#endif
+
 /*
 ** Control and query of the open file handle.
 */
 static int winFileControl(sqlite3_file *id, int op, void *pArg){
   winFile *pFile = (winFile*)id;
+  OSTRACE(("FCNTL file=%p, op=%d, pArg=%p\n", pFile->h, op, pArg));
   switch( op ){
     case SQLITE_FCNTL_LOCKSTATE: {
       *(int*)pArg = pFile->locktype;
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
       return SQLITE_OK;
     }
     case SQLITE_LAST_ERRNO: {
       *(int*)pArg = (int)pFile->lastErrno;
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
       return SQLITE_OK;
     }
     case SQLITE_FCNTL_CHUNK_SIZE: {
       pFile->szChunk = *(int *)pArg;
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
       return SQLITE_OK;
     }
     case SQLITE_FCNTL_SIZE_HINT: {
@@ -34812,20 +33526,25 @@ static int winFileControl(sqlite3_file *id, int op, void *pArg){
             SimulateIOErrorBenign(0);
           }
         }
+        OSTRACE(("FCNTL file=%p, rc=%s\n", pFile->h, sqlite3ErrName(rc)));
         return rc;
       }
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
       return SQLITE_OK;
     }
     case SQLITE_FCNTL_PERSIST_WAL: {
       winModeBit(pFile, WINFILE_PERSIST_WAL, (int*)pArg);
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
       return SQLITE_OK;
     }
     case SQLITE_FCNTL_POWERSAFE_OVERWRITE: {
       winModeBit(pFile, WINFILE_PSOW, (int*)pArg);
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
       return SQLITE_OK;
     }
     case SQLITE_FCNTL_VFSNAME: {
       *(char**)pArg = sqlite3_mprintf("win32");
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
       return SQLITE_OK;
     }
     case SQLITE_FCNTL_WIN32_AV_RETRY: {
@@ -34840,9 +33559,39 @@ static int winFileControl(sqlite3_file *id, int op, void *pArg){
       }else{
         a[1] = win32IoerrRetryDelay;
       }
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
       return SQLITE_OK;
     }
+    case SQLITE_FCNTL_TEMPFILENAME: {
+      char *zTFile = sqlite3MallocZero( pFile->pVfs->mxPathname );
+      if( zTFile ){
+        getTempname(pFile->pVfs->mxPathname, zTFile);
+        *(char**)pArg = zTFile;
+      }
+      OSTRACE(("FCNTL file=%p, rc=SQLITE_OK\n", pFile->h));
+      return SQLITE_OK;
+    }
+#if SQLITE_MAX_MMAP_SIZE>0
+    case SQLITE_FCNTL_MMAP_SIZE: {
+      i64 newLimit = *(i64*)pArg;
+      int rc = SQLITE_OK;
+      if( newLimit>sqlite3GlobalConfig.mxMmap ){
+        newLimit = sqlite3GlobalConfig.mxMmap;
+      }
+      *(i64*)pArg = pFile->mmapSizeMax;
+      if( newLimit>=0 && newLimit!=pFile->mmapSizeMax && pFile->nFetchOut==0 ){
+        pFile->mmapSizeMax = newLimit;
+        if( pFile->mmapSize>0 ){
+          (void)winUnmapfile(pFile);
+          rc = winMapfile(pFile, -1);
+        }
+      }
+      OSTRACE(("FCNTL file=%p, rc=%d\n", pFile->h, rc));
+      return rc;
+    }
+#endif
   }
+  OSTRACE(("FCNTL file=%p, rc=SQLITE_NOTFOUND\n", pFile->h));
   return SQLITE_NOTFOUND;
 }
 
@@ -34870,8 +33619,6 @@ static int winDeviceCharacteristics(sqlite3_file *id){
          ((p->ctrlFlags & WINFILE_PSOW)?SQLITE_IOCAP_POWERSAFE_OVERWRITE:0);
 }
 
-#ifndef SQLITE_OMIT_WAL
-
 /* 
 ** Windows will only let you create file view mappings
 ** on allocation size granularity boundaries.
@@ -34880,6 +33627,8 @@ static int winDeviceCharacteristics(sqlite3_file *id){
 */
 SYSTEM_INFO winSysInfo;
 
+#ifndef SQLITE_OMIT_WAL
+
 /*
 ** Helper functions to obtain and relinquish the global mutex. The
 ** global mutex is used to protect the winLockInfo objects used by 
@@ -35003,6 +33752,9 @@ static int winShmSystemLock(
   /* Access to the winShmNode object is serialized by the caller */
   assert( sqlite3_mutex_held(pFile->mutex) || pFile->nRef==0 );
 
+  OSTRACE(("SHM-LOCK file=%p, lock=%d, offset=%d, size=%d\n",
+           pFile->hFile.h, lockType, ofst, nByte));
+
   /* Release/Acquire the system-level lock */
   if( lockType==_SHM_UNLCK ){
     rc = winUnlockFile(&pFile->hFile.h, ofst, 0, nByte, 0);
@@ -35020,11 +33772,9 @@ static int winShmSystemLock(
     rc = SQLITE_BUSY;
   }
 
-  OSTRACE(("SHM-LOCK %d %s %s 0x%08lx\n", 
-           pFile->hFile.h,
-           rc==SQLITE_OK ? "ok" : "failed",
-           lockType==_SHM_UNLCK ? "UnlockFileEx" : "LockFileEx",
-           pFile->lastErrno));
+  OSTRACE(("SHM-LOCK file=%p, func=%s, errno=%lu, rc=%s\n",
+           pFile->hFile.h, (lockType == _SHM_UNLCK) ? "winUnlockFile" :
+           "winLockFile", pFile->lastErrno, sqlite3ErrName(rc)));
 
   return rc;
 }
@@ -35044,6 +33794,8 @@ static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
   winShmNode *p;
   BOOL bRc;
   assert( winShmMutexHeld() );
+  OSTRACE(("SHM-PURGE pid=%lu, deleteFlag=%d\n",
+           osGetCurrentProcessId(), deleteFlag));
   pp = &winShmNodeList;
   while( (p = *pp)!=0 ){
     if( p->nRef==0 ){
@@ -35051,15 +33803,13 @@ static void winShmPurge(sqlite3_vfs *pVfs, int deleteFlag){
       if( p->mutex ) sqlite3_mutex_free(p->mutex);
       for(i=0; i<p->nRegion; i++){
         bRc = osUnmapViewOfFile(p->aRegion[i].pMap);
-        OSTRACE(("SHM-PURGE pid-%d unmap region=%d %s\n",
-                 (int)osGetCurrentProcessId(), i,
-                 bRc ? "ok" : "failed"));
+        OSTRACE(("SHM-PURGE-UNMAP pid=%lu, region=%d, rc=%s\n",
+                 osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
         bRc = osCloseHandle(p->aRegion[i].hMap);
-        OSTRACE(("SHM-PURGE pid-%d close region=%d %s\n",
-                 (int)osGetCurrentProcessId(), i,
-                 bRc ? "ok" : "failed"));
+        OSTRACE(("SHM-PURGE-CLOSE pid=%lu, region=%d, rc=%s\n",
+                 osGetCurrentProcessId(), i, bRc ? "ok" : "failed"));
       }
-      if( p->hFile.h != INVALID_HANDLE_VALUE ){
+      if( p->hFile.h!=NULL && p->hFile.h!=INVALID_HANDLE_VALUE ){
         SimulateIOErrorBenign(1);
         winClose((sqlite3_file *)&p->hFile);
         SimulateIOErrorBenign(0);
@@ -35099,16 +33849,14 @@ static int winOpenSharedMemory(winFile *pDbFd){
   /* Allocate space for the new sqlite3_shm object.  Also speculatively
   ** allocate space for a new winShmNode and filename.
   */
-  p = sqlite3_malloc( sizeof(*p) );
+  p = sqlite3MallocZero( sizeof(*p) );
   if( p==0 ) return SQLITE_IOERR_NOMEM;
-  memset(p, 0, sizeof(*p));
   nName = sqlite3Strlen30(pDbFd->zPath);
-  pNew = sqlite3_malloc( sizeof(*pShmNode) + nName + 17 );
+  pNew = sqlite3MallocZero( sizeof(*pShmNode) + nName + 17 );
   if( pNew==0 ){
     sqlite3_free(p);
     return SQLITE_IOERR_NOMEM;
   }
-  memset(pNew, 0, sizeof(*pNew) + nName + 17);
   pNew->zFilename = (char*)&pNew[1];
   sqlite3_snprintf(nName+15, pNew->zFilename, "%s-shm", pDbFd->zPath);
   sqlite3FileSuffix3(pDbFd->zPath, pNew->zFilename); 
@@ -35141,7 +33889,7 @@ static int winOpenSharedMemory(winFile *pDbFd){
     rc = winOpen(pDbFd->pVfs,
                  pShmNode->zFilename,             /* Name of the file (UTF-8) */
                  (sqlite3_file*)&pShmNode->hFile,  /* File handle here */
-                 SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, /* Mode flags */
+                 SQLITE_OPEN_WAL | SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE,
                  0);
     if( SQLITE_OK!=rc ){
       goto shm_open_err;
@@ -35338,9 +34086,9 @@ static int winShmLock(
     }
   }
   sqlite3_mutex_leave(pShmNode->mutex);
-  OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x %s\n",
-           p->id, (int)osGetCurrentProcessId(), p->sharedMask, p->exclMask,
-           rc ? "failed" : "ok"));
+  OSTRACE(("SHM-LOCK pid=%lu, id=%d, sharedMask=%03x, exclMask=%03x, rc=%s\n",
+           osGetCurrentProcessId(), p->id, p->sharedMask, p->exclMask,
+           sqlite3ErrName(rc)));
   return rc;
 }
 
@@ -35445,20 +34193,24 @@ static int winShmMap(
     pShmNode->aRegion = apNew;
 
     while( pShmNode->nRegion<=iRegion ){
-      HANDLE hMap;                /* file-mapping handle */
+      HANDLE hMap = NULL;         /* file-mapping handle */
       void *pMap = 0;             /* Mapped memory region */
      
 #if SQLITE_OS_WINRT
       hMap = osCreateFileMappingFromApp(pShmNode->hFile.h,
           NULL, PAGE_READWRITE, nByte, NULL
       );
-#else
+#elif defined(SQLITE_WIN32_HAS_WIDE)
       hMap = osCreateFileMappingW(pShmNode->hFile.h, 
           NULL, PAGE_READWRITE, 0, nByte, NULL
       );
+#elif defined(SQLITE_WIN32_HAS_ANSI)
+      hMap = osCreateFileMappingA(pShmNode->hFile.h, 
+          NULL, PAGE_READWRITE, 0, nByte, NULL
+      );
 #endif
-      OSTRACE(("SHM-MAP pid-%d create region=%d nbyte=%d %s\n",
-               (int)osGetCurrentProcessId(), pShmNode->nRegion, nByte,
+      OSTRACE(("SHM-MAP-CREATE pid=%lu, region=%d, size=%d, rc=%s\n",
+               osGetCurrentProcessId(), pShmNode->nRegion, nByte,
                hMap ? "ok" : "failed"));
       if( hMap ){
         int iOffset = pShmNode->nRegion*szRegion;
@@ -35472,8 +34224,8 @@ static int winShmMap(
             0, iOffset - iOffsetShift, szRegion + iOffsetShift
         );
 #endif
-        OSTRACE(("SHM-MAP pid-%d map region=%d offset=%d size=%d %s\n",
-                 (int)osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
+        OSTRACE(("SHM-MAP-MAP pid=%lu, region=%d, offset=%d, size=%d, rc=%s\n",
+                 osGetCurrentProcessId(), pShmNode->nRegion, iOffset,
                  szRegion, pMap ? "ok" : "failed"));
       }
       if( !pMap ){
@@ -35510,6 +34262,230 @@ shmpage_out:
 # define winShmUnmap   0
 #endif /* #ifndef SQLITE_OMIT_WAL */
 
+/*
+** Cleans up the mapped region of the specified file, if any.
+*/
+#if SQLITE_MAX_MMAP_SIZE>0
+static int winUnmapfile(winFile *pFile){
+  assert( pFile!=0 );
+  OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, pMapRegion=%p, "
+           "mmapSize=%lld, mmapSizeActual=%lld, mmapSizeMax=%lld\n",
+           osGetCurrentProcessId(), pFile, pFile->hMap, pFile->pMapRegion,
+           pFile->mmapSize, pFile->mmapSizeActual, pFile->mmapSizeMax));
+  if( pFile->pMapRegion ){
+    if( !osUnmapViewOfFile(pFile->pMapRegion) ){
+      pFile->lastErrno = osGetLastError();
+      OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, pMapRegion=%p, "
+               "rc=SQLITE_IOERR_MMAP\n", osGetCurrentProcessId(), pFile,
+               pFile->pMapRegion));
+      return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
+                         "winUnmap1", pFile->zPath);
+    }
+    pFile->pMapRegion = 0;
+    pFile->mmapSize = 0;
+    pFile->mmapSizeActual = 0;
+  }
+  if( pFile->hMap!=NULL ){
+    if( !osCloseHandle(pFile->hMap) ){
+      pFile->lastErrno = osGetLastError();
+      OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, hMap=%p, rc=SQLITE_IOERR_MMAP\n",
+               osGetCurrentProcessId(), pFile, pFile->hMap));
+      return winLogError(SQLITE_IOERR_MMAP, pFile->lastErrno,
+                         "winUnmap2", pFile->zPath);
+    }
+    pFile->hMap = NULL;
+  }
+  OSTRACE(("UNMAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+           osGetCurrentProcessId(), pFile));
+  return SQLITE_OK;
+}
+
+/*
+** Memory map or remap the file opened by file-descriptor pFd (if the file
+** is already mapped, the existing mapping is replaced by the new). Or, if 
+** there already exists a mapping for this file, and there are still 
+** outstanding xFetch() references to it, this function is a no-op.
+**
+** If parameter nByte is non-negative, then it is the requested size of 
+** the mapping to create. Otherwise, if nByte is less than zero, then the 
+** requested size is the size of the file on disk. The actual size of the
+** created mapping is either the requested size or the value configured 
+** using SQLITE_FCNTL_MMAP_SIZE, whichever is smaller.
+**
+** SQLITE_OK is returned if no error occurs (even if the mapping is not
+** recreated as a result of outstanding references) or an SQLite error
+** code otherwise.
+*/
+static int winMapfile(winFile *pFd, sqlite3_int64 nByte){
+  sqlite3_int64 nMap = nByte;
+  int rc;
+
+  assert( nMap>=0 || pFd->nFetchOut==0 );
+  OSTRACE(("MAP-FILE pid=%lu, pFile=%p, size=%lld\n",
+           osGetCurrentProcessId(), pFd, nByte));
+
+  if( pFd->nFetchOut>0 ) return SQLITE_OK;
+
+  if( nMap<0 ){
+    rc = winFileSize((sqlite3_file*)pFd, &nMap);
+    if( rc ){
+      OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_IOERR_FSTAT\n",
+               osGetCurrentProcessId(), pFd));
+      return SQLITE_IOERR_FSTAT;
+    }
+  }
+  if( nMap>pFd->mmapSizeMax ){
+    nMap = pFd->mmapSizeMax;
+  }
+  nMap &= ~(sqlite3_int64)(winSysInfo.dwPageSize - 1);
+ 
+  if( nMap==0 && pFd->mmapSize>0 ){
+    winUnmapfile(pFd);
+  }
+  if( nMap!=pFd->mmapSize ){
+    void *pNew = 0;
+    DWORD protect = PAGE_READONLY;
+    DWORD flags = FILE_MAP_READ;
+
+    winUnmapfile(pFd);
+    if( (pFd->ctrlFlags & WINFILE_RDONLY)==0 ){
+      protect = PAGE_READWRITE;
+      flags |= FILE_MAP_WRITE;
+    }
+#if SQLITE_OS_WINRT
+    pFd->hMap = osCreateFileMappingFromApp(pFd->h, NULL, protect, nMap, NULL);
+#elif defined(SQLITE_WIN32_HAS_WIDE)
+    pFd->hMap = osCreateFileMappingW(pFd->h, NULL, protect,
+                                (DWORD)((nMap>>32) & 0xffffffff),
+                                (DWORD)(nMap & 0xffffffff), NULL);
+#elif defined(SQLITE_WIN32_HAS_ANSI)
+    pFd->hMap = osCreateFileMappingA(pFd->h, NULL, protect,
+                                (DWORD)((nMap>>32) & 0xffffffff),
+                                (DWORD)(nMap & 0xffffffff), NULL);
+#endif
+    if( pFd->hMap==NULL ){
+      pFd->lastErrno = osGetLastError();
+      rc = winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
+                       "winMapfile", pFd->zPath);
+      /* Log the error, but continue normal operation using xRead/xWrite */
+      OSTRACE(("MAP-FILE-CREATE pid=%lu, pFile=%p, rc=SQLITE_IOERR_MMAP\n",
+               osGetCurrentProcessId(), pFd));
+      return SQLITE_OK;
+    }
+    assert( (nMap % winSysInfo.dwPageSize)==0 );
+    assert( sizeof(SIZE_T)==sizeof(sqlite3_int64) || nMap<=0xffffffff );
+#if SQLITE_OS_WINRT
+    pNew = osMapViewOfFileFromApp(pFd->hMap, flags, 0, (SIZE_T)nMap);
+#else
+    pNew = osMapViewOfFile(pFd->hMap, flags, 0, 0, (SIZE_T)nMap);
+#endif
+    if( pNew==NULL ){
+      osCloseHandle(pFd->hMap);
+      pFd->hMap = NULL;
+      pFd->lastErrno = osGetLastError();
+      winLogError(SQLITE_IOERR_MMAP, pFd->lastErrno,
+                  "winMapfile", pFd->zPath);
+      OSTRACE(("MAP-FILE-MAP pid=%lu, pFile=%p, rc=SQLITE_IOERR_MMAP\n",
+               osGetCurrentProcessId(), pFd));
+      return SQLITE_OK;
+    }
+    pFd->pMapRegion = pNew;
+    pFd->mmapSize = nMap;
+    pFd->mmapSizeActual = nMap;
+  }
+
+  OSTRACE(("MAP-FILE pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+           osGetCurrentProcessId(), pFd));
+  return SQLITE_OK;
+}
+#endif /* SQLITE_MAX_MMAP_SIZE>0 */
+
+/*
+** If possible, return a pointer to a mapping of file fd starting at offset
+** iOff. The mapping must be valid for at least nAmt bytes.
+**
+** If such a pointer can be obtained, store it in *pp and return SQLITE_OK.
+** Or, if one cannot but no error occurs, set *pp to 0 and return SQLITE_OK.
+** Finally, if an error does occur, return an SQLite error code. The final
+** value of *pp is undefined in this case.
+**
+** If this function does return a pointer, the caller must eventually 
+** release the reference by calling winUnfetch().
+*/
+static int winFetch(sqlite3_file *fd, i64 iOff, int nAmt, void **pp){
+#if SQLITE_MAX_MMAP_SIZE>0
+  winFile *pFd = (winFile*)fd;   /* The underlying database file */
+#endif
+  *pp = 0;
+
+  OSTRACE(("FETCH pid=%lu, pFile=%p, offset=%lld, amount=%d, pp=%p\n",
+           osGetCurrentProcessId(), fd, iOff, nAmt, pp));
+
+#if SQLITE_MAX_MMAP_SIZE>0
+  if( pFd->mmapSizeMax>0 ){
+    if( pFd->pMapRegion==0 ){
+      int rc = winMapfile(pFd, -1);
+      if( rc!=SQLITE_OK ){
+        OSTRACE(("FETCH pid=%lu, pFile=%p, rc=%s\n",
+                 osGetCurrentProcessId(), pFd, sqlite3ErrName(rc)));
+        return rc;
+      }
+    }
+    if( pFd->mmapSize >= iOff+nAmt ){
+      *pp = &((u8 *)pFd->pMapRegion)[iOff];
+      pFd->nFetchOut++;
+    }
+  }
+#endif
+
+  OSTRACE(("FETCH pid=%lu, pFile=%p, pp=%p, *pp=%p, rc=SQLITE_OK\n",
+           osGetCurrentProcessId(), fd, pp, *pp));
+  return SQLITE_OK;
+}
+
+/*
+** If the third argument is non-NULL, then this function releases a 
+** reference obtained by an earlier call to winFetch(). The second
+** argument passed to this function must be the same as the corresponding
+** argument that was passed to the winFetch() invocation. 
+**
+** Or, if the third argument is NULL, then this function is being called 
+** to inform the VFS layer that, according to POSIX, any existing mapping 
+** may now be invalid and should be unmapped.
+*/
+static int winUnfetch(sqlite3_file *fd, i64 iOff, void *p){
+#if SQLITE_MAX_MMAP_SIZE>0
+  winFile *pFd = (winFile*)fd;   /* The underlying database file */
+
+  /* If p==0 (unmap the entire file) then there must be no outstanding 
+  ** xFetch references. Or, if p!=0 (meaning it is an xFetch reference),
+  ** then there must be at least one outstanding.  */
+  assert( (p==0)==(pFd->nFetchOut==0) );
+
+  /* If p!=0, it must match the iOff value. */
+  assert( p==0 || p==&((u8 *)pFd->pMapRegion)[iOff] );
+
+  OSTRACE(("UNFETCH pid=%lu, pFile=%p, offset=%lld, p=%p\n",
+           osGetCurrentProcessId(), pFd, iOff, p));
+
+  if( p ){
+    pFd->nFetchOut--;
+  }else{
+    /* FIXME:  If Windows truly always prevents truncating or deleting a
+    ** file while a mapping is held, then the following winUnmapfile() call
+    ** is unnecessary can can be omitted - potentially improving
+    ** performance.  */
+    winUnmapfile(pFd);
+  }
+
+  assert( pFd->nFetchOut>=0 );
+#endif
+
+  OSTRACE(("UNFETCH pid=%lu, pFile=%p, rc=SQLITE_OK\n",
+           osGetCurrentProcessId(), fd));
+  return SQLITE_OK;
+}
+
 /*
 ** Here ends the implementation of all sqlite3_file methods.
 **
@@ -35521,7 +34497,7 @@ shmpage_out:
 ** sqlite3_file for win32.
 */
 static const sqlite3_io_methods winIoMethod = {
-  2,                              /* iVersion */
+  3,                              /* iVersion */
   winClose,                       /* xClose */
   winRead,                        /* xRead */
   winWrite,                       /* xWrite */
@@ -35537,7 +34513,9 @@ static const sqlite3_io_methods winIoMethod = {
   winShmMap,                      /* xShmMap */
   winShmLock,                     /* xShmLock */
   winShmBarrier,                  /* xShmBarrier */
-  winShmUnmap                     /* xShmUnmap */
+  winShmUnmap,                    /* xShmUnmap */
+  winFetch,                       /* xFetch */
+  winUnfetch                      /* xUnfetch */
 };
 
 /****************************************************************************
@@ -35567,6 +34545,15 @@ static void *convertUtf8Filename(const char *zFilename){
   return zConverted;
 }
 
+/*
+** Maximum pathname length (in bytes) for windows.  The MAX_PATH macro is
+** in characters, so we allocate 3 bytes per character assuming worst-case
+** 3-bytes-per-character UTF8.
+*/
+#ifndef SQLITE_WIN32_MAX_PATH
+#  define SQLITE_WIN32_MAX_PATH   (MAX_PATH*3)
+#endif
+
 /*
 ** Create a temporary file name in zBuf.  zBuf must be big enough to
 ** hold at pVfs->mxPathname characters.
@@ -35578,7 +34565,7 @@ static int getTempname(int nBuf, char *zBuf){
     "0123456789";
   size_t i, j;
   int nTempPath;
-  char zTempPath[MAX_PATH+2];
+  char zTempPath[SQLITE_WIN32_MAX_PATH+2];
 
   /* It's odd to simulate an io-error here, but really this is just
   ** using the io-error infrastructure to test that SQLite handles this
@@ -35586,39 +34573,62 @@ static int getTempname(int nBuf, char *zBuf){
   */
   SimulateIOError( return SQLITE_IOERR );
 
-  memset(zTempPath, 0, MAX_PATH+2);
-
   if( sqlite3_temp_directory ){
-    sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory);
+    sqlite3_snprintf(SQLITE_WIN32_MAX_PATH-30, zTempPath, "%s",
+                     sqlite3_temp_directory);
   }
 #if !SQLITE_OS_WINRT
   else if( isNT() ){
     char *zMulti;
     WCHAR zWidePath[MAX_PATH];
-    osGetTempPathW(MAX_PATH-30, zWidePath);
+    if( osGetTempPathW(MAX_PATH-30, zWidePath)==0 ){
+      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
+      return SQLITE_IOERR_GETTEMPPATH;
+    }
     zMulti = unicodeToUtf8(zWidePath);
     if( zMulti ){
-      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zMulti);
+      sqlite3_snprintf(SQLITE_WIN32_MAX_PATH-30, zTempPath, "%s", zMulti);
       sqlite3_free(zMulti);
     }else{
+      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
       return SQLITE_IOERR_NOMEM;
     }
   }
 #ifdef SQLITE_WIN32_HAS_ANSI
   else{
     char *zUtf8;
-    char zMbcsPath[MAX_PATH];
-    osGetTempPathA(MAX_PATH-30, zMbcsPath);
+    char zMbcsPath[SQLITE_WIN32_MAX_PATH];
+    if( osGetTempPathA(SQLITE_WIN32_MAX_PATH-30, zMbcsPath)==0 ){
+      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_GETTEMPPATH\n"));
+      return SQLITE_IOERR_GETTEMPPATH;
+    }
     zUtf8 = sqlite3_win32_mbcs_to_utf8(zMbcsPath);
     if( zUtf8 ){
-      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", zUtf8);
+      sqlite3_snprintf(SQLITE_WIN32_MAX_PATH-30, zTempPath, "%s", zUtf8);
       sqlite3_free(zUtf8);
     }else{
+      OSTRACE(("TEMP-FILENAME rc=SQLITE_IOERR_NOMEM\n"));
       return SQLITE_IOERR_NOMEM;
     }
   }
-#endif
-#endif
+#else
+  else{
+    /*
+    ** Compiled without ANSI support and the current operating system
+    ** is not Windows NT; therefore, just zero the temporary buffer.
+    */
+    memset(zTempPath, 0, SQLITE_WIN32_MAX_PATH+2);
+  }
+#endif /* SQLITE_WIN32_HAS_ANSI */
+#else
+  else{
+    /*
+    ** Compiled for WinRT and the sqlite3_temp_directory is not set;
+    ** therefore, just zero the temporary buffer.
+    */
+    memset(zTempPath, 0, SQLITE_WIN32_MAX_PATH+2);
+  }
+#endif /* !SQLITE_OS_WINRT */
 
   /* Check that the output buffer is large enough for the temporary file 
   ** name. If it is not, return SQLITE_ERROR.
@@ -35626,6 +34636,7 @@ static int getTempname(int nBuf, char *zBuf){
   nTempPath = sqlite3Strlen30(zTempPath);
 
   if( (nTempPath + sqlite3Strlen30(SQLITE_TEMP_FILE_PREFIX) + 18) >= nBuf ){
+    OSTRACE(("TEMP-FILENAME rc=SQLITE_ERROR\n"));
     return SQLITE_ERROR;
   }
 
@@ -35643,8 +34654,8 @@ static int getTempname(int nBuf, char *zBuf){
   zBuf[j] = 0;
   zBuf[j+1] = 0;
 
-  OSTRACE(("TEMP FILENAME: %s\n", zBuf));
-  return SQLITE_OK; 
+  OSTRACE(("TEMP-FILENAME name=%s, rc=SQLITE_OK\n", zBuf));
+  return SQLITE_OK;
 }
 
 /*
@@ -35703,7 +34714,7 @@ static int winOpen(
   /* If argument zPath is a NULL pointer, this function is required to open
   ** a temporary file. Use this buffer to store the file name in.
   */
-  char zTmpname[MAX_PATH+2];     /* Buffer used to create temp filename */
+  char zTmpname[SQLITE_WIN32_MAX_PATH+2];     /* Buffer used to create temp filename */
 
   int rc = SQLITE_OK;            /* Function Return Code */
 #if !defined(NDEBUG) || SQLITE_OS_WINCE
@@ -35713,9 +34724,7 @@ static int winOpen(
   int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
   int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
   int isCreate     = (flags & SQLITE_OPEN_CREATE);
-#ifndef NDEBUG
   int isReadonly   = (flags & SQLITE_OPEN_READONLY);
-#endif
   int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
 
 #ifndef NDEBUG
@@ -35726,6 +34735,9 @@ static int winOpen(
   ));
 #endif
 
+  OSTRACE(("OPEN name=%s, pFile=%p, flags=%x, pOutFlags=%p\n",
+           zUtf8Name, id, flags, pOutFlags));
+
   /* Check the following statements are true: 
   **
   **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
@@ -35752,18 +34764,25 @@ static int winOpen(
        || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
   );
 
-  assert( id!=0 );
-  UNUSED_PARAMETER(pVfs);
-
+  assert( pFile!=0 );
+  memset(pFile, 0, sizeof(winFile));
   pFile->h = INVALID_HANDLE_VALUE;
 
+#if SQLITE_OS_WINRT
+  if( !sqlite3_temp_directory ){
+    sqlite3_log(SQLITE_ERROR,
+        "sqlite3_temp_directory variable should be set for WinRT");
+  }
+#endif
+
   /* If the second argument to this function is NULL, generate a 
   ** temporary file name to use 
   */
   if( !zUtf8Name ){
     assert(isDelete && !isOpenJournal);
-    rc = getTempname(MAX_PATH+2, zTmpname);
+    rc = getTempname(SQLITE_WIN32_MAX_PATH+2, zTmpname);
     if( rc!=SQLITE_OK ){
+      OSTRACE(("OPEN name=%s, rc=%s", zUtf8Name, sqlite3ErrName(rc)));
       return rc;
     }
     zUtf8Name = zTmpname;
@@ -35779,11 +34798,13 @@ static int winOpen(
   /* Convert the filename to the system encoding. */
   zConverted = convertUtf8Filename(zUtf8Name);
   if( zConverted==0 ){
+    OSTRACE(("OPEN name=%s, rc=SQLITE_IOERR_NOMEM", zUtf8Name));
     return SQLITE_IOERR_NOMEM;
   }
 
   if( winIsDir(zConverted) ){
     sqlite3_free(zConverted);
+    OSTRACE(("OPEN name=%s, rc=SQLITE_CANTOPEN_ISDIR", zUtf8Name));
     return SQLITE_CANTOPEN_ISDIR;
   }
 
@@ -35874,9 +34895,8 @@ static int winOpen(
 #endif
   logIoerr(cnt);
 
-  OSTRACE(("OPEN %d %s 0x%lx %s\n", 
-           h, zName, dwDesiredAccess, 
-           h==INVALID_HANDLE_VALUE ? "failed" : "ok"));
+  OSTRACE(("OPEN file=%p, name=%s, access=%lx, rc=%s\n", h, zUtf8Name,
+           dwDesiredAccess, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
 
   if( h==INVALID_HANDLE_VALUE ){
     pFile->lastErrno = lastErrno;
@@ -35884,7 +34904,9 @@ static int winOpen(
     sqlite3_free(zConverted);
     if( isReadWrite && !isExclusive ){
       return winOpen(pVfs, zName, id, 
-             ((flags|SQLITE_OPEN_READONLY)&~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)), pOutFlags);
+         ((flags|SQLITE_OPEN_READONLY) &
+                     ~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
+         pOutFlags);
     }else{
       return SQLITE_CANTOPEN_BKPT;
     }
@@ -35898,24 +34920,18 @@ static int winOpen(
     }
   }
 
-  memset(pFile, 0, sizeof(*pFile));
-  pFile->pMethod = &winIoMethod;
-  pFile->h = h;
-  pFile->lastErrno = NO_ERROR;
-  pFile->pVfs = pVfs;
-  pFile->pShm = 0;
-  pFile->zPath = zName;
-  if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
-    pFile->ctrlFlags |= WINFILE_PSOW;
-  }
+  OSTRACE(("OPEN file=%p, name=%s, access=%lx, pOutFlags=%p, *pOutFlags=%d, "
+           "rc=%s\n", h, zUtf8Name, dwDesiredAccess, pOutFlags, pOutFlags ?
+           *pOutFlags : 0, (h==INVALID_HANDLE_VALUE) ? "failed" : "ok"));
 
 #if SQLITE_OS_WINCE
   if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB
-       && !winceCreateLock(zName, pFile)
+       && (rc = winceCreateLock(zName, pFile))!=SQLITE_OK
   ){
     osCloseHandle(h);
     sqlite3_free(zConverted);
-    return SQLITE_CANTOPEN_BKPT;
+    OSTRACE(("OPEN-CE-LOCK name=%s, rc=%s\n", zName, sqlite3ErrName(rc)));
+    return rc;
   }
   if( isTemp ){
     pFile->zDeleteOnClose = zConverted;
@@ -35925,6 +34941,25 @@ static int winOpen(
     sqlite3_free(zConverted);
   }
 
+  pFile->pMethod = &winIoMethod;
+  pFile->pVfs = pVfs;
+  pFile->h = h;
+  if( isReadonly ){
+    pFile->ctrlFlags |= WINFILE_RDONLY;
+  }
+  if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
+    pFile->ctrlFlags |= WINFILE_PSOW;
+  }
+  pFile->lastErrno = NO_ERROR;
+  pFile->zPath = zName;
+#if SQLITE_MAX_MMAP_SIZE>0
+  pFile->hMap = NULL;
+  pFile->pMapRegion = 0;
+  pFile->mmapSize = 0;
+  pFile->mmapSizeActual = 0;
+  pFile->mmapSizeMax = sqlite3GlobalConfig.szMmap;
+#endif
+
   OpenCounter(+1);
   return rc;
 }
@@ -35955,6 +34990,8 @@ static int winDelete(
   UNUSED_PARAMETER(syncDir);
 
   SimulateIOError(return SQLITE_IOERR_DELETE);
+  OSTRACE(("DELETE name=%s, syncDir=%d\n", zFilename, syncDir));
+
   zConverted = convertUtf8Filename(zFilename);
   if( zConverted==0 ){
     return SQLITE_IOERR_NOMEM;
@@ -35968,14 +35005,26 @@ static int winDelete(
                                   &sAttrData) ){
         attr = sAttrData.dwFileAttributes;
       }else{
-        rc = SQLITE_OK; /* Already gone? */
+        lastErrno = osGetLastError();
+        if( lastErrno==ERROR_FILE_NOT_FOUND
+         || lastErrno==ERROR_PATH_NOT_FOUND ){
+          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+        }else{
+          rc = SQLITE_ERROR;
+        }
         break;
       }
 #else
       attr = osGetFileAttributesW(zConverted);
 #endif
       if ( attr==INVALID_FILE_ATTRIBUTES ){
-        rc = SQLITE_OK; /* Already gone? */
+        lastErrno = osGetLastError();
+        if( lastErrno==ERROR_FILE_NOT_FOUND
+         || lastErrno==ERROR_PATH_NOT_FOUND ){
+          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+        }else{
+          rc = SQLITE_ERROR;
+        }
         break;
       }
       if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
@@ -35997,7 +35046,13 @@ static int winDelete(
     do {
       attr = osGetFileAttributesA(zConverted);
       if ( attr==INVALID_FILE_ATTRIBUTES ){
-        rc = SQLITE_OK; /* Already gone? */
+        lastErrno = osGetLastError();
+        if( lastErrno==ERROR_FILE_NOT_FOUND
+         || lastErrno==ERROR_PATH_NOT_FOUND ){
+          rc = SQLITE_IOERR_DELETE_NOENT; /* Already gone? */
+        }else{
+          rc = SQLITE_ERROR;
+        }
         break;
       }
       if ( attr&FILE_ATTRIBUTE_DIRECTORY ){
@@ -36015,19 +35070,19 @@ static int winDelete(
     } while(1);
   }
 #endif
-  if( rc ){
+  if( rc && rc!=SQLITE_IOERR_DELETE_NOENT ){
     rc = winLogError(SQLITE_IOERR_DELETE, lastErrno,
              "winDelete", zFilename);
   }else{
     logIoerr(cnt);
   }
   sqlite3_free(zConverted);
-  OSTRACE(("DELETE \"%s\" %s\n", zFilename, (rc ? "failed" : "ok" )));
+  OSTRACE(("DELETE name=%s, rc=%s\n", zFilename, sqlite3ErrName(rc)));
   return rc;
 }
 
 /*
-** Check the existance and status of a file.
+** Check the existence and status of a file.
 */
 static int winAccess(
   sqlite3_vfs *pVfs,         /* Not used on win32 */
@@ -36042,8 +35097,12 @@ static int winAccess(
   UNUSED_PARAMETER(pVfs);
 
   SimulateIOError( return SQLITE_IOERR_ACCESS; );
+  OSTRACE(("ACCESS name=%s, flags=%x, pResOut=%p\n",
+           zFilename, flags, pResOut));
+
   zConverted = convertUtf8Filename(zFilename);
   if( zConverted==0 ){
+    OSTRACE(("ACCESS name=%s, rc=SQLITE_IOERR_NOMEM\n", zFilename));
     return SQLITE_IOERR_NOMEM;
   }
   if( isNT() ){
@@ -36066,7 +35125,7 @@ static int winAccess(
       }
     }else{
       logIoerr(cnt);
-      if( lastErrno!=ERROR_FILE_NOT_FOUND ){
+      if( lastErrno!=ERROR_FILE_NOT_FOUND && lastErrno!=ERROR_PATH_NOT_FOUND ){
         winLogError(SQLITE_IOERR_ACCESS, lastErrno, "winAccess", zFilename);
         sqlite3_free(zConverted);
         return SQLITE_IOERR_ACCESS;
@@ -36094,6 +35153,8 @@ static int winAccess(
       assert(!"Invalid flags argument");
   }
   *pResOut = rc;
+  OSTRACE(("ACCESS name=%s, pResOut=%p, *pResOut=%d, rc=SQLITE_OK\n",
+           zFilename, pResOut, *pResOut));
   return SQLITE_OK;
 }
 
@@ -36150,7 +35211,7 @@ static int winFullPathname(
 #if defined(__CYGWIN__)
   SimulateIOError( return SQLITE_ERROR );
   UNUSED_PARAMETER(nFull);
-  assert( pVfs->mxPathname>=MAX_PATH );
+  assert( pVfs->mxPathname>=SQLITE_WIN32_MAX_PATH );
   assert( nFull>=pVfs->mxPathname );
   if ( sqlite3_data_directory && !winIsVerbatimPathname(zRelative) ){
     /*
@@ -36159,18 +35220,21 @@ static int winFullPathname(
     **       for converting the relative path name to an absolute
     **       one by prepending the data directory and a slash.
     */
-    char zOut[MAX_PATH+1];
-    memset(zOut, 0, MAX_PATH+1);
-    cygwin_conv_to_win32_path(zRelative, zOut); /* POSIX to Win32 */
+    char zOut[SQLITE_WIN32_MAX_PATH+1];
+    if( cygwin_conv_path(CCP_POSIX_TO_WIN_A|CCP_RELATIVE, zRelative, zOut,
+                         SQLITE_WIN32_MAX_PATH+1)<0 ){
+      winLogError(SQLITE_CANTOPEN_FULLPATH, (DWORD)errno, "cygwin_conv_path",
+                  zRelative);
+      return SQLITE_CANTOPEN_FULLPATH;
+    }
     sqlite3_snprintf(MIN(nFull, pVfs->mxPathname), zFull, "%s\\%s",
                      sqlite3_data_directory, zOut);
   }else{
-    /*
-    ** NOTE: The Cygwin docs state that the maximum length needed
-    **       for the buffer passed to cygwin_conv_to_full_win32_path
-    **       is MAX_PATH.
-    */
-    cygwin_conv_to_full_win32_path(zRelative, zFull);
+    if( cygwin_conv_path(CCP_POSIX_TO_WIN_A, zRelative, zFull, nFull)<0 ){
+      winLogError(SQLITE_CANTOPEN_FULLPATH, (DWORD)errno, "cygwin_conv_path",
+                  zRelative);
+      return SQLITE_CANTOPEN_FULLPATH;
+    }
   }
   return SQLITE_OK;
 #endif
@@ -36195,7 +35259,7 @@ static int winFullPathname(
 #endif
 
 #if !SQLITE_OS_WINCE && !SQLITE_OS_WINRT && !defined(__CYGWIN__)
-  int nByte;
+  DWORD nByte;
   void *zConverted;
   char *zOut;
 
@@ -36229,13 +35293,27 @@ static int winFullPathname(
   }
   if( isNT() ){
     LPWSTR zTemp;
-    nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0) + 3;
-    zTemp = sqlite3_malloc( nByte*sizeof(zTemp[0]) );
+    nByte = osGetFullPathNameW((LPCWSTR)zConverted, 0, 0, 0);
+    if( nByte==0 ){
+      winLogError(SQLITE_ERROR, osGetLastError(),
+                  "GetFullPathNameW1", zConverted);
+      sqlite3_free(zConverted);
+      return SQLITE_CANTOPEN_FULLPATH;
+    }
+    nByte += 3;
+    zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
     if( zTemp==0 ){
       sqlite3_free(zConverted);
       return SQLITE_IOERR_NOMEM;
     }
-    osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
+    nByte = osGetFullPathNameW((LPCWSTR)zConverted, nByte, zTemp, 0);
+    if( nByte==0 ){
+      winLogError(SQLITE_ERROR, osGetLastError(),
+                  "GetFullPathNameW2", zConverted);
+      sqlite3_free(zConverted);
+      sqlite3_free(zTemp);
+      return SQLITE_CANTOPEN_FULLPATH;
+    }
     sqlite3_free(zConverted);
     zOut = unicodeToUtf8(zTemp);
     sqlite3_free(zTemp);
@@ -36243,13 +35321,27 @@ static int winFullPathname(
 #ifdef SQLITE_WIN32_HAS_ANSI
   else{
     char *zTemp;
-    nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0) + 3;
-    zTemp = sqlite3_malloc( nByte*sizeof(zTemp[0]) );
+    nByte = osGetFullPathNameA((char*)zConverted, 0, 0, 0);
+    if( nByte==0 ){
+      winLogError(SQLITE_ERROR, osGetLastError(),
+                  "GetFullPathNameA1", zConverted);
+      sqlite3_free(zConverted);
+      return SQLITE_CANTOPEN_FULLPATH;
+    }
+    nByte += 3;
+    zTemp = sqlite3MallocZero( nByte*sizeof(zTemp[0]) );
     if( zTemp==0 ){
       sqlite3_free(zConverted);
       return SQLITE_IOERR_NOMEM;
     }
-    osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
+    nByte = osGetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
+    if( nByte==0 ){
+      winLogError(SQLITE_ERROR, osGetLastError(),
+                  "GetFullPathNameA2", zConverted);
+      sqlite3_free(zConverted);
+      sqlite3_free(zTemp);
+      return SQLITE_CANTOPEN_FULLPATH;
+    }
     sqlite3_free(zConverted);
     zOut = sqlite3_win32_mbcs_to_utf8(zTemp);
     sqlite3_free(zTemp);
@@ -36300,9 +35392,9 @@ static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
   UNUSED_PARAMETER(pVfs);
   getLastErrorMsg(osGetLastError(), nBuf, zBufOut);
 }
-static void (*winDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol))(void){
+static void (*winDlSym(sqlite3_vfs *pVfs,void *pH,const char *zSym))(void){
   UNUSED_PARAMETER(pVfs);
-  return (void(*)(void))osGetProcAddressA((HANDLE)pHandle, zSymbol);
+  return (void(*)(void))osGetProcAddressA((HANDLE)pH, zSym);
 }
 static void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
   UNUSED_PARAMETER(pVfs);
@@ -36400,7 +35492,8 @@ static int winCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
 #endif
   /* 2^32 - to avoid use of LL and warnings in gcc */
   static const sqlite3_int64 max32BitValue = 
-      (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 + (sqlite3_int64)294967296;
+      (sqlite3_int64)2000000000 + (sqlite3_int64)2000000000 +
+      (sqlite3_int64)294967296;
 
 #if SQLITE_OS_WINCE
   SYSTEMTIME time;
@@ -36483,7 +35576,7 @@ SQLITE_API int sqlite3_os_init(void){
   static sqlite3_vfs winVfs = {
     3,                   /* iVersion */
     sizeof(winFile),     /* szOsFile */
-    MAX_PATH,            /* mxPathname */
+    SQLITE_WIN32_MAX_PATH, /* mxPathname */
     0,                   /* pNext */
     "win32",             /* zName */
     0,                   /* pAppData */
@@ -36507,9 +35600,8 @@ SQLITE_API int sqlite3_os_init(void){
 
   /* Double-check that the aSyscall[] array has been constructed
   ** correctly.  See ticket [bb3a86e890c8e96ab] */
-  assert( ArraySize(aSyscall)==73 );
+  assert( ArraySize(aSyscall)==74 );
 
-#ifndef SQLITE_OMIT_WAL
   /* get memory map allocation granularity */
   memset(&winSysInfo, 0, sizeof(SYSTEM_INFO));
 #if SQLITE_OS_WINRT
@@ -36517,8 +35609,8 @@ SQLITE_API int sqlite3_os_init(void){
 #else
   osGetSystemInfo(&winSysInfo);
 #endif
-  assert(winSysInfo.dwAllocationGranularity > 0);
-#endif
+  assert( winSysInfo.dwAllocationGranularity>0 );
+  assert( winSysInfo.dwPageSize>0 );
 
   sqlite3_vfs_register(&winVfs, 1);
   return SQLITE_OK; 
@@ -36526,7 +35618,7 @@ SQLITE_API int sqlite3_os_init(void){
 
 SQLITE_API int sqlite3_os_end(void){ 
 #if SQLITE_OS_WINRT
-  if( sleepObj != NULL ){
+  if( sleepObj!=NULL ){
     osCloseHandle(sleepObj);
     sleepObj = NULL;
   }
@@ -36611,7 +35703,7 @@ SQLITE_API int sqlite3_os_end(void){
 /*
 ** A bitmap is an instance of the following structure.
 **
-** This bitmap records the existance of zero or more bits
+** This bitmap records the existence of zero or more bits
 ** with values between 1 and iSize, inclusive.
 **
 ** There are three possible representations of the bitmap.
@@ -36879,10 +35971,9 @@ SQLITE_PRIVATE int sqlite3BitvecBuiltinTest(int sz, int *aOp){
   /* Allocate the Bitvec to be tested and a linear array of
   ** bits to act as the reference */
   pBitvec = sqlite3BitvecCreate( sz );
-  pV = sqlite3_malloc( (sz+7)/8 + 1 );
+  pV = sqlite3MallocZero( (sz+7)/8 + 1 );
   pTmpSpace = sqlite3_malloc(BITVEC_SZ);
   if( pBitvec==0 || pV==0 || pTmpSpace==0  ) goto bitvec_end;
-  memset(pV, 0, (sz+7)/8 + 1);
 
   /* NULL pBitvec tests */
   sqlite3BitvecSet(0, 1);
@@ -37966,11 +37057,10 @@ static int pcache1ResizeHash(PCache1 *p){
 
   pcache1LeaveMutex(p->pGroup);
   if( p->nHash ){ sqlite3BeginBenignMalloc(); }
-  apNew = (PgHdr1 **)sqlite3_malloc(sizeof(PgHdr1 *)*nNew);
+  apNew = (PgHdr1 **)sqlite3MallocZero(sizeof(PgHdr1 *)*nNew);
   if( p->nHash ){ sqlite3EndBenignMalloc(); }
   pcache1EnterMutex(p->pGroup);
   if( apNew ){
-    memset(apNew, 0, sizeof(PgHdr1 *)*nNew);
     for(i=0; i<p->nHash; i++){
       PgHdr1 *pPage;
       PgHdr1 *pNext = p->apHash[i];
@@ -38133,7 +37223,7 @@ static sqlite3_pcache *pcache1Create(int szPage, int szExtra, int bPurgeable){
   int sz;               /* Bytes of memory required to allocate the new cache */
 
   /*
-  ** The seperateCache variable is true if each PCache has its own private
+  ** The separateCache variable is true if each PCache has its own private
   ** PGroup.  In other words, separateCache is true for mode (1) where no
   ** mutexing is required.
   **
@@ -38154,9 +37244,8 @@ static sqlite3_pcache *pcache1Create(int szPage, int szExtra, int bPurgeable){
   assert( szExtra < 300 );
 
   sz = sizeof(PCache1) + sizeof(PGroup)*separateCache;
-  pCache = (PCache1 *)sqlite3_malloc(sz);
+  pCache = (PCache1 *)sqlite3MallocZero(sz);
   if( pCache ){
-    memset(pCache, 0, sz);
     if( separateCache ){
       pGroup = (PGroup*)&pCache[1];
       pGroup->mxPinned = 10;
@@ -38337,6 +37426,7 @@ static sqlite3_pcache_page *pcache1Fetch(
   if( pCache->nPage>=pCache->nHash && pcache1ResizeHash(pCache) ){
     goto fetch_out;
   }
+  assert( pCache->nHash>0 && pCache->apHash );
 
   /* Step 4. Try to recycle a page. */
   if( pCache->bPurgeable && pGroup->pLruTail && (
@@ -39034,7 +38124,7 @@ SQLITE_PRIVATE int sqlite3RowSetNext(RowSet *p, i64 *pRowid){
 }
 
 /*
-** Check to see if element iRowid was inserted into the the rowset as
+** Check to see if element iRowid was inserted into the rowset as
 ** part of any insert batch prior to iBatch.  Return 1 or 0.
 **
 ** If this is the first test of a new batch and if there exist entires
@@ -39158,7 +38248,6 @@ SQLITE_PRIVATE int sqlite3RowSetTest(RowSet *pRowSet, u8 iBatch, sqlite3_int64 i
 # define sqlite3WalClose(w,x,y,z)                0
 # define sqlite3WalBeginReadTransaction(y,z)     0
 # define sqlite3WalEndReadTransaction(z)
-# define sqlite3WalRead(v,w,x,y,z)               0
 # define sqlite3WalDbsize(y)                     0
 # define sqlite3WalBeginWriteTransaction(y)      0
 # define sqlite3WalEndWriteTransaction(x)        0
@@ -39171,6 +38260,7 @@ SQLITE_PRIVATE int sqlite3RowSetTest(RowSet *pRowSet, u8 iBatch, sqlite3_int64 i
 # define sqlite3WalExclusiveMode(y,z)            0
 # define sqlite3WalHeapMemory(z)                 0
 # define sqlite3WalFramesize(z)                  0
+# define sqlite3WalFindFrame(x,y,z)              0
 #else
 
 #define WAL_SAVEPOINT_NDATA 4
@@ -39198,7 +38288,8 @@ SQLITE_PRIVATE int sqlite3WalBeginReadTransaction(Wal *pWal, int *);
 SQLITE_PRIVATE void sqlite3WalEndReadTransaction(Wal *pWal);
 
 /* Read a page from the write-ahead log, if it is present. */
-SQLITE_PRIVATE int sqlite3WalRead(Wal *pWal, Pgno pgno, int *pInWal, int nOut, u8 *pOut);
+SQLITE_PRIVATE int sqlite3WalFindFrame(Wal *, Pgno, u32 *);
+SQLITE_PRIVATE int sqlite3WalReadFrame(Wal *, u32, int, u8 *);
 
 /* If the WAL is not empty, return the size of the database. */
 SQLITE_PRIVATE Pgno sqlite3WalDbsize(Wal *pWal);
@@ -39318,7 +38409,7 @@ SQLITE_PRIVATE int sqlite3WalFramesize(Wal *pWal);
 ** 
 ** Definition: Two databases (or the same database at two points it time)
 ** are said to be "logically equivalent" if they give the same answer to
-** all queries.  Note in particular the the content of freelist leaf
+** all queries.  Note in particular the content of freelist leaf
 ** pages can be changed arbitarily without effecting the logical equivalence
 ** of the database.
 ** 
@@ -39516,7 +38607,7 @@ int sqlite3PagerTrace=1;  /* True to enable tracing */
 **    * A write transaction is active.
 **    * An EXCLUSIVE or greater lock is held on the database file.
 **    * All writing and syncing of journal and database data has finished.
-**      If no error occured, all that remains is to finalize the journal to
+**      If no error occurred, all that remains is to finalize the journal to
 **      commit the transaction. If an error did occur, the caller will need
 **      to rollback the transaction. 
 **
@@ -39696,6 +38787,13 @@ struct PagerSavepoint {
 #endif
 };
 
+/*
+** Bits of the Pager.doNotSpill flag.  See further description below.
+*/
+#define SPILLFLAG_OFF         0x01      /* Never spill cache.  Set via pragma */
+#define SPILLFLAG_ROLLBACK    0x02      /* Current rolling back, so do not spill */
+#define SPILLFLAG_NOSYNC      0x04      /* Spill is ok, but do not sync */
+
 /*
 ** A open page cache is an instance of struct Pager. A description of
 ** some of the more important member variables follows:
@@ -39762,19 +38860,21 @@ struct PagerSavepoint {
 **   journal file from being successfully finalized, the setMaster flag
 **   is cleared anyway (and the pager will move to ERROR state).
 **
-** doNotSpill, doNotSyncSpill
+** doNotSpill
 **
-**   These two boolean variables control the behaviour of cache-spills
-**   (calls made by the pcache module to the pagerStress() routine to
-**   write cached data to the file-system in order to free up memory).
+**   This variables control the behavior of cache-spills  (calls made by
+**   the pcache module to the pagerStress() routine to write cached data
+**   to the file-system in order to free up memory).
 **
-**   When doNotSpill is non-zero, writing to the database from pagerStress()
-**   is disabled altogether. This is done in a very obscure case that
+**   When bits SPILLFLAG_OFF or SPILLFLAG_ROLLBACK of doNotSpill are set,
+**   writing to the database from pagerStress() is disabled altogether.
+**   The SPILLFLAG_ROLLBACK case is done in a very obscure case that
 **   comes up during savepoint rollback that requires the pcache module
 **   to allocate a new page to prevent the journal file from being written
-**   while it is being traversed by code in pager_playback().
+**   while it is being traversed by code in pager_playback().  The SPILLFLAG_OFF
+**   case is a user preference.
 ** 
-**   If doNotSyncSpill is non-zero, writing to the database from pagerStress()
+**   If the SPILLFLAG_NOSYNC bit is set, writing to the database from pagerStress()
 **   is permitted, but syncing the journal file is not. This flag is set
 **   by sqlite3PagerWrite() when the file-system sector-size is larger than
 **   the database page-size in order to prevent a journal sync from happening 
@@ -39878,7 +38978,6 @@ struct Pager {
   u8 changeCountDone;         /* Set after incrementing the change-counter */
   u8 setMaster;               /* True if a m-j name has been written to jrnl */
   u8 doNotSpill;              /* Do not spill the cache when non-zero */
-  u8 doNotSyncSpill;          /* Do not do a spill that requires jrnl sync */
   u8 subjInMemory;            /* True to use in-memory sub-journals */
   Pgno dbSize;                /* Number of pages in the database */
   Pgno dbOrigSize;            /* dbSize before the current transaction */
@@ -39898,6 +38997,11 @@ struct Pager {
   PagerSavepoint *aSavepoint; /* Array of active savepoints */
   int nSavepoint;             /* Number of elements in aSavepoint[] */
   char dbFileVers[16];        /* Changes whenever database file changes */
+
+  u8 bUseFetch;               /* True to use xFetch() */
+  int nMmapOut;               /* Number of mmap pages currently outstanding */
+  sqlite3_int64 szMmap;       /* Desired maximum mmap size */
+  PgHdr *pMmapFreelist;       /* List of free mmap page headers (pDirty) */
   /*
   ** End of the routinely-changing class members
   ***************************************************************************/
@@ -40008,6 +39112,16 @@ static const unsigned char aJournalMagic[] = {
 # define MEMDB pPager->memDb
 #endif
 
+/*
+** The macro USEFETCH is true if we are allowed to use the xFetch and xUnfetch
+** interfaces to access the database using memory-mapped I/O.
+*/
+#if SQLITE_MAX_MMAP_SIZE>0
+# define USEFETCH(x) ((x)->bUseFetch)
+#else
+# define USEFETCH(x) 0
+#endif
+
 /*
 ** The maximum legal page number is (2^31 - 1).
 */
@@ -40242,13 +39356,17 @@ static char *print_pager_state(Pager *p){
 **     PagerSavepoint.pInSavepoint.
 */
 static int subjRequiresPage(PgHdr *pPg){
-  Pgno pgno = pPg->pgno;
   Pager *pPager = pPg->pPager;
+  PagerSavepoint *p;
+  Pgno pgno;
   int i;
-  for(i=0; i<pPager->nSavepoint; i++){
-    PagerSavepoint *p = &pPager->aSavepoint[i];
-    if( p->nOrig>=pgno && 0==sqlite3BitvecTest(p->pInSavepoint, pgno) ){
-      return 1;
+  if( pPager->nSavepoint ){
+    pgno = pPg->pgno;
+    for(i=0; i<pPager->nSavepoint; i++){
+      p = &pPager->aSavepoint[i];
+      if( p->nOrig>=pgno && 0==sqlite3BitvecTest(p->pInSavepoint, pgno) ){
+        return 1;
+      }
     }
   }
   return 0;
@@ -40642,7 +39760,7 @@ static int writeJournalHdr(Pager *pPager){
     memset(zHeader, 0, sizeof(aJournalMagic)+4);
   }
 
-  /* The random check-hash initialiser */ 
+  /* The random check-hash initializer */ 
   sqlite3_randomness(sizeof(pPager->cksumInit), &pPager->cksumInit);
   put32bits(&zHeader[sizeof(aJournalMagic)+4], pPager->cksumInit);
   /* The initial database size */
@@ -41040,6 +40158,7 @@ static void pager_unlock(Pager *pPager){
     pPager->changeCountDone = pPager->tempFile;
     pPager->eState = PAGER_OPEN;
     pPager->errCode = SQLITE_OK;
+    if( USEFETCH(pPager) ) sqlite3OsUnfetch(pPager->fd, 0, 0);
   }
 
   pPager->journalOff = 0;
@@ -41081,6 +40200,8 @@ static int pager_error(Pager *pPager, int rc){
   return rc;
 }
 
+static int pager_truncate(Pager *pPager, Pgno nPage);
+
 /*
 ** This routine ends a transaction. A transaction is usually ended by 
 ** either a COMMIT or a ROLLBACK operation. This routine may be called 
@@ -41134,7 +40255,7 @@ static int pager_error(Pager *pPager, int rc){
 ** to the first error encountered (the journal finalization one) is
 ** returned.
 */
-static int pager_end_transaction(Pager *pPager, int hasMaster){
+static int pager_end_transaction(Pager *pPager, int hasMaster, int bCommit){
   int rc = SQLITE_OK;      /* Error code from journal finalization operation */
   int rc2 = SQLITE_OK;     /* Error code from db file unlock operation */
 
@@ -41184,12 +40305,13 @@ static int pager_end_transaction(Pager *pPager, int hasMaster){
       ** file should be closed and deleted. If this connection writes to
       ** the database file, it will do so using an in-memory journal. 
       */
+      int bDelete = (!pPager->tempFile && sqlite3JournalExists(pPager->jfd));
       assert( pPager->journalMode==PAGER_JOURNALMODE_DELETE 
            || pPager->journalMode==PAGER_JOURNALMODE_MEMORY 
            || pPager->journalMode==PAGER_JOURNALMODE_WAL 
       );
       sqlite3OsClose(pPager->jfd);
-      if( !pPager->tempFile ){
+      if( bDelete ){
         rc = sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
       }
     }
@@ -41219,7 +40341,17 @@ static int pager_end_transaction(Pager *pPager, int hasMaster){
     */
     rc2 = sqlite3WalEndWriteTransaction(pPager->pWal);
     assert( rc2==SQLITE_OK );
+  }else if( rc==SQLITE_OK && bCommit && pPager->dbFileSize>pPager->dbSize ){
+    /* This branch is taken when committing a transaction in rollback-journal
+    ** mode if the database file on disk is larger than the database image.
+    ** At this point the journal has been finalized and the transaction 
+    ** successfully committed, but the EXCLUSIVE lock is still held on the
+    ** file. So it is safe to truncate the database file to its minimum
+    ** required size.  */
+    assert( pPager->eLock==EXCLUSIVE_LOCK );
+    rc = pager_truncate(pPager, pPager->dbSize);
   }
+
   if( !pPager->exclusiveMode 
    && (!pagerUseWal(pPager) || sqlite3WalExclusiveMode(pPager->pWal, 0))
   ){
@@ -41258,7 +40390,7 @@ static void pagerUnlockAndRollback(Pager *pPager){
       sqlite3EndBenignMalloc();
     }else if( !pPager->exclusiveMode ){
       assert( pPager->eState==PAGER_READER );
-      pager_end_transaction(pPager, 0);
+      pager_end_transaction(pPager, 0, 0);
     }
   }
   pager_unlock(pPager);
@@ -41482,7 +40614,7 @@ static int pager_playback_one_page(
     i64 ofst = (pgno-1)*(i64)pPager->pageSize;
     testcase( !isSavepnt && pPg!=0 && (pPg->flags&PGHDR_NEED_SYNC)!=0 );
     assert( !pagerUseWal(pPager) );
-    rc = sqlite3OsWrite(pPager->fd, (u8*)aData, pPager->pageSize, ofst);
+    rc = sqlite3OsWrite(pPager->fd, (u8 *)aData, pPager->pageSize, ofst);
     if( pgno>pPager->dbFileSize ){
       pPager->dbFileSize = pgno;
     }
@@ -41509,11 +40641,11 @@ static int pager_playback_one_page(
     ** requiring a journal-sync before it is written.
     */
     assert( isSavepnt );
-    assert( pPager->doNotSpill==0 );
-    pPager->doNotSpill++;
+    assert( (pPager->doNotSpill & SPILLFLAG_ROLLBACK)==0 );
+    pPager->doNotSpill |= SPILLFLAG_ROLLBACK;
     rc = sqlite3PagerAcquire(pPager, pgno, &pPg, 1);
-    assert( pPager->doNotSpill==1 );
-    pPager->doNotSpill--;
+    assert( (pPager->doNotSpill & SPILLFLAG_ROLLBACK)!=0 );
+    pPager->doNotSpill &= ~SPILLFLAG_ROLLBACK;
     if( rc!=SQLITE_OK ) return rc;
     pPg->flags &= ~PGHDR_NEED_READ;
     sqlite3PcacheMakeDirty(pPg);
@@ -41752,6 +40884,21 @@ static int pager_truncate(Pager *pPager, Pgno nPage){
   return rc;
 }
 
+/*
+** Return a sanitized version of the sector-size of OS file pFile. The
+** return value is guaranteed to lie between 32 and MAX_SECTOR_SIZE.
+*/
+SQLITE_PRIVATE int sqlite3SectorSize(sqlite3_file *pFile){
+  int iRet = sqlite3OsSectorSize(pFile);
+  if( iRet<32 ){
+    iRet = 512;
+  }else if( iRet>MAX_SECTOR_SIZE ){
+    assert( MAX_SECTOR_SIZE>=512 );
+    iRet = MAX_SECTOR_SIZE;
+  }
+  return iRet;
+}
+
 /*
 ** Set the value of the Pager.sectorSize variable for the given
 ** pager based on the value returned by the xSectorSize method
@@ -41787,14 +40934,7 @@ static void setSectorSize(Pager *pPager){
     ** call will segfault. */
     pPager->sectorSize = 512;
   }else{
-    pPager->sectorSize = sqlite3OsSectorSize(pPager->fd);
-    if( pPager->sectorSize<32 ){
-      pPager->sectorSize = 512;
-    }
-    if( pPager->sectorSize>MAX_SECTOR_SIZE ){
-      assert( MAX_SECTOR_SIZE>=512 );
-      pPager->sectorSize = MAX_SECTOR_SIZE;
-    }
+    pPager->sectorSize = sqlite3SectorSize(pPager->fd);
   }
 }
 
@@ -41865,6 +41005,7 @@ static int pager_playback(Pager *pPager, int isHot){
   int res = 1;             /* Value returned by sqlite3OsAccess() */
   char *zMaster = 0;       /* Name of master journal file if any */
   int needPagerReset;      /* True to reset page prior to first page rollback */
+  int nPlayback = 0;       /* Total number of pages restored from journal */
 
   /* Figure out how many records are in the journal.  Abort early if
   ** the journal is empty.
@@ -41965,7 +41106,9 @@ static int pager_playback(Pager *pPager, int isHot){
         needPagerReset = 0;
       }
       rc = pager_playback_one_page(pPager,&pPager->journalOff,0,1,0);
-      if( rc!=SQLITE_OK ){
+      if( rc==SQLITE_OK ){
+        nPlayback++;
+      }else{
         if( rc==SQLITE_DONE ){
           pPager->journalOff = szJ;
           break;
@@ -42025,7 +41168,7 @@ end_playback:
     rc = sqlite3PagerSync(pPager);
   }
   if( rc==SQLITE_OK ){
-    rc = pager_end_transaction(pPager, zMaster[0]!='\0');
+    rc = pager_end_transaction(pPager, zMaster[0]!='\0', 0);
     testcase( rc!=SQLITE_OK );
   }
   if( rc==SQLITE_OK && zMaster[0] && res ){
@@ -42035,6 +41178,10 @@ end_playback:
     rc = pager_delmaster(pPager, zMaster);
     testcase( rc!=SQLITE_OK );
   }
+  if( isHot && nPlayback ){
+    sqlite3_log(SQLITE_NOTICE_RECOVER_ROLLBACK, "recovered %d pages from %s",
+                nPlayback, pPager->zJournal);
+  }
 
   /* The Pager.sectorSize variable may have been updated while rolling
   ** back a journal created by a process with a different sector size
@@ -42056,27 +41203,22 @@ end_playback:
 ** If an IO error occurs, then the IO error is returned to the caller.
 ** Otherwise, SQLITE_OK is returned.
 */
-static int readDbPage(PgHdr *pPg){
+static int readDbPage(PgHdr *pPg, u32 iFrame){
   Pager *pPager = pPg->pPager; /* Pager object associated with page pPg */
   Pgno pgno = pPg->pgno;       /* Page number to read */
   int rc = SQLITE_OK;          /* Return code */
-  int isInWal = 0;             /* True if page is in log file */
   int pgsz = pPager->pageSize; /* Number of bytes to read */
 
   assert( pPager->eState>=PAGER_READER && !MEMDB );
   assert( isOpen(pPager->fd) );
 
-  if( NEVER(!isOpen(pPager->fd)) ){
-    assert( pPager->tempFile );
-    memset(pPg->pData, 0, pPager->pageSize);
-    return SQLITE_OK;
-  }
-
-  if( pagerUseWal(pPager) ){
+#ifndef SQLITE_OMIT_WAL
+  if( iFrame ){
     /* Try to pull the page from the write-ahead log. */
-    rc = sqlite3WalRead(pPager->pWal, pgno, &isInWal, pgsz, pPg->pData);
-  }
-  if( rc==SQLITE_OK && !isInWal ){
+    rc = sqlite3WalReadFrame(pPager->pWal, iFrame, pgsz, pPg->pData);
+  }else
+#endif
+  {
     i64 iOffset = (pgno-1)*(i64)pPager->pageSize;
     rc = sqlite3OsRead(pPager->fd, pPg->pData, pgsz, iOffset);
     if( rc==SQLITE_IOERR_SHORT_READ ){
@@ -42155,12 +41297,17 @@ static int pagerUndoCallback(void *pCtx, Pgno iPg){
   Pager *pPager = (Pager *)pCtx;
   PgHdr *pPg;
 
+  assert( pagerUseWal(pPager) );
   pPg = sqlite3PagerLookup(pPager, iPg);
   if( pPg ){
     if( sqlite3PcachePageRefcount(pPg)==1 ){
       sqlite3PcacheDrop(pPg);
     }else{
-      rc = readDbPage(pPg);
+      u32 iFrame = 0;
+      rc = sqlite3WalFindFrame(pPager->pWal, pPg->pgno, &iFrame);
+      if( rc==SQLITE_OK ){
+        rc = readDbPage(pPg, iFrame);
+      }
       if( rc==SQLITE_OK ){
         pPager->xReiniter(pPg);
       }
@@ -42304,6 +41451,7 @@ static int pagerBeginReadTransaction(Pager *pPager){
   rc = sqlite3WalBeginReadTransaction(pPager->pWal, &changed);
   if( rc!=SQLITE_OK || changed ){
     pager_reset(pPager);
+    if( USEFETCH(pPager) ) sqlite3OsUnfetch(pPager->fd, 0, 0);
   }
 
   return rc;
@@ -42394,6 +41542,7 @@ static int pagerOpenWalIfPresent(Pager *pPager){
     if( rc ) return rc;
     if( nPage==0 ){
       rc = sqlite3OsDelete(pPager->pVfs, pPager->zWal, 0);
+      if( rc==SQLITE_IOERR_DELETE_NOENT ) rc = SQLITE_OK;
       isWal = 0;
     }else{
       rc = sqlite3OsAccess(
@@ -42564,6 +41713,29 @@ SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager *pPager, int mxPage){
   sqlite3PcacheSetCachesize(pPager->pPCache, mxPage);
 }
 
+/*
+** Invoke SQLITE_FCNTL_MMAP_SIZE based on the current value of szMmap.
+*/
+static void pagerFixMaplimit(Pager *pPager){
+#if SQLITE_MAX_MMAP_SIZE>0
+  sqlite3_file *fd = pPager->fd;
+  if( isOpen(fd) && fd->pMethods->iVersion>=3 ){
+    sqlite3_int64 sz;
+    sz = pPager->szMmap;
+    pPager->bUseFetch = (sz>0);
+    sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_MMAP_SIZE, &sz);
+  }
+#endif
+}
+
+/*
+** Change the maximum size of any memory mapping made of the database file.
+*/
+SQLITE_PRIVATE void sqlite3PagerSetMmapLimit(Pager *pPager, sqlite3_int64 szMmap){
+  pPager->szMmap = szMmap;
+  pagerFixMaplimit(pPager);
+}
+
 /*
 ** Free as much memory as possible from the pager.
 */
@@ -42572,9 +41744,12 @@ SQLITE_PRIVATE void sqlite3PagerShrink(Pager *pPager){
 }
 
 /*
-** Adjust the robustness of the database to damage due to OS crashes
-** or power failures by changing the number of syncs()s when writing
-** the rollback journal.  There are three levels:
+** Adjust settings of the pager to those specified in the pgFlags parameter.
+**
+** The "level" in pgFlags & PAGER_SYNCHRONOUS_MASK sets the robustness
+** of the database to damage due to OS crashes or power failures by
+** changing the number of syncs()s when writing the journals.
+** There are three levels:
 **
 **    OFF       sqlite3OsSync() is never called.  This is the default
 **              for temporary and transient files.
@@ -42615,22 +41790,21 @@ SQLITE_PRIVATE void sqlite3PagerShrink(Pager *pPager){
 ** and FULL=3.
 */
 #ifndef SQLITE_OMIT_PAGER_PRAGMAS
-SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(
+SQLITE_PRIVATE void sqlite3PagerSetFlags(
   Pager *pPager,        /* The pager to set safety level for */
-  int level,            /* PRAGMA synchronous.  1=OFF, 2=NORMAL, 3=FULL */  
-  int bFullFsync,       /* PRAGMA fullfsync */
-  int bCkptFullFsync    /* PRAGMA checkpoint_fullfsync */
+  unsigned pgFlags      /* Various flags */
 ){
+  unsigned level = pgFlags & PAGER_SYNCHRONOUS_MASK;
   assert( level>=1 && level<=3 );
   pPager->noSync =  (level==1 || pPager->tempFile) ?1:0;
   pPager->fullSync = (level==3 && !pPager->tempFile) ?1:0;
   if( pPager->noSync ){
     pPager->syncFlags = 0;
     pPager->ckptSyncFlags = 0;
-  }else if( bFullFsync ){
+  }else if( pgFlags & PAGER_FULLFSYNC ){
     pPager->syncFlags = SQLITE_SYNC_FULL;
     pPager->ckptSyncFlags = SQLITE_SYNC_FULL;
-  }else if( bCkptFullFsync ){
+  }else if( pgFlags & PAGER_CKPT_FULLFSYNC ){
     pPager->syncFlags = SQLITE_SYNC_NORMAL;
     pPager->ckptSyncFlags = SQLITE_SYNC_FULL;
   }else{
@@ -42641,6 +41815,11 @@ SQLITE_PRIVATE void sqlite3PagerSetSafetyLevel(
   if( pPager->fullSync ){
     pPager->walSyncFlags |= WAL_SYNC_TRANSACTIONS;
   }
+  if( pgFlags & PAGER_CACHESPILL ){
+    pPager->doNotSpill &= ~SPILLFLAG_OFF;
+  }else{
+    pPager->doNotSpill |= SPILLFLAG_OFF;
+  }
 }
 #endif
 
@@ -42711,9 +41890,16 @@ SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(
   Pager *pPager,                       /* Pager object */
   int (*xBusyHandler)(void *),         /* Pointer to busy-handler function */
   void *pBusyHandlerArg                /* Argument to pass to xBusyHandler */
-){  
+){
   pPager->xBusyHandler = xBusyHandler;
   pPager->pBusyHandlerArg = pBusyHandlerArg;
+
+  if( isOpen(pPager->fd) ){
+    void **ap = (void **)&pPager->xBusyHandler;
+    assert( ((int(*)(void *))(ap[0]))==xBusyHandler );
+    assert( ap[1]==pBusyHandlerArg );
+    sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_BUSYHANDLER, (void *)ap);
+  }
 }
 
 /*
@@ -42792,6 +41978,7 @@ SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager *pPager, u32 *pPageSize, int nR
     assert( nReserve>=0 && nReserve<1000 );
     pPager->nReserve = (i16)nReserve;
     pagerReportSize(pPager);
+    pagerFixMaplimit(pPager);
   }
   return rc;
 }
@@ -42945,7 +42132,7 @@ static int pager_wait_on_lock(Pager *pPager, int locktype){
 ** dirty page were to be discarded from the cache via the pagerStress()
 ** routine, pagerStress() would not write the current page content to
 ** the database file. If a savepoint transaction were rolled back after
-** this happened, the correct behaviour would be to restore the current
+** this happened, the correct behavior would be to restore the current
 ** content of the page. However, since this content is not present in either
 ** the database file or the portion of the rollback journal and 
 ** sub-journal rolled back the content could not be restored and the
@@ -42969,12 +42156,26 @@ static void assertTruncateConstraint(Pager *pPager){
 ** function does not actually modify the database file on disk. It 
 ** just sets the internal state of the pager object so that the 
 ** truncation will be done when the current transaction is committed.
+**
+** This function is only called right before committing a transaction.
+** Once this function has been called, the transaction must either be
+** rolled back or committed. It is not safe to call this function and
+** then continue writing to the database.
 */
 SQLITE_PRIVATE void sqlite3PagerTruncateImage(Pager *pPager, Pgno nPage){
   assert( pPager->dbSize>=nPage );
   assert( pPager->eState>=PAGER_WRITER_CACHEMOD );
   pPager->dbSize = nPage;
-  assertTruncateConstraint(pPager);
+
+  /* At one point the code here called assertTruncateConstraint() to
+  ** ensure that all pages being truncated away by this operation are,
+  ** if one or more savepoints are open, present in the savepoint 
+  ** journal so that they can be restored if the savepoint is rolled
+  ** back. This is no longer necessary as this function is now only
+  ** called right before committing a transaction. So although the 
+  ** Pager object may still have open savepoints (Pager.nSavepoint!=0), 
+  ** they cannot be rolled back. So the assertTruncateConstraint() call
+  ** is no longer correct. */
 }
 
 
@@ -43003,6 +42204,81 @@ static int pagerSyncHotJournal(Pager *pPager){
   return rc;
 }
 
+/*
+** Obtain a reference to a memory mapped page object for page number pgno. 
+** The new object will use the pointer pData, obtained from xFetch().
+** If successful, set *ppPage to point to the new page reference
+** and return SQLITE_OK. Otherwise, return an SQLite error code and set
+** *ppPage to zero.
+**
+** Page references obtained by calling this function should be released
+** by calling pagerReleaseMapPage().
+*/
+static int pagerAcquireMapPage(
+  Pager *pPager,                  /* Pager object */
+  Pgno pgno,                      /* Page number */
+  void *pData,                    /* xFetch()'d data for this page */
+  PgHdr **ppPage                  /* OUT: Acquired page object */
+){
+  PgHdr *p;                       /* Memory mapped page to return */
+
+  if( pPager->pMmapFreelist ){
+    *ppPage = p = pPager->pMmapFreelist;
+    pPager->pMmapFreelist = p->pDirty;
+    p->pDirty = 0;
+    memset(p->pExtra, 0, pPager->nExtra);
+  }else{
+    *ppPage = p = (PgHdr *)sqlite3MallocZero(sizeof(PgHdr) + pPager->nExtra);
+    if( p==0 ){
+      sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1) * pPager->pageSize, pData);
+      return SQLITE_NOMEM;
+    }
+    p->pExtra = (void *)&p[1];
+    p->flags = PGHDR_MMAP;
+    p->nRef = 1;
+    p->pPager = pPager;
+  }
+
+  assert( p->pExtra==(void *)&p[1] );
+  assert( p->pPage==0 );
+  assert( p->flags==PGHDR_MMAP );
+  assert( p->pPager==pPager );
+  assert( p->nRef==1 );
+
+  p->pgno = pgno;
+  p->pData = pData;
+  pPager->nMmapOut++;
+
+  return SQLITE_OK;
+}
+
+/*
+** Release a reference to page pPg. pPg must have been returned by an 
+** earlier call to pagerAcquireMapPage().
+*/
+static void pagerReleaseMapPage(PgHdr *pPg){
+  Pager *pPager = pPg->pPager;
+  pPager->nMmapOut--;
+  pPg->pDirty = pPager->pMmapFreelist;
+  pPager->pMmapFreelist = pPg;
+
+  assert( pPager->fd->pMethods->iVersion>=3 );
+  sqlite3OsUnfetch(pPager->fd, (i64)(pPg->pgno-1)*pPager->pageSize, pPg->pData);
+}
+
+/*
+** Free all PgHdr objects stored in the Pager.pMmapFreelist list.
+*/
+static void pagerFreeMapHdrs(Pager *pPager){
+  PgHdr *p;
+  PgHdr *pNext;
+  for(p=pPager->pMmapFreelist; p; p=pNext){
+    pNext = p->pDirty;
+    sqlite3_free(p);
+  }
+}
+
+
 /*
 ** Shutdown the page cache.  Free all memory and close all files.
 **
@@ -43023,6 +42299,7 @@ SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager){
   assert( assert_pager_state(pPager) );
   disable_simulated_io_errors();
   sqlite3BeginBenignMalloc();
+  pagerFreeMapHdrs(pPager);
   /* pPager->errCode = 0; */
   pPager->exclusiveMode = 0;
 #ifndef SQLITE_OMIT_WAL
@@ -43092,7 +42369,7 @@ SQLITE_PRIVATE void sqlite3PagerRef(DbPage *pPg){
 **
 ** If the Pager.noSync flag is set, then this function is a no-op.
 ** Otherwise, the actions required depend on the journal-mode and the 
-** device characteristics of the the file-system, as follows:
+** device characteristics of the file-system, as follows:
 **
 **   * If the journal file is an in-memory journal file, no action need
 **     be taken.
@@ -43284,7 +42561,10 @@ static int pager_write_pagelist(Pager *pPager, PgHdr *pList){
   ** file size will be.
   */
   assert( rc!=SQLITE_OK || isOpen(pPager->fd) );
-  if( rc==SQLITE_OK && pPager->dbSize>pPager->dbHintSize ){
+  if( rc==SQLITE_OK 
+   && pPager->dbHintSize<pPager->dbSize
+   && (pList->pDirty || pList->pgno>pPager->dbHintSize)
+  ){
     sqlite3_int64 szFile = pPager->pageSize * (sqlite3_int64)pPager->dbSize;
     sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_SIZE_HINT, &szFile);
     pPager->dbHintSize = pPager->dbSize;
@@ -43440,13 +42720,14 @@ static int pagerStress(void *p, PgHdr *pPg){
   assert( pPg->pPager==pPager );
   assert( pPg->flags&PGHDR_DIRTY );
 
-  /* The doNotSyncSpill flag is set during times when doing a sync of
+  /* The doNotSpill NOSYNC bit is set during times when doing a sync of
   ** journal (and adding a new header) is not allowed.  This occurs
   ** during calls to sqlite3PagerWrite() while trying to journal multiple
   ** pages belonging to the same sector.
   **
-  ** The doNotSpill flag inhibits all cache spilling regardless of whether
-  ** or not a sync is required.  This is set during a rollback.
+  ** The doNotSpill ROLLBACK and OFF bits inhibits all cache spilling
+  ** regardless of whether or not a sync is required.  This is set during
+  ** a rollback or by user request, respectively.
   **
   ** Spilling is also prohibited when in an error state since that could
   ** lead to database corruption.   In the current implementaton it 
@@ -43456,8 +42737,13 @@ static int pagerStress(void *p, PgHdr *pPg){
   ** test for the error state as a safeguard against future changes.
   */
   if( NEVER(pPager->errCode) ) return SQLITE_OK;
-  if( pPager->doNotSpill ) return SQLITE_OK;
-  if( pPager->doNotSyncSpill && (pPg->flags & PGHDR_NEED_SYNC)!=0 ){
+  testcase( pPager->doNotSpill & SPILLFLAG_ROLLBACK );
+  testcase( pPager->doNotSpill & SPILLFLAG_OFF );
+  testcase( pPager->doNotSpill & SPILLFLAG_NOSYNC );
+  if( pPager->doNotSpill
+   && ((pPager->doNotSpill & (SPILLFLAG_ROLLBACK|SPILLFLAG_OFF))!=0
+      || (pPg->flags & PGHDR_NEED_SYNC)!=0)
+  ){
     return SQLITE_OK;
   }
 
@@ -43691,7 +42977,7 @@ SQLITE_PRIVATE int sqlite3PagerOpen(
     memcpy(pPager->zFilename, zPathname, nPathname);
     if( nUri ) memcpy(&pPager->zFilename[nPathname+1], zUri, nUri);
     memcpy(pPager->zJournal, zPathname, nPathname);
-    memcpy(&pPager->zJournal[nPathname], "-journal\000", 8+1);
+    memcpy(&pPager->zJournal[nPathname], "-journal\000", 8+2);
     sqlite3FileSuffix3(pPager->zFilename, pPager->zJournal);
 #ifndef SQLITE_OMIT_WAL
     pPager->zWal = &pPager->zJournal[nPathname+8+1];
@@ -43838,6 +43124,7 @@ SQLITE_PRIVATE int sqlite3PagerOpen(
   /* pPager->pBusyHandlerArg = 0; */
   pPager->xReiniter = xReinit;
   /* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */
+  /* pPager->szMmap = SQLITE_DEFAULT_MMAP_SIZE // will be set by btree.c */
 
   *ppPager = pPager;
   return SQLITE_OK;
@@ -44027,6 +43314,11 @@ SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
       goto failed;
     }
     if( bHotJournal ){
+      if( pPager->readOnly ){
+        rc = SQLITE_READONLY_ROLLBACK;
+        goto failed;
+      }
+
       /* Get an EXCLUSIVE lock on the database file. At this point it is
       ** important that a RESERVED lock is not obtained on the way to the
       ** EXCLUSIVE lock. If it were, another process might open the
@@ -44124,9 +43416,11 @@ SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
       );
     }
 
-    if( !pPager->tempFile 
-     && (pPager->pBackup || sqlite3PcachePagecount(pPager->pPCache)>0) 
-    ){
+    if( !pPager->tempFile && (
+        pPager->pBackup 
+     || sqlite3PcachePagecount(pPager->pPCache)>0 
+     || USEFETCH(pPager)
+    )){
       /* The shared-lock has just been acquired on the database file
       ** and there are already pages in the cache (from a previous
       ** read or write transaction).  Check to see if the database
@@ -44152,7 +43446,7 @@ SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
       if( nPage>0 ){
         IOTRACE(("CKVERS %p %d\n", pPager, sizeof(dbFileVers)));
         rc = sqlite3OsRead(pPager->fd, &dbFileVers, sizeof(dbFileVers), 24);
-        if( rc!=SQLITE_OK ){
+        if( rc!=SQLITE_OK && rc!=SQLITE_IOERR_SHORT_READ ){
           goto failed;
         }
       }else{
@@ -44161,6 +43455,16 @@ SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
 
       if( memcmp(pPager->dbFileVers, dbFileVers, sizeof(dbFileVers))!=0 ){
         pager_reset(pPager);
+
+        /* Unmap the database file. It is possible that external processes
+        ** may have truncated the database file and then extended it back
+        ** to its original size while this process was not holding a lock.
+        ** In this case there may exist a Pager.pMap mapping that appears
+        ** to be the right size but is not actually valid. Avoid this
+        ** possibility by unmapping the db here. */
+        if( USEFETCH(pPager) ){
+          sqlite3OsUnfetch(pPager->fd, 0, 0);
+        }
       }
     }
 
@@ -44202,7 +43506,7 @@ SQLITE_PRIVATE int sqlite3PagerSharedLock(Pager *pPager){
 ** nothing to rollback, so this routine is a no-op.
 */ 
 static void pagerUnlockIfUnused(Pager *pPager){
-  if( (sqlite3PcacheRefCount(pPager->pPCache)==0) ){
+  if( pPager->nMmapOut==0 && (sqlite3PcacheRefCount(pPager->pPCache)==0) ){
     pagerUnlockAndRollback(pPager);
   }
 }
@@ -44230,7 +43534,7 @@ static void pagerUnlockIfUnused(Pager *pPager){
 ** page is initialized to all zeros. 
 **
 ** If noContent is true, it means that we do not care about the contents
-** of the page. This occurs in two seperate scenarios:
+** of the page. This occurs in two scenarios:
 **
 **   a) When reading a free-list leaf page from the database, and
 **
@@ -44261,13 +43565,27 @@ SQLITE_PRIVATE int sqlite3PagerAcquire(
   Pager *pPager,      /* The pager open on the database file */
   Pgno pgno,          /* Page number to fetch */
   DbPage **ppPage,    /* Write a pointer to the page here */
-  int noContent       /* Do not bother reading content from disk if true */
+  int flags           /* PAGER_GET_XXX flags */
 ){
-  int rc;
-  PgHdr *pPg;
+  int rc = SQLITE_OK;
+  PgHdr *pPg = 0;
+  u32 iFrame = 0;                 /* Frame to read from WAL file */
+  const int noContent = (flags & PAGER_GET_NOCONTENT);
+
+  /* It is acceptable to use a read-only (mmap) page for any page except
+  ** page 1 if there is no write-transaction open or the ACQUIRE_READONLY
+  ** flag was specified by the caller. And so long as the db is not a 
+  ** temporary or in-memory database.  */
+  const int bMmapOk = (pgno!=1 && USEFETCH(pPager)
+   && (pPager->eState==PAGER_READER || (flags & PAGER_GET_READONLY))
+#ifdef SQLITE_HAS_CODEC
+   && pPager->xCodec==0
+#endif
+  );
 
   assert( pPager->eState>=PAGER_READER );
   assert( assert_pager_state(pPager) );
+  assert( noContent==0 || bMmapOk==0 );
 
   if( pgno==0 ){
     return SQLITE_CORRUPT_BKPT;
@@ -44278,6 +43596,39 @@ SQLITE_PRIVATE int sqlite3PagerAcquire(
   if( pPager->errCode!=SQLITE_OK ){
     rc = pPager->errCode;
   }else{
+
+    if( bMmapOk && pagerUseWal(pPager) ){
+      rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
+      if( rc!=SQLITE_OK ) goto pager_acquire_err;
+    }
+
+    if( iFrame==0 && bMmapOk ){
+      void *pData = 0;
+
+      rc = sqlite3OsFetch(pPager->fd, 
+          (i64)(pgno-1) * pPager->pageSize, pPager->pageSize, &pData
+      );
+
+      if( rc==SQLITE_OK && pData ){
+        if( pPager->eState>PAGER_READER ){
+          (void)sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg);
+        }
+        if( pPg==0 ){
+          rc = pagerAcquireMapPage(pPager, pgno, pData, &pPg);
+        }else{
+          sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1)*pPager->pageSize, pData);
+        }
+        if( pPg ){
+          assert( rc==SQLITE_OK );
+          *ppPage = pPg;
+          return SQLITE_OK;
+        }
+      }
+      if( rc!=SQLITE_OK ){
+        goto pager_acquire_err;
+      }
+    }
+
     rc = sqlite3PcacheFetch(pPager->pPCache, pgno, 1, ppPage);
   }
 
@@ -44336,9 +43687,13 @@ SQLITE_PRIVATE int sqlite3PagerAcquire(
       memset(pPg->pData, 0, pPager->pageSize);
       IOTRACE(("ZERO %p %d\n", pPager, pgno));
     }else{
+      if( pagerUseWal(pPager) && bMmapOk==0 ){
+        rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
+        if( rc!=SQLITE_OK ) goto pager_acquire_err;
+      }
       assert( pPg->pPager==pPager );
       pPager->aStat[PAGER_STAT_MISS]++;
-      rc = readDbPage(pPg);
+      rc = readDbPage(pPg, iFrame);
       if( rc!=SQLITE_OK ){
         goto pager_acquire_err;
       }
@@ -44391,7 +43746,11 @@ SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno){
 SQLITE_PRIVATE void sqlite3PagerUnref(DbPage *pPg){
   if( pPg ){
     Pager *pPager = pPg->pPager;
-    sqlite3PcacheRelease(pPg);
+    if( pPg->flags & PGHDR_MMAP ){
+      pagerReleaseMapPage(pPg);
+    }else{
+      sqlite3PcacheRelease(pPg);
+    }
     pagerUnlockIfUnused(pPager);
   }
 }
@@ -44726,6 +44085,7 @@ SQLITE_PRIVATE int sqlite3PagerWrite(DbPage *pDbPage){
   Pager *pPager = pPg->pPager;
   Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);
 
+  assert( (pPg->flags & PGHDR_MMAP)==0 );
   assert( pPager->eState>=PAGER_WRITER_LOCKED );
   assert( pPager->eState!=PAGER_ERROR );
   assert( assert_pager_state(pPager) );
@@ -44737,13 +44097,13 @@ SQLITE_PRIVATE int sqlite3PagerWrite(DbPage *pDbPage){
     int ii;                   /* Loop counter */
     int needSync = 0;         /* True if any page has PGHDR_NEED_SYNC */
 
-    /* Set the doNotSyncSpill flag to 1. This is because we cannot allow
+    /* Set the doNotSpill NOSYNC bit to 1. This is because we cannot allow
     ** a journal header to be written between the pages journaled by
     ** this function.
     */
     assert( !MEMDB );
-    assert( pPager->doNotSyncSpill==0 );
-    pPager->doNotSyncSpill++;
+    assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)==0 );
+    pPager->doNotSpill |= SPILLFLAG_NOSYNC;
 
     /* This trick assumes that both the page-size and sector-size are
     ** an integer power of 2. It sets variable pg1 to the identifier
@@ -44802,8 +44162,8 @@ SQLITE_PRIVATE int sqlite3PagerWrite(DbPage *pDbPage){
       }
     }
 
-    assert( pPager->doNotSyncSpill==1 );
-    pPager->doNotSyncSpill--;
+    assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)!=0 );
+    pPager->doNotSpill &= ~SPILLFLAG_NOSYNC;
   }else{
     rc = pager_write(pDbPage);
   }
@@ -44893,7 +44253,7 @@ static int pager_incr_changecounter(Pager *pPager, int isDirectMode){
 # define DIRECT_MODE isDirectMode
 #endif
 
-  if( !pPager->changeCountDone && pPager->dbSize>0 ){
+  if( !pPager->changeCountDone && ALWAYS(pPager->dbSize>0) ){
     PgHdr *pPgHdr;                /* Reference to page 1 */
 
     assert( !pPager->tempFile && isOpen(pPager->fd) );
@@ -44925,6 +44285,11 @@ static int pager_incr_changecounter(Pager *pPager, int isDirectMode){
           pPager->aStat[PAGER_STAT_WRITE]++;
         }
         if( rc==SQLITE_OK ){
+          /* Update the pager's copy of the change-counter. Otherwise, the
+          ** next time a read transaction is opened the cache will be
+          ** flushed (as the change-counter values will not match).  */
+          const void *pCopy = (const void *)&((const char *)zBuf)[24];
+          memcpy(&pPager->dbFileVers, pCopy, sizeof(pPager->dbFileVers));
           pPager->changeCountDone = 1;
         }
       }else{
@@ -45111,38 +44476,6 @@ SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(
   #endif
       if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
   
-      /* If this transaction has made the database smaller, then all pages
-      ** being discarded by the truncation must be written to the journal
-      ** file. This can only happen in auto-vacuum mode.
-      **
-      ** Before reading the pages with page numbers larger than the 
-      ** current value of Pager.dbSize, set dbSize back to the value
-      ** that it took at the start of the transaction. Otherwise, the
-      ** calls to sqlite3PagerGet() return zeroed pages instead of 
-      ** reading data from the database file.
-      */
-  #ifndef SQLITE_OMIT_AUTOVACUUM
-      if( pPager->dbSize<pPager->dbOrigSize 
-       && pPager->journalMode!=PAGER_JOURNALMODE_OFF
-      ){
-        Pgno i;                                   /* Iterator variable */
-        const Pgno iSkip = PAGER_MJ_PGNO(pPager); /* Pending lock page */
-        const Pgno dbSize = pPager->dbSize;       /* Database image size */ 
-        pPager->dbSize = pPager->dbOrigSize;
-        for( i=dbSize+1; i<=pPager->dbOrigSize; i++ ){
-          if( !sqlite3BitvecTest(pPager->pInJournal, i) && i!=iSkip ){
-            PgHdr *pPage;             /* Page to journal */
-            rc = sqlite3PagerGet(pPager, i, &pPage);
-            if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
-            rc = sqlite3PagerWrite(pPage);
-            sqlite3PagerUnref(pPage);
-            if( rc!=SQLITE_OK ) goto commit_phase_one_exit;
-          }
-        }
-        pPager->dbSize = dbSize;
-      } 
-  #endif
-  
       /* Write the master journal name into the journal file. If a master 
       ** journal file name has already been written to the journal file, 
       ** or if zMaster is NULL (no master journal), then this call is a no-op.
@@ -45170,11 +44503,14 @@ SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(
         goto commit_phase_one_exit;
       }
       sqlite3PcacheCleanAll(pPager->pPCache);
-  
-      /* If the file on disk is not the same size as the database image,
-      ** then use pager_truncate to grow or shrink the file here.
-      */
-      if( pPager->dbSize!=pPager->dbFileSize ){
+
+      /* If the file on disk is smaller than the database image, use 
+      ** pager_truncate to grow the file here. This can happen if the database
+      ** image was extended as part of the current transaction and then the
+      ** last page in the db image moved to the free-list. In this case the
+      ** last page is never written out to disk, leaving the database file
+      ** undersized. Fix this now if it is the case.  */
+      if( pPager->dbSize>pPager->dbFileSize ){
         Pgno nNew = pPager->dbSize - (pPager->dbSize==PAGER_MJ_PGNO(pPager));
         assert( pPager->eState==PAGER_WRITER_DBMOD );
         rc = pager_truncate(pPager, nNew);
@@ -45247,7 +44583,7 @@ SQLITE_PRIVATE int sqlite3PagerCommitPhaseTwo(Pager *pPager){
   }
 
   PAGERTRACE(("COMMIT %d\n", PAGERID(pPager)));
-  rc = pager_end_transaction(pPager, pPager->setMaster);
+  rc = pager_end_transaction(pPager, pPager->setMaster, 1);
   return pager_error(pPager, rc);
 }
 
@@ -45292,11 +44628,11 @@ SQLITE_PRIVATE int sqlite3PagerRollback(Pager *pPager){
   if( pagerUseWal(pPager) ){
     int rc2;
     rc = sqlite3PagerSavepoint(pPager, SAVEPOINT_ROLLBACK, -1);
-    rc2 = pager_end_transaction(pPager, pPager->setMaster);
+    rc2 = pager_end_transaction(pPager, pPager->setMaster, 0);
     if( rc==SQLITE_OK ) rc = rc2;
   }else if( !isOpen(pPager->jfd) || pPager->eState==PAGER_WRITER_LOCKED ){
     int eState = pPager->eState;
-    rc = pager_end_transaction(pPager, 0);
+    rc = pager_end_transaction(pPager, 0, 0);
     if( !MEMDB && eState>PAGER_WRITER_LOCKED ){
       /* This can happen using journal_mode=off. Move the pager to the error 
       ** state to indicate that the contents of the cache may not be trusted.
@@ -45311,7 +44647,7 @@ SQLITE_PRIVATE int sqlite3PagerRollback(Pager *pPager){
   }
 
   assert( pPager->eState==PAGER_READER || rc!=SQLITE_OK );
-  assert( rc==SQLITE_OK || rc==SQLITE_FULL
+  assert( rc==SQLITE_OK || rc==SQLITE_FULL || rc==SQLITE_CORRUPT
           || rc==SQLITE_NOMEM || (rc&0xFF)==SQLITE_IOERR );
 
   /* If an error occurs during a ROLLBACK, we can no longer trust the pager
@@ -45608,7 +44944,27 @@ SQLITE_PRIVATE void sqlite3PagerSetCodec(
 SQLITE_PRIVATE void *sqlite3PagerGetCodec(Pager *pPager){
   return pPager->pCodec;
 }
-#endif
+
+/*
+** This function is called by the wal module when writing page content
+** into the log file.
+**
+** This function returns a pointer to a buffer containing the encrypted
+** page content. If a malloc fails, this function may return NULL.
+*/
+SQLITE_PRIVATE void *sqlite3PagerCodec(PgHdr *pPg){
+  void *aData = 0;
+  CODEC2(pPg->pPager, pPg->pData, pPg->pgno, 6, return 0, aData);
+  return aData;
+}
+
+/*
+** Return the current pager state
+*/
+SQLITE_PRIVATE int sqlite3PagerState(Pager *pPager){
+  return pPager->eState;
+}
+#endif /* SQLITE_HAS_CODEC */
 
 #ifndef SQLITE_OMIT_AUTOVACUUM
 /*
@@ -45694,7 +45050,8 @@ SQLITE_PRIVATE int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, i
   */
   if( (pPg->flags&PGHDR_NEED_SYNC) && !isCommit ){
     needSyncPgno = pPg->pgno;
-    assert( pageInJournal(pPg) || pPg->pgno>pPager->dbOrigSize );
+    assert( pPager->journalMode==PAGER_JOURNALMODE_OFF ||
+            pageInJournal(pPg) || pPg->pgno>pPager->dbOrigSize );
     assert( pPg->flags&PGHDR_DIRTY );
   }
 
@@ -46044,11 +45401,12 @@ static int pagerOpenWal(Pager *pPager){
   ** (e.g. due to malloc() failure), return an error code.
   */
   if( rc==SQLITE_OK ){
-    rc = sqlite3WalOpen(pPager->pVfs, 
+    rc = sqlite3WalOpen(pPager->pVfs,
         pPager->fd, pPager->zWal, pPager->exclusiveMode,
         pPager->journalSizeLimit, &pPager->pWal
     );
   }
+  pagerFixMaplimit(pPager);
 
   return rc;
 }
@@ -46139,11 +45497,14 @@ SQLITE_PRIVATE int sqlite3PagerCloseWal(Pager *pPager){
       rc = sqlite3WalClose(pPager->pWal, pPager->ckptSyncFlags,
                            pPager->pageSize, (u8*)pPager->pTmpSpace);
       pPager->pWal = 0;
+      pagerFixMaplimit(pPager);
     }
   }
   return rc;
 }
 
+#endif /* !SQLITE_OMIT_WAL */
+
 #ifdef SQLITE_ENABLE_ZIPVFS
 /*
 ** A read-lock must be held on the pager when this function is called. If
@@ -46158,23 +45519,6 @@ SQLITE_PRIVATE int sqlite3PagerWalFramesize(Pager *pPager){
 }
 #endif
 
-#ifdef SQLITE_HAS_CODEC
-/*
-** This function is called by the wal module when writing page content
-** into the log file.
-**
-** This function returns a pointer to a buffer containing the encrypted
-** page content. If a malloc fails, this function may return NULL.
-*/
-SQLITE_PRIVATE void *sqlite3PagerCodec(PgHdr *pPg){
-  void *aData = 0;
-  CODEC2(pPg->pPager, pPg->pData, pPg->pgno, 6, return 0, aData);
-  return aData;
-}
-#endif /* SQLITE_HAS_CODEC */
-
-#endif /* !SQLITE_OMIT_WAL */
-
 #endif /* SQLITE_OMIT_DISKIO */
 
 /************** End of pager.c ***********************************************/
@@ -46323,14 +45667,15 @@ SQLITE_PRIVATE void *sqlite3PagerCodec(PgHdr *pPg){
 ** byte order of the host computer.
 **
 ** The purpose of the wal-index is to answer this question quickly:  Given
-** a page number P, return the index of the last frame for page P in the WAL,
-** or return NULL if there are no frames for page P in the WAL.
+** a page number P and a maximum frame index M, return the index of the 
+** last frame in the wal before frame M for page P in the WAL, or return
+** NULL if there are no frames for page P in the WAL prior to M.
 **
 ** The wal-index consists of a header region, followed by an one or
 ** more index blocks.  
 **
 ** The wal-index header contains the total number of frames within the WAL
-** in the the mxFrame field.  
+** in the mxFrame field.
 **
 ** Each index block except for the first contains information on 
 ** HASHTABLE_NPAGE frames. The first index block contains information on
@@ -47378,6 +46723,7 @@ finished:
     pInfo->nBackfill = 0;
     pInfo->aReadMark[0] = 0;
     for(i=1; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED;
+    if( pWal->hdr.mxFrame ) pInfo->aReadMark[1] = pWal->hdr.mxFrame;
 
     /* If more than one frame was recovered from the log file, report an
     ** event via sqlite3_log(). This is to help with identifying performance
@@ -47385,8 +46731,9 @@ finished:
     ** checkpointing the log file.
     */
     if( pWal->hdr.nPage ){
-      sqlite3_log(SQLITE_OK, "Recovered %d frames from WAL file %s",
-          pWal->hdr.nPage, pWal->zWalName
+      sqlite3_log(SQLITE_NOTICE_RECOVER_WAL,
+          "recovered %d frames from WAL file %s",
+          pWal->hdr.mxFrame, pWal->zWalName
       );
     }
   }
@@ -47878,7 +47225,7 @@ static int walCheckpoint(
       assert( y<=pWal->hdr.mxFrame );
       rc = walBusyLock(pWal, xBusy, pBusyArg, WAL_READ_LOCK(i), 1);
       if( rc==SQLITE_OK ){
-        pInfo->aReadMark[i] = READMARK_NOT_USED;
+        pInfo->aReadMark[i] = (i==1 ? mxSafeFrame : READMARK_NOT_USED);
         walUnlockExclusive(pWal, WAL_READ_LOCK(i), 1);
       }else if( rc==SQLITE_BUSY ){
         mxSafeFrame = y;
@@ -47900,8 +47247,8 @@ static int walCheckpoint(
       rc = sqlite3OsSync(pWal->pWalFd, sync_flags);
     }
 
-    /* If the database file may grow as a result of this checkpoint, hint
-    ** about the eventual size of the db file to the VFS layer. 
+    /* If the database may grow as a result of this checkpoint, hint
+    ** about the eventual size of the db file to the VFS layer.
     */
     if( rc==SQLITE_OK ){
       i64 nReq = ((i64)mxPage * szPage);
@@ -47911,6 +47258,7 @@ static int walCheckpoint(
       }
     }
 
+
     /* Iterate through the contents of the WAL, copying data to the db file. */
     while( rc==SQLITE_OK && 0==walIteratorNext(pIter, &iDbpage, &iFrame) ){
       i64 iOffset;
@@ -48465,19 +47813,17 @@ SQLITE_PRIVATE void sqlite3WalEndReadTransaction(Wal *pWal){
 }
 
 /*
-** Read a page from the WAL, if it is present in the WAL and if the 
-** current read transaction is configured to use the WAL.  
+** Search the wal file for page pgno. If found, set *piRead to the frame that
+** contains the page. Otherwise, if pgno is not in the wal file, set *piRead
+** to zero.
 **
-** The *pInWal is set to 1 if the requested page is in the WAL and
-** has been loaded.  Or *pInWal is set to 0 if the page was not in 
-** the WAL and needs to be read out of the database.
+** Return SQLITE_OK if successful, or an error code if an error occurs. If an
+** error does occur, the final value of *piRead is undefined.
 */
-SQLITE_PRIVATE int sqlite3WalRead(
+SQLITE_PRIVATE int sqlite3WalFindFrame(
   Wal *pWal,                      /* WAL handle */
   Pgno pgno,                      /* Database page number to read data for */
-  int *pInWal,                    /* OUT: True if data is read from WAL */
-  int nOut,                       /* Size of buffer pOut in bytes */
-  u8 *pOut                        /* Buffer to write page data to */
+  u32 *piRead                     /* OUT: Frame number (or zero) */
 ){
   u32 iRead = 0;                  /* If !=0, WAL frame to return data from */
   u32 iLast = pWal->hdr.mxFrame;  /* Last page in WAL for this reader */
@@ -48493,7 +47839,7 @@ SQLITE_PRIVATE int sqlite3WalRead(
   ** WAL were empty.
   */
   if( iLast==0 || pWal->readLock==0 ){
-    *pInWal = 0;
+    *piRead = 0;
     return SQLITE_OK;
   }
 
@@ -48564,26 +47910,31 @@ SQLITE_PRIVATE int sqlite3WalRead(
   }
 #endif
 
-  /* If iRead is non-zero, then it is the log frame number that contains the
-  ** required page. Read and return data from the log file.
-  */
-  if( iRead ){
-    int sz;
-    i64 iOffset;
-    sz = pWal->hdr.szPage;
-    sz = (sz&0xfe00) + ((sz&0x0001)<<16);
-    testcase( sz<=32768 );
-    testcase( sz>=65536 );
-    iOffset = walFrameOffset(iRead, sz) + WAL_FRAME_HDRSIZE;
-    *pInWal = 1;
-    /* testcase( IS_BIG_INT(iOffset) ); // requires a 4GiB WAL */
-    return sqlite3OsRead(pWal->pWalFd, pOut, (nOut>sz ? sz : nOut), iOffset);
-  }
-
-  *pInWal = 0;
+  *piRead = iRead;
   return SQLITE_OK;
 }
 
+/*
+** Read the contents of frame iRead from the wal file into buffer pOut
+** (which is nOut bytes in size). Return SQLITE_OK if successful, or an
+** error code otherwise.
+*/
+SQLITE_PRIVATE int sqlite3WalReadFrame(
+  Wal *pWal,                      /* WAL handle */
+  u32 iRead,                      /* Frame to read */
+  int nOut,                       /* Size of buffer pOut in bytes */
+  u8 *pOut                        /* Buffer to write page data to */
+){
+  int sz;
+  i64 iOffset;
+  sz = pWal->hdr.szPage;
+  sz = (sz&0xfe00) + ((sz&0x0001)<<16);
+  testcase( sz<=32768 );
+  testcase( sz>=65536 );
+  iOffset = walFrameOffset(iRead, sz) + WAL_FRAME_HDRSIZE;
+  /* testcase( IS_BIG_INT(iOffset) ); // requires a 4GiB WAL */
+  return sqlite3OsRead(pWal->pWalFd, pOut, (nOut>sz ? sz : nOut), iOffset);
+}
 
 /* 
 ** Return the size of the database in pages (or zero, if unknown).
@@ -48636,7 +47987,7 @@ SQLITE_PRIVATE int sqlite3WalBeginWriteTransaction(Wal *pWal){
   if( memcmp(&pWal->hdr, (void *)walIndexHdr(pWal), sizeof(WalIndexHdr))!=0 ){
     walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
     pWal->writeLock = 0;
-    rc = SQLITE_BUSY;
+    rc = SQLITE_BUSY_SNAPSHOT;
   }
 
   return rc;
@@ -48696,7 +48047,7 @@ SQLITE_PRIVATE int sqlite3WalUndo(Wal *pWal, int (*xUndo)(void *, Pgno), void *p
       assert( walFramePgno(pWal, iFrame)!=1 );
       rc = xUndo(pUndoCtx, walFramePgno(pWal, iFrame));
     }
-    walCleanupHash(pWal);
+    if( iMax!=pWal->hdr.mxFrame ) walCleanupHash(pWal);
   }
   assert( rc==SQLITE_OK );
   return rc;
@@ -48791,7 +48142,8 @@ static int walRestartLog(Wal *pWal){
         aSalt[1] = salt1;
         walIndexWriteHdr(pWal);
         pInfo->nBackfill = 0;
-        for(i=1; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED;
+        pInfo->aReadMark[1] = 0;
+        for(i=2; i<WAL_NREADER; i++) pInfo->aReadMark[i] = READMARK_NOT_USED;
         assert( pInfo->aReadMark[0]==0 );
         walUnlockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1);
       }else if( rc!=SQLITE_BUSY ){
@@ -49005,7 +48357,7 @@ SQLITE_PRIVATE int sqlite3WalFrames(
   */
   if( isCommit && (sync_flags & WAL_SYNC_TRANSACTIONS)!=0 ){
     if( pWal->padToSectorBoundary ){
-      int sectorSize = sqlite3OsSectorSize(pWal->pWalFd);
+      int sectorSize = sqlite3SectorSize(pWal->pWalFd);
       w.iSyncPoint = ((iOffset+sectorSize-1)/sectorSize)*sectorSize;
       while( iOffset<w.iSyncPoint ){
         rc = walWriteOneFrame(&w, pLast, nTruncate, iOffset);
@@ -49129,6 +48481,9 @@ SQLITE_PRIVATE int sqlite3WalCheckpoint(
   /* Read the wal-index header. */
   if( rc==SQLITE_OK ){
     rc = walIndexReadHdr(pWal, &isChanged);
+    if( isChanged && pWal->pDbFd->pMethods->iVersion>=3 ){
+      sqlite3OsUnfetch(pWal->pDbFd, 0, 0);
+    }
   }
 
   /* Copy data from the log to the database file. */
@@ -49695,6 +49050,7 @@ struct BtShared {
 #ifndef SQLITE_OMIT_AUTOVACUUM
   u8 autoVacuum;        /* True if auto-vacuum is enabled */
   u8 incrVacuum;        /* True if incr-vacuum is enabled */
+  u8 bDoTruncate;       /* True to truncate db on commit */
 #endif
   u8 inTransaction;     /* Transaction state */
   u8 max1bytePayload;   /* Maximum first byte of cell for a 1-byte payload */
@@ -49794,6 +49150,7 @@ struct BtCursor {
 #ifndef SQLITE_OMIT_INCRBLOB
   u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
 #endif
+  u8 hints;                             /* As configured by CursorSetHints() */
   i16 iPage;                            /* Index of current page in apPage */
   u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
   MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
@@ -49802,14 +49159,19 @@ struct BtCursor {
 /*
 ** Potential values for BtCursor.eState.
 **
-** CURSOR_VALID:
-**   Cursor points to a valid entry. getPayload() etc. may be called.
-**
 ** CURSOR_INVALID:
 **   Cursor does not point to a valid entry. This can happen (for example) 
 **   because the table is empty or because BtreeCursorFirst() has not been
 **   called.
 **
+** CURSOR_VALID:
+**   Cursor points to a valid entry. getPayload() etc. may be called.
+**
+** CURSOR_SKIPNEXT:
+**   Cursor is valid except that the Cursor.skipNext field is non-zero
+**   indicating that the next sqlite3BtreeNext() or sqlite3BtreePrevious()
+**   operation should be a no-op.
+**
 ** CURSOR_REQUIRESEEK:
 **   The table that this cursor was opened on still exists, but has been 
 **   modified since the cursor was last used. The cursor position is saved
@@ -49826,8 +49188,9 @@ struct BtCursor {
 */
 #define CURSOR_INVALID           0
 #define CURSOR_VALID             1
-#define CURSOR_REQUIRESEEK       2
-#define CURSOR_FAULT             3
+#define CURSOR_SKIPNEXT          2
+#define CURSOR_REQUIRESEEK       3
+#define CURSOR_FAULT             4
 
 /* 
 ** The database page the PENDING_BYTE occupies. This page is never used.
@@ -50260,6 +49623,25 @@ int sqlite3BtreeTrace=1;  /* True to enable tracing */
 */
 #define get2byteNotZero(X)  (((((int)get2byte(X))-1)&0xffff)+1)
 
+/*
+** Values passed as the 5th argument to allocateBtreePage()
+*/
+#define BTALLOC_ANY   0           /* Allocate any page */
+#define BTALLOC_EXACT 1           /* Allocate exact page if possible */
+#define BTALLOC_LE    2           /* Allocate any page <= the parameter */
+
+/*
+** Macro IfNotOmitAV(x) returns (x) if SQLITE_OMIT_AUTOVACUUM is not 
+** defined, or 0 if it is. For example:
+**
+**   bIncrVacuum = IfNotOmitAV(pBtShared->incrVacuum);
+*/
+#ifndef SQLITE_OMIT_AUTOVACUUM
+#define IfNotOmitAV(expr) (expr)
+#else
+#define IfNotOmitAV(expr) 0
+#endif
+
 #ifndef SQLITE_OMIT_SHARED_CACHE
 /*
 ** A list of BtShared objects that are eligible for participation
@@ -50773,6 +50155,19 @@ static void btreeClearHasContent(BtShared *pBt){
   pBt->pHasContent = 0;
 }
 
+/*
+** Release all of the apPage[] pages for a cursor.
+*/
+static void btreeReleaseAllCursorPages(BtCursor *pCur){
+  int i;
+  for(i=0; i<=pCur->iPage; i++){
+    releasePage(pCur->apPage[i]);
+    pCur->apPage[i] = 0;
+  }
+  pCur->iPage = -1;
+}
+
+
 /*
 ** Save the current cursor position in the variables BtCursor.nKey 
 ** and BtCursor.pKey. The cursor's state is set to CURSOR_REQUIRESEEK.
@@ -50812,12 +50207,7 @@ static int saveCursorPosition(BtCursor *pCur){
   assert( !pCur->apPage[0]->intKey || !pCur->pKey );
 
   if( rc==SQLITE_OK ){
-    int i;
-    for(i=0; i<=pCur->iPage; i++){
-      releasePage(pCur->apPage[i]);
-      pCur->apPage[i] = 0;
-    }
-    pCur->iPage = -1;
+    btreeReleaseAllCursorPages(pCur);
     pCur->eState = CURSOR_REQUIRESEEK;
   }
 
@@ -50835,11 +50225,15 @@ static int saveAllCursors(BtShared *pBt, Pgno iRoot, BtCursor *pExcept){
   assert( sqlite3_mutex_held(pBt->mutex) );
   assert( pExcept==0 || pExcept->pBt==pBt );
   for(p=pBt->pCursor; p; p=p->pNext){
-    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) && 
-        p->eState==CURSOR_VALID ){
-      int rc = saveCursorPosition(p);
-      if( SQLITE_OK!=rc ){
-        return rc;
+    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) ){
+      if( p->eState==CURSOR_VALID ){
+        int rc = saveCursorPosition(p);
+        if( SQLITE_OK!=rc ){
+          return rc;
+        }
+      }else{
+        testcase( p->iPage>0 );
+        btreeReleaseAllCursorPages(p);
       }
     }
   }
@@ -50910,6 +50304,9 @@ static int btreeRestoreCursorPosition(BtCursor *pCur){
     sqlite3_free(pCur->pKey);
     pCur->pKey = 0;
     assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
+    if( pCur->skipNext && pCur->eState==CURSOR_VALID ){
+      pCur->eState = CURSOR_SKIPNEXT;
+    }
   }
   return rc;
 }
@@ -50935,7 +50332,7 @@ SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor *pCur, int *pHasMoved){
     *pHasMoved = 1;
     return rc;
   }
-  if( pCur->eState!=CURSOR_VALID || pCur->skipNext!=0 ){
+  if( pCur->eState!=CURSOR_VALID || NEVER(pCur->skipNext!=0) ){
     *pHasMoved = 1;
   }else{
     *pHasMoved = 0;
@@ -51123,7 +50520,8 @@ static void btreeParseCellPtr(
   assert( n==4-4*pPage->leaf );
   if( pPage->intKey ){
     if( pPage->hasData ){
-      n += getVarint32(&pCell[n], nPayload);
+      assert( n==0 );
+      n = getVarint32(pCell, nPayload);
     }else{
       nPayload = 0;
     }
@@ -51401,7 +50799,7 @@ static int allocateSpace(MemPage *pPage, int nByte, int *pIdx){
   }else if( gap+2<=top ){
     /* Search the freelist looking for a free slot big enough to satisfy 
     ** the request. The allocation is made from the first free slot in 
-    ** the list that is large enough to accomadate it.
+    ** the list that is large enough to accommodate it.
     */
     int pc, addr;
     for(addr=hdr+1; (pc = get2byte(&data[addr]))>0; addr=pc){
@@ -51678,7 +51076,7 @@ static int btreeInitPage(MemPage *pPage){
       size = get2byte(&data[pc+2]);
       if( (next>0 && next<=pc+size+3) || pc+size>usableSize ){
         /* Free blocks must be in ascending order. And the last byte of
-	** the free-block must lie on the database page.  */
+        ** the free-block must lie on the database page.  */
         return SQLITE_CORRUPT_BKPT; 
       }
       nFree = nFree + size;
@@ -51767,13 +51165,14 @@ static int btreeGetPage(
   BtShared *pBt,       /* The btree */
   Pgno pgno,           /* Number of the page to fetch */
   MemPage **ppPage,    /* Return the page in this parameter */
-  int noContent        /* Do not load page content if true */
+  int flags            /* PAGER_GET_NOCONTENT or PAGER_GET_READONLY */
 ){
   int rc;
   DbPage *pDbPage;
 
+  assert( flags==0 || flags==PAGER_GET_NOCONTENT || flags==PAGER_GET_READONLY );
   assert( sqlite3_mutex_held(pBt->mutex) );
-  rc = sqlite3PagerAcquire(pBt->pPager, pgno, (DbPage**)&pDbPage, noContent);
+  rc = sqlite3PagerAcquire(pBt->pPager, pgno, (DbPage**)&pDbPage, flags);
   if( rc ) return rc;
   *ppPage = btreePageFromDbPage(pDbPage, pgno, pBt);
   return SQLITE_OK;
@@ -51816,17 +51215,19 @@ SQLITE_PRIVATE u32 sqlite3BtreeLastPage(Btree *p){
 ** may remain unchanged, or it may be set to an invalid value.
 */
 static int getAndInitPage(
-  BtShared *pBt,          /* The database file */
-  Pgno pgno,           /* Number of the page to get */
-  MemPage **ppPage     /* Write the page pointer here */
+  BtShared *pBt,                  /* The database file */
+  Pgno pgno,                      /* Number of the page to get */
+  MemPage **ppPage,               /* Write the page pointer here */
+  int bReadonly                   /* PAGER_GET_READONLY or 0 */
 ){
   int rc;
   assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( bReadonly==PAGER_GET_READONLY || bReadonly==0 );
 
   if( pgno>btreePagecount(pBt) ){
     rc = SQLITE_CORRUPT_BKPT;
   }else{
-    rc = btreeGetPage(pBt, pgno, ppPage, 0);
+    rc = btreeGetPage(pBt, pgno, ppPage, bReadonly);
     if( rc==SQLITE_OK ){
       rc = btreeInitPage(*ppPage);
       if( rc!=SQLITE_OK ){
@@ -52057,6 +51458,7 @@ SQLITE_PRIVATE int sqlite3BtreeOpen(
     rc = sqlite3PagerOpen(pVfs, &pBt->pPager, zFilename,
                           EXTRA_SIZE, flags, vfsFlags, pageReinit);
     if( rc==SQLITE_OK ){
+      sqlite3PagerSetMmapLimit(pBt->pPager, db->szMmap);
       rc = sqlite3PagerReadFileheader(pBt->pPager,sizeof(zDbHeader),zDbHeader);
     }
     if( rc!=SQLITE_OK ){
@@ -52323,6 +51725,19 @@ SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree *p, int mxPage){
   return SQLITE_OK;
 }
 
+/*
+** Change the limit on the amount of the database file that may be
+** memory mapped.
+*/
+SQLITE_PRIVATE int sqlite3BtreeSetMmapLimit(Btree *p, sqlite3_int64 szMmap){
+  BtShared *pBt = p->pBt;
+  assert( sqlite3_mutex_held(p->db->mutex) );
+  sqlite3BtreeEnter(p);
+  sqlite3PagerSetMmapLimit(pBt->pPager, szMmap);
+  sqlite3BtreeLeave(p);
+  return SQLITE_OK;
+}
+
 /*
 ** Change the way data is synced to disk in order to increase or decrease
 ** how well the database resists damage due to OS crashes and power
@@ -52332,17 +51747,14 @@ SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree *p, int mxPage){
 ** probability of damage to near zero but with a write performance reduction.
 */
 #ifndef SQLITE_OMIT_PAGER_PRAGMAS
-SQLITE_PRIVATE int sqlite3BtreeSetSafetyLevel(
+SQLITE_PRIVATE int sqlite3BtreeSetPagerFlags(
   Btree *p,              /* The btree to set the safety level on */
-  int level,             /* PRAGMA synchronous.  1=OFF, 2=NORMAL, 3=FULL */
-  int fullSync,          /* PRAGMA fullfsync. */
-  int ckptFullSync       /* PRAGMA checkpoint_fullfync */
+  unsigned pgFlags       /* Various PAGER_* flags */
 ){
   BtShared *pBt = p->pBt;
   assert( sqlite3_mutex_held(p->db->mutex) );
-  assert( level>=1 && level<=3 );
   sqlite3BtreeEnter(p);
-  sqlite3PagerSetSafetyLevel(pBt->pPager, level, fullSync, ckptFullSync);
+  sqlite3PagerSetFlags(pBt->pPager, pgFlags);
   sqlite3BtreeLeave(p);
   return SQLITE_OK;
 }
@@ -52417,6 +51829,24 @@ SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree *p){
   return p->pBt->pageSize;
 }
 
+#if defined(SQLITE_HAS_CODEC) || defined(SQLITE_DEBUG)
+/*
+** This function is similar to sqlite3BtreeGetReserve(), except that it
+** may only be called if it is guaranteed that the b-tree mutex is already
+** held.
+**
+** This is useful in one special case in the backup API code where it is
+** known that the shared b-tree mutex is held, but the mutex on the 
+** database handle that owns *p is not. In this case if sqlite3BtreeEnter()
+** were to be called, it might collide with some other operation on the
+** database handle that owns *p, causing undefined behavior.
+*/
+SQLITE_PRIVATE int sqlite3BtreeGetReserveNoMutex(Btree *p){
+  assert( sqlite3_mutex_held(p->pBt->mutex) );
+  return p->pBt->pageSize - p->pBt->usableSize;
+}
+#endif /* SQLITE_HAS_CODEC || SQLITE_DEBUG */
+
 #if !defined(SQLITE_OMIT_PAGER_PRAGMAS) || !defined(SQLITE_OMIT_VACUUM)
 /*
 ** Return the number of bytes of space at the end of every page that
@@ -52666,6 +52096,29 @@ page1_init_failed:
   return rc;
 }
 
+#ifndef NDEBUG
+/*
+** Return the number of cursors open on pBt. This is for use
+** in assert() expressions, so it is only compiled if NDEBUG is not
+** defined.
+**
+** Only write cursors are counted if wrOnly is true.  If wrOnly is
+** false then all cursors are counted.
+**
+** For the purposes of this routine, a cursor is any cursor that
+** is capable of reading or writing to the databse.  Cursors that
+** have been tripped into the CURSOR_FAULT state are not counted.
+*/
+static int countValidCursors(BtShared *pBt, int wrOnly){
+  BtCursor *pCur;
+  int r = 0;
+  for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
+    if( (wrOnly==0 || pCur->wrFlag) && pCur->eState!=CURSOR_FAULT ) r++; 
+  }
+  return r;
+}
+#endif
+
 /*
 ** If there are no outstanding cursors and we are not in the middle
 ** of a transaction but there is a read lock on the database, then
@@ -52676,7 +52129,7 @@ page1_init_failed:
 */
 static void unlockBtreeIfUnused(BtShared *pBt){
   assert( sqlite3_mutex_held(pBt->mutex) );
-  assert( pBt->pCursor==0 || pBt->inTransaction>TRANS_NONE );
+  assert( countValidCursors(pBt,0)==0 || pBt->inTransaction>TRANS_NONE );
   if( pBt->inTransaction==TRANS_NONE && pBt->pPage1!=0 ){
     assert( pBt->pPage1->aData );
     assert( sqlite3PagerRefcount(pBt->pPager)==1 );
@@ -52730,6 +52183,20 @@ static int newDatabase(BtShared *pBt){
   return SQLITE_OK;
 }
 
+/*
+** Initialize the first page of the database file (creating a database
+** consisting of a single page and no schema objects). Return SQLITE_OK
+** if successful, or an SQLite error code otherwise.
+*/
+SQLITE_PRIVATE int sqlite3BtreeNewDb(Btree *p){
+  int rc;
+  sqlite3BtreeEnter(p);
+  p->pBt->nPage = 0;
+  rc = newDatabase(p->pBt);
+  sqlite3BtreeLeave(p);
+  return rc;
+}
+
 /*
 ** Attempt to start a new transaction. A write-transaction
 ** is started if the second argument is nonzero, otherwise a read-
@@ -52780,6 +52247,7 @@ SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree *p, int wrflag){
   if( p->inTrans==TRANS_WRITE || (p->inTrans==TRANS_READ && !wrflag) ){
     goto trans_begun;
   }
+  assert( IfNotOmitAV(pBt->bDoTruncate)==0 );
 
   /* Write transactions are not possible on a read-only database */
   if( (pBt->btsFlags & BTS_READ_ONLY)!=0 && wrflag ){
@@ -52852,7 +52320,7 @@ SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree *p, int wrflag){
       pBt->nTransaction++;
 #ifndef SQLITE_OMIT_SHARED_CACHE
       if( p->sharable ){
-	assert( p->lock.pBtree==p && p->lock.iTable==1 );
+        assert( p->lock.pBtree==p && p->lock.iTable==1 );
         p->lock.eLock = READ_LOCK;
         p->lock.pNext = pBt->pLock;
         pBt->pLock = &p->lock;
@@ -53096,24 +52564,23 @@ static int relocatePage(
 static int allocateBtreePage(BtShared *, MemPage **, Pgno *, Pgno, u8);
 
 /*
-** Perform a single step of an incremental-vacuum. If successful,
-** return SQLITE_OK. If there is no work to do (and therefore no
-** point in calling this function again), return SQLITE_DONE.
+** Perform a single step of an incremental-vacuum. If successful, return
+** SQLITE_OK. If there is no work to do (and therefore no point in 
+** calling this function again), return SQLITE_DONE. Or, if an error 
+** occurs, return some other error code.
 **
-** More specificly, this function attempts to re-organize the 
-** database so that the last page of the file currently in use
-** is no longer in use.
+** More specificly, this function attempts to re-organize the database so 
+** that the last page of the file currently in use is no longer in use.
 **
-** If the nFin parameter is non-zero, this function assumes
-** that the caller will keep calling incrVacuumStep() until
-** it returns SQLITE_DONE or an error, and that nFin is the
-** number of pages the database file will contain after this 
-** process is complete.  If nFin is zero, it is assumed that
-** incrVacuumStep() will be called a finite amount of times
-** which may or may not empty the freelist.  A full autovacuum
-** has nFin>0.  A "PRAGMA incremental_vacuum" has nFin==0.
+** Parameter nFin is the number of pages that this database would contain
+** were this function called until it returns SQLITE_DONE.
+**
+** If the bCommit parameter is non-zero, this function assumes that the 
+** caller will keep calling incrVacuumStep() until it returns SQLITE_DONE 
+** or an error. bCommit is passed true for an auto-vacuum-on-commmit 
+** operation, or false for an incremental vacuum.
 */
-static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg){
+static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg, int bCommit){
   Pgno nFreeList;           /* Number of pages still on the free-list */
   int rc;
 
@@ -53138,15 +52605,15 @@ static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg){
     }
 
     if( eType==PTRMAP_FREEPAGE ){
-      if( nFin==0 ){
+      if( bCommit==0 ){
         /* Remove the page from the files free-list. This is not required
-        ** if nFin is non-zero. In that case, the free-list will be
+        ** if bCommit is non-zero. In that case, the free-list will be
         ** truncated to zero after this function returns, so it doesn't 
         ** matter if it still contains some garbage entries.
         */
         Pgno iFreePg;
         MemPage *pFreePg;
-        rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, iLastPg, 1);
+        rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, iLastPg, BTALLOC_EXACT);
         if( rc!=SQLITE_OK ){
           return rc;
         }
@@ -53156,34 +52623,37 @@ static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg){
     } else {
       Pgno iFreePg;             /* Index of free page to move pLastPg to */
       MemPage *pLastPg;
+      u8 eMode = BTALLOC_ANY;   /* Mode parameter for allocateBtreePage() */
+      Pgno iNear = 0;           /* nearby parameter for allocateBtreePage() */
 
       rc = btreeGetPage(pBt, iLastPg, &pLastPg, 0);
       if( rc!=SQLITE_OK ){
         return rc;
       }
 
-      /* If nFin is zero, this loop runs exactly once and page pLastPg
+      /* If bCommit is zero, this loop runs exactly once and page pLastPg
       ** is swapped with the first free page pulled off the free list.
       **
-      ** On the other hand, if nFin is greater than zero, then keep
+      ** On the other hand, if bCommit is greater than zero, then keep
       ** looping until a free-page located within the first nFin pages
       ** of the file is found.
       */
+      if( bCommit==0 ){
+        eMode = BTALLOC_LE;
+        iNear = nFin;
+      }
       do {
         MemPage *pFreePg;
-        rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, 0, 0);
+        rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, iNear, eMode);
         if( rc!=SQLITE_OK ){
           releasePage(pLastPg);
           return rc;
         }
         releasePage(pFreePg);
-      }while( nFin!=0 && iFreePg>nFin );
+      }while( bCommit && iFreePg>nFin );
       assert( iFreePg<iLastPg );
       
-      rc = sqlite3PagerWrite(pLastPg->pDbPage);
-      if( rc==SQLITE_OK ){
-        rc = relocatePage(pBt, pLastPg, eType, iPtrPage, iFreePg, nFin!=0);
-      }
+      rc = relocatePage(pBt, pLastPg, eType, iPtrPage, iFreePg, bCommit);
       releasePage(pLastPg);
       if( rc!=SQLITE_OK ){
         return rc;
@@ -53191,29 +52661,39 @@ static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg){
     }
   }
 
-  if( nFin==0 ){
-    iLastPg--;
-    while( iLastPg==PENDING_BYTE_PAGE(pBt)||PTRMAP_ISPAGE(pBt, iLastPg) ){
-      if( PTRMAP_ISPAGE(pBt, iLastPg) ){
-        MemPage *pPg;
-        rc = btreeGetPage(pBt, iLastPg, &pPg, 0);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-        rc = sqlite3PagerWrite(pPg->pDbPage);
-        releasePage(pPg);
-        if( rc!=SQLITE_OK ){
-          return rc;
-        }
-      }
+  if( bCommit==0 ){
+    do {
       iLastPg--;
-    }
-    sqlite3PagerTruncateImage(pBt->pPager, iLastPg);
+    }while( iLastPg==PENDING_BYTE_PAGE(pBt) || PTRMAP_ISPAGE(pBt, iLastPg) );
+    pBt->bDoTruncate = 1;
     pBt->nPage = iLastPg;
   }
   return SQLITE_OK;
 }
 
+/*
+** The database opened by the first argument is an auto-vacuum database
+** nOrig pages in size containing nFree free pages. Return the expected 
+** size of the database in pages following an auto-vacuum operation.
+*/
+static Pgno finalDbSize(BtShared *pBt, Pgno nOrig, Pgno nFree){
+  int nEntry;                     /* Number of entries on one ptrmap page */
+  Pgno nPtrmap;                   /* Number of PtrMap pages to be freed */
+  Pgno nFin;                      /* Return value */
+
+  nEntry = pBt->usableSize/5;
+  nPtrmap = (nFree-nOrig+PTRMAP_PAGENO(pBt, nOrig)+nEntry)/nEntry;
+  nFin = nOrig - nFree - nPtrmap;
+  if( nOrig>PENDING_BYTE_PAGE(pBt) && nFin<PENDING_BYTE_PAGE(pBt) ){
+    nFin--;
+  }
+  while( PTRMAP_ISPAGE(pBt, nFin) || nFin==PENDING_BYTE_PAGE(pBt) ){
+    nFin--;
+  }
+
+  return nFin;
+}
+
 /*
 ** A write-transaction must be opened before calling this function.
 ** It performs a single unit of work towards an incremental vacuum.
@@ -53231,11 +52711,24 @@ SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *p){
   if( !pBt->autoVacuum ){
     rc = SQLITE_DONE;
   }else{
-    invalidateAllOverflowCache(pBt);
-    rc = incrVacuumStep(pBt, 0, btreePagecount(pBt));
-    if( rc==SQLITE_OK ){
-      rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
-      put4byte(&pBt->pPage1->aData[28], pBt->nPage);
+    Pgno nOrig = btreePagecount(pBt);
+    Pgno nFree = get4byte(&pBt->pPage1->aData[36]);
+    Pgno nFin = finalDbSize(pBt, nOrig, nFree);
+
+    if( nOrig<nFin ){
+      rc = SQLITE_CORRUPT_BKPT;
+    }else if( nFree>0 ){
+      rc = saveAllCursors(pBt, 0, 0);
+      if( rc==SQLITE_OK ){
+        invalidateAllOverflowCache(pBt);
+        rc = incrVacuumStep(pBt, nFin, nOrig, 0);
+      }
+      if( rc==SQLITE_OK ){
+        rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
+        put4byte(&pBt->pPage1->aData[28], pBt->nPage);
+      }
+    }else{
+      rc = SQLITE_DONE;
     }
   }
   sqlite3BtreeLeave(p);
@@ -53244,7 +52737,7 @@ SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *p){
 
 /*
 ** This routine is called prior to sqlite3PagerCommit when a transaction
-** is commited for an auto-vacuum database.
+** is committed for an auto-vacuum database.
 **
 ** If SQLITE_OK is returned, then *pnTrunc is set to the number of pages
 ** the database file should be truncated to during the commit process. 
@@ -53262,9 +52755,7 @@ static int autoVacuumCommit(BtShared *pBt){
   if( !pBt->incrVacuum ){
     Pgno nFin;         /* Number of pages in database after autovacuuming */
     Pgno nFree;        /* Number of pages on the freelist initially */
-    Pgno nPtrmap;      /* Number of PtrMap pages to be freed */
     Pgno iFree;        /* The next page to be freed */
-    int nEntry;        /* Number of entries on one ptrmap page */
     Pgno nOrig;        /* Database size before freeing */
 
     nOrig = btreePagecount(pBt);
@@ -53277,26 +52768,20 @@ static int autoVacuumCommit(BtShared *pBt){
     }
 
     nFree = get4byte(&pBt->pPage1->aData[36]);
-    nEntry = pBt->usableSize/5;
-    nPtrmap = (nFree-nOrig+PTRMAP_PAGENO(pBt, nOrig)+nEntry)/nEntry;
-    nFin = nOrig - nFree - nPtrmap;
-    if( nOrig>PENDING_BYTE_PAGE(pBt) && nFin<PENDING_BYTE_PAGE(pBt) ){
-      nFin--;
-    }
-    while( PTRMAP_ISPAGE(pBt, nFin) || nFin==PENDING_BYTE_PAGE(pBt) ){
-      nFin--;
-    }
+    nFin = finalDbSize(pBt, nOrig, nFree);
     if( nFin>nOrig ) return SQLITE_CORRUPT_BKPT;
-
+    if( nFin<nOrig ){
+      rc = saveAllCursors(pBt, 0, 0);
+    }
     for(iFree=nOrig; iFree>nFin && rc==SQLITE_OK; iFree--){
-      rc = incrVacuumStep(pBt, nFin, iFree);
+      rc = incrVacuumStep(pBt, nFin, iFree, 1);
     }
     if( (rc==SQLITE_DONE || rc==SQLITE_OK) && nFree>0 ){
       rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
       put4byte(&pBt->pPage1->aData[32], 0);
       put4byte(&pBt->pPage1->aData[36], 0);
       put4byte(&pBt->pPage1->aData[28], nFin);
-      sqlite3PagerTruncateImage(pBt->pPager, nFin);
+      pBt->bDoTruncate = 1;
       pBt->nPage = nFin;
     }
     if( rc!=SQLITE_OK ){
@@ -53304,7 +52789,7 @@ static int autoVacuumCommit(BtShared *pBt){
     }
   }
 
-  assert( nRef==sqlite3PagerRefcount(pPager) );
+  assert( nRef>=sqlite3PagerRefcount(pPager) );
   return rc;
 }
 
@@ -53351,6 +52836,9 @@ SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree *p, const char *zMaster){
         return rc;
       }
     }
+    if( pBt->bDoTruncate ){
+      sqlite3PagerTruncateImage(pBt->pPager, pBt->nPage);
+    }
 #endif
     rc = sqlite3PagerCommitPhaseOne(pBt->pPager, zMaster, 0);
     sqlite3BtreeLeave(p);
@@ -53364,10 +52852,13 @@ SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree *p, const char *zMaster){
 */
 static void btreeEndTransaction(Btree *p){
   BtShared *pBt = p->pBt;
+  sqlite3 *db = p->db;
   assert( sqlite3BtreeHoldsMutex(p) );
 
-  btreeClearHasContent(pBt);
-  if( p->inTrans>TRANS_NONE && p->db->activeVdbeCnt>1 ){
+#ifndef SQLITE_OMIT_AUTOVACUUM
+  pBt->bDoTruncate = 0;
+#endif
+  if( p->inTrans>TRANS_NONE && db->nVdbeRead>1 ){
     /* If there are other active statements that belong to this database
     ** handle, downgrade to a read-only transaction. The other statements
     ** may still be reading from the database.  */
@@ -53441,6 +52932,7 @@ SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree *p, int bCleanup){
       return rc;
     }
     pBt->inTransaction = TRANS_READ;
+    btreeClearHasContent(pBt);
   }
 
   btreeEndTransaction(p);
@@ -53462,27 +52954,6 @@ SQLITE_PRIVATE int sqlite3BtreeCommit(Btree *p){
   return rc;
 }
 
-#ifndef NDEBUG
-/*
-** Return the number of write-cursors open on this handle. This is for use
-** in assert() expressions, so it is only compiled if NDEBUG is not
-** defined.
-**
-** For the purposes of this routine, a write-cursor is any cursor that
-** is capable of writing to the databse.  That means the cursor was
-** originally opened for writing and the cursor has not be disabled
-** by having its state changed to CURSOR_FAULT.
-*/
-static int countWriteCursors(BtShared *pBt){
-  BtCursor *pCur;
-  int r = 0;
-  for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
-    if( pCur->wrFlag && pCur->eState!=CURSOR_FAULT ) r++; 
-  }
-  return r;
-}
-#endif
-
 /*
 ** This routine sets the state to CURSOR_FAULT and the error
 ** code to errCode for every cursor on BtShared that pBtree
@@ -53562,8 +53033,9 @@ SQLITE_PRIVATE int sqlite3BtreeRollback(Btree *p, int tripCode){
       pBt->nPage = nPage;
       releasePage(pPage1);
     }
-    assert( countWriteCursors(pBt)==0 );
+    assert( countValidCursors(pBt, 1)==0 );
     pBt->inTransaction = TRANS_READ;
+    btreeClearHasContent(pBt);
   }
 
   btreeEndTransaction(p);
@@ -53988,7 +53460,7 @@ static int getOverflowPage(
 
   assert( next==0 || rc==SQLITE_DONE );
   if( rc==SQLITE_OK ){
-    rc = btreeGetPage(pBt, ovfl, &pPage, 0);
+    rc = btreeGetPage(pBt, ovfl, &pPage, (ppPage==0) ? PAGER_GET_READONLY : 0);
     assert( rc==SQLITE_OK || pPage==0 );
     if( rc==SQLITE_OK ){
       next = get4byte(pPage->aData);
@@ -54209,7 +53681,9 @@ static int accessPayload(
 
         {
           DbPage *pDbPage;
-          rc = sqlite3PagerGet(pBt->pPager, nextPage, &pDbPage);
+          rc = sqlite3PagerAcquire(pBt->pPager, nextPage, &pDbPage,
+              (eOp==0 ? PAGER_GET_READONLY : 0)
+          );
           if( rc==SQLITE_OK ){
             aPayload = sqlite3PagerGetData(pDbPage);
             nextPage = get4byte(aPayload);
@@ -54388,10 +53862,12 @@ static int moveToChild(BtCursor *pCur, u32 newPgno){
   assert( cursorHoldsMutex(pCur) );
   assert( pCur->eState==CURSOR_VALID );
   assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
+  assert( pCur->iPage>=0 );
   if( pCur->iPage>=(BTCURSOR_MAX_DEPTH-1) ){
     return SQLITE_CORRUPT_BKPT;
   }
-  rc = getAndInitPage(pBt, newPgno, &pNewPage);
+  rc = getAndInitPage(pBt, newPgno, &pNewPage,
+               pCur->wrFlag==0 ? PAGER_GET_READONLY : 0);
   if( rc ) return rc;
   pCur->apPage[i+1] = pNewPage;
   pCur->aiIdx[i+1] = 0;
@@ -54508,7 +53984,8 @@ static int moveToRoot(BtCursor *pCur){
     pCur->eState = CURSOR_INVALID;
     return SQLITE_OK;
   }else{
-    rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0]);
+    rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0],
+                        pCur->wrFlag==0 ? PAGER_GET_READONLY : 0);
     if( rc!=SQLITE_OK ){
       pCur->eState = CURSOR_INVALID;
       return rc;
@@ -54903,21 +54380,29 @@ SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
   MemPage *pPage;
 
   assert( cursorHoldsMutex(pCur) );
-  rc = restoreCursorPosition(pCur);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
   assert( pRes!=0 );
-  if( CURSOR_INVALID==pCur->eState ){
-    *pRes = 1;
-    return SQLITE_OK;
+  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
+  if( pCur->eState!=CURSOR_VALID ){
+    rc = restoreCursorPosition(pCur);
+    if( rc!=SQLITE_OK ){
+      *pRes = 0;
+      return rc;
+    }
+    if( CURSOR_INVALID==pCur->eState ){
+      *pRes = 1;
+      return SQLITE_OK;
+    }
+    if( pCur->skipNext ){
+      assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
+      pCur->eState = CURSOR_VALID;
+      if( pCur->skipNext>0 ){
+        pCur->skipNext = 0;
+        *pRes = 0;
+        return SQLITE_OK;
+      }
+      pCur->skipNext = 0;
+    }
   }
-  if( pCur->skipNext>0 ){
-    pCur->skipNext = 0;
-    *pRes = 0;
-    return SQLITE_OK;
-  }
-  pCur->skipNext = 0;
 
   pPage = pCur->apPage[pCur->iPage];
   idx = ++pCur->aiIdx[pCur->iPage];
@@ -54935,7 +54420,10 @@ SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
   if( idx>=pPage->nCell ){
     if( !pPage->leaf ){
       rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
-      if( rc ) return rc;
+      if( rc ){
+        *pRes = 0;
+        return rc;
+      }
       rc = moveToLeftmost(pCur);
       *pRes = 0;
       return rc;
@@ -54977,21 +54465,32 @@ SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
   MemPage *pPage;
 
   assert( cursorHoldsMutex(pCur) );
-  rc = restoreCursorPosition(pCur);
-  if( rc!=SQLITE_OK ){
-    return rc;
-  }
+  assert( pRes!=0 );
+  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
   pCur->atLast = 0;
-  if( CURSOR_INVALID==pCur->eState ){
-    *pRes = 1;
-    return SQLITE_OK;
+  if( pCur->eState!=CURSOR_VALID ){
+    if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
+      rc = btreeRestoreCursorPosition(pCur);
+      if( rc!=SQLITE_OK ){
+        *pRes = 0;
+        return rc;
+      }
+    }
+    if( CURSOR_INVALID==pCur->eState ){
+      *pRes = 1;
+      return SQLITE_OK;
+    }
+    if( pCur->skipNext ){
+      assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
+      pCur->eState = CURSOR_VALID;
+      if( pCur->skipNext<0 ){
+        pCur->skipNext = 0;
+        *pRes = 0;
+        return SQLITE_OK;
+      }
+      pCur->skipNext = 0;
+    }
   }
-  if( pCur->skipNext<0 ){
-    pCur->skipNext = 0;
-    *pRes = 0;
-    return SQLITE_OK;
-  }
-  pCur->skipNext = 0;
 
   pPage = pCur->apPage[pCur->iPage];
   assert( pPage->isInit );
@@ -54999,6 +54498,7 @@ SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
     int idx = pCur->aiIdx[pCur->iPage];
     rc = moveToChild(pCur, get4byte(findCell(pPage, idx)));
     if( rc ){
+      *pRes = 0;
       return rc;
     }
     rc = moveToRightmost(pCur);
@@ -55038,21 +54538,23 @@ SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
 ** an error.  *ppPage and *pPgno are undefined in the event of an error.
 ** Do not invoke sqlite3PagerUnref() on *ppPage if an error is returned.
 **
-** If the "nearby" parameter is not 0, then a (feeble) effort is made to 
+** If the "nearby" parameter is not 0, then an effort is made to 
 ** locate a page close to the page number "nearby".  This can be used in an
 ** attempt to keep related pages close to each other in the database file,
 ** which in turn can make database access faster.
 **
-** If the "exact" parameter is not 0, and the page-number nearby exists 
-** anywhere on the free-list, then it is guarenteed to be returned. This
-** is only used by auto-vacuum databases when allocating a new table.
+** If the eMode parameter is BTALLOC_EXACT and the nearby page exists
+** anywhere on the free-list, then it is guaranteed to be returned.  If
+** eMode is BTALLOC_LT then the page returned will be less than or equal
+** to nearby if any such page exists.  If eMode is BTALLOC_ANY then there
+** are no restrictions on which page is returned.
 */
 static int allocateBtreePage(
-  BtShared *pBt, 
-  MemPage **ppPage, 
-  Pgno *pPgno, 
-  Pgno nearby,
-  u8 exact
+  BtShared *pBt,         /* The btree */
+  MemPage **ppPage,      /* Store pointer to the allocated page here */
+  Pgno *pPgno,           /* Store the page number here */
+  Pgno nearby,           /* Search for a page near this one */
+  u8 eMode               /* BTALLOC_EXACT, BTALLOC_LT, or BTALLOC_ANY */
 ){
   MemPage *pPage1;
   int rc;
@@ -55063,6 +54565,7 @@ static int allocateBtreePage(
   Pgno mxPage;     /* Total size of the database file */
 
   assert( sqlite3_mutex_held(pBt->mutex) );
+  assert( eMode==BTALLOC_ANY || (nearby>0 && IfNotOmitAV(pBt->autoVacuum)) );
   pPage1 = pBt->pPage1;
   mxPage = btreePagecount(pBt);
   n = get4byte(&pPage1->aData[36]);
@@ -55075,21 +54578,24 @@ static int allocateBtreePage(
     Pgno iTrunk;
     u8 searchList = 0; /* If the free-list must be searched for 'nearby' */
     
-    /* If the 'exact' parameter was true and a query of the pointer-map
+    /* If eMode==BTALLOC_EXACT and a query of the pointer-map
     ** shows that the page 'nearby' is somewhere on the free-list, then
     ** the entire-list will be searched for that page.
     */
 #ifndef SQLITE_OMIT_AUTOVACUUM
-    if( exact && nearby<=mxPage ){
-      u8 eType;
-      assert( nearby>0 );
-      assert( pBt->autoVacuum );
-      rc = ptrmapGet(pBt, nearby, &eType, 0);
-      if( rc ) return rc;
-      if( eType==PTRMAP_FREEPAGE ){
-        searchList = 1;
+    if( eMode==BTALLOC_EXACT ){
+      if( nearby<=mxPage ){
+        u8 eType;
+        assert( nearby>0 );
+        assert( pBt->autoVacuum );
+        rc = ptrmapGet(pBt, nearby, &eType, 0);
+        if( rc ) return rc;
+        if( eType==PTRMAP_FREEPAGE ){
+          searchList = 1;
+        }
       }
-      *pPgno = nearby;
+    }else if( eMode==BTALLOC_LE ){
+      searchList = 1;
     }
 #endif
 
@@ -55102,7 +54608,8 @@ static int allocateBtreePage(
 
     /* The code within this loop is run only once if the 'searchList' variable
     ** is not true. Otherwise, it runs once for each trunk-page on the
-    ** free-list until the page 'nearby' is located.
+    ** free-list until the page 'nearby' is located (eMode==BTALLOC_EXACT)
+    ** or until a page less than 'nearby' is located (eMode==BTALLOC_LT)
     */
     do {
       pPrevTrunk = pTrunk;
@@ -55144,11 +54651,13 @@ static int allocateBtreePage(
         rc = SQLITE_CORRUPT_BKPT;
         goto end_allocate_page;
 #ifndef SQLITE_OMIT_AUTOVACUUM
-      }else if( searchList && nearby==iTrunk ){
+      }else if( searchList 
+            && (nearby==iTrunk || (iTrunk<nearby && eMode==BTALLOC_LE)) 
+      ){
         /* The list is being searched and this trunk page is the page
         ** to allocate, regardless of whether it has leaves.
         */
-        assert( *pPgno==iTrunk );
+        *pPgno = iTrunk;
         *ppPage = pTrunk;
         searchList = 0;
         rc = sqlite3PagerWrite(pTrunk->pDbPage);
@@ -55211,14 +54720,24 @@ static int allocateBtreePage(
         unsigned char *aData = pTrunk->aData;
         if( nearby>0 ){
           u32 i;
-          int dist;
           closest = 0;
-          dist = sqlite3AbsInt32(get4byte(&aData[8]) - nearby);
-          for(i=1; i<k; i++){
-            int d2 = sqlite3AbsInt32(get4byte(&aData[8+i*4]) - nearby);
-            if( d2<dist ){
-              closest = i;
-              dist = d2;
+          if( eMode==BTALLOC_LE ){
+            for(i=0; i<k; i++){
+              iPage = get4byte(&aData[8+i*4]);
+              if( iPage<=nearby ){
+                closest = i;
+                break;
+              }
+            }
+          }else{
+            int dist;
+            dist = sqlite3AbsInt32(get4byte(&aData[8]) - nearby);
+            for(i=1; i<k; i++){
+              int d2 = sqlite3AbsInt32(get4byte(&aData[8+i*4]) - nearby);
+              if( d2<dist ){
+                closest = i;
+                dist = d2;
+              }
             }
           }
         }else{
@@ -55232,7 +54751,9 @@ static int allocateBtreePage(
           goto end_allocate_page;
         }
         testcase( iPage==mxPage );
-        if( !searchList || iPage==nearby ){
+        if( !searchList 
+         || (iPage==nearby || (iPage<nearby && eMode==BTALLOC_LE)) 
+        ){
           int noContent;
           *pPgno = iPage;
           TRACE(("ALLOCATE: %d was leaf %d of %d on trunk %d"
@@ -55244,7 +54765,7 @@ static int allocateBtreePage(
             memcpy(&aData[8+closest*4], &aData[4+k*4], 4);
           }
           put4byte(&aData[4], k-1);
-          noContent = !btreeGetHasContent(pBt, *pPgno);
+          noContent = !btreeGetHasContent(pBt, *pPgno) ? PAGER_GET_NOCONTENT : 0;
           rc = btreeGetPage(pBt, *pPgno, ppPage, noContent);
           if( rc==SQLITE_OK ){
             rc = sqlite3PagerWrite((*ppPage)->pDbPage);
@@ -55259,8 +54780,26 @@ static int allocateBtreePage(
       pPrevTrunk = 0;
     }while( searchList );
   }else{
-    /* There are no pages on the freelist, so create a new page at the
-    ** end of the file */
+    /* There are no pages on the freelist, so append a new page to the
+    ** database image.
+    **
+    ** Normally, new pages allocated by this block can be requested from the
+    ** pager layer with the 'no-content' flag set. This prevents the pager
+    ** from trying to read the pages content from disk. However, if the
+    ** current transaction has already run one or more incremental-vacuum
+    ** steps, then the page we are about to allocate may contain content
+    ** that is required in the event of a rollback. In this case, do
+    ** not set the no-content flag. This causes the pager to load and journal
+    ** the current page content before overwriting it.
+    **
+    ** Note that the pager will not actually attempt to load or journal 
+    ** content for any page that really does lie past the end of the database
+    ** file on disk. So the effects of disabling the no-content optimization
+    ** here are confined to those pages that lie between the end of the
+    ** database image and the end of the database file.
+    */
+    int bNoContent = (0==IfNotOmitAV(pBt->bDoTruncate)) ? PAGER_GET_NOCONTENT : 0;
+
     rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
     if( rc ) return rc;
     pBt->nPage++;
@@ -55275,7 +54814,7 @@ static int allocateBtreePage(
       MemPage *pPg = 0;
       TRACE(("ALLOCATE: %d from end of file (pointer-map page)\n", pBt->nPage));
       assert( pBt->nPage!=PENDING_BYTE_PAGE(pBt) );
-      rc = btreeGetPage(pBt, pBt->nPage, &pPg, 1);
+      rc = btreeGetPage(pBt, pBt->nPage, &pPg, bNoContent);
       if( rc==SQLITE_OK ){
         rc = sqlite3PagerWrite(pPg->pDbPage);
         releasePage(pPg);
@@ -55289,7 +54828,7 @@ static int allocateBtreePage(
     *pPgno = pBt->nPage;
 
     assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );
-    rc = btreeGetPage(pBt, *pPgno, ppPage, 1);
+    rc = btreeGetPage(pBt, *pPgno, ppPage, bNoContent);
     if( rc ) return rc;
     rc = sqlite3PagerWrite((*ppPage)->pDbPage);
     if( rc!=SQLITE_OK ){
@@ -55473,7 +55012,7 @@ static int clearCell(MemPage *pPage, unsigned char *pCell){
     return SQLITE_OK;  /* No overflow pages. Return without doing anything */
   }
   if( pCell+info.iOverflow+3 > pPage->aData+pPage->maskPage ){
-    return SQLITE_CORRUPT;  /* Cell extends past end of page */
+    return SQLITE_CORRUPT_BKPT;  /* Cell extends past end of page */
   }
   ovflPgno = get4byte(&pCell[info.iOverflow]);
   assert( pBt->usableSize > 4 );
@@ -55617,7 +55156,7 @@ static int fillInCell(
       ** If this is the first overflow page, then write a partial entry 
       ** to the pointer-map. If we write nothing to this pointer-map slot,
       ** then the optimistic overflow chain processing in clearCell()
-      ** may misinterpret the uninitialised values and delete the
+      ** may misinterpret the uninitialized values and delete the
       ** wrong pages from the database.
       */
       if( pBt->autoVacuum && rc==SQLITE_OK ){
@@ -55929,7 +55468,7 @@ static int balance_quick(MemPage *pParent, MemPage *pPage, u8 *pSpace){
   assert( pPage->nOverflow==1 );
 
   /* This error condition is now caught prior to reaching this function */
-  if( pPage->nCell<=0 ) return SQLITE_CORRUPT_BKPT;
+  if( pPage->nCell==0 ) return SQLITE_CORRUPT_BKPT;
 
   /* Allocate a new page. This page will become the right-sibling of 
   ** pPage. Make the parent page writable, so that the new divider cell
@@ -56139,11 +55678,15 @@ static void copyNodeContent(MemPage *pFrom, MemPage *pTo, int *pRC){
 ** If aOvflSpace is set to a null pointer, this function returns 
 ** SQLITE_NOMEM.
 */
+#if defined(_MSC_VER) && _MSC_VER >= 1700 && defined(_M_ARM)
+#pragma optimize("", off)
+#endif
 static int balance_nonroot(
   MemPage *pParent,               /* Parent page of siblings being balanced */
   int iParentIdx,                 /* Index of "the page" in pParent */
   u8 *aOvflSpace,                 /* page-size bytes of space for parent ovfl */
-  int isRoot                      /* True if pParent is a root-page */
+  int isRoot,                     /* True if pParent is a root-page */
+  int bBulk                       /* True if this call is part of a bulk load */
 ){
   BtShared *pBt;               /* The whole database */
   int nCell = 0;               /* Number of cells in apCell[] */
@@ -56207,18 +55750,19 @@ static int balance_nonroot(
   i = pParent->nOverflow + pParent->nCell;
   if( i<2 ){
     nxDiv = 0;
-    nOld = i+1;
   }else{
-    nOld = 3;
+    assert( bBulk==0 || bBulk==1 );
     if( iParentIdx==0 ){                 
       nxDiv = 0;
     }else if( iParentIdx==i ){
-      nxDiv = i-2;
+      nxDiv = i-2+bBulk;
     }else{
+      assert( bBulk==0 );
       nxDiv = iParentIdx-1;
     }
-    i = 2;
+    i = 2-bBulk;
   }
+  nOld = i+1;
   if( (i+nxDiv-pParent->nOverflow)==pParent->nCell ){
     pRight = &pParent->aData[pParent->hdrOffset+8];
   }else{
@@ -56226,7 +55770,7 @@ static int balance_nonroot(
   }
   pgno = get4byte(pRight);
   while( 1 ){
-    rc = getAndInitPage(pBt, pgno, &apOld[i]);
+    rc = getAndInitPage(pBt, pgno, &apOld[i], 0);
     if( rc ){
       memset(apOld, 0, (i+1)*sizeof(MemPage*));
       goto balance_cleanup;
@@ -56298,7 +55842,7 @@ static int balance_nonroot(
   /*
   ** Load pointers to all cells on sibling pages and the divider cells
   ** into the local apCell[] array.  Make copies of the divider cells
-  ** into space obtained from aSpace1[] and remove the the divider Cells
+  ** into space obtained from aSpace1[] and remove the divider cells
   ** from pParent.
   **
   ** If the siblings are on leaf pages, then the child pointers of the
@@ -56427,7 +55971,9 @@ static int balance_nonroot(
     d = r + 1 - leafData;
     assert( d<nMaxCells );
     assert( r<nMaxCells );
-    while( szRight==0 || szRight+szCell[d]+2<=szLeft-(szCell[r]+2) ){
+    while( szRight==0 
+       || (!bBulk && szRight+szCell[d]+2<=szLeft-(szCell[r]+2)) 
+    ){
       szRight += szCell[d] + 2;
       szLeft -= szCell[r] + 2;
       cntNew[i-1]--;
@@ -56474,7 +56020,7 @@ static int balance_nonroot(
       if( rc ) goto balance_cleanup;
     }else{
       assert( i>0 );
-      rc = allocateBtreePage(pBt, &pNew, &pgno, pgno, 0);
+      rc = allocateBtreePage(pBt, &pNew, &pgno, (bBulk ? 1 : pgno), 0);
       if( rc ) goto balance_cleanup;
       apNew[i] = pNew;
       nNew++;
@@ -56686,6 +56232,7 @@ static int balance_nonroot(
         ** sibling page j. If the siblings are not leaf pages of an
         ** intkey b-tree, then cell i was a divider cell. */
         assert( j+1 < ArraySize(apCopy) );
+        assert( j+1 < nOld );
         pOld = apCopy[++j];
         iNextOld = i + !leafData + pOld->nCell + pOld->nOverflow;
         if( pOld->nOverflow ){
@@ -56764,6 +56311,9 @@ balance_cleanup:
 
   return rc;
 }
+#if defined(_MSC_VER) && _MSC_VER >= 1700 && defined(_M_ARM)
+#pragma optimize("", on)
+#endif
 
 
 /*
@@ -56924,7 +56474,7 @@ static int balance(BtCursor *pCur){
           ** pSpace buffer passed to the latter call to balance_nonroot().
           */
           u8 *pSpace = sqlite3PageMalloc(pCur->pBt->pageSize);
-          rc = balance_nonroot(pParent, iIdx, pSpace, iPage==1);
+          rc = balance_nonroot(pParent, iIdx, pSpace, iPage==1, pCur->hints);
           if( pFree ){
             /* If pFree is not NULL, it points to the pSpace buffer used 
             ** by a previous call to balance_nonroot(). Its contents are
@@ -57079,7 +56629,7 @@ SQLITE_PRIVATE int sqlite3BtreeInsert(
   insertCell(pPage, idx, newCell, szNew, 0, 0, &rc);
   assert( rc!=SQLITE_OK || pPage->nCell>0 || pPage->nOverflow>0 );
 
-  /* If no error has occured and pPage has an overflow cell, call balance() 
+  /* If no error has occurred and pPage has an overflow cell, call balance() 
   ** to redistribute the cells within the tree. Since balance() may move
   ** the cursor, zero the BtCursor.info.nSize and BtCursor.validNKey
   ** variables.
@@ -57293,7 +56843,7 @@ static int btreeCreateTable(Btree *p, int *piTable, int createTabFlags){
     ** be moved to the allocated page (unless the allocated page happens
     ** to reside at pgnoRoot).
     */
-    rc = allocateBtreePage(pBt, &pPageMove, &pgnoMove, pgnoRoot, 1);
+    rc = allocateBtreePage(pBt, &pPageMove, &pgnoMove, pgnoRoot, BTALLOC_EXACT);
     if( rc!=SQLITE_OK ){
       return rc;
     }
@@ -57308,7 +56858,14 @@ static int btreeCreateTable(Btree *p, int *piTable, int createTabFlags){
       u8 eType = 0;
       Pgno iPtrPage = 0;
 
+      /* Save the positions of any open cursors. This is required in
+      ** case they are holding a reference to an xFetch reference
+      ** corresponding to page pgnoRoot.  */
+      rc = saveAllCursors(pBt, 0, 0);
       releasePage(pPageMove);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
 
       /* Move the page currently at pgnoRoot to pgnoMove. */
       rc = btreeGetPage(pBt, pgnoRoot, &pRoot, 0);
@@ -57408,7 +56965,7 @@ static int clearDatabasePage(
     return SQLITE_CORRUPT_BKPT;
   }
 
-  rc = getAndInitPage(pBt, pgno, &pPage);
+  rc = getAndInitPage(pBt, pgno, &pPage, 0);
   if( rc ) return rc;
   for(i=0; i<pPage->nCell; i++){
     pCell = findCell(pPage, i);
@@ -57770,7 +57327,7 @@ static void checkAppendMsg(
   }
   sqlite3VXPrintf(&pCheck->errMsg, 1, zFormat, ap);
   va_end(ap);
-  if( pCheck->errMsg.mallocFailed ){
+  if( pCheck->errMsg.accError==STRACCUM_NOMEM ){
     pCheck->mallocFailed = 1;
   }
 }
@@ -58200,7 +57757,7 @@ SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(
   }
   i = PENDING_BYTE_PAGE(pBt);
   if( i<=sCheck.nPage ) setPageReferenced(&sCheck, i);
-  sqlite3StrAccumInit(&sCheck.errMsg, zErr, sizeof(zErr), 20000);
+  sqlite3StrAccumInit(&sCheck.errMsg, zErr, sizeof(zErr), SQLITE_MAX_LENGTH);
   sCheck.errMsg.useMalloc = 2;
 
   /* Check the integrity of the freelist
@@ -58439,6 +57996,17 @@ SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void
     return SQLITE_ABORT;
   }
 
+  /* Save the positions of all other cursors open on this table. This is
+  ** required in case any of them are holding references to an xFetch
+  ** version of the b-tree page modified by the accessPayload call below.
+  **
+  ** Note that pCsr must be open on a BTREE_INTKEY table and saveCursorPosition()
+  ** and hence saveAllCursors() cannot fail on a BTREE_INTKEY table, hence
+  ** saveAllCursors can only return SQLITE_OK.
+  */
+  VVA_ONLY(rc =) saveAllCursors(pCsr->pBt, pCsr->pgnoRoot, pCsr);
+  assert( rc==SQLITE_OK );
+
   /* Check some assumptions: 
   **   (a) the cursor is open for writing,
   **   (b) there is a read/write transaction open,
@@ -58512,6 +58080,15 @@ SQLITE_PRIVATE int sqlite3BtreeSetVersion(Btree *pBtree, int iVersion){
   return rc;
 }
 
+/*
+** set the mask of hint flags for cursor pCsr. Currently the only valid
+** values are 0 and BTREE_BULKLOAD.
+*/
+SQLITE_PRIVATE void sqlite3BtreeCursorHints(BtCursor *pCsr, unsigned int mask){
+  assert( mask==BTREE_BULKLOAD || mask==0 );
+  pCsr->hints = mask;
+}
+
 /************** End of btree.c ***********************************************/
 /************** Begin file backup.c ******************************************/
 /*
@@ -58529,12 +58106,6 @@ SQLITE_PRIVATE int sqlite3BtreeSetVersion(Btree *pBtree, int iVersion){
 ** API functions and the related features.
 */
 
-/* Macro to find the minimum of two numeric values.
-*/
-#ifndef MIN
-# define MIN(x,y) ((x)<(y)?(x):(y))
-#endif
-
 /*
 ** Structure allocated for each backup operation.
 */
@@ -58678,7 +58249,7 @@ SQLITE_API sqlite3_backup *sqlite3_backup_init(
     ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
     ** call to sqlite3_backup_init() and is destroyed by a call to
     ** sqlite3_backup_finish(). */
-    p = (sqlite3_backup *)sqlite3_malloc(sizeof(sqlite3_backup));
+    p = (sqlite3_backup *)sqlite3MallocZero(sizeof(sqlite3_backup));
     if( !p ){
       sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
     }
@@ -58686,7 +58257,6 @@ SQLITE_API sqlite3_backup *sqlite3_backup_init(
 
   /* If the allocation succeeded, populate the new object. */
   if( p ){
-    memset(p, 0, sizeof(sqlite3_backup));
     p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
     p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
     p->pDestDb = pDestDb;
@@ -58727,20 +58297,28 @@ static int isFatalError(int rc){
 ** page iSrcPg from the source database. Copy this data into the 
 ** destination database.
 */
-static int backupOnePage(sqlite3_backup *p, Pgno iSrcPg, const u8 *zSrcData){
+static int backupOnePage(
+  sqlite3_backup *p,              /* Backup handle */
+  Pgno iSrcPg,                    /* Source database page to backup */
+  const u8 *zSrcData,             /* Source database page data */
+  int bUpdate                     /* True for an update, false otherwise */
+){
   Pager * const pDestPager = sqlite3BtreePager(p->pDest);
   const int nSrcPgsz = sqlite3BtreeGetPageSize(p->pSrc);
   int nDestPgsz = sqlite3BtreeGetPageSize(p->pDest);
   const int nCopy = MIN(nSrcPgsz, nDestPgsz);
   const i64 iEnd = (i64)iSrcPg*(i64)nSrcPgsz;
 #ifdef SQLITE_HAS_CODEC
-  int nSrcReserve = sqlite3BtreeGetReserve(p->pSrc);
+  /* Use BtreeGetReserveNoMutex() for the source b-tree, as although it is
+  ** guaranteed that the shared-mutex is held by this thread, handle
+  ** p->pSrc may not actually be the owner.  */
+  int nSrcReserve = sqlite3BtreeGetReserveNoMutex(p->pSrc);
   int nDestReserve = sqlite3BtreeGetReserve(p->pDest);
 #endif
-
   int rc = SQLITE_OK;
   i64 iOff;
 
+  assert( sqlite3BtreeGetReserveNoMutex(p->pSrc)>=0 );
   assert( p->bDestLocked );
   assert( !isFatalError(p->rc) );
   assert( iSrcPg!=PENDING_BYTE_PAGE(p->pSrc->pBt) );
@@ -58797,6 +58375,9 @@ static int backupOnePage(sqlite3_backup *p, Pgno iSrcPg, const u8 *zSrcData){
       */
       memcpy(zOut, zIn, nCopy);
       ((u8 *)sqlite3PagerGetExtra(pDestPg))[0] = 0;
+      if( iOff==0 && bUpdate==0 ){
+        sqlite3Put4byte(&zOut[28], sqlite3BtreeLastPage(p->pSrc));
+      }
     }
     sqlite3PagerUnref(pDestPg);
   }
@@ -58901,9 +58482,10 @@ SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage){
       const Pgno iSrcPg = p->iNext;                 /* Source page number */
       if( iSrcPg!=PENDING_BYTE_PAGE(p->pSrc->pBt) ){
         DbPage *pSrcPg;                             /* Source page object */
-        rc = sqlite3PagerGet(pSrcPager, iSrcPg, &pSrcPg);
+        rc = sqlite3PagerAcquire(pSrcPager, iSrcPg, &pSrcPg,
+                                 PAGER_GET_READONLY);
         if( rc==SQLITE_OK ){
-          rc = backupOnePage(p, iSrcPg, sqlite3PagerGetData(pSrcPg));
+          rc = backupOnePage(p, iSrcPg, sqlite3PagerGetData(pSrcPg), 0);
           sqlite3PagerUnref(pSrcPg);
         }
       }
@@ -58925,7 +58507,13 @@ SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage){
     ** same schema version.
     */
     if( rc==SQLITE_DONE ){
-      rc = sqlite3BtreeUpdateMeta(p->pDest,1,p->iDestSchema+1);
+      if( nSrcPage==0 ){
+        rc = sqlite3BtreeNewDb(p->pDest);
+        nSrcPage = 1;
+      }
+      if( rc==SQLITE_OK || rc==SQLITE_DONE ){
+        rc = sqlite3BtreeUpdateMeta(p->pDest,1,p->iDestSchema+1);
+      }
       if( rc==SQLITE_OK ){
         if( p->pDestDb ){
           sqlite3ResetAllSchemasOfConnection(p->pDestDb);
@@ -58959,7 +58547,7 @@ SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage){
         }else{
           nDestTruncate = nSrcPage * (pgszSrc/pgszDest);
         }
-        sqlite3PagerTruncateImage(pDestPager, nDestTruncate);
+        assert( nDestTruncate>0 );
 
         if( pgszSrc<pgszDest ){
           /* If the source page-size is smaller than the destination page-size,
@@ -58973,22 +58561,38 @@ SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage){
           */
           const i64 iSize = (i64)pgszSrc * (i64)nSrcPage;
           sqlite3_file * const pFile = sqlite3PagerFile(pDestPager);
+          Pgno iPg;
+          int nDstPage;
           i64 iOff;
           i64 iEnd;
 
           assert( pFile );
-          assert( (i64)nDestTruncate*(i64)pgszDest >= iSize || (
+          assert( nDestTruncate==0 
+              || (i64)nDestTruncate*(i64)pgszDest >= iSize || (
                 nDestTruncate==(int)(PENDING_BYTE_PAGE(p->pDest->pBt)-1)
              && iSize>=PENDING_BYTE && iSize<=PENDING_BYTE+pgszDest
           ));
 
-          /* This call ensures that all data required to recreate the original
+          /* This block ensures that all data required to recreate the original
           ** database has been stored in the journal for pDestPager and the
           ** journal synced to disk. So at this point we may safely modify
           ** the database file in any way, knowing that if a power failure
           ** occurs, the original database will be reconstructed from the 
           ** journal file.  */
-          rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 1);
+          sqlite3PagerPagecount(pDestPager, &nDstPage);
+          for(iPg=nDestTruncate; rc==SQLITE_OK && iPg<=(Pgno)nDstPage; iPg++){
+            if( iPg!=PENDING_BYTE_PAGE(p->pDest->pBt) ){
+              DbPage *pPg;
+              rc = sqlite3PagerGet(pDestPager, iPg, &pPg);
+              if( rc==SQLITE_OK ){
+                rc = sqlite3PagerWrite(pPg);
+                sqlite3PagerUnref(pPg);
+              }
+            }
+          }
+          if( rc==SQLITE_OK ){
+            rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 1);
+          }
 
           /* Write the extra pages and truncate the database file as required */
           iEnd = MIN(PENDING_BYTE + pgszDest, iSize);
@@ -59015,6 +58619,7 @@ SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage){
             rc = sqlite3PagerSync(pDestPager);
           }
         }else{
+          sqlite3PagerTruncateImage(pDestPager, nDestTruncate);
           rc = sqlite3PagerCommitPhaseOne(pDestPager, 0, 0);
         }
     
@@ -59057,14 +58662,14 @@ SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage){
 */
 SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p){
   sqlite3_backup **pp;                 /* Ptr to head of pagers backup list */
-  MUTEX_LOGIC( sqlite3_mutex *mutex; ) /* Mutex to protect source database */
+  sqlite3 *pSrcDb;                     /* Source database connection */
   int rc;                              /* Value to return */
 
   /* Enter the mutexes */
   if( p==0 ) return SQLITE_OK;
-  sqlite3_mutex_enter(p->pSrcDb->mutex);
+  pSrcDb = p->pSrcDb;
+  sqlite3_mutex_enter(pSrcDb->mutex);
   sqlite3BtreeEnter(p->pSrc);
-  MUTEX_LOGIC( mutex = p->pSrcDb->mutex; )
   if( p->pDestDb ){
     sqlite3_mutex_enter(p->pDestDb->mutex);
   }
@@ -59090,7 +58695,7 @@ SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p){
 
   /* Exit the mutexes and free the backup context structure. */
   if( p->pDestDb ){
-    sqlite3_mutex_leave(p->pDestDb->mutex);
+    sqlite3LeaveMutexAndCloseZombie(p->pDestDb);
   }
   sqlite3BtreeLeave(p->pSrc);
   if( p->pDestDb ){
@@ -59099,7 +58704,7 @@ SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p){
     ** sqlite3_backup_finish(). */
     sqlite3_free(p);
   }
-  sqlite3_mutex_leave(mutex);
+  sqlite3LeaveMutexAndCloseZombie(pSrcDb);
   return rc;
 }
 
@@ -59143,7 +58748,7 @@ SQLITE_PRIVATE void sqlite3BackupUpdate(sqlite3_backup *pBackup, Pgno iPage, con
       int rc;
       assert( p->pDestDb );
       sqlite3_mutex_enter(p->pDestDb->mutex);
-      rc = backupOnePage(p, iPage, aData);
+      rc = backupOnePage(p, iPage, aData, 1);
       sqlite3_mutex_leave(p->pDestDb->mutex);
       assert( rc!=SQLITE_BUSY && rc!=SQLITE_LOCKED );
       if( rc!=SQLITE_OK ){
@@ -59266,7 +58871,9 @@ copy_finished:
 ** between formats.
 */
 SQLITE_PRIVATE int sqlite3VdbeChangeEncoding(Mem *pMem, int desiredEnc){
+#ifndef SQLITE_OMIT_UTF16
   int rc;
+#endif
   assert( (pMem->flags&MEM_RowSet)==0 );
   assert( desiredEnc==SQLITE_UTF8 || desiredEnc==SQLITE_UTF16LE
            || desiredEnc==SQLITE_UTF16BE );
@@ -60031,34 +59638,29 @@ SQLITE_PRIVATE int sqlite3MemCompare(const Mem *pMem1, const Mem *pMem2, const C
   ** if both values are integers.
   */
   if( combined_flags&(MEM_Int|MEM_Real) ){
-    if( !(f1&(MEM_Int|MEM_Real)) ){
-      return 1;
-    }
-    if( !(f2&(MEM_Int|MEM_Real)) ){
-      return -1;
-    }
-    if( (f1 & f2 & MEM_Int)==0 ){
-      double r1, r2;
-      if( (f1&MEM_Real)==0 ){
-        r1 = (double)pMem1->u.i;
-      }else{
-        r1 = pMem1->r;
-      }
-      if( (f2&MEM_Real)==0 ){
-        r2 = (double)pMem2->u.i;
-      }else{
-        r2 = pMem2->r;
-      }
-      if( r1<r2 ) return -1;
-      if( r1>r2 ) return 1;
-      return 0;
-    }else{
-      assert( f1&MEM_Int );
-      assert( f2&MEM_Int );
+    double r1, r2;
+    if( (f1 & f2 & MEM_Int)!=0 ){
       if( pMem1->u.i < pMem2->u.i ) return -1;
       if( pMem1->u.i > pMem2->u.i ) return 1;
       return 0;
     }
+    if( (f1&MEM_Real)!=0 ){
+      r1 = pMem1->r;
+    }else if( (f1&MEM_Int)!=0 ){
+      r1 = (double)pMem1->u.i;
+    }else{
+      return 1;
+    }
+    if( (f2&MEM_Real)!=0 ){
+      r2 = pMem2->r;
+    }else if( (f2&MEM_Int)!=0 ){
+      r2 = (double)pMem2->u.i;
+    }else{
+      return -1;
+    }
+    if( r1<r2 ) return -1;
+    if( r1>r2 ) return 1;
+    return 0;
   }
 
   /* If one value is a string and the other is a blob, the string is less.
@@ -60411,18 +60013,6 @@ SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){
 ** But that file was getting too big so this subroutines were split out.
 */
 
-
-
-/*
-** When debugging the code generator in a symbolic debugger, one can
-** set the sqlite3VdbeAddopTrace to 1 and all opcodes will be printed
-** as they are added to the instruction stream.
-*/
-#ifdef SQLITE_DEBUG
-SQLITE_PRIVATE int sqlite3VdbeAddopTrace = 0;
-#endif
-
-
 /*
 ** Create a new virtual database engine.
 */
@@ -60447,7 +60037,7 @@ SQLITE_PRIVATE Vdbe *sqlite3VdbeCreate(sqlite3 *db){
 SQLITE_PRIVATE void sqlite3VdbeSetSql(Vdbe *p, const char *z, int n, int isPrepareV2){
   assert( isPrepareV2==1 || isPrepareV2==0 );
   if( p==0 ) return;
-#ifdef SQLITE_OMIT_TRACE
+#if defined(SQLITE_OMIT_TRACE) && !defined(SQLITE_ENABLE_SQLLOG)
   if( !isPrepareV2 ) return;
 #endif
   assert( p->zSql==0 );
@@ -60552,7 +60142,9 @@ SQLITE_PRIVATE int sqlite3VdbeAddOp3(Vdbe *p, int op, int p1, int p2, int p3){
   pOp->p4type = P4_NOTUSED;
 #ifdef SQLITE_DEBUG
   pOp->zComment = 0;
-  if( sqlite3VdbeAddopTrace ) sqlite3VdbePrintOp(0, i, &p->aOp[i]);
+  if( p->db->flags & SQLITE_VdbeAddopTrace ){
+    sqlite3VdbePrintOp(0, i, &p->aOp[i]);
+  }
 #endif
 #ifdef VDBE_PROFILE
   pOp->cycles = 0;
@@ -60654,8 +60246,8 @@ SQLITE_PRIVATE int sqlite3VdbeMakeLabel(Vdbe *p){
 SQLITE_PRIVATE void sqlite3VdbeResolveLabel(Vdbe *p, int x){
   int j = -1-x;
   assert( p->magic==VDBE_MAGIC_INIT );
-  assert( j>=0 && j<p->nLabel );
-  if( p->aLabel ){
+  assert( j<p->nLabel );
+  if( j>=0 && p->aLabel ){
     p->aLabel[j] = p->nOp;
   }
 }
@@ -60771,7 +60363,7 @@ SQLITE_PRIVATE int sqlite3VdbeAssertMayAbort(Vdbe *v, int mayAbort){
      || (opcode==OP_FkCounter && pOp->p1==0 && pOp->p2==1) 
 #endif
      || ((opcode==OP_Halt || opcode==OP_HaltIfNull) 
-      && (pOp->p1==SQLITE_CONSTRAINT && pOp->p2==OE_Abort))
+      && ((pOp->p1&0xff)==SQLITE_CONSTRAINT && pOp->p2==OE_Abort))
     ){
       hasAbort = 1;
       break;
@@ -60779,7 +60371,7 @@ SQLITE_PRIVATE int sqlite3VdbeAssertMayAbort(Vdbe *v, int mayAbort){
   }
   sqlite3DbFree(v->db, sIter.apSub);
 
-  /* Return true if hasAbort==mayAbort. Or if a malloc failure occured.
+  /* Return true if hasAbort==mayAbort. Or if a malloc failure occurred.
   ** If malloc failed, then the while() loop above may not have iterated
   ** through all opcodes and hasAbort may be set incorrectly. Return
   ** true for this case to prevent the assert() in the callers frame
@@ -60807,32 +60399,64 @@ static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs){
   Op *pOp;
   int *aLabel = p->aLabel;
   p->readOnly = 1;
+  p->bIsReader = 0;
   for(pOp=p->aOp, i=p->nOp-1; i>=0; i--, pOp++){
     u8 opcode = pOp->opcode;
 
-    pOp->opflags = sqlite3OpcodeProperty[opcode];
-    if( opcode==OP_Function || opcode==OP_AggStep ){
-      if( pOp->p5>nMaxArgs ) nMaxArgs = pOp->p5;
-    }else if( (opcode==OP_Transaction && pOp->p2!=0) || opcode==OP_Vacuum ){
-      p->readOnly = 0;
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    }else if( opcode==OP_VUpdate ){
-      if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
-    }else if( opcode==OP_VFilter ){
-      int n;
-      assert( p->nOp - i >= 3 );
-      assert( pOp[-1].opcode==OP_Integer );
-      n = pOp[-1].p1;
-      if( n>nMaxArgs ) nMaxArgs = n;
+    /* NOTE: Be sure to update mkopcodeh.awk when adding or removing
+    ** cases from this switch! */
+    switch( opcode ){
+      case OP_Function:
+      case OP_AggStep: {
+        if( pOp->p5>nMaxArgs ) nMaxArgs = pOp->p5;
+        break;
+      }
+      case OP_Transaction: {
+        if( pOp->p2!=0 ) p->readOnly = 0;
+        /* fall thru */
+      }
+      case OP_AutoCommit:
+      case OP_Savepoint: {
+        p->bIsReader = 1;
+        break;
+      }
+#ifndef SQLITE_OMIT_WAL
+      case OP_Checkpoint:
 #endif
-    }else if( opcode==OP_Next || opcode==OP_SorterNext ){
-      pOp->p4.xAdvance = sqlite3BtreeNext;
-      pOp->p4type = P4_ADVANCE;
-    }else if( opcode==OP_Prev ){
-      pOp->p4.xAdvance = sqlite3BtreePrevious;
-      pOp->p4type = P4_ADVANCE;
+      case OP_Vacuum:
+      case OP_JournalMode: {
+        p->readOnly = 0;
+        p->bIsReader = 1;
+        break;
+      }
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+      case OP_VUpdate: {
+        if( pOp->p2>nMaxArgs ) nMaxArgs = pOp->p2;
+        break;
+      }
+      case OP_VFilter: {
+        int n;
+        assert( p->nOp - i >= 3 );
+        assert( pOp[-1].opcode==OP_Integer );
+        n = pOp[-1].p1;
+        if( n>nMaxArgs ) nMaxArgs = n;
+        break;
+      }
+#endif
+      case OP_Next:
+      case OP_SorterNext: {
+        pOp->p4.xAdvance = sqlite3BtreeNext;
+        pOp->p4type = P4_ADVANCE;
+        break;
+      }
+      case OP_Prev: {
+        pOp->p4.xAdvance = sqlite3BtreePrevious;
+        pOp->p4type = P4_ADVANCE;
+        break;
+      }
     }
 
+    pOp->opflags = sqlite3OpcodeProperty[opcode];
     if( (pOp->opflags & OPFLG_JUMP)!=0 && pOp->p2<0 ){
       assert( -1-pOp->p2<p->nLabel );
       pOp->p2 = aLabel[-1-pOp->p2];
@@ -60840,8 +60464,8 @@ static void resolveP2Values(Vdbe *p, int *pMaxFuncArgs){
   }
   sqlite3DbFree(p->db, p->aLabel);
   p->aLabel = 0;
-
   *pMaxFuncArgs = nMaxArgs;
+  assert( p->bIsReader!=0 || p->btreeMask==0 );
 }
 
 /*
@@ -60906,7 +60530,7 @@ SQLITE_PRIVATE int sqlite3VdbeAddOpList(Vdbe *p, int nOp, VdbeOpList const *aOp)
       pOut->p5 = 0;
 #ifdef SQLITE_DEBUG
       pOut->zComment = 0;
-      if( sqlite3VdbeAddopTrace ){
+      if( p->db->flags & SQLITE_VdbeAddopTrace ){
         sqlite3VdbePrintOp(0, i+addr, &p->aOp[i+addr]);
       }
 #endif
@@ -60967,8 +60591,7 @@ SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe *p, u8 val){
 ** the address of the next instruction to be coded.
 */
 SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe *p, int addr){
-  assert( addr>=0 || p->db->mallocFailed );
-  if( addr>=0 ) sqlite3VdbeChangeP2(p, addr, p->nOp);
+  if( ALWAYS(addr>=0) ) sqlite3VdbeChangeP2(p, addr, p->nOp);
 }
 
 
@@ -61004,13 +60627,6 @@ static void freeP4(sqlite3 *db, int p4type, void *p4){
         if( db->pnBytesFreed==0 ) sqlite3_free(p4);
         break;
       }
-      case P4_VDBEFUNC: {
-        VdbeFunc *pVdbeFunc = (VdbeFunc *)p4;
-        freeEphemeralFunction(db, pVdbeFunc->pFunc);
-        if( db->pnBytesFreed==0 ) sqlite3VdbeDeleteAuxData(pVdbeFunc, 0);
-        sqlite3DbFree(db, pVdbeFunc);
-        break;
-      }
       case P4_FUNCDEF: {
         freeEphemeralFunction(db, (FuncDef*)p4);
         break;
@@ -61117,6 +60733,7 @@ SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int
     addr = p->nOp - 1;
   }
   pOp = &p->aOp[addr];
+  assert( pOp->p4type==P4_NOTUSED || pOp->p4type==P4_INT32 );
   freeP4(db, pOp->p4type, pOp->p4.p);
   pOp->p4.p = 0;
   if( n==P4_INT32 ){
@@ -61128,21 +60745,13 @@ SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int
     pOp->p4.p = 0;
     pOp->p4type = P4_NOTUSED;
   }else if( n==P4_KEYINFO ){
-    KeyInfo *pKeyInfo;
-    int nField, nByte;
+    KeyInfo *pOrig, *pNew;
 
-    nField = ((KeyInfo*)zP4)->nField;
-    nByte = sizeof(*pKeyInfo) + (nField-1)*sizeof(pKeyInfo->aColl[0]) + nField;
-    pKeyInfo = sqlite3DbMallocRaw(0, nByte);
-    pOp->p4.pKeyInfo = pKeyInfo;
-    if( pKeyInfo ){
-      u8 *aSortOrder;
-      memcpy((char*)pKeyInfo, zP4, nByte - nField);
-      aSortOrder = pKeyInfo->aSortOrder;
-      if( aSortOrder ){
-        pKeyInfo->aSortOrder = (unsigned char*)&pKeyInfo->aColl[nField];
-        memcpy(pKeyInfo->aSortOrder, aSortOrder, nField);
-      }
+    pOrig = (KeyInfo*)zP4;
+    pOp->p4.pKeyInfo = pNew = sqlite3KeyInfoAlloc(db, pOrig->nField);
+    if( pNew ){
+      memcpy(pNew->aColl, pOrig->aColl, pOrig->nField*sizeof(pNew->aColl[0]));
+      memcpy(pNew->aSortOrder, pOrig->aSortOrder, pOrig->nField);
       pOp->p4type = P4_KEYINFO;
     }else{
       p->db->mallocFailed = 1;
@@ -61168,7 +60777,7 @@ SQLITE_PRIVATE void sqlite3VdbeChangeP4(Vdbe *p, int addr, const char *zP4, int
 
 #ifndef NDEBUG
 /*
-** Change the comment on the the most recently coded instruction.  Or
+** Change the comment on the most recently coded instruction.  Or
 ** insert a No-op and add the comment to that new instruction.  This
 ** makes the code easier to read during debugging.  None of this happens
 ** in a production build.
@@ -61255,26 +60864,23 @@ static char *displayP4(Op *pOp, char *zTemp, int nTemp){
     case P4_KEYINFO: {
       int i, j;
       KeyInfo *pKeyInfo = pOp->p4.pKeyInfo;
+      assert( pKeyInfo->aSortOrder!=0 );
       sqlite3_snprintf(nTemp, zTemp, "keyinfo(%d", pKeyInfo->nField);
       i = sqlite3Strlen30(zTemp);
       for(j=0; j<pKeyInfo->nField; j++){
         CollSeq *pColl = pKeyInfo->aColl[j];
-        if( pColl ){
-          int n = sqlite3Strlen30(pColl->zName);
-          if( i+n>nTemp-6 ){
-            memcpy(&zTemp[i],",...",4);
-            break;
-          }
-          zTemp[i++] = ',';
-          if( pKeyInfo->aSortOrder && pKeyInfo->aSortOrder[j] ){
-            zTemp[i++] = '-';
-          }
-          memcpy(&zTemp[i], pColl->zName,n+1);
-          i += n;
-        }else if( i+4<nTemp-6 ){
-          memcpy(&zTemp[i],",nil",4);
-          i += 4;
+        const char *zColl = pColl ? pColl->zName : "nil";
+        int n = sqlite3Strlen30(zColl);
+        if( i+n>nTemp-6 ){
+          memcpy(&zTemp[i],",...",4);
+          break;
         }
+        zTemp[i++] = ',';
+        if( pKeyInfo->aSortOrder[j] ){
+          zTemp[i++] = '-';
+        }
+        memcpy(&zTemp[i], zColl, n+1);
+        i += n;
       }
       zTemp[i++] = ')';
       zTemp[i] = 0;
@@ -61935,7 +61541,7 @@ SQLITE_PRIVATE void sqlite3VdbeMakeReady(
     zEnd = &zCsr[nByte];
   }while( nByte && !db->mallocFailed );
 
-  p->nCursor = (u16)nCursor;
+  p->nCursor = nCursor;
   p->nOnceFlag = nOnce;
   if( p->aVar ){
     p->nVar = (ynVar)nVar;
@@ -62043,6 +61649,10 @@ static void closeAllCursors(Vdbe *p){
     p->pDelFrame = pDel->pParent;
     sqlite3VdbeFrameDelete(pDel);
   }
+
+  /* Delete any auxdata allocations made by the VM */
+  sqlite3VdbeDeleteAuxData(p, -1, 0);
+  assert( p->pAuxData==0 );
 }
 
 /*
@@ -62151,7 +61761,7 @@ static int vdbeCommit(sqlite3 *db, Vdbe *p){
   ** required, as an xSync() callback may add an attached database
   ** to the transaction.
   */
-  rc = sqlite3VtabSync(db, &p->zErrMsg);
+  rc = sqlite3VtabSync(db, p);
 
   /* This loop determines (a) if the commit hook should be invoked and
   ** (b) how many database files have open write transactions, not 
@@ -62164,7 +61774,9 @@ static int vdbeCommit(sqlite3 *db, Vdbe *p){
     if( sqlite3BtreeIsInTrans(pBt) ){
       needXcommit = 1;
       if( i!=1 ) nTrans++;
+      sqlite3BtreeEnter(pBt);
       rc = sqlite3PagerExclusiveLock(sqlite3BtreePager(pBt));
+      sqlite3BtreeLeave(pBt);
     }
   }
   if( rc!=SQLITE_OK ){
@@ -62175,7 +61787,7 @@ static int vdbeCommit(sqlite3 *db, Vdbe *p){
   if( needXcommit && db->xCommitCallback ){
     rc = db->xCommitCallback(db->pCommitArg);
     if( rc ){
-      return SQLITE_CONSTRAINT;
+      return SQLITE_CONSTRAINT_COMMITHOOK;
     }
   }
 
@@ -62368,7 +61980,7 @@ static int vdbeCommit(sqlite3 *db, Vdbe *p){
 }
 
 /* 
-** This routine checks that the sqlite3.activeVdbeCnt count variable
+** This routine checks that the sqlite3.nVdbeActive count variable
 ** matches the number of vdbe's in the list sqlite3.pVdbe that are
 ** currently active. An assertion fails if the two counts do not match.
 ** This is an internal self-check only - it is not an essential processing
@@ -62381,16 +61993,19 @@ static void checkActiveVdbeCnt(sqlite3 *db){
   Vdbe *p;
   int cnt = 0;
   int nWrite = 0;
+  int nRead = 0;
   p = db->pVdbe;
   while( p ){
     if( p->magic==VDBE_MAGIC_RUN && p->pc>=0 ){
       cnt++;
       if( p->readOnly==0 ) nWrite++;
+      if( p->bIsReader ) nRead++;
     }
     p = p->pNext;
   }
-  assert( cnt==db->activeVdbeCnt );
-  assert( nWrite==db->writeVdbeCnt );
+  assert( cnt==db->nVdbeActive );
+  assert( nWrite==db->nVdbeWrite );
+  assert( nRead==db->nVdbeRead );
 }
 #else
 #define checkActiveVdbeCnt(x)
@@ -62401,7 +62016,7 @@ static void checkActiveVdbeCnt(sqlite3 *db){
 ** close it now. Argument eOp must be either SAVEPOINT_ROLLBACK or
 ** SAVEPOINT_RELEASE. If it is SAVEPOINT_ROLLBACK, then the statement
 ** transaction is rolled back. If eOp is SAVEPOINT_RELEASE, then the 
-** statement transaction is commtted.
+** statement transaction is committed.
 **
 ** If an IO error occurs, an SQLITE_IOERR_XXX error code is returned. 
 ** Otherwise SQLITE_OK.
@@ -62412,7 +62027,7 @@ SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
 
   /* If p->iStatement is greater than zero, then this Vdbe opened a 
   ** statement transaction that should be closed here. The only exception
-  ** is that an IO error may have occured, causing an emergency rollback.
+  ** is that an IO error may have occurred, causing an emergency rollback.
   ** In this case (db->nStatement==0), and there is nothing to do.
   */
   if( db->nStatement && p->iStatement ){
@@ -62455,6 +62070,7 @@ SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
     ** the statement transaction was opened.  */
     if( eOp==SAVEPOINT_ROLLBACK ){
       db->nDeferredCons = p->nStmtDefCons;
+      db->nDeferredImmCons = p->nStmtDefImmCons;
     }
   }
   return rc;
@@ -62467,14 +62083,16 @@ SQLITE_PRIVATE int sqlite3VdbeCloseStatement(Vdbe *p, int eOp){
 ** violations, return SQLITE_ERROR. Otherwise, SQLITE_OK.
 **
 ** If there are outstanding FK violations and this function returns 
-** SQLITE_ERROR, set the result of the VM to SQLITE_CONSTRAINT and write
-** an error message to it. Then return SQLITE_ERROR.
+** SQLITE_ERROR, set the result of the VM to SQLITE_CONSTRAINT_FOREIGNKEY
+** and write an error message to it. Then return SQLITE_ERROR.
 */
 #ifndef SQLITE_OMIT_FOREIGN_KEY
 SQLITE_PRIVATE int sqlite3VdbeCheckFk(Vdbe *p, int deferred){
   sqlite3 *db = p->db;
-  if( (deferred && db->nDeferredCons>0) || (!deferred && p->nFkConstraint>0) ){
-    p->rc = SQLITE_CONSTRAINT;
+  if( (deferred && (db->nDeferredCons+db->nDeferredImmCons)>0) 
+   || (!deferred && p->nFkConstraint>0) 
+  ){
+    p->rc = SQLITE_CONSTRAINT_FOREIGNKEY;
     p->errorAction = OE_Abort;
     sqlite3SetString(&p->zErrMsg, db, "foreign key constraint failed");
     return SQLITE_ERROR;
@@ -62526,8 +62144,9 @@ SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
   }
   checkActiveVdbeCnt(db);
 
-  /* No commit or rollback needed if the program never started */
-  if( p->pc>=0 ){
+  /* No commit or rollback needed if the program never started or if the
+  ** SQL statement does not read or write a database file.  */
+  if( p->pc>=0 && p->bIsReader ){
     int mrc;   /* Primary error code from p->rc */
     int eStatementOp = 0;
     int isSpecialError;            /* Set to true if a 'special' error */
@@ -62548,7 +62167,7 @@ SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
       **
       ** Even if the statement is read-only, it is important to perform
       ** a statement or transaction rollback operation. If the error 
-      ** occured while writing to the journal, sub-journal or database
+      ** occurred while writing to the journal, sub-journal or database
       ** file as part of an effort to free up cache space (see function
       ** pagerStress() in pager.c), the rollback is required to restore 
       ** the pager to a consistent state.
@@ -62580,7 +62199,7 @@ SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
     */
     if( !sqlite3VtabInSync(db) 
      && db->autoCommit 
-     && db->writeVdbeCnt==(p->readOnly==0) 
+     && db->nVdbeWrite==(p->readOnly==0) 
     ){
       if( p->rc==SQLITE_OK || (p->errorAction==OE_Fail && !isSpecialError) ){
         rc = sqlite3VdbeCheckFk(p, 1);
@@ -62589,7 +62208,7 @@ SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
             sqlite3VdbeLeave(p);
             return SQLITE_ERROR;
           }
-          rc = SQLITE_CONSTRAINT;
+          rc = SQLITE_CONSTRAINT_FOREIGNKEY;
         }else{ 
           /* The auto-commit flag is true, the vdbe program was successful 
           ** or hit an 'OR FAIL' constraint and there are no deferred foreign
@@ -62605,6 +62224,8 @@ SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
           sqlite3RollbackAll(db, SQLITE_OK);
         }else{
           db->nDeferredCons = 0;
+          db->nDeferredImmCons = 0;
+          db->flags &= ~SQLITE_DeferFKs;
           sqlite3CommitInternalChanges(db);
         }
       }else{
@@ -62632,7 +62253,7 @@ SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
     if( eStatementOp ){
       rc = sqlite3VdbeCloseStatement(p, eStatementOp);
       if( rc ){
-        if( p->rc==SQLITE_OK || p->rc==SQLITE_CONSTRAINT ){
+        if( p->rc==SQLITE_OK || (p->rc&0xff)==SQLITE_CONSTRAINT ){
           p->rc = rc;
           sqlite3DbFree(db, p->zErrMsg);
           p->zErrMsg = 0;
@@ -62661,11 +62282,12 @@ SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
 
   /* We have successfully halted and closed the VM.  Record this fact. */
   if( p->pc>=0 ){
-    db->activeVdbeCnt--;
-    if( !p->readOnly ){
-      db->writeVdbeCnt--;
-    }
-    assert( db->activeVdbeCnt>=db->writeVdbeCnt );
+    db->nVdbeActive--;
+    if( !p->readOnly ) db->nVdbeWrite--;
+    if( p->bIsReader ) db->nVdbeRead--;
+    assert( db->nVdbeActive>=db->nVdbeRead );
+    assert( db->nVdbeRead>=db->nVdbeWrite );
+    assert( db->nVdbeWrite>=0 );
   }
   p->magic = VDBE_MAGIC_HALT;
   checkActiveVdbeCnt(db);
@@ -62681,7 +62303,7 @@ SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
     sqlite3ConnectionUnlocked(db);
   }
 
-  assert( db->activeVdbeCnt>0 || db->autoCommit==0 || db->nStatement==0 );
+  assert( db->nVdbeActive>0 || db->autoCommit==0 || db->nStatement==0 );
   return (p->rc==SQLITE_BUSY ? SQLITE_BUSY : SQLITE_OK);
 }
 
@@ -62718,6 +62340,27 @@ SQLITE_PRIVATE int sqlite3VdbeTransferError(Vdbe *p){
   return rc;
 }
 
+#ifdef SQLITE_ENABLE_SQLLOG
+/*
+** If an SQLITE_CONFIG_SQLLOG hook is registered and the VM has been run, 
+** invoke it.
+*/
+static void vdbeInvokeSqllog(Vdbe *v){
+  if( sqlite3GlobalConfig.xSqllog && v->rc==SQLITE_OK && v->zSql && v->pc>=0 ){
+    char *zExpanded = sqlite3VdbeExpandSql(v, v->zSql);
+    assert( v->db->init.busy==0 );
+    if( zExpanded ){
+      sqlite3GlobalConfig.xSqllog(
+          sqlite3GlobalConfig.pSqllogArg, v->db, zExpanded, 1
+      );
+      sqlite3DbFree(v->db, zExpanded);
+    }
+  }
+}
+#else
+# define vdbeInvokeSqllog(x)
+#endif
+
 /*
 ** Clean up a VDBE after execution but do not delete the VDBE just yet.
 ** Write any error messages into *pzErrMsg.  Return the result code.
@@ -62745,6 +62388,7 @@ SQLITE_PRIVATE int sqlite3VdbeReset(Vdbe *p){
   ** instructions yet, leave the main database error information unchanged.
   */
   if( p->pc>=0 ){
+    vdbeInvokeSqllog(p);
     sqlite3VdbeTransferError(p);
     sqlite3DbFree(db, p->zErrMsg);
     p->zErrMsg = 0;
@@ -62807,31 +62451,48 @@ SQLITE_PRIVATE int sqlite3VdbeFinalize(Vdbe *p){
 }
 
 /*
-** Call the destructor for each auxdata entry in pVdbeFunc for which
-** the corresponding bit in mask is clear.  Auxdata entries beyond 31
-** are always destroyed.  To destroy all auxdata entries, call this
-** routine with mask==0.
+** If parameter iOp is less than zero, then invoke the destructor for
+** all auxiliary data pointers currently cached by the VM passed as
+** the first argument.
+**
+** Or, if iOp is greater than or equal to zero, then the destructor is
+** only invoked for those auxiliary data pointers created by the user 
+** function invoked by the OP_Function opcode at instruction iOp of 
+** VM pVdbe, and only then if:
+**
+**    * the associated function parameter is the 32nd or later (counting
+**      from left to right), or
+**
+**    * the corresponding bit in argument mask is clear (where the first
+**      function parameter corrsponds to bit 0 etc.).
 */
-SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc *pVdbeFunc, int mask){
-  int i;
-  for(i=0; i<pVdbeFunc->nAux; i++){
-    struct AuxData *pAux = &pVdbeFunc->apAux[i];
-    if( (i>31 || !(mask&(((u32)1)<<i))) && pAux->pAux ){
+SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(Vdbe *pVdbe, int iOp, int mask){
+  AuxData **pp = &pVdbe->pAuxData;
+  while( *pp ){
+    AuxData *pAux = *pp;
+    if( (iOp<0)
+     || (pAux->iOp==iOp && (pAux->iArg>31 || !(mask & ((u32)1<<pAux->iArg))))
+    ){
       if( pAux->xDelete ){
         pAux->xDelete(pAux->pAux);
       }
-      pAux->pAux = 0;
+      *pp = pAux->pNext;
+      sqlite3DbFree(pVdbe->db, pAux);
+    }else{
+      pp= &pAux->pNext;
     }
   }
 }
 
 /*
-** Free all memory associated with the Vdbe passed as the second argument.
+** Free all memory associated with the Vdbe passed as the second argument,
+** except for object itself, which is preserved.
+**
 ** The difference between this function and sqlite3VdbeDelete() is that
 ** VdbeDelete() also unlinks the Vdbe from the list of VMs associated with
-** the database connection.
+** the database connection and frees the object itself.
 */
-SQLITE_PRIVATE void sqlite3VdbeDeleteObject(sqlite3 *db, Vdbe *p){
+SQLITE_PRIVATE void sqlite3VdbeClearObject(sqlite3 *db, Vdbe *p){
   SubProgram *pSub, *pNext;
   int i;
   assert( p->db==0 || p->db==db );
@@ -62852,7 +62513,6 @@ SQLITE_PRIVATE void sqlite3VdbeDeleteObject(sqlite3 *db, Vdbe *p){
   sqlite3DbFree(db, p->zExplain);
   sqlite3DbFree(db, p->pExplain);
 #endif
-  sqlite3DbFree(db, p);
 }
 
 /*
@@ -62863,6 +62523,8 @@ SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe *p){
 
   if( NEVER(p==0) ) return;
   db = p->db;
+  assert( sqlite3_mutex_held(db->mutex) );
+  sqlite3VdbeClearObject(db, p);
   if( p->pPrev ){
     p->pPrev->pNext = p->pNext;
   }else{
@@ -62874,7 +62536,7 @@ SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe *p){
   }
   p->magic = VDBE_MAGIC_DEAD;
   p->db = 0;
-  sqlite3VdbeDeleteObject(db, p);
+  sqlite3DbFree(db, p);
 }
 
 /*
@@ -62937,7 +62599,7 @@ SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(VdbeCursor *p){
 ** the blob of data that it corresponds to. In a table record, all serial
 ** types are stored at the start of the record, and the blobs of data at
 ** the end. Hence these functions allow the caller to handle the
-** serial-type and data blob seperately.
+** serial-type and data blob separately.
 **
 ** The following table describes the various storage classes for data:
 **
@@ -62976,9 +62638,6 @@ SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem *pMem, int file_format){
 #   define MAX_6BYTE ((((i64)0x00008000)<<32)-1)
     i64 i = pMem->u.i;
     u64 u;
-    if( file_format>=4 && (i&1)==i ){
-      return 8+(u32)i;
-    }
     if( i<0 ){
       if( i<(-MAX_6BYTE) ) return 6;
       /* Previous test prevents:  u = -(-9223372036854775808) */
@@ -62986,7 +62645,9 @@ SQLITE_PRIVATE u32 sqlite3VdbeSerialType(Mem *pMem, int file_format){
     }else{
       u = i;
     }
-    if( u<=127 ) return 1;
+    if( u<=127 ){
+      return ((i&1)==i && file_format>=4) ? 8+(u32)u : 1;
+    }
     if( u<=32767 ) return 2;
     if( u<=8388607 ) return 3;
     if( u<=2147483647 ) return 4;
@@ -63271,6 +62932,7 @@ SQLITE_PRIVATE UnpackedRecord *sqlite3VdbeAllocUnpackedRecord(
   }
 
   p->aMem = (Mem*)&((char*)p)[ROUND8(sizeof(UnpackedRecord))];
+  assert( pKeyInfo->aSortOrder!=0 );
   p->pKeyInfo = pKeyInfo;
   p->nField = pKeyInfo->nField + 1;
   return p;
@@ -63336,11 +62998,10 @@ SQLITE_PRIVATE int sqlite3VdbeRecordCompare(
   int nKey1, const void *pKey1, /* Left key */
   UnpackedRecord *pPKey2        /* Right key */
 ){
-  int d1;            /* Offset into aKey[] of next data element */
+  u32 d1;            /* Offset into aKey[] of next data element */
   u32 idx1;          /* Offset into aKey[] of next header element */
   u32 szHdr1;        /* Number of bytes in header */
   int i = 0;
-  int nField;
   int rc = 0;
   const unsigned char *aKey1 = (const unsigned char *)pKey1;
   KeyInfo *pKeyInfo;
@@ -63363,13 +63024,25 @@ SQLITE_PRIVATE int sqlite3VdbeRecordCompare(
   
   idx1 = getVarint32(aKey1, szHdr1);
   d1 = szHdr1;
-  nField = pKeyInfo->nField;
+  assert( pKeyInfo->nField+1>=pPKey2->nField );
+  assert( pKeyInfo->aSortOrder!=0 );
   while( idx1<szHdr1 && i<pPKey2->nField ){
     u32 serial_type1;
 
     /* Read the serial types for the next element in each key. */
     idx1 += getVarint32( aKey1+idx1, serial_type1 );
-    if( d1>=nKey1 && sqlite3VdbeSerialTypeLen(serial_type1)>0 ) break;
+
+    /* Verify that there is enough key space remaining to avoid
+    ** a buffer overread.  The "d1+serial_type1+2" subexpression will
+    ** always be greater than or equal to the amount of required key space.
+    ** Use that approximation to avoid the more expensive call to
+    ** sqlite3VdbeSerialTypeLen() in the common case.
+    */
+    if( d1+serial_type1+2>(u32)nKey1
+     && d1+sqlite3VdbeSerialTypeLen(serial_type1)>(u32)nKey1 
+    ){
+      break;
+    }
 
     /* Extract the values to be compared.
     */
@@ -63377,13 +63050,12 @@ SQLITE_PRIVATE int sqlite3VdbeRecordCompare(
 
     /* Do the comparison
     */
-    rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i],
-                           i<nField ? pKeyInfo->aColl[i] : 0);
+    rc = sqlite3MemCompare(&mem1, &pPKey2->aMem[i], pKeyInfo->aColl[i]);
     if( rc!=0 ){
       assert( mem1.zMalloc==0 );  /* See comment below */
 
       /* Invert the result if we are using DESC sort order. */
-      if( pKeyInfo->aSortOrder && i<nField && pKeyInfo->aSortOrder[i] ){
+      if( pKeyInfo->aSortOrder[i] ){
         rc = -rc;
       }
     
@@ -63598,7 +63270,7 @@ SQLITE_PRIVATE sqlite3 *sqlite3VdbeDb(Vdbe *v){
 **
 ** The returned value must be freed by the caller using sqlite3ValueFree().
 */
-SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetValue(Vdbe *v, int iVar, u8 aff){
+SQLITE_PRIVATE sqlite3_value *sqlite3VdbeGetBoundValue(Vdbe *v, int iVar, u8 aff){
   assert( iVar>0 );
   if( v ){
     Mem *pMem = &v->aVar[iVar-1];
@@ -63629,6 +63301,21 @@ SQLITE_PRIVATE void sqlite3VdbeSetVarmask(Vdbe *v, int iVar){
   }
 }
 
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/*
+** Transfer error message text from an sqlite3_vtab.zErrMsg (text stored
+** in memory obtained from sqlite3_malloc) into a Vdbe.zErrMsg (text stored
+** in memory obtained from sqlite3DbMalloc).
+*/
+SQLITE_PRIVATE void sqlite3VtabImportErrmsg(Vdbe *p, sqlite3_vtab *pVtab){
+  sqlite3 *db = p->db;
+  sqlite3DbFree(db, p->zErrMsg);
+  p->zErrMsg = sqlite3DbStrDup(db, pVtab->zErrMsg);
+  sqlite3_free(pVtab->zErrMsg);
+  pVtab->zErrMsg = 0;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+
 /************** End of vdbeaux.c *********************************************/
 /************** Begin file vdbeapi.c *****************************************/
 /*
@@ -63702,17 +63389,11 @@ SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt){
   }else{
     Vdbe *v = (Vdbe*)pStmt;
     sqlite3 *db = v->db;
-#if SQLITE_THREADSAFE
-    sqlite3_mutex *mutex;
-#endif
     if( vdbeSafety(v) ) return SQLITE_MISUSE_BKPT;
-#if SQLITE_THREADSAFE
-    mutex = v->db->mutex;
-#endif
-    sqlite3_mutex_enter(mutex);
+    sqlite3_mutex_enter(db->mutex);
     rc = sqlite3VdbeFinalize(v);
     rc = sqlite3ApiExit(db, rc);
-    sqlite3_mutex_leave(mutex);
+    sqlite3LeaveMutexAndCloseZombie(db);
   }
   return rc;
 }
@@ -63848,12 +63529,14 @@ SQLITE_API void sqlite3_result_double(sqlite3_context *pCtx, double rVal){
 SQLITE_API void sqlite3_result_error(sqlite3_context *pCtx, const char *z, int n){
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
   pCtx->isError = SQLITE_ERROR;
+  pCtx->fErrorOrAux = 1;
   sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF8, SQLITE_TRANSIENT);
 }
 #ifndef SQLITE_OMIT_UTF16
 SQLITE_API void sqlite3_result_error16(sqlite3_context *pCtx, const void *z, int n){
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
   pCtx->isError = SQLITE_ERROR;
+  pCtx->fErrorOrAux = 1;
   sqlite3VdbeMemSetStr(&pCtx->s, z, n, SQLITE_UTF16NATIVE, SQLITE_TRANSIENT);
 }
 #endif
@@ -63917,6 +63600,7 @@ SQLITE_API void sqlite3_result_zeroblob(sqlite3_context *pCtx, int n){
 }
 SQLITE_API void sqlite3_result_error_code(sqlite3_context *pCtx, int errCode){
   pCtx->isError = errCode;
+  pCtx->fErrorOrAux = 1;
   if( pCtx->s.flags & MEM_Null ){
     sqlite3VdbeMemSetStr(&pCtx->s, sqlite3ErrStr(errCode), -1, 
                          SQLITE_UTF8, SQLITE_STATIC);
@@ -63927,6 +63611,7 @@ SQLITE_API void sqlite3_result_error_code(sqlite3_context *pCtx, int errCode){
 SQLITE_API void sqlite3_result_error_toobig(sqlite3_context *pCtx){
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
   pCtx->isError = SQLITE_TOOBIG;
+  pCtx->fErrorOrAux = 1;
   sqlite3VdbeMemSetStr(&pCtx->s, "string or blob too big", -1, 
                        SQLITE_UTF8, SQLITE_STATIC);
 }
@@ -63936,6 +63621,7 @@ SQLITE_API void sqlite3_result_error_nomem(sqlite3_context *pCtx){
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
   sqlite3VdbeMemSetNull(&pCtx->s);
   pCtx->isError = SQLITE_NOMEM;
+  pCtx->fErrorOrAux = 1;
   pCtx->s.db->mallocFailed = 1;
 }
 
@@ -64019,11 +63705,13 @@ static int sqlite3Step(Vdbe *p){
     ** reset the interrupt flag.  This prevents a call to sqlite3_interrupt
     ** from interrupting a statement that has not yet started.
     */
-    if( db->activeVdbeCnt==0 ){
+    if( db->nVdbeActive==0 ){
       db->u1.isInterrupted = 0;
     }
 
-    assert( db->writeVdbeCnt>0 || db->autoCommit==0 || db->nDeferredCons==0 );
+    assert( db->nVdbeWrite>0 || db->autoCommit==0 
+        || (db->nDeferredCons==0 && db->nDeferredImmCons==0)
+    );
 
 #ifndef SQLITE_OMIT_TRACE
     if( db->xProfile && !db->init.busy ){
@@ -64031,8 +63719,9 @@ static int sqlite3Step(Vdbe *p){
     }
 #endif
 
-    db->activeVdbeCnt++;
-    if( p->readOnly==0 ) db->writeVdbeCnt++;
+    db->nVdbeActive++;
+    if( p->readOnly==0 ) db->nVdbeWrite++;
+    if( p->bIsReader ) db->nVdbeRead++;
     p->pc = 0;
   }
 #ifndef SQLITE_OMIT_EXPLAIN
@@ -64041,9 +63730,9 @@ static int sqlite3Step(Vdbe *p){
   }else
 #endif /* SQLITE_OMIT_EXPLAIN */
   {
-    db->vdbeExecCnt++;
+    db->nVdbeExec++;
     rc = sqlite3VdbeExec(p);
-    db->vdbeExecCnt--;
+    db->nVdbeExec--;
   }
 
 #ifndef SQLITE_OMIT_TRACE
@@ -64082,7 +63771,7 @@ end_of_step:
   assert( p->rc!=SQLITE_ROW && p->rc!=SQLITE_DONE );
   if( p->isPrepareV2 && rc!=SQLITE_ROW && rc!=SQLITE_DONE ){
     /* If this statement was prepared using sqlite3_prepare_v2(), and an
-    ** error has occured, then return the error code in p->rc to the
+    ** error has occurred, then return the error code in p->rc to the
     ** caller. Set the error code in the database handle to the same value.
     */ 
     rc = sqlite3VdbeTransferError(p);
@@ -64090,14 +63779,6 @@ end_of_step:
   return (rc&db->errMask);
 }
 
-/*
-** The maximum number of times that a statement will try to reparse
-** itself before giving up and returning SQLITE_SCHEMA.
-*/
-#ifndef SQLITE_MAX_SCHEMA_RETRY
-# define SQLITE_MAX_SCHEMA_RETRY 5
-#endif
-
 /*
 ** This is the top-level implementation of sqlite3_step().  Call
 ** sqlite3Step() to do most of the work.  If a schema error occurs,
@@ -64115,10 +63796,12 @@ SQLITE_API int sqlite3_step(sqlite3_stmt *pStmt){
   }
   db = v->db;
   sqlite3_mutex_enter(db->mutex);
+  v->doingRerun = 0;
   while( (rc = sqlite3Step(v))==SQLITE_SCHEMA
          && cnt++ < SQLITE_MAX_SCHEMA_RETRY
          && (rc2 = rc = sqlite3Reprepare(v))==SQLITE_OK ){
     sqlite3_reset(pStmt);
+    v->doingRerun = 1;
     assert( v->expired==0 );
   }
   if( rc2!=SQLITE_OK && ALWAYS(v->isPrepareV2) && ALWAYS(db->pErr) ){
@@ -64224,14 +63907,14 @@ SQLITE_API void *sqlite3_aggregate_context(sqlite3_context *p, int nByte){
 ** the user-function defined by pCtx.
 */
 SQLITE_API void *sqlite3_get_auxdata(sqlite3_context *pCtx, int iArg){
-  VdbeFunc *pVdbeFunc;
+  AuxData *pAuxData;
 
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pVdbeFunc = pCtx->pVdbeFunc;
-  if( !pVdbeFunc || iArg>=pVdbeFunc->nAux || iArg<0 ){
-    return 0;
+  for(pAuxData=pCtx->pVdbe->pAuxData; pAuxData; pAuxData=pAuxData->pNext){
+    if( pAuxData->iOp==pCtx->iOp && pAuxData->iArg==iArg ) break;
   }
-  return pVdbeFunc->apAux[iArg].pAux;
+
+  return (pAuxData ? pAuxData->pAux : 0);
 }
 
 /*
@@ -64245,29 +63928,30 @@ SQLITE_API void sqlite3_set_auxdata(
   void *pAux, 
   void (*xDelete)(void*)
 ){
-  struct AuxData *pAuxData;
-  VdbeFunc *pVdbeFunc;
-  if( iArg<0 ) goto failed;
+  AuxData *pAuxData;
+  Vdbe *pVdbe = pCtx->pVdbe;
 
   assert( sqlite3_mutex_held(pCtx->s.db->mutex) );
-  pVdbeFunc = pCtx->pVdbeFunc;
-  if( !pVdbeFunc || pVdbeFunc->nAux<=iArg ){
-    int nAux = (pVdbeFunc ? pVdbeFunc->nAux : 0);
-    int nMalloc = sizeof(VdbeFunc) + sizeof(struct AuxData)*iArg;
-    pVdbeFunc = sqlite3DbRealloc(pCtx->s.db, pVdbeFunc, nMalloc);
-    if( !pVdbeFunc ){
-      goto failed;
-    }
-    pCtx->pVdbeFunc = pVdbeFunc;
-    memset(&pVdbeFunc->apAux[nAux], 0, sizeof(struct AuxData)*(iArg+1-nAux));
-    pVdbeFunc->nAux = iArg+1;
-    pVdbeFunc->pFunc = pCtx->pFunc;
-  }
+  if( iArg<0 ) goto failed;
 
-  pAuxData = &pVdbeFunc->apAux[iArg];
-  if( pAuxData->pAux && pAuxData->xDelete ){
+  for(pAuxData=pVdbe->pAuxData; pAuxData; pAuxData=pAuxData->pNext){
+    if( pAuxData->iOp==pCtx->iOp && pAuxData->iArg==iArg ) break;
+  }
+  if( pAuxData==0 ){
+    pAuxData = sqlite3DbMallocZero(pVdbe->db, sizeof(AuxData));
+    if( !pAuxData ) goto failed;
+    pAuxData->iOp = pCtx->iOp;
+    pAuxData->iArg = iArg;
+    pAuxData->pNext = pVdbe->pAuxData;
+    pVdbe->pAuxData = pAuxData;
+    if( pCtx->fErrorOrAux==0 ){
+      pCtx->isError = 0;
+      pCtx->fErrorOrAux = 1;
+    }
+  }else if( pAuxData->xDelete ){
     pAuxData->xDelete(pAuxData->pAux);
   }
+
   pAuxData->pAux = pAux;
   pAuxData->xDelete = xDelete;
   return;
@@ -64456,13 +64140,6 @@ SQLITE_API int sqlite3_column_type(sqlite3_stmt *pStmt, int i){
   return iType;
 }
 
-/* The following function is experimental and subject to change or
-** removal */
-/*int sqlite3_column_numeric_type(sqlite3_stmt *pStmt, int i){
-**  return sqlite3_value_numeric_type( columnMem(pStmt,i) );
-**}
-*/
-
 /*
 ** Convert the N-th element of pStmt->pColName[] into a string using
 ** xFunc() then return that string.  If N is out of range, return 0.
@@ -64833,7 +64510,7 @@ SQLITE_PRIVATE int sqlite3VdbeParameterIndex(Vdbe *p, const char *zName, int nNa
   if( zName ){
     for(i=0; i<p->nzVar; i++){
       const char *z = p->azVar[i];
-      if( z && memcmp(z,zName,nName)==0 && z[nName]==0 ){
+      if( z && strncmp(z,zName,nName)==0 && z[nName]==0 ){
         return i+1;
       }
     }
@@ -64939,9 +64616,9 @@ SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt){
 */
 SQLITE_API int sqlite3_stmt_status(sqlite3_stmt *pStmt, int op, int resetFlag){
   Vdbe *pVdbe = (Vdbe*)pStmt;
-  int v = pVdbe->aCounter[op-1];
-  if( resetFlag ) pVdbe->aCounter[op-1] = 0;
-  return v;
+  u32 v = pVdbe->aCounter[op];
+  if( resetFlag ) pVdbe->aCounter[op] = 0;
+  return (int)v;
 }
 
 /************** End of vdbeapi.c *********************************************/
@@ -64993,12 +64670,17 @@ static int findNextHostParameter(const char *zSql, int *pnToken){
 
 /*
 ** This function returns a pointer to a nul-terminated string in memory
-** obtained from sqlite3DbMalloc(). If sqlite3.vdbeExecCnt is 1, then the
+** obtained from sqlite3DbMalloc(). If sqlite3.nVdbeExec is 1, then the
 ** string contains a copy of zRawSql but with host parameters expanded to 
-** their current bindings. Or, if sqlite3.vdbeExecCnt is greater than 1, 
+** their current bindings. Or, if sqlite3.nVdbeExec is greater than 1, 
 ** then the returned string holds a copy of zRawSql with "-- " prepended
 ** to each line of text.
 **
+** If the SQLITE_TRACE_SIZE_LIMIT macro is defined to an integer, then
+** then long strings and blobs are truncated to that many bytes.  This
+** can be used to prevent unreasonably large trace strings when dealing
+** with large (multi-megabyte) strings and blobs.
+**
 ** The calling function is responsible for making sure the memory returned
 ** is eventually freed.
 **
@@ -65028,7 +64710,7 @@ SQLITE_PRIVATE char *sqlite3VdbeExpandSql(
   sqlite3StrAccumInit(&out, zBase, sizeof(zBase), 
                       db->aLimit[SQLITE_LIMIT_LENGTH]);
   out.db = db;
-  if( db->vdbeExecCnt>1 ){
+  if( db->nVdbeExec>1 ){
     while( *zRawSql ){
       const char *zStart = zRawSql;
       while( *(zRawSql++)!='\n' && *zRawSql );
@@ -65069,30 +64751,49 @@ SQLITE_PRIVATE char *sqlite3VdbeExpandSql(
       }else if( pVar->flags & MEM_Real ){
         sqlite3XPrintf(&out, "%!.15g", pVar->r);
       }else if( pVar->flags & MEM_Str ){
+        int nOut;  /* Number of bytes of the string text to include in output */
 #ifndef SQLITE_OMIT_UTF16
         u8 enc = ENC(db);
+        Mem utf8;
         if( enc!=SQLITE_UTF8 ){
-          Mem utf8;
           memset(&utf8, 0, sizeof(utf8));
           utf8.db = db;
           sqlite3VdbeMemSetStr(&utf8, pVar->z, pVar->n, enc, SQLITE_STATIC);
           sqlite3VdbeChangeEncoding(&utf8, SQLITE_UTF8);
-          sqlite3XPrintf(&out, "'%.*q'", utf8.n, utf8.z);
-          sqlite3VdbeMemRelease(&utf8);
-        }else
-#endif
-        {
-          sqlite3XPrintf(&out, "'%.*q'", pVar->n, pVar->z);
+          pVar = &utf8;
         }
+#endif
+        nOut = pVar->n;
+#ifdef SQLITE_TRACE_SIZE_LIMIT
+        if( nOut>SQLITE_TRACE_SIZE_LIMIT ){
+          nOut = SQLITE_TRACE_SIZE_LIMIT;
+          while( nOut<pVar->n && (pVar->z[nOut]&0xc0)==0x80 ){ nOut++; }
+        }
+#endif    
+        sqlite3XPrintf(&out, "'%.*q'", nOut, pVar->z);
+#ifdef SQLITE_TRACE_SIZE_LIMIT
+        if( nOut<pVar->n ) sqlite3XPrintf(&out, "/*+%d bytes*/", pVar->n-nOut);
+#endif
+#ifndef SQLITE_OMIT_UTF16
+        if( enc!=SQLITE_UTF8 ) sqlite3VdbeMemRelease(&utf8);
+#endif
       }else if( pVar->flags & MEM_Zero ){
         sqlite3XPrintf(&out, "zeroblob(%d)", pVar->u.nZero);
       }else{
+        int nOut;  /* Number of bytes of the blob to include in output */
         assert( pVar->flags & MEM_Blob );
         sqlite3StrAccumAppend(&out, "x'", 2);
-        for(i=0; i<pVar->n; i++){
+        nOut = pVar->n;
+#ifdef SQLITE_TRACE_SIZE_LIMIT
+        if( nOut>SQLITE_TRACE_SIZE_LIMIT ) nOut = SQLITE_TRACE_SIZE_LIMIT;
+#endif
+        for(i=0; i<nOut; i++){
           sqlite3XPrintf(&out, "%02x", pVar->z[i]&0xff);
         }
         sqlite3StrAccumAppend(&out, "'", 1);
+#ifdef SQLITE_TRACE_SIZE_LIMIT
+        if( nOut<pVar->n ) sqlite3XPrintf(&out, "/*+%d bytes*/", pVar->n-nOut);
+#endif
       }
     }
   }
@@ -65115,9 +64816,8 @@ SQLITE_PRIVATE void sqlite3ExplainBegin(Vdbe *pVdbe){
   if( pVdbe ){
     Explain *p;
     sqlite3BeginBenignMalloc();
-    p = sqlite3_malloc( sizeof(Explain) );
+    p = (Explain *)sqlite3MallocZero( sizeof(Explain) );
     if( p ){
-      memset(p, 0, sizeof(*p));
       p->pVdbe = pVdbe;
       sqlite3_free(pVdbe->pExplain);
       pVdbe->pExplain = p;
@@ -65371,11 +65071,7 @@ SQLITE_API int sqlite3_found_count = 0;
        && sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}
 
 /* Return true if the cursor was opened using the OP_OpenSorter opcode. */
-#ifdef SQLITE_OMIT_MERGE_SORT
-# define isSorter(x) 0
-#else
 # define isSorter(x) ((x)->pSorter!=0)
-#endif
 
 /*
 ** Argument pMem points at a register that will be passed to a
@@ -65641,7 +65337,9 @@ SQLITE_PRIVATE void sqlite3VdbeMemPrettyPrint(Mem *pMem, char *zBuf){
 ** Print the value of a register for tracing purposes:
 */
 static void memTracePrint(FILE *out, Mem *p){
-  if( p->flags & MEM_Null ){
+  if( p->flags & MEM_Invalid ){
+    fprintf(out, " undefined");
+  }else if( p->flags & MEM_Null ){
     fprintf(out, " NULL");
   }else if( (p->flags & (MEM_Int|MEM_Str))==(MEM_Int|MEM_Str) ){
     fprintf(out, " si:%lld", p->u.i);
@@ -65807,19 +65505,6 @@ static int checkSavepointCount(sqlite3 *db){
 }
 #endif
 
-/*
-** Transfer error message text from an sqlite3_vtab.zErrMsg (text stored
-** in memory obtained from sqlite3_malloc) into a Vdbe.zErrMsg (text stored
-** in memory obtained from sqlite3DbMalloc).
-*/
-static void importVtabErrMsg(Vdbe *p, sqlite3_vtab *pVtab){
-  sqlite3 *db = p->db;
-  sqlite3DbFree(db, p->zErrMsg);
-  p->zErrMsg = sqlite3DbStrDup(db, pVtab->zErrMsg);
-  sqlite3_free(pVtab->zErrMsg);
-  pVtab->zErrMsg = 0;
-}
-
 
 /*
 ** Execute as much of a VDBE program as we can then return.
@@ -65862,16 +65547,16 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
   sqlite3 *db = p->db;       /* The database */
   u8 resetSchemaOnFault = 0; /* Reset schema after an error if positive */
   u8 encoding = ENC(db);     /* The database encoding */
+  int iCompare = 0;          /* Result of last OP_Compare operation */
+  unsigned nVmStep = 0;      /* Number of virtual machine steps */
 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-  int checkProgress;         /* True if progress callbacks are enabled */
-  int nProgressOps = 0;      /* Opcodes executed since progress callback. */
+  unsigned nProgressLimit = 0;/* Invoke xProgress() when nVmStep reaches this */
 #endif
   Mem *aMem = p->aMem;       /* Copy of p->aMem */
   Mem *pIn1 = 0;             /* 1st input operand */
   Mem *pIn2 = 0;             /* 2nd input operand */
   Mem *pIn3 = 0;             /* 3rd input operand */
   Mem *pOut = 0;             /* Output operand */
-  int iCompare = 0;          /* Result of last OP_Compare operation */
   int *aPermute = 0;         /* Permutation of columns for OP_Compare */
   i64 lastRowid = db->lastRowid;  /* Saved value of the last insert ROWID */
 #ifdef VDBE_PROFILE
@@ -65892,6 +65577,7 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
     } aa;
     struct OP_Null_stack_vars {
       int cnt;
+      u16 nullFlag;
     } ab;
     struct OP_Variable_stack_vars {
       Mem *pVar;       /* Value being transferred */
@@ -65902,39 +65588,43 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       int p1;          /* Register to copy from */
       int p2;          /* Register to copy to */
     } ad;
+    struct OP_Copy_stack_vars {
+      int n;
+    } ae;
     struct OP_ResultRow_stack_vars {
       Mem *pMem;
       int i;
-    } ae;
+    } af;
     struct OP_Concat_stack_vars {
       i64 nByte;
-    } af;
+    } ag;
     struct OP_Remainder_stack_vars {
+      char bIntint;   /* Started out as two integer operands */
       int flags;      /* Combined MEM_* flags from both inputs */
       i64 iA;         /* Integer value of left operand */
       i64 iB;         /* Integer value of right operand */
       double rA;      /* Real value of left operand */
       double rB;      /* Real value of right operand */
-    } ag;
+    } ah;
     struct OP_Function_stack_vars {
       int i;
       Mem *pArg;
       sqlite3_context ctx;
       sqlite3_value **apVal;
       int n;
-    } ah;
+    } ai;
     struct OP_ShiftRight_stack_vars {
       i64 iA;
       u64 uA;
       i64 iB;
       u8 op;
-    } ai;
+    } aj;
     struct OP_Ge_stack_vars {
       int res;            /* Result of the comparison of pIn1 against pIn3 */
       char affinity;      /* Affinity to use for comparison */
       u16 flags1;         /* Copy of initial value of pIn1->flags */
       u16 flags3;         /* Copy of initial value of pIn3->flags */
-    } aj;
+    } ak;
     struct OP_Compare_stack_vars {
       int n;
       int i;
@@ -65944,14 +65634,14 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       int idx;
       CollSeq *pColl;    /* Collating sequence to use on this term */
       int bRev;          /* True for DESCENDING sort order */
-    } ak;
+    } al;
     struct OP_Or_stack_vars {
       int v1;    /* Left operand:  0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
       int v2;    /* Right operand: 0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
-    } al;
+    } am;
     struct OP_IfNot_stack_vars {
       int c;
-    } am;
+    } an;
     struct OP_Column_stack_vars {
       u32 payloadSize;   /* Number of bytes in the record */
       i64 payloadSize64; /* Number of bytes in the record */
@@ -65976,11 +65666,11 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       int avail;         /* Number of bytes of available data */
       u32 t;             /* A type code from the record header */
       Mem *pReg;         /* PseudoTable input register */
-    } an;
+    } ao;
     struct OP_Affinity_stack_vars {
       const char *zAffinity;   /* The affinity to be applied */
       char cAff;               /* A single character of affinity */
-    } ao;
+    } ap;
     struct OP_MakeRecord_stack_vars {
       u8 *zNewRecord;        /* A buffer to hold the data for the new record */
       Mem *pRec;             /* The new record */
@@ -65997,11 +65687,11 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       int file_format;       /* File format to use for encoding */
       int i;                 /* Space used in zNewRecord[] */
       int len;               /* Length of a field */
-    } ap;
+    } aq;
     struct OP_Count_stack_vars {
       i64 nEntry;
       BtCursor *pCrsr;
-    } aq;
+    } ar;
     struct OP_Savepoint_stack_vars {
       int p1;                         /* Value of P1 operand */
       char *zName;                    /* Name of savepoint */
@@ -66011,28 +65701,28 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       Savepoint *pTmp;
       int iSavepoint;
       int ii;
-    } ar;
+    } as;
     struct OP_AutoCommit_stack_vars {
       int desiredAutoCommit;
       int iRollback;
       int turnOnAC;
-    } as;
+    } at;
     struct OP_Transaction_stack_vars {
       Btree *pBt;
-    } at;
+    } au;
     struct OP_ReadCookie_stack_vars {
       int iMeta;
       int iDb;
       int iCookie;
-    } au;
+    } av;
     struct OP_SetCookie_stack_vars {
       Db *pDb;
-    } av;
+    } aw;
     struct OP_VerifyCookie_stack_vars {
       int iMeta;
       int iGen;
       Btree *pBt;
-    } aw;
+    } ax;
     struct OP_OpenWrite_stack_vars {
       int nField;
       KeyInfo *pKeyInfo;
@@ -66042,16 +65732,16 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       Btree *pX;
       VdbeCursor *pCur;
       Db *pDb;
-    } ax;
+    } ay;
     struct OP_OpenEphemeral_stack_vars {
       VdbeCursor *pCx;
-    } ay;
+    } az;
     struct OP_SorterOpen_stack_vars {
       VdbeCursor *pCx;
-    } az;
+    } ba;
     struct OP_OpenPseudo_stack_vars {
       VdbeCursor *pCx;
-    } ba;
+    } bb;
     struct OP_SeekGt_stack_vars {
       int res;
       int oc;
@@ -66059,10 +65749,10 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       UnpackedRecord r;
       int nField;
       i64 iKey;      /* The rowid we are to seek to */
-    } bb;
+    } bc;
     struct OP_Seek_stack_vars {
       VdbeCursor *pC;
-    } bc;
+    } bd;
     struct OP_Found_stack_vars {
       int alreadyExists;
       VdbeCursor *pC;
@@ -66071,7 +65761,7 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       UnpackedRecord *pIdxKey;
       UnpackedRecord r;
       char aTempRec[ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*3 + 7];
-    } bd;
+    } be;
     struct OP_IsUnique_stack_vars {
       u16 ii;
       VdbeCursor *pCx;
@@ -66080,13 +65770,13 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       Mem *aMx;
       UnpackedRecord r;                  /* B-Tree index search key */
       i64 R;                             /* Rowid stored in register P3 */
-    } be;
+    } bf;
     struct OP_NotExists_stack_vars {
       VdbeCursor *pC;
       BtCursor *pCrsr;
       int res;
       u64 iKey;
-    } bf;
+    } bg;
     struct OP_NewRowid_stack_vars {
       i64 v;                 /* The new rowid */
       VdbeCursor *pC;        /* Cursor of table to get the new rowid */
@@ -66094,7 +65784,7 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       int cnt;               /* Counter to limit the number of searches */
       Mem *pMem;             /* Register holding largest rowid for AUTOINCREMENT */
       VdbeFrame *pFrame;     /* Root frame of VDBE */
-    } bg;
+    } bh;
     struct OP_InsertInt_stack_vars {
       Mem *pData;       /* MEM cell holding data for the record to be inserted */
       Mem *pKey;        /* MEM cell holding key  for the record */
@@ -66105,89 +65795,89 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       const char *zDb;  /* database name - used by the update hook */
       const char *zTbl; /* Table name - used by the opdate hook */
       int op;           /* Opcode for update hook: SQLITE_UPDATE or SQLITE_INSERT */
-    } bh;
+    } bi;
     struct OP_Delete_stack_vars {
       i64 iKey;
       VdbeCursor *pC;
-    } bi;
+    } bj;
     struct OP_SorterCompare_stack_vars {
       VdbeCursor *pC;
       int res;
-    } bj;
+    } bk;
     struct OP_SorterData_stack_vars {
       VdbeCursor *pC;
-    } bk;
+    } bl;
     struct OP_RowData_stack_vars {
       VdbeCursor *pC;
       BtCursor *pCrsr;
       u32 n;
       i64 n64;
-    } bl;
+    } bm;
     struct OP_Rowid_stack_vars {
       VdbeCursor *pC;
       i64 v;
       sqlite3_vtab *pVtab;
       const sqlite3_module *pModule;
-    } bm;
+    } bn;
     struct OP_NullRow_stack_vars {
       VdbeCursor *pC;
-    } bn;
+    } bo;
     struct OP_Last_stack_vars {
       VdbeCursor *pC;
       BtCursor *pCrsr;
       int res;
-    } bo;
+    } bp;
     struct OP_Rewind_stack_vars {
       VdbeCursor *pC;
       BtCursor *pCrsr;
       int res;
-    } bp;
+    } bq;
     struct OP_Next_stack_vars {
       VdbeCursor *pC;
       int res;
-    } bq;
+    } br;
     struct OP_IdxInsert_stack_vars {
       VdbeCursor *pC;
       BtCursor *pCrsr;
       int nKey;
       const char *zKey;
-    } br;
+    } bs;
     struct OP_IdxDelete_stack_vars {
       VdbeCursor *pC;
       BtCursor *pCrsr;
       int res;
       UnpackedRecord r;
-    } bs;
+    } bt;
     struct OP_IdxRowid_stack_vars {
       BtCursor *pCrsr;
       VdbeCursor *pC;
       i64 rowid;
-    } bt;
+    } bu;
     struct OP_IdxGE_stack_vars {
       VdbeCursor *pC;
       int res;
       UnpackedRecord r;
-    } bu;
+    } bv;
     struct OP_Destroy_stack_vars {
       int iMoved;
       int iCnt;
       Vdbe *pVdbe;
       int iDb;
-    } bv;
+    } bw;
     struct OP_Clear_stack_vars {
       int nChange;
-    } bw;
+    } bx;
     struct OP_CreateTable_stack_vars {
       int pgno;
       int flags;
       Db *pDb;
-    } bx;
+    } by;
     struct OP_ParseSchema_stack_vars {
       int iDb;
       const char *zMaster;
       char *zSql;
       InitData initData;
-    } by;
+    } bz;
     struct OP_IntegrityCk_stack_vars {
       int nRoot;      /* Number of tables to check.  (Number of root pages.) */
       int *aRoot;     /* Array of rootpage numbers for tables to be checked */
@@ -66195,14 +65885,14 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       int nErr;       /* Number of errors reported */
       char *z;        /* Text of the error report */
       Mem *pnErr;     /* Register keeping track of errors remaining */
-    } bz;
+    } ca;
     struct OP_RowSetRead_stack_vars {
       i64 val;
-    } ca;
+    } cb;
     struct OP_RowSetTest_stack_vars {
       int iSet;
       int exists;
-    } cb;
+    } cc;
     struct OP_Program_stack_vars {
       int nMem;               /* Number of memory registers for sub-program */
       int nByte;              /* Bytes of runtime space required for sub-program */
@@ -66212,15 +65902,15 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       VdbeFrame *pFrame;      /* New vdbe frame to execute in */
       SubProgram *pProgram;   /* Sub-program to execute */
       void *t;                /* Token identifying trigger */
-    } cc;
+    } cd;
     struct OP_Param_stack_vars {
       VdbeFrame *pFrame;
       Mem *pIn;
-    } cd;
+    } ce;
     struct OP_MemMax_stack_vars {
       Mem *pIn1;
       VdbeFrame *pFrame;
-    } ce;
+    } cf;
     struct OP_AggStep_stack_vars {
       int n;
       int i;
@@ -66228,34 +65918,36 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       Mem *pRec;
       sqlite3_context ctx;
       sqlite3_value **apVal;
-    } cf;
+    } cg;
     struct OP_AggFinal_stack_vars {
       Mem *pMem;
-    } cg;
+    } ch;
     struct OP_Checkpoint_stack_vars {
       int i;                          /* Loop counter */
       int aRes[3];                    /* Results */
       Mem *pMem;                      /* Write results here */
-    } ch;
+    } ci;
     struct OP_JournalMode_stack_vars {
       Btree *pBt;                     /* Btree to change journal mode of */
       Pager *pPager;                  /* Pager associated with pBt */
       int eNew;                       /* New journal mode */
       int eOld;                       /* The old journal mode */
+#ifndef SQLITE_OMIT_WAL
       const char *zFilename;          /* Name of database file for pPager */
-    } ci;
+#endif
+    } cj;
     struct OP_IncrVacuum_stack_vars {
       Btree *pBt;
-    } cj;
+    } ck;
     struct OP_VBegin_stack_vars {
       VTable *pVTab;
-    } ck;
+    } cl;
     struct OP_VOpen_stack_vars {
       VdbeCursor *pCur;
       sqlite3_vtab_cursor *pVtabCursor;
       sqlite3_vtab *pVtab;
       sqlite3_module *pModule;
-    } cl;
+    } cm;
     struct OP_VFilter_stack_vars {
       int nArg;
       int iQuery;
@@ -66268,23 +65960,23 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       int res;
       int i;
       Mem **apArg;
-    } cm;
+    } cn;
     struct OP_VColumn_stack_vars {
       sqlite3_vtab *pVtab;
       const sqlite3_module *pModule;
       Mem *pDest;
       sqlite3_context sContext;
-    } cn;
+    } co;
     struct OP_VNext_stack_vars {
       sqlite3_vtab *pVtab;
       const sqlite3_module *pModule;
       int res;
       VdbeCursor *pCur;
-    } co;
+    } cp;
     struct OP_VRename_stack_vars {
       sqlite3_vtab *pVtab;
       Mem *pName;
-    } cp;
+    } cq;
     struct OP_VUpdate_stack_vars {
       sqlite3_vtab *pVtab;
       sqlite3_module *pModule;
@@ -66293,11 +65985,11 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
       sqlite_int64 rowid;
       Mem **apArg;
       Mem *pX;
-    } cq;
+    } cr;
     struct OP_Trace_stack_vars {
       char *zTrace;
       char *z;
-    } cr;
+    } cs;
   } u;
   /* End automatically generated code
   ********************************************************************/
@@ -66310,6 +66002,7 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
     goto no_mem;
   }
   assert( p->rc==SQLITE_OK || p->rc==SQLITE_BUSY );
+  assert( p->bIsReader || p->readOnly!=0 );
   p->rc = SQLITE_OK;
   assert( p->explain==0 );
   p->pResultSet = 0;
@@ -66317,7 +66010,15 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
   CHECK_FOR_INTERRUPT;
   sqlite3VdbeIOTraceSql(p);
 #ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-  checkProgress = db->xProgress!=0;
+  if( db->xProgress ){
+    assert( 0 < db->nProgressOps );
+    nProgressLimit = (unsigned)p->aCounter[SQLITE_STMTSTATUS_VM_STEP];
+    if( nProgressLimit==0 ){
+      nProgressLimit = db->nProgressOps;
+    }else{
+      nProgressLimit %= (unsigned)db->nProgressOps;
+    }
+  }
 #endif
 #ifdef SQLITE_DEBUG
   sqlite3BeginBenignMalloc();
@@ -66338,6 +66039,7 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
     origPc = pc;
     start = sqlite3Hwtime();
 #endif
+    nVmStep++;
     pOp = &aOp[pc];
 
     /* Only allow tracing if SQLITE_DEBUG is defined.
@@ -66365,28 +66067,7 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
     }
 #endif
 
-#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
-    /* Call the progress callback if it is configured and the required number
-    ** of VDBE ops have been executed (either since this invocation of
-    ** sqlite3VdbeExec() or since last time the progress callback was called).
-    ** If the progress callback returns non-zero, exit the virtual machine with
-    ** a return code SQLITE_ABORT.
-    */
-    if( checkProgress ){
-      if( db->nProgressOps==nProgressOps ){
-        int prc;
-        prc = db->xProgress(db->pProgressArg);
-        if( prc!=0 ){
-          rc = SQLITE_INTERRUPT;
-          goto vdbe_error_halt;
-        }
-        nProgressOps = 0;
-      }
-      nProgressOps++;
-    }
-#endif
-
-    /* On any opcode with the "out2-prerelase" tag, free any
+    /* On any opcode with the "out2-prerelease" tag, free any
     ** external allocations out of mem[p2] and set mem[p2] to be
     ** an undefined integer.  Opcodes will either fill in the integer
     ** value or convert mem[p2] to a different type.
@@ -66478,8 +66159,40 @@ SQLITE_PRIVATE int sqlite3VdbeExec(
 ** the program.
 */
 case OP_Goto: {             /* jump */
-  CHECK_FOR_INTERRUPT;
   pc = pOp->p2 - 1;
+
+  /* Opcodes that are used as the bottom of a loop (OP_Next, OP_Prev,
+  ** OP_VNext, OP_RowSetNext, or OP_SorterNext) all jump here upon
+  ** completion.  Check to see if sqlite3_interrupt() has been called
+  ** or if the progress callback needs to be invoked. 
+  **
+  ** This code uses unstructured "goto" statements and does not look clean.
+  ** But that is not due to sloppy coding habits. The code is written this
+  ** way for performance, to avoid having to run the interrupt and progress
+  ** checks on every opcode.  This helps sqlite3_step() to run about 1.5%
+  ** faster according to "valgrind --tool=cachegrind" */
+check_for_interrupt:
+  CHECK_FOR_INTERRUPT;
+#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
+  /* Call the progress callback if it is configured and the required number
+  ** of VDBE ops have been executed (either since this invocation of
+  ** sqlite3VdbeExec() or since last time the progress callback was called).
+  ** If the progress callback returns non-zero, exit the virtual machine with
+  ** a return code SQLITE_ABORT.
+  */
+  if( db->xProgress!=0 && nVmStep>=nProgressLimit ){
+    int prc;
+    prc = db->xProgress(db->pProgressArg);
+    if( prc!=0 ){
+      rc = SQLITE_INTERRUPT;
+      goto vdbe_error_halt;
+    }
+    if( db->xProgress!=0 ){
+      nProgressLimit = nVmStep + db->nProgressOps - (nVmStep%db->nProgressOps);
+    }
+  }
+#endif
+  
   break;
 }
 
@@ -66599,8 +66312,8 @@ case OP_Halt: {
   if( rc==SQLITE_BUSY ){
     p->rc = rc = SQLITE_BUSY;
   }else{
-    assert( rc==SQLITE_OK || p->rc==SQLITE_CONSTRAINT );
-    assert( rc==SQLITE_OK || db->nDeferredCons>0 );
+    assert( rc==SQLITE_OK || (p->rc&0xff)==SQLITE_CONSTRAINT );
+    assert( rc==SQLITE_OK || db->nDeferredCons>0 || db->nDeferredImmCons>0 );
     rc = p->rc ? SQLITE_ERROR : SQLITE_DONE;
   }
   goto vdbe_return;
@@ -66688,25 +66401,30 @@ case OP_String: {          /* out2-prerelease */
   break;
 }
 
-/* Opcode: Null * P2 P3 * *
+/* Opcode: Null P1 P2 P3 * *
 **
 ** Write a NULL into registers P2.  If P3 greater than P2, then also write
-** NULL into register P3 and ever register in between P2 and P3.  If P3
+** NULL into register P3 and every register in between P2 and P3.  If P3
 ** is less than P2 (typically P3 is zero) then only register P2 is
-** set to NULL
+** set to NULL.
+**
+** If the P1 value is non-zero, then also set the MEM_Cleared flag so that
+** NULL values will not compare equal even if SQLITE_NULLEQ is set on
+** OP_Ne or OP_Eq.
 */
 case OP_Null: {           /* out2-prerelease */
 #if 0  /* local variables moved into u.ab */
   int cnt;
+  u16 nullFlag;
 #endif /* local variables moved into u.ab */
   u.ab.cnt = pOp->p3-pOp->p2;
   assert( pOp->p3<=p->nMem );
-  pOut->flags = MEM_Null;
+  pOut->flags = u.ab.nullFlag = pOp->p1 ? (MEM_Null|MEM_Cleared) : MEM_Null;
   while( u.ab.cnt>0 ){
     pOut++;
     memAboutToChange(p, pOut);
     VdbeMemRelease(pOut);
-    pOut->flags = MEM_Null;
+    pOut->flags = u.ab.nullFlag;
     u.ab.cnt--;
   }
   break;
@@ -66751,10 +66469,10 @@ case OP_Variable: {            /* out2-prerelease */
 
 /* Opcode: Move P1 P2 P3 * *
 **
-** Move the values in register P1..P1+P3-1 over into
-** registers P2..P2+P3-1.  Registers P1..P1+P1-1 are
+** Move the values in register P1..P1+P3 over into
+** registers P2..P2+P3.  Registers P1..P1+P3 are
 ** left holding a NULL.  It is an error for register ranges
-** P1..P1+P3-1 and P2..P2+P3-1 to overlap.
+** P1..P1+P3 and P2..P2+P3 to overlap.
 */
 case OP_Move: {
 #if 0  /* local variables moved into u.ad */
@@ -66764,7 +66482,7 @@ case OP_Move: {
   int p2;          /* Register to copy to */
 #endif /* local variables moved into u.ad */
 
-  u.ad.n = pOp->p3;
+  u.ad.n = pOp->p3 + 1;
   u.ad.p1 = pOp->p1;
   u.ad.p2 = pOp->p2;
   assert( u.ad.n>0 && u.ad.p1>0 && u.ad.p2>0 );
@@ -66793,20 +66511,33 @@ case OP_Move: {
   break;
 }
 
-/* Opcode: Copy P1 P2 * * *
+/* Opcode: Copy P1 P2 P3 * *
 **
-** Make a copy of register P1 into register P2.
+** Make a copy of registers P1..P1+P3 into registers P2..P2+P3.
 **
 ** This instruction makes a deep copy of the value.  A duplicate
 ** is made of any string or blob constant.  See also OP_SCopy.
 */
-case OP_Copy: {             /* in1, out2 */
+case OP_Copy: {
+#if 0  /* local variables moved into u.ae */
+  int n;
+#endif /* local variables moved into u.ae */
+
+  u.ae.n = pOp->p3;
   pIn1 = &aMem[pOp->p1];
   pOut = &aMem[pOp->p2];
   assert( pOut!=pIn1 );
-  sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
-  Deephemeralize(pOut);
-  REGISTER_TRACE(pOp->p2, pOut);
+  while( 1 ){
+    sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
+    Deephemeralize(pOut);
+#ifdef SQLITE_DEBUG
+    pOut->pScopyFrom = 0;
+#endif
+    REGISTER_TRACE(pOp->p2+pOp->p3-u.ae.n, pOut);
+    if( (u.ae.n--)==0 ) break;
+    pOut++;
+    pIn1++;
+  }
   break;
 }
 
@@ -66843,10 +66574,10 @@ case OP_SCopy: {            /* in1, out2 */
 ** row.
 */
 case OP_ResultRow: {
-#if 0  /* local variables moved into u.ae */
+#if 0  /* local variables moved into u.af */
   Mem *pMem;
   int i;
-#endif /* local variables moved into u.ae */
+#endif /* local variables moved into u.af */
   assert( p->nResColumn==pOp->p2 );
   assert( pOp->p1>0 );
   assert( pOp->p1+pOp->p2<=p->nMem+1 );
@@ -66888,15 +66619,15 @@ case OP_ResultRow: {
   ** and have an assigned type.  The results are de-ephemeralized as
   ** a side effect.
   */
-  u.ae.pMem = p->pResultSet = &aMem[pOp->p1];
-  for(u.ae.i=0; u.ae.i<pOp->p2; u.ae.i++){
-    assert( memIsValid(&u.ae.pMem[u.ae.i]) );
-    Deephemeralize(&u.ae.pMem[u.ae.i]);
-    assert( (u.ae.pMem[u.ae.i].flags & MEM_Ephem)==0
-            || (u.ae.pMem[u.ae.i].flags & (MEM_Str|MEM_Blob))==0 );
-    sqlite3VdbeMemNulTerminate(&u.ae.pMem[u.ae.i]);
-    sqlite3VdbeMemStoreType(&u.ae.pMem[u.ae.i]);
-    REGISTER_TRACE(pOp->p1+u.ae.i, &u.ae.pMem[u.ae.i]);
+  u.af.pMem = p->pResultSet = &aMem[pOp->p1];
+  for(u.af.i=0; u.af.i<pOp->p2; u.af.i++){
+    assert( memIsValid(&u.af.pMem[u.af.i]) );
+    Deephemeralize(&u.af.pMem[u.af.i]);
+    assert( (u.af.pMem[u.af.i].flags & MEM_Ephem)==0
+            || (u.af.pMem[u.af.i].flags & (MEM_Str|MEM_Blob))==0 );
+    sqlite3VdbeMemNulTerminate(&u.af.pMem[u.af.i]);
+    sqlite3VdbeMemStoreType(&u.af.pMem[u.af.i]);
+    REGISTER_TRACE(pOp->p1+u.af.i, &u.af.pMem[u.af.i]);
   }
   if( db->mallocFailed ) goto no_mem;
 
@@ -66920,9 +66651,9 @@ case OP_ResultRow: {
 ** to avoid a memcpy().
 */
 case OP_Concat: {           /* same as TK_CONCAT, in1, in2, out3 */
-#if 0  /* local variables moved into u.af */
+#if 0  /* local variables moved into u.ag */
   i64 nByte;
-#endif /* local variables moved into u.af */
+#endif /* local variables moved into u.ag */
 
   pIn1 = &aMem[pOp->p1];
   pIn2 = &aMem[pOp->p2];
@@ -66935,22 +66666,22 @@ case OP_Concat: {           /* same as TK_CONCAT, in1, in2, out3 */
   if( ExpandBlob(pIn1) || ExpandBlob(pIn2) ) goto no_mem;
   Stringify(pIn1, encoding);
   Stringify(pIn2, encoding);
-  u.af.nByte = pIn1->n + pIn2->n;
-  if( u.af.nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+  u.ag.nByte = pIn1->n + pIn2->n;
+  if( u.ag.nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
     goto too_big;
   }
   MemSetTypeFlag(pOut, MEM_Str);
-  if( sqlite3VdbeMemGrow(pOut, (int)u.af.nByte+2, pOut==pIn2) ){
+  if( sqlite3VdbeMemGrow(pOut, (int)u.ag.nByte+2, pOut==pIn2) ){
     goto no_mem;
   }
   if( pOut!=pIn2 ){
     memcpy(pOut->z, pIn2->z, pIn2->n);
   }
   memcpy(&pOut->z[pIn2->n], pIn1->z, pIn1->n);
-  pOut->z[u.af.nByte] = 0;
-  pOut->z[u.af.nByte+1] = 0;
+  pOut->z[u.ag.nByte] = 0;
+  pOut->z[u.ag.nByte+1] = 0;
   pOut->flags |= MEM_Term;
-  pOut->n = (int)u.af.nByte;
+  pOut->n = (int)u.ag.nByte;
   pOut->enc = encoding;
   UPDATE_MAX_BLOBSIZE(pOut);
   break;
@@ -66994,76 +66725,79 @@ case OP_Subtract:              /* same as TK_MINUS, in1, in2, out3 */
 case OP_Multiply:              /* same as TK_STAR, in1, in2, out3 */
 case OP_Divide:                /* same as TK_SLASH, in1, in2, out3 */
 case OP_Remainder: {           /* same as TK_REM, in1, in2, out3 */
-#if 0  /* local variables moved into u.ag */
+#if 0  /* local variables moved into u.ah */
+  char bIntint;   /* Started out as two integer operands */
   int flags;      /* Combined MEM_* flags from both inputs */
   i64 iA;         /* Integer value of left operand */
   i64 iB;         /* Integer value of right operand */
   double rA;      /* Real value of left operand */
   double rB;      /* Real value of right operand */
-#endif /* local variables moved into u.ag */
+#endif /* local variables moved into u.ah */
 
   pIn1 = &aMem[pOp->p1];
   applyNumericAffinity(pIn1);
   pIn2 = &aMem[pOp->p2];
   applyNumericAffinity(pIn2);
   pOut = &aMem[pOp->p3];
-  u.ag.flags = pIn1->flags | pIn2->flags;
-  if( (u.ag.flags & MEM_Null)!=0 ) goto arithmetic_result_is_null;
+  u.ah.flags = pIn1->flags | pIn2->flags;
+  if( (u.ah.flags & MEM_Null)!=0 ) goto arithmetic_result_is_null;
   if( (pIn1->flags & pIn2->flags & MEM_Int)==MEM_Int ){
-    u.ag.iA = pIn1->u.i;
-    u.ag.iB = pIn2->u.i;
+    u.ah.iA = pIn1->u.i;
+    u.ah.iB = pIn2->u.i;
+    u.ah.bIntint = 1;
     switch( pOp->opcode ){
-      case OP_Add:       if( sqlite3AddInt64(&u.ag.iB,u.ag.iA) ) goto fp_math;  break;
-      case OP_Subtract:  if( sqlite3SubInt64(&u.ag.iB,u.ag.iA) ) goto fp_math;  break;
-      case OP_Multiply:  if( sqlite3MulInt64(&u.ag.iB,u.ag.iA) ) goto fp_math;  break;
+      case OP_Add:       if( sqlite3AddInt64(&u.ah.iB,u.ah.iA) ) goto fp_math;  break;
+      case OP_Subtract:  if( sqlite3SubInt64(&u.ah.iB,u.ah.iA) ) goto fp_math;  break;
+      case OP_Multiply:  if( sqlite3MulInt64(&u.ah.iB,u.ah.iA) ) goto fp_math;  break;
       case OP_Divide: {
-        if( u.ag.iA==0 ) goto arithmetic_result_is_null;
-        if( u.ag.iA==-1 && u.ag.iB==SMALLEST_INT64 ) goto fp_math;
-        u.ag.iB /= u.ag.iA;
+        if( u.ah.iA==0 ) goto arithmetic_result_is_null;
+        if( u.ah.iA==-1 && u.ah.iB==SMALLEST_INT64 ) goto fp_math;
+        u.ah.iB /= u.ah.iA;
         break;
       }
       default: {
-        if( u.ag.iA==0 ) goto arithmetic_result_is_null;
-        if( u.ag.iA==-1 ) u.ag.iA = 1;
-        u.ag.iB %= u.ag.iA;
+        if( u.ah.iA==0 ) goto arithmetic_result_is_null;
+        if( u.ah.iA==-1 ) u.ah.iA = 1;
+        u.ah.iB %= u.ah.iA;
         break;
       }
     }
-    pOut->u.i = u.ag.iB;
+    pOut->u.i = u.ah.iB;
     MemSetTypeFlag(pOut, MEM_Int);
   }else{
+    u.ah.bIntint = 0;
 fp_math:
-    u.ag.rA = sqlite3VdbeRealValue(pIn1);
-    u.ag.rB = sqlite3VdbeRealValue(pIn2);
+    u.ah.rA = sqlite3VdbeRealValue(pIn1);
+    u.ah.rB = sqlite3VdbeRealValue(pIn2);
     switch( pOp->opcode ){
-      case OP_Add:         u.ag.rB += u.ag.rA;       break;
-      case OP_Subtract:    u.ag.rB -= u.ag.rA;       break;
-      case OP_Multiply:    u.ag.rB *= u.ag.rA;       break;
+      case OP_Add:         u.ah.rB += u.ah.rA;       break;
+      case OP_Subtract:    u.ah.rB -= u.ah.rA;       break;
+      case OP_Multiply:    u.ah.rB *= u.ah.rA;       break;
       case OP_Divide: {
         /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
-        if( u.ag.rA==(double)0 ) goto arithmetic_result_is_null;
-        u.ag.rB /= u.ag.rA;
+        if( u.ah.rA==(double)0 ) goto arithmetic_result_is_null;
+        u.ah.rB /= u.ah.rA;
         break;
       }
       default: {
-        u.ag.iA = (i64)u.ag.rA;
-        u.ag.iB = (i64)u.ag.rB;
-        if( u.ag.iA==0 ) goto arithmetic_result_is_null;
-        if( u.ag.iA==-1 ) u.ag.iA = 1;
-        u.ag.rB = (double)(u.ag.iB % u.ag.iA);
+        u.ah.iA = (i64)u.ah.rA;
+        u.ah.iB = (i64)u.ah.rB;
+        if( u.ah.iA==0 ) goto arithmetic_result_is_null;
+        if( u.ah.iA==-1 ) u.ah.iA = 1;
+        u.ah.rB = (double)(u.ah.iB % u.ah.iA);
         break;
       }
     }
 #ifdef SQLITE_OMIT_FLOATING_POINT
-    pOut->u.i = u.ag.rB;
+    pOut->u.i = u.ah.rB;
     MemSetTypeFlag(pOut, MEM_Int);
 #else
-    if( sqlite3IsNaN(u.ag.rB) ){
+    if( sqlite3IsNaN(u.ah.rB) ){
       goto arithmetic_result_is_null;
     }
-    pOut->r = u.ag.rB;
+    pOut->r = u.ah.rB;
     MemSetTypeFlag(pOut, MEM_Real);
-    if( (u.ag.flags & MEM_Real)==0 ){
+    if( (u.ah.flags & MEM_Real)==0 && !u.ah.bIntint ){
       sqlite3VdbeIntegerAffinity(pOut);
     }
 #endif
@@ -67115,92 +66849,81 @@ case OP_CollSeq: {
 ** See also: AggStep and AggFinal
 */
 case OP_Function: {
-#if 0  /* local variables moved into u.ah */
+#if 0  /* local variables moved into u.ai */
   int i;
   Mem *pArg;
   sqlite3_context ctx;
   sqlite3_value **apVal;
   int n;
-#endif /* local variables moved into u.ah */
+#endif /* local variables moved into u.ai */
 
-  u.ah.n = pOp->p5;
-  u.ah.apVal = p->apArg;
-  assert( u.ah.apVal || u.ah.n==0 );
+  u.ai.n = pOp->p5;
+  u.ai.apVal = p->apArg;
+  assert( u.ai.apVal || u.ai.n==0 );
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
   pOut = &aMem[pOp->p3];
   memAboutToChange(p, pOut);
 
-  assert( u.ah.n==0 || (pOp->p2>0 && pOp->p2+u.ah.n<=p->nMem+1) );
-  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+u.ah.n );
-  u.ah.pArg = &aMem[pOp->p2];
-  for(u.ah.i=0; u.ah.i<u.ah.n; u.ah.i++, u.ah.pArg++){
-    assert( memIsValid(u.ah.pArg) );
-    u.ah.apVal[u.ah.i] = u.ah.pArg;
-    Deephemeralize(u.ah.pArg);
-    sqlite3VdbeMemStoreType(u.ah.pArg);
-    REGISTER_TRACE(pOp->p2+u.ah.i, u.ah.pArg);
+  assert( u.ai.n==0 || (pOp->p2>0 && pOp->p2+u.ai.n<=p->nMem+1) );
+  assert( pOp->p3<pOp->p2 || pOp->p3>=pOp->p2+u.ai.n );
+  u.ai.pArg = &aMem[pOp->p2];
+  for(u.ai.i=0; u.ai.i<u.ai.n; u.ai.i++, u.ai.pArg++){
+    assert( memIsValid(u.ai.pArg) );
+    u.ai.apVal[u.ai.i] = u.ai.pArg;
+    Deephemeralize(u.ai.pArg);
+    sqlite3VdbeMemStoreType(u.ai.pArg);
+    REGISTER_TRACE(pOp->p2+u.ai.i, u.ai.pArg);
   }
 
-  assert( pOp->p4type==P4_FUNCDEF || pOp->p4type==P4_VDBEFUNC );
-  if( pOp->p4type==P4_FUNCDEF ){
-    u.ah.ctx.pFunc = pOp->p4.pFunc;
-    u.ah.ctx.pVdbeFunc = 0;
-  }else{
-    u.ah.ctx.pVdbeFunc = (VdbeFunc*)pOp->p4.pVdbeFunc;
-    u.ah.ctx.pFunc = u.ah.ctx.pVdbeFunc->pFunc;
-  }
-
-  u.ah.ctx.s.flags = MEM_Null;
-  u.ah.ctx.s.db = db;
-  u.ah.ctx.s.xDel = 0;
-  u.ah.ctx.s.zMalloc = 0;
+  assert( pOp->p4type==P4_FUNCDEF );
+  u.ai.ctx.pFunc = pOp->p4.pFunc;
+  u.ai.ctx.s.flags = MEM_Null;
+  u.ai.ctx.s.db = db;
+  u.ai.ctx.s.xDel = 0;
+  u.ai.ctx.s.zMalloc = 0;
+  u.ai.ctx.iOp = pc;
+  u.ai.ctx.pVdbe = p;
 
   /* The output cell may already have a buffer allocated. Move
-  ** the pointer to u.ah.ctx.s so in case the user-function can use
+  ** the pointer to u.ai.ctx.s so in case the user-function can use
   ** the already allocated buffer instead of allocating a new one.
   */
-  sqlite3VdbeMemMove(&u.ah.ctx.s, pOut);
-  MemSetTypeFlag(&u.ah.ctx.s, MEM_Null);
+  sqlite3VdbeMemMove(&u.ai.ctx.s, pOut);
+  MemSetTypeFlag(&u.ai.ctx.s, MEM_Null);
 
-  u.ah.ctx.isError = 0;
-  if( u.ah.ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
+  u.ai.ctx.fErrorOrAux = 0;
+  if( u.ai.ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
     assert( pOp>aOp );
     assert( pOp[-1].p4type==P4_COLLSEQ );
     assert( pOp[-1].opcode==OP_CollSeq );
-    u.ah.ctx.pColl = pOp[-1].p4.pColl;
+    u.ai.ctx.pColl = pOp[-1].p4.pColl;
   }
   db->lastRowid = lastRowid;
-  (*u.ah.ctx.pFunc->xFunc)(&u.ah.ctx, u.ah.n, u.ah.apVal); /* IMP: R-24505-23230 */
+  (*u.ai.ctx.pFunc->xFunc)(&u.ai.ctx, u.ai.n, u.ai.apVal); /* IMP: R-24505-23230 */
   lastRowid = db->lastRowid;
 
-  /* If any auxiliary data functions have been called by this user function,
-  ** immediately call the destructor for any non-static values.
-  */
-  if( u.ah.ctx.pVdbeFunc ){
-    sqlite3VdbeDeleteAuxData(u.ah.ctx.pVdbeFunc, pOp->p1);
-    pOp->p4.pVdbeFunc = u.ah.ctx.pVdbeFunc;
-    pOp->p4type = P4_VDBEFUNC;
-  }
-
   if( db->mallocFailed ){
     /* Even though a malloc() has failed, the implementation of the
     ** user function may have called an sqlite3_result_XXX() function
     ** to return a value. The following call releases any resources
     ** associated with such a value.
     */
-    sqlite3VdbeMemRelease(&u.ah.ctx.s);
+    sqlite3VdbeMemRelease(&u.ai.ctx.s);
     goto no_mem;
   }
 
   /* If the function returned an error, throw an exception */
-  if( u.ah.ctx.isError ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&u.ah.ctx.s));
-    rc = u.ah.ctx.isError;
+  if( u.ai.ctx.fErrorOrAux ){
+    if( u.ai.ctx.isError ){
+      sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&u.ai.ctx.s));
+      rc = u.ai.ctx.isError;
+    }
+    sqlite3VdbeDeleteAuxData(p, pc, pOp->p1);
   }
 
   /* Copy the result of the function into register P3 */
-  sqlite3VdbeChangeEncoding(&u.ah.ctx.s, encoding);
-  sqlite3VdbeMemMove(pOut, &u.ah.ctx.s);
+  sqlite3VdbeChangeEncoding(&u.ai.ctx.s, encoding);
+  sqlite3VdbeMemMove(pOut, &u.ai.ctx.s);
   if( sqlite3VdbeMemTooBig(pOut) ){
     goto too_big;
   }
@@ -67248,12 +66971,12 @@ case OP_BitAnd:                 /* same as TK_BITAND, in1, in2, out3 */
 case OP_BitOr:                  /* same as TK_BITOR, in1, in2, out3 */
 case OP_ShiftLeft:              /* same as TK_LSHIFT, in1, in2, out3 */
 case OP_ShiftRight: {           /* same as TK_RSHIFT, in1, in2, out3 */
-#if 0  /* local variables moved into u.ai */
+#if 0  /* local variables moved into u.aj */
   i64 iA;
   u64 uA;
   i64 iB;
   u8 op;
-#endif /* local variables moved into u.ai */
+#endif /* local variables moved into u.aj */
 
   pIn1 = &aMem[pOp->p1];
   pIn2 = &aMem[pOp->p2];
@@ -67262,38 +66985,38 @@ case OP_ShiftRight: {           /* same as TK_RSHIFT, in1, in2, out3 */
     sqlite3VdbeMemSetNull(pOut);
     break;
   }
-  u.ai.iA = sqlite3VdbeIntValue(pIn2);
-  u.ai.iB = sqlite3VdbeIntValue(pIn1);
-  u.ai.op = pOp->opcode;
-  if( u.ai.op==OP_BitAnd ){
-    u.ai.iA &= u.ai.iB;
-  }else if( u.ai.op==OP_BitOr ){
-    u.ai.iA |= u.ai.iB;
-  }else if( u.ai.iB!=0 ){
-    assert( u.ai.op==OP_ShiftRight || u.ai.op==OP_ShiftLeft );
+  u.aj.iA = sqlite3VdbeIntValue(pIn2);
+  u.aj.iB = sqlite3VdbeIntValue(pIn1);
+  u.aj.op = pOp->opcode;
+  if( u.aj.op==OP_BitAnd ){
+    u.aj.iA &= u.aj.iB;
+  }else if( u.aj.op==OP_BitOr ){
+    u.aj.iA |= u.aj.iB;
+  }else if( u.aj.iB!=0 ){
+    assert( u.aj.op==OP_ShiftRight || u.aj.op==OP_ShiftLeft );
 
     /* If shifting by a negative amount, shift in the other direction */
-    if( u.ai.iB<0 ){
+    if( u.aj.iB<0 ){
       assert( OP_ShiftRight==OP_ShiftLeft+1 );
-      u.ai.op = 2*OP_ShiftLeft + 1 - u.ai.op;
-      u.ai.iB = u.ai.iB>(-64) ? -u.ai.iB : 64;
+      u.aj.op = 2*OP_ShiftLeft + 1 - u.aj.op;
+      u.aj.iB = u.aj.iB>(-64) ? -u.aj.iB : 64;
     }
 
-    if( u.ai.iB>=64 ){
-      u.ai.iA = (u.ai.iA>=0 || u.ai.op==OP_ShiftLeft) ? 0 : -1;
+    if( u.aj.iB>=64 ){
+      u.aj.iA = (u.aj.iA>=0 || u.aj.op==OP_ShiftLeft) ? 0 : -1;
     }else{
-      memcpy(&u.ai.uA, &u.ai.iA, sizeof(u.ai.uA));
-      if( u.ai.op==OP_ShiftLeft ){
-        u.ai.uA <<= u.ai.iB;
+      memcpy(&u.aj.uA, &u.aj.iA, sizeof(u.aj.uA));
+      if( u.aj.op==OP_ShiftLeft ){
+        u.aj.uA <<= u.aj.iB;
       }else{
-        u.ai.uA >>= u.ai.iB;
+        u.aj.uA >>= u.aj.iB;
         /* Sign-extend on a right shift of a negative number */
-        if( u.ai.iA<0 ) u.ai.uA |= ((((u64)0xffffffff)<<32)|0xffffffff) << (64-u.ai.iB);
+        if( u.aj.iA<0 ) u.aj.uA |= ((((u64)0xffffffff)<<32)|0xffffffff) << (64-u.aj.iB);
       }
-      memcpy(&u.ai.iA, &u.ai.uA, sizeof(u.ai.iA));
+      memcpy(&u.aj.iA, &u.aj.uA, sizeof(u.aj.iA));
     }
   }
-  pOut->u.i = u.ai.iA;
+  pOut->u.i = u.aj.iA;
   MemSetTypeFlag(pOut, MEM_Int);
   break;
 }
@@ -67485,6 +67208,10 @@ case OP_ToReal: {                  /* same as TK_TO_REAL, in1 */
 **
 ** If the SQLITE_STOREP2 bit of P5 is set, then do not jump.  Instead,
 ** store a boolean result (either 0, or 1, or NULL) in register P2.
+**
+** If the SQLITE_NULLEQ bit is set in P5, then NULL values are considered
+** equal to one another, provided that they do not have their MEM_Cleared
+** bit set.
 */
 /* Opcode: Ne P1 P2 P3 P4 P5
 **
@@ -67534,18 +67261,18 @@ case OP_Lt:               /* same as TK_LT, jump, in1, in3 */
 case OP_Le:               /* same as TK_LE, jump, in1, in3 */
 case OP_Gt:               /* same as TK_GT, jump, in1, in3 */
 case OP_Ge: {             /* same as TK_GE, jump, in1, in3 */
-#if 0  /* local variables moved into u.aj */
+#if 0  /* local variables moved into u.ak */
   int res;            /* Result of the comparison of pIn1 against pIn3 */
   char affinity;      /* Affinity to use for comparison */
   u16 flags1;         /* Copy of initial value of pIn1->flags */
   u16 flags3;         /* Copy of initial value of pIn3->flags */
-#endif /* local variables moved into u.aj */
+#endif /* local variables moved into u.ak */
 
   pIn1 = &aMem[pOp->p1];
   pIn3 = &aMem[pOp->p3];
-  u.aj.flags1 = pIn1->flags;
-  u.aj.flags3 = pIn3->flags;
-  if( (u.aj.flags1 | u.aj.flags3)&MEM_Null ){
+  u.ak.flags1 = pIn1->flags;
+  u.ak.flags3 = pIn3->flags;
+  if( (u.ak.flags1 | u.ak.flags3)&MEM_Null ){
     /* One or both operands are NULL */
     if( pOp->p5 & SQLITE_NULLEQ ){
       /* If SQLITE_NULLEQ is set (which will only happen if the operator is
@@ -67553,57 +67280,65 @@ case OP_Ge: {             /* same as TK_GE, jump, in1, in3 */
       ** or not both operands are null.
       */
       assert( pOp->opcode==OP_Eq || pOp->opcode==OP_Ne );
-      u.aj.res = (u.aj.flags1 & u.aj.flags3 & MEM_Null)==0;
+      assert( (u.ak.flags1 & MEM_Cleared)==0 );
+      if( (u.ak.flags1&MEM_Null)!=0
+       && (u.ak.flags3&MEM_Null)!=0
+       && (u.ak.flags3&MEM_Cleared)==0
+      ){
+        u.ak.res = 0;  /* Results are equal */
+      }else{
+        u.ak.res = 1;  /* Results are not equal */
+      }
     }else{
       /* SQLITE_NULLEQ is clear and at least one operand is NULL,
       ** then the result is always NULL.
       ** The jump is taken if the SQLITE_JUMPIFNULL bit is set.
       */
-      if( pOp->p5 & SQLITE_STOREP2 ){
+      if( pOp->p5 & SQLITE_JUMPIFNULL ){
+        pc = pOp->p2-1;
+      }else if( pOp->p5 & SQLITE_STOREP2 ){
         pOut = &aMem[pOp->p2];
         MemSetTypeFlag(pOut, MEM_Null);
         REGISTER_TRACE(pOp->p2, pOut);
-      }else if( pOp->p5 & SQLITE_JUMPIFNULL ){
-        pc = pOp->p2-1;
       }
       break;
     }
   }else{
     /* Neither operand is NULL.  Do a comparison. */
-    u.aj.affinity = pOp->p5 & SQLITE_AFF_MASK;
-    if( u.aj.affinity ){
-      applyAffinity(pIn1, u.aj.affinity, encoding);
-      applyAffinity(pIn3, u.aj.affinity, encoding);
+    u.ak.affinity = pOp->p5 & SQLITE_AFF_MASK;
+    if( u.ak.affinity ){
+      applyAffinity(pIn1, u.ak.affinity, encoding);
+      applyAffinity(pIn3, u.ak.affinity, encoding);
       if( db->mallocFailed ) goto no_mem;
     }
 
     assert( pOp->p4type==P4_COLLSEQ || pOp->p4.pColl==0 );
     ExpandBlob(pIn1);
     ExpandBlob(pIn3);
-    u.aj.res = sqlite3MemCompare(pIn3, pIn1, pOp->p4.pColl);
+    u.ak.res = sqlite3MemCompare(pIn3, pIn1, pOp->p4.pColl);
   }
   switch( pOp->opcode ){
-    case OP_Eq:    u.aj.res = u.aj.res==0;     break;
-    case OP_Ne:    u.aj.res = u.aj.res!=0;     break;
-    case OP_Lt:    u.aj.res = u.aj.res<0;      break;
-    case OP_Le:    u.aj.res = u.aj.res<=0;     break;
-    case OP_Gt:    u.aj.res = u.aj.res>0;      break;
-    default:       u.aj.res = u.aj.res>=0;     break;
+    case OP_Eq:    u.ak.res = u.ak.res==0;     break;
+    case OP_Ne:    u.ak.res = u.ak.res!=0;     break;
+    case OP_Lt:    u.ak.res = u.ak.res<0;      break;
+    case OP_Le:    u.ak.res = u.ak.res<=0;     break;
+    case OP_Gt:    u.ak.res = u.ak.res>0;      break;
+    default:       u.ak.res = u.ak.res>=0;     break;
   }
 
   if( pOp->p5 & SQLITE_STOREP2 ){
     pOut = &aMem[pOp->p2];
     memAboutToChange(p, pOut);
     MemSetTypeFlag(pOut, MEM_Int);
-    pOut->u.i = u.aj.res;
+    pOut->u.i = u.ak.res;
     REGISTER_TRACE(pOp->p2, pOut);
-  }else if( u.aj.res ){
+  }else if( u.ak.res ){
     pc = pOp->p2-1;
   }
 
   /* Undo any changes made by applyAffinity() to the input registers. */
-  pIn1->flags = (pIn1->flags&~MEM_TypeMask) | (u.aj.flags1&MEM_TypeMask);
-  pIn3->flags = (pIn3->flags&~MEM_TypeMask) | (u.aj.flags3&MEM_TypeMask);
+  pIn1->flags = (pIn1->flags&~MEM_TypeMask) | (u.ak.flags1&MEM_TypeMask);
+  pIn3->flags = (pIn3->flags&~MEM_TypeMask) | (u.ak.flags3&MEM_TypeMask);
   break;
 }
 
@@ -67612,9 +67347,9 @@ case OP_Ge: {             /* same as TK_GE, jump, in1, in3 */
 ** Set the permutation used by the OP_Compare operator to be the array
 ** of integers in P4.
 **
-** The permutation is only valid until the next OP_Permutation, OP_Compare,
-** OP_Halt, or OP_ResultRow.  Typically the OP_Permutation should occur
-** immediately prior to the OP_Compare.
+** The permutation is only valid until the next OP_Compare that has
+** the OPFLAG_PERMUTE bit set in P5. Typically the OP_Permutation should 
+** occur immediately prior to the OP_Compare.
 */
 case OP_Permutation: {
   assert( pOp->p4type==P4_INTARRAY );
@@ -67623,12 +67358,17 @@ case OP_Permutation: {
   break;
 }
 
-/* Opcode: Compare P1 P2 P3 P4 *
+/* Opcode: Compare P1 P2 P3 P4 P5
 **
 ** Compare two vectors of registers in reg(P1)..reg(P1+P3-1) (call this
 ** vector "A") and in reg(P2)..reg(P2+P3-1) ("B").  Save the result of
 ** the comparison for use by the next OP_Jump instruct.
 **
+** If P5 has the OPFLAG_PERMUTE bit set, then the order of comparison is
+** determined by the most recent OP_Permutation operator.  If the
+** OPFLAG_PERMUTE bit is clear, then register are compared in sequential
+** order.
+**
 ** P4 is a KeyInfo structure that defines collating sequences and sort
 ** orders for the comparison.  The permutation applies to registers
 ** only.  The KeyInfo elements are used sequentially.
@@ -67638,7 +67378,7 @@ case OP_Permutation: {
 ** and strings are less than blobs.
 */
 case OP_Compare: {
-#if 0  /* local variables moved into u.ak */
+#if 0  /* local variables moved into u.al */
   int n;
   int i;
   int p1;
@@ -67647,37 +67387,38 @@ case OP_Compare: {
   int idx;
   CollSeq *pColl;    /* Collating sequence to use on this term */
   int bRev;          /* True for DESCENDING sort order */
-#endif /* local variables moved into u.ak */
+#endif /* local variables moved into u.al */
 
-  u.ak.n = pOp->p3;
-  u.ak.pKeyInfo = pOp->p4.pKeyInfo;
-  assert( u.ak.n>0 );
-  assert( u.ak.pKeyInfo!=0 );
-  u.ak.p1 = pOp->p1;
-  u.ak.p2 = pOp->p2;
+  if( (pOp->p5 & OPFLAG_PERMUTE)==0 ) aPermute = 0;
+  u.al.n = pOp->p3;
+  u.al.pKeyInfo = pOp->p4.pKeyInfo;
+  assert( u.al.n>0 );
+  assert( u.al.pKeyInfo!=0 );
+  u.al.p1 = pOp->p1;
+  u.al.p2 = pOp->p2;
 #if SQLITE_DEBUG
   if( aPermute ){
     int k, mx = 0;
-    for(k=0; k<u.ak.n; k++) if( aPermute[k]>mx ) mx = aPermute[k];
-    assert( u.ak.p1>0 && u.ak.p1+mx<=p->nMem+1 );
-    assert( u.ak.p2>0 && u.ak.p2+mx<=p->nMem+1 );
+    for(k=0; k<u.al.n; k++) if( aPermute[k]>mx ) mx = aPermute[k];
+    assert( u.al.p1>0 && u.al.p1+mx<=p->nMem+1 );
+    assert( u.al.p2>0 && u.al.p2+mx<=p->nMem+1 );
   }else{
-    assert( u.ak.p1>0 && u.ak.p1+u.ak.n<=p->nMem+1 );
-    assert( u.ak.p2>0 && u.ak.p2+u.ak.n<=p->nMem+1 );
+    assert( u.al.p1>0 && u.al.p1+u.al.n<=p->nMem+1 );
+    assert( u.al.p2>0 && u.al.p2+u.al.n<=p->nMem+1 );
   }
 #endif /* SQLITE_DEBUG */
-  for(u.ak.i=0; u.ak.i<u.ak.n; u.ak.i++){
-    u.ak.idx = aPermute ? aPermute[u.ak.i] : u.ak.i;
-    assert( memIsValid(&aMem[u.ak.p1+u.ak.idx]) );
-    assert( memIsValid(&aMem[u.ak.p2+u.ak.idx]) );
-    REGISTER_TRACE(u.ak.p1+u.ak.idx, &aMem[u.ak.p1+u.ak.idx]);
-    REGISTER_TRACE(u.ak.p2+u.ak.idx, &aMem[u.ak.p2+u.ak.idx]);
-    assert( u.ak.i<u.ak.pKeyInfo->nField );
-    u.ak.pColl = u.ak.pKeyInfo->aColl[u.ak.i];
-    u.ak.bRev = u.ak.pKeyInfo->aSortOrder[u.ak.i];
-    iCompare = sqlite3MemCompare(&aMem[u.ak.p1+u.ak.idx], &aMem[u.ak.p2+u.ak.idx], u.ak.pColl);
+  for(u.al.i=0; u.al.i<u.al.n; u.al.i++){
+    u.al.idx = aPermute ? aPermute[u.al.i] : u.al.i;
+    assert( memIsValid(&aMem[u.al.p1+u.al.idx]) );
+    assert( memIsValid(&aMem[u.al.p2+u.al.idx]) );
+    REGISTER_TRACE(u.al.p1+u.al.idx, &aMem[u.al.p1+u.al.idx]);
+    REGISTER_TRACE(u.al.p2+u.al.idx, &aMem[u.al.p2+u.al.idx]);
+    assert( u.al.i<u.al.pKeyInfo->nField );
+    u.al.pColl = u.al.pKeyInfo->aColl[u.al.i];
+    u.al.bRev = u.al.pKeyInfo->aSortOrder[u.al.i];
+    iCompare = sqlite3MemCompare(&aMem[u.al.p1+u.al.idx], &aMem[u.al.p2+u.al.idx], u.al.pColl);
     if( iCompare ){
-      if( u.ak.bRev ) iCompare = -iCompare;
+      if( u.al.bRev ) iCompare = -iCompare;
       break;
     }
   }
@@ -67722,35 +67463,35 @@ case OP_Jump: {             /* jump */
 */
 case OP_And:              /* same as TK_AND, in1, in2, out3 */
 case OP_Or: {             /* same as TK_OR, in1, in2, out3 */
-#if 0  /* local variables moved into u.al */
+#if 0  /* local variables moved into u.am */
   int v1;    /* Left operand:  0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
   int v2;    /* Right operand: 0==FALSE, 1==TRUE, 2==UNKNOWN or NULL */
-#endif /* local variables moved into u.al */
+#endif /* local variables moved into u.am */
 
   pIn1 = &aMem[pOp->p1];
   if( pIn1->flags & MEM_Null ){
-    u.al.v1 = 2;
+    u.am.v1 = 2;
   }else{
-    u.al.v1 = sqlite3VdbeIntValue(pIn1)!=0;
+    u.am.v1 = sqlite3VdbeIntValue(pIn1)!=0;
   }
   pIn2 = &aMem[pOp->p2];
   if( pIn2->flags & MEM_Null ){
-    u.al.v2 = 2;
+    u.am.v2 = 2;
   }else{
-    u.al.v2 = sqlite3VdbeIntValue(pIn2)!=0;
+    u.am.v2 = sqlite3VdbeIntValue(pIn2)!=0;
   }
   if( pOp->opcode==OP_And ){
     static const unsigned char and_logic[] = { 0, 0, 0, 0, 1, 2, 0, 2, 2 };
-    u.al.v1 = and_logic[u.al.v1*3+u.al.v2];
+    u.am.v1 = and_logic[u.am.v1*3+u.am.v2];
   }else{
     static const unsigned char or_logic[] = { 0, 1, 2, 1, 1, 1, 2, 1, 2 };
-    u.al.v1 = or_logic[u.al.v1*3+u.al.v2];
+    u.am.v1 = or_logic[u.am.v1*3+u.am.v2];
   }
   pOut = &aMem[pOp->p3];
-  if( u.al.v1==2 ){
+  if( u.am.v1==2 ){
     MemSetTypeFlag(pOut, MEM_Null);
   }else{
-    pOut->u.i = u.al.v1;
+    pOut->u.i = u.am.v1;
     MemSetTypeFlag(pOut, MEM_Int);
   }
   break;
@@ -67794,8 +67535,6 @@ case OP_BitNot: {             /* same as TK_BITNOT, in1, out2 */
 **
 ** Check if OP_Once flag P1 is set. If so, jump to instruction P2. Otherwise,
 ** set the flag and fall through to the next instruction.
-**
-** See also: JumpOnce
 */
 case OP_Once: {             /* jump */
   assert( pOp->p1<p->nOnceFlag );
@@ -67821,21 +67560,21 @@ case OP_Once: {             /* jump */
 */
 case OP_If:                 /* jump, in1 */
 case OP_IfNot: {            /* jump, in1 */
-#if 0  /* local variables moved into u.am */
+#if 0  /* local variables moved into u.an */
   int c;
-#endif /* local variables moved into u.am */
+#endif /* local variables moved into u.an */
   pIn1 = &aMem[pOp->p1];
   if( pIn1->flags & MEM_Null ){
-    u.am.c = pOp->p3;
+    u.an.c = pOp->p3;
   }else{
 #ifdef SQLITE_OMIT_FLOATING_POINT
-    u.am.c = sqlite3VdbeIntValue(pIn1)!=0;
+    u.an.c = sqlite3VdbeIntValue(pIn1)!=0;
 #else
-    u.am.c = sqlite3VdbeRealValue(pIn1)!=0.0;
+    u.an.c = sqlite3VdbeRealValue(pIn1)!=0.0;
 #endif
-    if( pOp->opcode==OP_IfNot ) u.am.c = !u.am.c;
+    if( pOp->opcode==OP_IfNot ) u.an.c = !u.an.c;
   }
-  if( u.am.c ){
+  if( u.an.c ){
     pc = pOp->p2-1;
   }
   break;
@@ -67890,7 +67629,7 @@ case OP_NotNull: {            /* same as TK_NOTNULL, jump, in1 */
 ** skipped for length() and all content loading can be skipped for typeof().
 */
 case OP_Column: {
-#if 0  /* local variables moved into u.an */
+#if 0  /* local variables moved into u.ao */
   u32 payloadSize;   /* Number of bytes in the record */
   i64 payloadSize64; /* Number of bytes in the record */
   int p1;            /* P1 value of the opcode */
@@ -67914,126 +67653,131 @@ case OP_Column: {
   int avail;         /* Number of bytes of available data */
   u32 t;             /* A type code from the record header */
   Mem *pReg;         /* PseudoTable input register */
-#endif /* local variables moved into u.an */
+#endif /* local variables moved into u.ao */
 
 
-  u.an.p1 = pOp->p1;
-  u.an.p2 = pOp->p2;
-  u.an.pC = 0;
-  memset(&u.an.sMem, 0, sizeof(u.an.sMem));
-  assert( u.an.p1<p->nCursor );
+  u.ao.p1 = pOp->p1;
+  u.ao.p2 = pOp->p2;
+  u.ao.pC = 0;
+  memset(&u.ao.sMem, 0, sizeof(u.ao.sMem));
+  assert( u.ao.p1<p->nCursor );
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  u.an.pDest = &aMem[pOp->p3];
-  memAboutToChange(p, u.an.pDest);
-  u.an.zRec = 0;
+  u.ao.pDest = &aMem[pOp->p3];
+  memAboutToChange(p, u.ao.pDest);
+  u.ao.zRec = 0;
 
-  /* This block sets the variable u.an.payloadSize to be the total number of
+  /* This block sets the variable u.ao.payloadSize to be the total number of
   ** bytes in the record.
   **
-  ** u.an.zRec is set to be the complete text of the record if it is available.
+  ** u.ao.zRec is set to be the complete text of the record if it is available.
   ** The complete record text is always available for pseudo-tables
   ** If the record is stored in a cursor, the complete record text
-  ** might be available in the  u.an.pC->aRow cache.  Or it might not be.
-  ** If the data is unavailable,  u.an.zRec is set to NULL.
+  ** might be available in the  u.ao.pC->aRow cache.  Or it might not be.
+  ** If the data is unavailable,  u.ao.zRec is set to NULL.
   **
   ** We also compute the number of columns in the record.  For cursors,
   ** the number of columns is stored in the VdbeCursor.nField element.
   */
-  u.an.pC = p->apCsr[u.an.p1];
-  assert( u.an.pC!=0 );
+  u.ao.pC = p->apCsr[u.ao.p1];
+  assert( u.ao.pC!=0 );
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  assert( u.an.pC->pVtabCursor==0 );
+  assert( u.ao.pC->pVtabCursor==0 );
 #endif
-  u.an.pCrsr = u.an.pC->pCursor;
-  if( u.an.pCrsr!=0 ){
+  u.ao.pCrsr = u.ao.pC->pCursor;
+  if( u.ao.pCrsr!=0 ){
     /* The record is stored in a B-Tree */
-    rc = sqlite3VdbeCursorMoveto(u.an.pC);
+    rc = sqlite3VdbeCursorMoveto(u.ao.pC);
     if( rc ) goto abort_due_to_error;
-    if( u.an.pC->nullRow ){
-      u.an.payloadSize = 0;
-    }else if( u.an.pC->cacheStatus==p->cacheCtr ){
-      u.an.payloadSize = u.an.pC->payloadSize;
-      u.an.zRec = (char*)u.an.pC->aRow;
-    }else if( u.an.pC->isIndex ){
-      assert( sqlite3BtreeCursorIsValid(u.an.pCrsr) );
-      VVA_ONLY(rc =) sqlite3BtreeKeySize(u.an.pCrsr, &u.an.payloadSize64);
+    if( u.ao.pC->nullRow ){
+      u.ao.payloadSize = 0;
+    }else if( u.ao.pC->cacheStatus==p->cacheCtr ){
+      u.ao.payloadSize = u.ao.pC->payloadSize;
+      u.ao.zRec = (char*)u.ao.pC->aRow;
+    }else if( u.ao.pC->isIndex ){
+      assert( sqlite3BtreeCursorIsValid(u.ao.pCrsr) );
+      VVA_ONLY(rc =) sqlite3BtreeKeySize(u.ao.pCrsr, &u.ao.payloadSize64);
       assert( rc==SQLITE_OK );   /* True because of CursorMoveto() call above */
       /* sqlite3BtreeParseCellPtr() uses getVarint32() to extract the
-      ** payload size, so it is impossible for u.an.payloadSize64 to be
+      ** payload size, so it is impossible for u.ao.payloadSize64 to be
       ** larger than 32 bits. */
-      assert( (u.an.payloadSize64 & SQLITE_MAX_U32)==(u64)u.an.payloadSize64 );
-      u.an.payloadSize = (u32)u.an.payloadSize64;
+      assert( (u.ao.payloadSize64 & SQLITE_MAX_U32)==(u64)u.ao.payloadSize64 );
+      u.ao.payloadSize = (u32)u.ao.payloadSize64;
     }else{
-      assert( sqlite3BtreeCursorIsValid(u.an.pCrsr) );
-      VVA_ONLY(rc =) sqlite3BtreeDataSize(u.an.pCrsr, &u.an.payloadSize);
+      assert( sqlite3BtreeCursorIsValid(u.ao.pCrsr) );
+      VVA_ONLY(rc =) sqlite3BtreeDataSize(u.ao.pCrsr, &u.ao.payloadSize);
       assert( rc==SQLITE_OK );   /* DataSize() cannot fail */
     }
-  }else if( ALWAYS(u.an.pC->pseudoTableReg>0) ){
-    u.an.pReg = &aMem[u.an.pC->pseudoTableReg];
-    assert( u.an.pReg->flags & MEM_Blob );
-    assert( memIsValid(u.an.pReg) );
-    u.an.payloadSize = u.an.pReg->n;
-    u.an.zRec = u.an.pReg->z;
-    u.an.pC->cacheStatus = (pOp->p5&OPFLAG_CLEARCACHE) ? CACHE_STALE : p->cacheCtr;
-    assert( u.an.payloadSize==0 || u.an.zRec!=0 );
+  }else if( ALWAYS(u.ao.pC->pseudoTableReg>0) ){
+    u.ao.pReg = &aMem[u.ao.pC->pseudoTableReg];
+    if( u.ao.pC->multiPseudo ){
+      sqlite3VdbeMemShallowCopy(u.ao.pDest, u.ao.pReg+u.ao.p2, MEM_Ephem);
+      Deephemeralize(u.ao.pDest);
+      goto op_column_out;
+    }
+    assert( u.ao.pReg->flags & MEM_Blob );
+    assert( memIsValid(u.ao.pReg) );
+    u.ao.payloadSize = u.ao.pReg->n;
+    u.ao.zRec = u.ao.pReg->z;
+    u.ao.pC->cacheStatus = (pOp->p5&OPFLAG_CLEARCACHE) ? CACHE_STALE : p->cacheCtr;
+    assert( u.ao.payloadSize==0 || u.ao.zRec!=0 );
   }else{
     /* Consider the row to be NULL */
-    u.an.payloadSize = 0;
+    u.ao.payloadSize = 0;
   }
 
-  /* If u.an.payloadSize is 0, then just store a NULL.  This can happen because of
+  /* If u.ao.payloadSize is 0, then just store a NULL.  This can happen because of
   ** nullRow or because of a corrupt database. */
-  if( u.an.payloadSize==0 ){
-    MemSetTypeFlag(u.an.pDest, MEM_Null);
+  if( u.ao.payloadSize==0 ){
+    MemSetTypeFlag(u.ao.pDest, MEM_Null);
     goto op_column_out;
   }
   assert( db->aLimit[SQLITE_LIMIT_LENGTH]>=0 );
-  if( u.an.payloadSize > (u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
+  if( u.ao.payloadSize > (u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
     goto too_big;
   }
 
-  u.an.nField = u.an.pC->nField;
-  assert( u.an.p2<u.an.nField );
+  u.ao.nField = u.ao.pC->nField;
+  assert( u.ao.p2<u.ao.nField );
 
   /* Read and parse the table header.  Store the results of the parse
   ** into the record header cache fields of the cursor.
   */
-  u.an.aType = u.an.pC->aType;
-  if( u.an.pC->cacheStatus==p->cacheCtr ){
-    u.an.aOffset = u.an.pC->aOffset;
+  u.ao.aType = u.ao.pC->aType;
+  if( u.ao.pC->cacheStatus==p->cacheCtr ){
+    u.ao.aOffset = u.ao.pC->aOffset;
   }else{
-    assert(u.an.aType);
-    u.an.avail = 0;
-    u.an.pC->aOffset = u.an.aOffset = &u.an.aType[u.an.nField];
-    u.an.pC->payloadSize = u.an.payloadSize;
-    u.an.pC->cacheStatus = p->cacheCtr;
+    assert(u.ao.aType);
+    u.ao.avail = 0;
+    u.ao.pC->aOffset = u.ao.aOffset = &u.ao.aType[u.ao.nField];
+    u.ao.pC->payloadSize = u.ao.payloadSize;
+    u.ao.pC->cacheStatus = p->cacheCtr;
 
     /* Figure out how many bytes are in the header */
-    if( u.an.zRec ){
-      u.an.zData = u.an.zRec;
+    if( u.ao.zRec ){
+      u.ao.zData = u.ao.zRec;
     }else{
-      if( u.an.pC->isIndex ){
-        u.an.zData = (char*)sqlite3BtreeKeyFetch(u.an.pCrsr, &u.an.avail);
+      if( u.ao.pC->isIndex ){
+        u.ao.zData = (char*)sqlite3BtreeKeyFetch(u.ao.pCrsr, &u.ao.avail);
       }else{
-        u.an.zData = (char*)sqlite3BtreeDataFetch(u.an.pCrsr, &u.an.avail);
+        u.ao.zData = (char*)sqlite3BtreeDataFetch(u.ao.pCrsr, &u.ao.avail);
       }
       /* If KeyFetch()/DataFetch() managed to get the entire payload,
-      ** save the payload in the u.an.pC->aRow cache.  That will save us from
+      ** save the payload in the u.ao.pC->aRow cache.  That will save us from
       ** having to make additional calls to fetch the content portion of
       ** the record.
       */
-      assert( u.an.avail>=0 );
-      if( u.an.payloadSize <= (u32)u.an.avail ){
-        u.an.zRec = u.an.zData;
-        u.an.pC->aRow = (u8*)u.an.zData;
+      assert( u.ao.avail>=0 );
+      if( u.ao.payloadSize <= (u32)u.ao.avail ){
+        u.ao.zRec = u.ao.zData;
+        u.ao.pC->aRow = (u8*)u.ao.zData;
       }else{
-        u.an.pC->aRow = 0;
+        u.ao.pC->aRow = 0;
       }
     }
     /* The following assert is true in all cases except when
     ** the database file has been corrupted externally.
-    **    assert( u.an.zRec!=0 || u.an.avail>=u.an.payloadSize || u.an.avail>=9 ); */
-    u.an.szHdr = getVarint32((u8*)u.an.zData, u.an.offset);
+    **    assert( u.ao.zRec!=0 || u.ao.avail>=u.ao.payloadSize || u.ao.avail>=9 ); */
+    u.ao.szHdr = getVarint32((u8*)u.ao.zData, u.ao.offset);
 
     /* Make sure a corrupt database has not given us an oversize header.
     ** Do this now to avoid an oversize memory allocation.
@@ -68044,26 +67788,26 @@ case OP_Column: {
     ** 3-byte type for each of the maximum of 32768 columns plus three
     ** extra bytes for the header length itself.  32768*3 + 3 = 98307.
     */
-    if( u.an.offset > 98307 ){
+    if( u.ao.offset > 98307 ){
       rc = SQLITE_CORRUPT_BKPT;
       goto op_column_out;
     }
 
-    /* Compute in u.an.len the number of bytes of data we need to read in order
-    ** to get u.an.nField type values.  u.an.offset is an upper bound on this.  But
-    ** u.an.nField might be significantly less than the true number of columns
-    ** in the table, and in that case, 5*u.an.nField+3 might be smaller than u.an.offset.
-    ** We want to minimize u.an.len in order to limit the size of the memory
-    ** allocation, especially if a corrupt database file has caused u.an.offset
+    /* Compute in u.ao.len the number of bytes of data we need to read in order
+    ** to get u.ao.nField type values.  u.ao.offset is an upper bound on this.  But
+    ** u.ao.nField might be significantly less than the true number of columns
+    ** in the table, and in that case, 5*u.ao.nField+3 might be smaller than u.ao.offset.
+    ** We want to minimize u.ao.len in order to limit the size of the memory
+    ** allocation, especially if a corrupt database file has caused u.ao.offset
     ** to be oversized. Offset is limited to 98307 above.  But 98307 might
     ** still exceed Robson memory allocation limits on some configurations.
-    ** On systems that cannot tolerate large memory allocations, u.an.nField*5+3
-    ** will likely be much smaller since u.an.nField will likely be less than
+    ** On systems that cannot tolerate large memory allocations, u.ao.nField*5+3
+    ** will likely be much smaller since u.ao.nField will likely be less than
     ** 20 or so.  This insures that Robson memory allocation limits are
     ** not exceeded even for corrupt database files.
     */
-    u.an.len = u.an.nField*5 + 3;
-    if( u.an.len > (int)u.an.offset ) u.an.len = (int)u.an.offset;
+    u.ao.len = u.ao.nField*5 + 3;
+    if( u.ao.len > (int)u.ao.offset ) u.ao.len = (int)u.ao.offset;
 
     /* The KeyFetch() or DataFetch() above are fast and will get the entire
     ** record header in most cases.  But they will fail to get the complete
@@ -68071,51 +67815,51 @@ case OP_Column: {
     ** in the B-Tree.  When that happens, use sqlite3VdbeMemFromBtree() to
     ** acquire the complete header text.
     */
-    if( !u.an.zRec && u.an.avail<u.an.len ){
-      u.an.sMem.flags = 0;
-      u.an.sMem.db = 0;
-      rc = sqlite3VdbeMemFromBtree(u.an.pCrsr, 0, u.an.len, u.an.pC->isIndex, &u.an.sMem);
+    if( !u.ao.zRec && u.ao.avail<u.ao.len ){
+      u.ao.sMem.flags = 0;
+      u.ao.sMem.db = 0;
+      rc = sqlite3VdbeMemFromBtree(u.ao.pCrsr, 0, u.ao.len, u.ao.pC->isIndex, &u.ao.sMem);
       if( rc!=SQLITE_OK ){
         goto op_column_out;
       }
-      u.an.zData = u.an.sMem.z;
+      u.ao.zData = u.ao.sMem.z;
     }
-    u.an.zEndHdr = (u8 *)&u.an.zData[u.an.len];
-    u.an.zIdx = (u8 *)&u.an.zData[u.an.szHdr];
+    u.ao.zEndHdr = (u8 *)&u.ao.zData[u.ao.len];
+    u.ao.zIdx = (u8 *)&u.ao.zData[u.ao.szHdr];
 
-    /* Scan the header and use it to fill in the u.an.aType[] and u.an.aOffset[]
-    ** arrays.  u.an.aType[u.an.i] will contain the type integer for the u.an.i-th
-    ** column and u.an.aOffset[u.an.i] will contain the u.an.offset from the beginning
-    ** of the record to the start of the data for the u.an.i-th column
+    /* Scan the header and use it to fill in the u.ao.aType[] and u.ao.aOffset[]
+    ** arrays.  u.ao.aType[u.ao.i] will contain the type integer for the u.ao.i-th
+    ** column and u.ao.aOffset[u.ao.i] will contain the u.ao.offset from the beginning
+    ** of the record to the start of the data for the u.ao.i-th column
     */
-    for(u.an.i=0; u.an.i<u.an.nField; u.an.i++){
-      if( u.an.zIdx<u.an.zEndHdr ){
-        u.an.aOffset[u.an.i] = u.an.offset;
-        if( u.an.zIdx[0]<0x80 ){
-          u.an.t = u.an.zIdx[0];
-          u.an.zIdx++;
+    for(u.ao.i=0; u.ao.i<u.ao.nField; u.ao.i++){
+      if( u.ao.zIdx<u.ao.zEndHdr ){
+        u.ao.aOffset[u.ao.i] = u.ao.offset;
+        if( u.ao.zIdx[0]<0x80 ){
+          u.ao.t = u.ao.zIdx[0];
+          u.ao.zIdx++;
         }else{
-          u.an.zIdx += sqlite3GetVarint32(u.an.zIdx, &u.an.t);
+          u.ao.zIdx += sqlite3GetVarint32(u.ao.zIdx, &u.ao.t);
         }
-        u.an.aType[u.an.i] = u.an.t;
-        u.an.szField = sqlite3VdbeSerialTypeLen(u.an.t);
-        u.an.offset += u.an.szField;
-        if( u.an.offset<u.an.szField ){  /* True if u.an.offset overflows */
-          u.an.zIdx = &u.an.zEndHdr[1];  /* Forces SQLITE_CORRUPT return below */
+        u.ao.aType[u.ao.i] = u.ao.t;
+        u.ao.szField = sqlite3VdbeSerialTypeLen(u.ao.t);
+        u.ao.offset += u.ao.szField;
+        if( u.ao.offset<u.ao.szField ){  /* True if u.ao.offset overflows */
+          u.ao.zIdx = &u.ao.zEndHdr[1];  /* Forces SQLITE_CORRUPT return below */
           break;
         }
       }else{
-        /* If u.an.i is less that u.an.nField, then there are fewer fields in this
+        /* If u.ao.i is less that u.ao.nField, then there are fewer fields in this
         ** record than SetNumColumns indicated there are columns in the
-        ** table. Set the u.an.offset for any extra columns not present in
+        ** table. Set the u.ao.offset for any extra columns not present in
         ** the record to 0. This tells code below to store the default value
         ** for the column instead of deserializing a value from the record.
         */
-        u.an.aOffset[u.an.i] = 0;
+        u.ao.aOffset[u.ao.i] = 0;
       }
     }
-    sqlite3VdbeMemRelease(&u.an.sMem);
-    u.an.sMem.flags = MEM_Null;
+    sqlite3VdbeMemRelease(&u.ao.sMem);
+    u.ao.sMem.flags = MEM_Null;
 
     /* If we have read more header data than was contained in the header,
     ** or if the end of the last field appears to be past the end of the
@@ -68123,78 +67867,78 @@ case OP_Column: {
     ** of the record (when all fields present), then we must be dealing
     ** with a corrupt database.
     */
-    if( (u.an.zIdx > u.an.zEndHdr) || (u.an.offset > u.an.payloadSize)
-         || (u.an.zIdx==u.an.zEndHdr && u.an.offset!=u.an.payloadSize) ){
+    if( (u.ao.zIdx > u.ao.zEndHdr) || (u.ao.offset > u.ao.payloadSize)
+         || (u.ao.zIdx==u.ao.zEndHdr && u.ao.offset!=u.ao.payloadSize) ){
       rc = SQLITE_CORRUPT_BKPT;
       goto op_column_out;
     }
   }
 
-  /* Get the column information. If u.an.aOffset[u.an.p2] is non-zero, then
-  ** deserialize the value from the record. If u.an.aOffset[u.an.p2] is zero,
+  /* Get the column information. If u.ao.aOffset[u.ao.p2] is non-zero, then
+  ** deserialize the value from the record. If u.ao.aOffset[u.ao.p2] is zero,
   ** then there are not enough fields in the record to satisfy the
   ** request.  In this case, set the value NULL or to P4 if P4 is
   ** a pointer to a Mem object.
   */
-  if( u.an.aOffset[u.an.p2] ){
+  if( u.ao.aOffset[u.ao.p2] ){
     assert( rc==SQLITE_OK );
-    if( u.an.zRec ){
+    if( u.ao.zRec ){
       /* This is the common case where the whole row fits on a single page */
-      VdbeMemRelease(u.an.pDest);
-      sqlite3VdbeSerialGet((u8 *)&u.an.zRec[u.an.aOffset[u.an.p2]], u.an.aType[u.an.p2], u.an.pDest);
+      VdbeMemRelease(u.ao.pDest);
+      sqlite3VdbeSerialGet((u8 *)&u.ao.zRec[u.ao.aOffset[u.ao.p2]], u.ao.aType[u.ao.p2], u.ao.pDest);
     }else{
       /* This branch happens only when the row overflows onto multiple pages */
-      u.an.t = u.an.aType[u.an.p2];
+      u.ao.t = u.ao.aType[u.ao.p2];
       if( (pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0
-       && ((u.an.t>=12 && (u.an.t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0)
+       && ((u.ao.t>=12 && (u.ao.t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0)
       ){
         /* Content is irrelevant for the typeof() function and for
         ** the length(X) function if X is a blob.  So we might as well use
         ** bogus content rather than reading content from disk.  NULL works
-        ** for text and blob and whatever is in the u.an.payloadSize64 variable
+        ** for text and blob and whatever is in the u.ao.payloadSize64 variable
         ** will work for everything else. */
-        u.an.zData = u.an.t<12 ? (char*)&u.an.payloadSize64 : 0;
+        u.ao.zData = u.ao.t<12 ? (char*)&u.ao.payloadSize64 : 0;
       }else{
-        u.an.len = sqlite3VdbeSerialTypeLen(u.an.t);
-        sqlite3VdbeMemMove(&u.an.sMem, u.an.pDest);
-        rc = sqlite3VdbeMemFromBtree(u.an.pCrsr, u.an.aOffset[u.an.p2], u.an.len,  u.an.pC->isIndex,
-                                     &u.an.sMem);
+        u.ao.len = sqlite3VdbeSerialTypeLen(u.ao.t);
+        sqlite3VdbeMemMove(&u.ao.sMem, u.ao.pDest);
+        rc = sqlite3VdbeMemFromBtree(u.ao.pCrsr, u.ao.aOffset[u.ao.p2], u.ao.len,  u.ao.pC->isIndex,
+                                     &u.ao.sMem);
         if( rc!=SQLITE_OK ){
           goto op_column_out;
         }
-        u.an.zData = u.an.sMem.z;
+        u.ao.zData = u.ao.sMem.z;
       }
-      sqlite3VdbeSerialGet((u8*)u.an.zData, u.an.t, u.an.pDest);
+      sqlite3VdbeSerialGet((u8*)u.ao.zData, u.ao.t, u.ao.pDest);
     }
-    u.an.pDest->enc = encoding;
+    u.ao.pDest->enc = encoding;
   }else{
     if( pOp->p4type==P4_MEM ){
-      sqlite3VdbeMemShallowCopy(u.an.pDest, pOp->p4.pMem, MEM_Static);
+      sqlite3VdbeMemShallowCopy(u.ao.pDest, pOp->p4.pMem, MEM_Static);
     }else{
-      MemSetTypeFlag(u.an.pDest, MEM_Null);
+      MemSetTypeFlag(u.ao.pDest, MEM_Null);
     }
   }
 
   /* If we dynamically allocated space to hold the data (in the
   ** sqlite3VdbeMemFromBtree() call above) then transfer control of that
-  ** dynamically allocated space over to the u.an.pDest structure.
+  ** dynamically allocated space over to the u.ao.pDest structure.
   ** This prevents a memory copy.
   */
-  if( u.an.sMem.zMalloc ){
-    assert( u.an.sMem.z==u.an.sMem.zMalloc );
-    assert( !(u.an.pDest->flags & MEM_Dyn) );
-    assert( !(u.an.pDest->flags & (MEM_Blob|MEM_Str)) || u.an.pDest->z==u.an.sMem.z );
-    u.an.pDest->flags &= ~(MEM_Ephem|MEM_Static);
-    u.an.pDest->flags |= MEM_Term;
-    u.an.pDest->z = u.an.sMem.z;
-    u.an.pDest->zMalloc = u.an.sMem.zMalloc;
+  if( u.ao.sMem.zMalloc ){
+    assert( u.ao.sMem.z==u.ao.sMem.zMalloc );
+    assert( !(u.ao.pDest->flags & MEM_Dyn) );
+    assert( !(u.ao.pDest->flags & (MEM_Blob|MEM_Str)) || u.ao.pDest->z==u.ao.sMem.z );
+    u.ao.pDest->flags &= ~(MEM_Ephem|MEM_Static);
+    u.ao.pDest->flags |= MEM_Term;
+    u.ao.pDest->z = u.ao.sMem.z;
+    u.ao.pDest->zMalloc = u.ao.sMem.zMalloc;
   }
 
-  rc = sqlite3VdbeMemMakeWriteable(u.an.pDest);
+  rc = sqlite3VdbeMemMakeWriteable(u.ao.pDest);
 
 op_column_out:
-  UPDATE_MAX_BLOBSIZE(u.an.pDest);
-  REGISTER_TRACE(pOp->p3, u.an.pDest);
+  UPDATE_MAX_BLOBSIZE(u.ao.pDest);
+  REGISTER_TRACE(pOp->p3, u.ao.pDest);
   break;
 }
 
@@ -68207,20 +67951,20 @@ op_column_out:
 ** memory cell in the range.
 */
 case OP_Affinity: {
-#if 0  /* local variables moved into u.ao */
+#if 0  /* local variables moved into u.ap */
   const char *zAffinity;   /* The affinity to be applied */
   char cAff;               /* A single character of affinity */
-#endif /* local variables moved into u.ao */
+#endif /* local variables moved into u.ap */
 
-  u.ao.zAffinity = pOp->p4.z;
-  assert( u.ao.zAffinity!=0 );
-  assert( u.ao.zAffinity[pOp->p2]==0 );
+  u.ap.zAffinity = pOp->p4.z;
+  assert( u.ap.zAffinity!=0 );
+  assert( u.ap.zAffinity[pOp->p2]==0 );
   pIn1 = &aMem[pOp->p1];
-  while( (u.ao.cAff = *(u.ao.zAffinity++))!=0 ){
+  while( (u.ap.cAff = *(u.ap.zAffinity++))!=0 ){
     assert( pIn1 <= &p->aMem[p->nMem] );
     assert( memIsValid(pIn1) );
     ExpandBlob(pIn1);
-    applyAffinity(pIn1, u.ao.cAff, encoding);
+    applyAffinity(pIn1, u.ap.cAff, encoding);
     pIn1++;
   }
   break;
@@ -68242,7 +67986,7 @@ case OP_Affinity: {
 ** If P4 is NULL then all index fields have the affinity NONE.
 */
 case OP_MakeRecord: {
-#if 0  /* local variables moved into u.ap */
+#if 0  /* local variables moved into u.aq */
   u8 *zNewRecord;        /* A buffer to hold the data for the new record */
   Mem *pRec;             /* The new record */
   u64 nData;             /* Number of bytes of data space */
@@ -68258,7 +68002,7 @@ case OP_MakeRecord: {
   int file_format;       /* File format to use for encoding */
   int i;                 /* Space used in zNewRecord[] */
   int len;               /* Length of a field */
-#endif /* local variables moved into u.ap */
+#endif /* local variables moved into u.aq */
 
   /* Assuming the record contains N fields, the record format looks
   ** like this:
@@ -68275,16 +68019,16 @@ case OP_MakeRecord: {
   ** hdr-size field is also a varint which is the offset from the beginning
   ** of the record to data0.
   */
-  u.ap.nData = 0;         /* Number of bytes of data space */
-  u.ap.nHdr = 0;          /* Number of bytes of header space */
-  u.ap.nZero = 0;         /* Number of zero bytes at the end of the record */
-  u.ap.nField = pOp->p1;
-  u.ap.zAffinity = pOp->p4.z;
-  assert( u.ap.nField>0 && pOp->p2>0 && pOp->p2+u.ap.nField<=p->nMem+1 );
-  u.ap.pData0 = &aMem[u.ap.nField];
-  u.ap.nField = pOp->p2;
-  u.ap.pLast = &u.ap.pData0[u.ap.nField-1];
-  u.ap.file_format = p->minWriteFileFormat;
+  u.aq.nData = 0;         /* Number of bytes of data space */
+  u.aq.nHdr = 0;          /* Number of bytes of header space */
+  u.aq.nZero = 0;         /* Number of zero bytes at the end of the record */
+  u.aq.nField = pOp->p1;
+  u.aq.zAffinity = pOp->p4.z;
+  assert( u.aq.nField>0 && pOp->p2>0 && pOp->p2+u.aq.nField<=p->nMem+1 );
+  u.aq.pData0 = &aMem[u.aq.nField];
+  u.aq.nField = pOp->p2;
+  u.aq.pLast = &u.aq.pData0[u.aq.nField-1];
+  u.aq.file_format = p->minWriteFileFormat;
 
   /* Identify the output register */
   assert( pOp->p3<pOp->p1 || pOp->p3>=pOp->p1+pOp->p2 );
@@ -68294,34 +68038,34 @@ case OP_MakeRecord: {
   /* Loop through the elements that will make up the record to figure
   ** out how much space is required for the new record.
   */
-  for(u.ap.pRec=u.ap.pData0; u.ap.pRec<=u.ap.pLast; u.ap.pRec++){
-    assert( memIsValid(u.ap.pRec) );
-    if( u.ap.zAffinity ){
-      applyAffinity(u.ap.pRec, u.ap.zAffinity[u.ap.pRec-u.ap.pData0], encoding);
+  for(u.aq.pRec=u.aq.pData0; u.aq.pRec<=u.aq.pLast; u.aq.pRec++){
+    assert( memIsValid(u.aq.pRec) );
+    if( u.aq.zAffinity ){
+      applyAffinity(u.aq.pRec, u.aq.zAffinity[u.aq.pRec-u.aq.pData0], encoding);
     }
-    if( u.ap.pRec->flags&MEM_Zero && u.ap.pRec->n>0 ){
-      sqlite3VdbeMemExpandBlob(u.ap.pRec);
+    if( u.aq.pRec->flags&MEM_Zero && u.aq.pRec->n>0 ){
+      sqlite3VdbeMemExpandBlob(u.aq.pRec);
     }
-    u.ap.serial_type = sqlite3VdbeSerialType(u.ap.pRec, u.ap.file_format);
-    u.ap.len = sqlite3VdbeSerialTypeLen(u.ap.serial_type);
-    u.ap.nData += u.ap.len;
-    u.ap.nHdr += sqlite3VarintLen(u.ap.serial_type);
-    if( u.ap.pRec->flags & MEM_Zero ){
+    u.aq.serial_type = sqlite3VdbeSerialType(u.aq.pRec, u.aq.file_format);
+    u.aq.len = sqlite3VdbeSerialTypeLen(u.aq.serial_type);
+    u.aq.nData += u.aq.len;
+    u.aq.nHdr += sqlite3VarintLen(u.aq.serial_type);
+    if( u.aq.pRec->flags & MEM_Zero ){
       /* Only pure zero-filled BLOBs can be input to this Opcode.
       ** We do not allow blobs with a prefix and a zero-filled tail. */
-      u.ap.nZero += u.ap.pRec->u.nZero;
-    }else if( u.ap.len ){
-      u.ap.nZero = 0;
+      u.aq.nZero += u.aq.pRec->u.nZero;
+    }else if( u.aq.len ){
+      u.aq.nZero = 0;
     }
   }
 
   /* Add the initial header varint and total the size */
-  u.ap.nHdr += u.ap.nVarint = sqlite3VarintLen(u.ap.nHdr);
-  if( u.ap.nVarint<sqlite3VarintLen(u.ap.nHdr) ){
-    u.ap.nHdr++;
+  u.aq.nHdr += u.aq.nVarint = sqlite3VarintLen(u.aq.nHdr);
+  if( u.aq.nVarint<sqlite3VarintLen(u.aq.nHdr) ){
+    u.aq.nHdr++;
   }
-  u.ap.nByte = u.ap.nHdr+u.ap.nData-u.ap.nZero;
-  if( u.ap.nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+  u.aq.nByte = u.aq.nHdr+u.aq.nData-u.aq.nZero;
+  if( u.aq.nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
     goto too_big;
   }
 
@@ -68330,28 +68074,28 @@ case OP_MakeRecord: {
   ** be one of the input registers (because the following call to
   ** sqlite3VdbeMemGrow() could clobber the value before it is used).
   */
-  if( sqlite3VdbeMemGrow(pOut, (int)u.ap.nByte, 0) ){
+  if( sqlite3VdbeMemGrow(pOut, (int)u.aq.nByte, 0) ){
     goto no_mem;
   }
-  u.ap.zNewRecord = (u8 *)pOut->z;
+  u.aq.zNewRecord = (u8 *)pOut->z;
 
   /* Write the record */
-  u.ap.i = putVarint32(u.ap.zNewRecord, u.ap.nHdr);
-  for(u.ap.pRec=u.ap.pData0; u.ap.pRec<=u.ap.pLast; u.ap.pRec++){
-    u.ap.serial_type = sqlite3VdbeSerialType(u.ap.pRec, u.ap.file_format);
-    u.ap.i += putVarint32(&u.ap.zNewRecord[u.ap.i], u.ap.serial_type);      /* serial type */
+  u.aq.i = putVarint32(u.aq.zNewRecord, u.aq.nHdr);
+  for(u.aq.pRec=u.aq.pData0; u.aq.pRec<=u.aq.pLast; u.aq.pRec++){
+    u.aq.serial_type = sqlite3VdbeSerialType(u.aq.pRec, u.aq.file_format);
+    u.aq.i += putVarint32(&u.aq.zNewRecord[u.aq.i], u.aq.serial_type);      /* serial type */
   }
-  for(u.ap.pRec=u.ap.pData0; u.ap.pRec<=u.ap.pLast; u.ap.pRec++){  /* serial data */
-    u.ap.i += sqlite3VdbeSerialPut(&u.ap.zNewRecord[u.ap.i], (int)(u.ap.nByte-u.ap.i), u.ap.pRec,u.ap.file_format);
+  for(u.aq.pRec=u.aq.pData0; u.aq.pRec<=u.aq.pLast; u.aq.pRec++){  /* serial data */
+    u.aq.i += sqlite3VdbeSerialPut(&u.aq.zNewRecord[u.aq.i], (int)(u.aq.nByte-u.aq.i), u.aq.pRec,u.aq.file_format);
   }
-  assert( u.ap.i==u.ap.nByte );
+  assert( u.aq.i==u.aq.nByte );
 
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  pOut->n = (int)u.ap.nByte;
+  pOut->n = (int)u.aq.nByte;
   pOut->flags = MEM_Blob | MEM_Dyn;
   pOut->xDel = 0;
-  if( u.ap.nZero ){
-    pOut->u.nZero = u.ap.nZero;
+  if( u.aq.nZero ){
+    pOut->u.nZero = u.aq.nZero;
     pOut->flags |= MEM_Zero;
   }
   pOut->enc = SQLITE_UTF8;  /* In case the blob is ever converted to text */
@@ -68367,18 +68111,18 @@ case OP_MakeRecord: {
 */
 #ifndef SQLITE_OMIT_BTREECOUNT
 case OP_Count: {         /* out2-prerelease */
-#if 0  /* local variables moved into u.aq */
+#if 0  /* local variables moved into u.ar */
   i64 nEntry;
   BtCursor *pCrsr;
-#endif /* local variables moved into u.aq */
+#endif /* local variables moved into u.ar */
 
-  u.aq.pCrsr = p->apCsr[pOp->p1]->pCursor;
-  if( ALWAYS(u.aq.pCrsr) ){
-    rc = sqlite3BtreeCount(u.aq.pCrsr, &u.aq.nEntry);
+  u.ar.pCrsr = p->apCsr[pOp->p1]->pCursor;
+  if( ALWAYS(u.ar.pCrsr) ){
+    rc = sqlite3BtreeCount(u.ar.pCrsr, &u.ar.nEntry);
   }else{
-    u.aq.nEntry = 0;
+    u.ar.nEntry = 0;
   }
-  pOut->u.i = u.aq.nEntry;
+  pOut->u.i = u.ar.nEntry;
   break;
 }
 #endif
@@ -68390,7 +68134,7 @@ case OP_Count: {         /* out2-prerelease */
 ** existing savepoint, P1==1, or to rollback an existing savepoint P1==2.
 */
 case OP_Savepoint: {
-#if 0  /* local variables moved into u.ar */
+#if 0  /* local variables moved into u.as */
   int p1;                         /* Value of P1 operand */
   char *zName;                    /* Name of savepoint */
   int nName;
@@ -68399,21 +68143,22 @@ case OP_Savepoint: {
   Savepoint *pTmp;
   int iSavepoint;
   int ii;
-#endif /* local variables moved into u.ar */
+#endif /* local variables moved into u.as */
 
-  u.ar.p1 = pOp->p1;
-  u.ar.zName = pOp->p4.z;
+  u.as.p1 = pOp->p1;
+  u.as.zName = pOp->p4.z;
 
-  /* Assert that the u.ar.p1 parameter is valid. Also that if there is no open
+  /* Assert that the u.as.p1 parameter is valid. Also that if there is no open
   ** transaction, then there cannot be any savepoints.
   */
   assert( db->pSavepoint==0 || db->autoCommit==0 );
-  assert( u.ar.p1==SAVEPOINT_BEGIN||u.ar.p1==SAVEPOINT_RELEASE||u.ar.p1==SAVEPOINT_ROLLBACK );
+  assert( u.as.p1==SAVEPOINT_BEGIN||u.as.p1==SAVEPOINT_RELEASE||u.as.p1==SAVEPOINT_ROLLBACK );
   assert( db->pSavepoint || db->isTransactionSavepoint==0 );
   assert( checkSavepointCount(db) );
+  assert( p->bIsReader );
 
-  if( u.ar.p1==SAVEPOINT_BEGIN ){
-    if( db->writeVdbeCnt>0 ){
+  if( u.as.p1==SAVEPOINT_BEGIN ){
+    if( db->nVdbeWrite>0 ){
       /* A new savepoint cannot be created if there are active write
       ** statements (i.e. open read/write incremental blob handles).
       */
@@ -68421,7 +68166,7 @@ case OP_Savepoint: {
         "SQL statements in progress");
       rc = SQLITE_BUSY;
     }else{
-      u.ar.nName = sqlite3Strlen30(u.ar.zName);
+      u.as.nName = sqlite3Strlen30(u.as.zName);
 
 #ifndef SQLITE_OMIT_VIRTUALTABLE
       /* This call is Ok even if this savepoint is actually a transaction
@@ -68435,10 +68180,10 @@ case OP_Savepoint: {
 #endif
 
       /* Create a new savepoint structure. */
-      u.ar.pNew = sqlite3DbMallocRaw(db, sizeof(Savepoint)+u.ar.nName+1);
-      if( u.ar.pNew ){
-        u.ar.pNew->zName = (char *)&u.ar.pNew[1];
-        memcpy(u.ar.pNew->zName, u.ar.zName, u.ar.nName+1);
+      u.as.pNew = sqlite3DbMallocRaw(db, sizeof(Savepoint)+u.as.nName+1);
+      if( u.as.pNew ){
+        u.as.pNew->zName = (char *)&u.as.pNew[1];
+        memcpy(u.as.pNew->zName, u.as.zName, u.as.nName+1);
 
         /* If there is no open transaction, then mark this as a special
         ** "transaction savepoint". */
@@ -68450,27 +68195,28 @@ case OP_Savepoint: {
         }
 
         /* Link the new savepoint into the database handle's list. */
-        u.ar.pNew->pNext = db->pSavepoint;
-        db->pSavepoint = u.ar.pNew;
-        u.ar.pNew->nDeferredCons = db->nDeferredCons;
+        u.as.pNew->pNext = db->pSavepoint;
+        db->pSavepoint = u.as.pNew;
+        u.as.pNew->nDeferredCons = db->nDeferredCons;
+        u.as.pNew->nDeferredImmCons = db->nDeferredImmCons;
       }
     }
   }else{
-    u.ar.iSavepoint = 0;
+    u.as.iSavepoint = 0;
 
     /* Find the named savepoint. If there is no such savepoint, then an
     ** an error is returned to the user.  */
     for(
-      u.ar.pSavepoint = db->pSavepoint;
-      u.ar.pSavepoint && sqlite3StrICmp(u.ar.pSavepoint->zName, u.ar.zName);
-      u.ar.pSavepoint = u.ar.pSavepoint->pNext
+      u.as.pSavepoint = db->pSavepoint;
+      u.as.pSavepoint && sqlite3StrICmp(u.as.pSavepoint->zName, u.as.zName);
+      u.as.pSavepoint = u.as.pSavepoint->pNext
     ){
-      u.ar.iSavepoint++;
+      u.as.iSavepoint++;
     }
-    if( !u.ar.pSavepoint ){
-      sqlite3SetString(&p->zErrMsg, db, "no such savepoint: %s", u.ar.zName);
+    if( !u.as.pSavepoint ){
+      sqlite3SetString(&p->zErrMsg, db, "no such savepoint: %s", u.as.zName);
       rc = SQLITE_ERROR;
-    }else if( db->writeVdbeCnt>0 && u.ar.p1==SAVEPOINT_RELEASE ){
+    }else if( db->nVdbeWrite>0 && u.as.p1==SAVEPOINT_RELEASE ){
       /* It is not possible to release (commit) a savepoint if there are
       ** active write statements.
       */
@@ -68484,8 +68230,8 @@ case OP_Savepoint: {
       ** and this is a RELEASE command, then the current transaction
       ** is committed.
       */
-      int isTransaction = u.ar.pSavepoint->pNext==0 && db->isTransactionSavepoint;
-      if( isTransaction && u.ar.p1==SAVEPOINT_RELEASE ){
+      int isTransaction = u.as.pSavepoint->pNext==0 && db->isTransactionSavepoint;
+      if( isTransaction && u.as.p1==SAVEPOINT_RELEASE ){
         if( (rc = sqlite3VdbeCheckFk(p, 1))!=SQLITE_OK ){
           goto vdbe_return;
         }
@@ -68499,19 +68245,19 @@ case OP_Savepoint: {
         db->isTransactionSavepoint = 0;
         rc = p->rc;
       }else{
-        u.ar.iSavepoint = db->nSavepoint - u.ar.iSavepoint - 1;
-        if( u.ar.p1==SAVEPOINT_ROLLBACK ){
-          for(u.ar.ii=0; u.ar.ii<db->nDb; u.ar.ii++){
-            sqlite3BtreeTripAllCursors(db->aDb[u.ar.ii].pBt, SQLITE_ABORT);
+        u.as.iSavepoint = db->nSavepoint - u.as.iSavepoint - 1;
+        if( u.as.p1==SAVEPOINT_ROLLBACK ){
+          for(u.as.ii=0; u.as.ii<db->nDb; u.as.ii++){
+            sqlite3BtreeTripAllCursors(db->aDb[u.as.ii].pBt, SQLITE_ABORT);
           }
         }
-        for(u.ar.ii=0; u.ar.ii<db->nDb; u.ar.ii++){
-          rc = sqlite3BtreeSavepoint(db->aDb[u.ar.ii].pBt, u.ar.p1, u.ar.iSavepoint);
+        for(u.as.ii=0; u.as.ii<db->nDb; u.as.ii++){
+          rc = sqlite3BtreeSavepoint(db->aDb[u.as.ii].pBt, u.as.p1, u.as.iSavepoint);
           if( rc!=SQLITE_OK ){
             goto abort_due_to_error;
           }
         }
-        if( u.ar.p1==SAVEPOINT_ROLLBACK && (db->flags&SQLITE_InternChanges)!=0 ){
+        if( u.as.p1==SAVEPOINT_ROLLBACK && (db->flags&SQLITE_InternChanges)!=0 ){
           sqlite3ExpirePreparedStatements(db);
           sqlite3ResetAllSchemasOfConnection(db);
           db->flags = (db->flags | SQLITE_InternChanges);
@@ -68520,10 +68266,10 @@ case OP_Savepoint: {
 
       /* Regardless of whether this is a RELEASE or ROLLBACK, destroy all
       ** savepoints nested inside of the savepoint being operated on. */
-      while( db->pSavepoint!=u.ar.pSavepoint ){
-        u.ar.pTmp = db->pSavepoint;
-        db->pSavepoint = u.ar.pTmp->pNext;
-        sqlite3DbFree(db, u.ar.pTmp);
+      while( db->pSavepoint!=u.as.pSavepoint ){
+        u.as.pTmp = db->pSavepoint;
+        db->pSavepoint = u.as.pTmp->pNext;
+        sqlite3DbFree(db, u.as.pTmp);
         db->nSavepoint--;
       }
 
@@ -68531,19 +68277,20 @@ case OP_Savepoint: {
       ** too. If it is a ROLLBACK TO, then set the number of deferred
       ** constraint violations present in the database to the value stored
       ** when the savepoint was created.  */
-      if( u.ar.p1==SAVEPOINT_RELEASE ){
-        assert( u.ar.pSavepoint==db->pSavepoint );
-        db->pSavepoint = u.ar.pSavepoint->pNext;
-        sqlite3DbFree(db, u.ar.pSavepoint);
+      if( u.as.p1==SAVEPOINT_RELEASE ){
+        assert( u.as.pSavepoint==db->pSavepoint );
+        db->pSavepoint = u.as.pSavepoint->pNext;
+        sqlite3DbFree(db, u.as.pSavepoint);
         if( !isTransaction ){
           db->nSavepoint--;
         }
       }else{
-        db->nDeferredCons = u.ar.pSavepoint->nDeferredCons;
+        db->nDeferredCons = u.as.pSavepoint->nDeferredCons;
+        db->nDeferredImmCons = u.as.pSavepoint->nDeferredImmCons;
       }
 
       if( !isTransaction ){
-        rc = sqlite3VtabSavepoint(db, u.ar.p1, u.ar.iSavepoint);
+        rc = sqlite3VtabSavepoint(db, u.as.p1, u.as.iSavepoint);
         if( rc!=SQLITE_OK ) goto abort_due_to_error;
       }
     }
@@ -68562,21 +68309,22 @@ case OP_Savepoint: {
 ** This instruction causes the VM to halt.
 */
 case OP_AutoCommit: {
-#if 0  /* local variables moved into u.as */
+#if 0  /* local variables moved into u.at */
   int desiredAutoCommit;
   int iRollback;
   int turnOnAC;
-#endif /* local variables moved into u.as */
+#endif /* local variables moved into u.at */
 
-  u.as.desiredAutoCommit = pOp->p1;
-  u.as.iRollback = pOp->p2;
-  u.as.turnOnAC = u.as.desiredAutoCommit && !db->autoCommit;
-  assert( u.as.desiredAutoCommit==1 || u.as.desiredAutoCommit==0 );
-  assert( u.as.desiredAutoCommit==1 || u.as.iRollback==0 );
-  assert( db->activeVdbeCnt>0 );  /* At least this one VM is active */
+  u.at.desiredAutoCommit = pOp->p1;
+  u.at.iRollback = pOp->p2;
+  u.at.turnOnAC = u.at.desiredAutoCommit && !db->autoCommit;
+  assert( u.at.desiredAutoCommit==1 || u.at.desiredAutoCommit==0 );
+  assert( u.at.desiredAutoCommit==1 || u.at.iRollback==0 );
+  assert( db->nVdbeActive>0 );  /* At least this one VM is active */
+  assert( p->bIsReader );
 
 #if 0
-  if( u.as.turnOnAC && u.as.iRollback && db->activeVdbeCnt>1 ){
+  if( u.at.turnOnAC && u.at.iRollback && db->nVdbeActive>1 ){
     /* If this instruction implements a ROLLBACK and other VMs are
     ** still running, and a transaction is active, return an error indicating
     ** that the other VMs must complete first.
@@ -68586,25 +68334,25 @@ case OP_AutoCommit: {
     rc = SQLITE_BUSY;
   }else
 #endif
-  if( u.as.turnOnAC && !u.as.iRollback && db->writeVdbeCnt>0 ){
+  if( u.at.turnOnAC && !u.at.iRollback && db->nVdbeWrite>0 ){
     /* If this instruction implements a COMMIT and other VMs are writing
     ** return an error indicating that the other VMs must complete first.
     */
     sqlite3SetString(&p->zErrMsg, db, "cannot commit transaction - "
         "SQL statements in progress");
     rc = SQLITE_BUSY;
-  }else if( u.as.desiredAutoCommit!=db->autoCommit ){
-    if( u.as.iRollback ){
-      assert( u.as.desiredAutoCommit==1 );
+  }else if( u.at.desiredAutoCommit!=db->autoCommit ){
+    if( u.at.iRollback ){
+      assert( u.at.desiredAutoCommit==1 );
       sqlite3RollbackAll(db, SQLITE_ABORT_ROLLBACK);
       db->autoCommit = 1;
     }else if( (rc = sqlite3VdbeCheckFk(p, 1))!=SQLITE_OK ){
       goto vdbe_return;
     }else{
-      db->autoCommit = (u8)u.as.desiredAutoCommit;
+      db->autoCommit = (u8)u.at.desiredAutoCommit;
       if( sqlite3VdbeHalt(p)==SQLITE_BUSY ){
         p->pc = pc;
-        db->autoCommit = (u8)(1-u.as.desiredAutoCommit);
+        db->autoCommit = (u8)(1-u.at.desiredAutoCommit);
         p->rc = rc = SQLITE_BUSY;
         goto vdbe_return;
       }
@@ -68619,8 +68367,8 @@ case OP_AutoCommit: {
     goto vdbe_return;
   }else{
     sqlite3SetString(&p->zErrMsg, db,
-        (!u.as.desiredAutoCommit)?"cannot start a transaction within a transaction":(
-        (u.as.iRollback)?"cannot rollback - no transaction is active":
+        (!u.at.desiredAutoCommit)?"cannot start a transaction within a transaction":(
+        (u.at.iRollback)?"cannot rollback - no transaction is active":
                    "cannot commit - no transaction is active"));
 
     rc = SQLITE_ERROR;
@@ -68644,8 +68392,8 @@ case OP_AutoCommit: {
 ** other process can start another write transaction while this transaction is
 ** underway.  Starting a write transaction also creates a rollback journal. A
 ** write transaction must be started before any changes can be made to the
-** database.  If P2 is 2 or greater then an EXCLUSIVE lock is also obtained
-** on the file.
+** database.  If P2 is greater than or equal to 2 then an EXCLUSIVE lock is
+** also obtained on the file.
 **
 ** If a write-transaction is started and the Vdbe.usesStmtJournal flag is
 ** true (this flag is set if the Vdbe may modify more than one row and may
@@ -68660,16 +68408,22 @@ case OP_AutoCommit: {
 ** If P2 is zero, then a read-lock is obtained on the database file.
 */
 case OP_Transaction: {
-#if 0  /* local variables moved into u.at */
+#if 0  /* local variables moved into u.au */
   Btree *pBt;
-#endif /* local variables moved into u.at */
+#endif /* local variables moved into u.au */
 
+  assert( p->bIsReader );
+  assert( p->readOnly==0 || pOp->p2==0 );
   assert( pOp->p1>=0 && pOp->p1<db->nDb );
   assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
-  u.at.pBt = db->aDb[pOp->p1].pBt;
+  if( pOp->p2 && (db->flags & SQLITE_QueryOnly)!=0 ){
+    rc = SQLITE_READONLY;
+    goto abort_due_to_error;
+  }
+  u.au.pBt = db->aDb[pOp->p1].pBt;
 
-  if( u.at.pBt ){
-    rc = sqlite3BtreeBeginTrans(u.at.pBt, pOp->p2);
+  if( u.au.pBt ){
+    rc = sqlite3BtreeBeginTrans(u.au.pBt, pOp->p2);
     if( rc==SQLITE_BUSY ){
       p->pc = pc;
       p->rc = rc = SQLITE_BUSY;
@@ -68680,9 +68434,9 @@ case OP_Transaction: {
     }
 
     if( pOp->p2 && p->usesStmtJournal
-     && (db->autoCommit==0 || db->activeVdbeCnt>1)
+     && (db->autoCommit==0 || db->nVdbeRead>1)
     ){
-      assert( sqlite3BtreeIsInTrans(u.at.pBt) );
+      assert( sqlite3BtreeIsInTrans(u.au.pBt) );
       if( p->iStatement==0 ){
         assert( db->nStatement>=0 && db->nSavepoint>=0 );
         db->nStatement++;
@@ -68691,13 +68445,14 @@ case OP_Transaction: {
 
       rc = sqlite3VtabSavepoint(db, SAVEPOINT_BEGIN, p->iStatement-1);
       if( rc==SQLITE_OK ){
-        rc = sqlite3BtreeBeginStmt(u.at.pBt, p->iStatement);
+        rc = sqlite3BtreeBeginStmt(u.au.pBt, p->iStatement);
       }
 
       /* Store the current value of the database handles deferred constraint
       ** counter. If the statement transaction needs to be rolled back,
       ** the value of this counter needs to be restored too.  */
       p->nStmtDefCons = db->nDeferredCons;
+      p->nStmtDefImmCons = db->nDeferredImmCons;
     }
   }
   break;
@@ -68716,21 +68471,22 @@ case OP_Transaction: {
 ** executing this instruction.
 */
 case OP_ReadCookie: {               /* out2-prerelease */
-#if 0  /* local variables moved into u.au */
+#if 0  /* local variables moved into u.av */
   int iMeta;
   int iDb;
   int iCookie;
-#endif /* local variables moved into u.au */
+#endif /* local variables moved into u.av */
 
-  u.au.iDb = pOp->p1;
-  u.au.iCookie = pOp->p3;
+  assert( p->bIsReader );
+  u.av.iDb = pOp->p1;
+  u.av.iCookie = pOp->p3;
   assert( pOp->p3<SQLITE_N_BTREE_META );
-  assert( u.au.iDb>=0 && u.au.iDb<db->nDb );
-  assert( db->aDb[u.au.iDb].pBt!=0 );
-  assert( (p->btreeMask & (((yDbMask)1)<<u.au.iDb))!=0 );
+  assert( u.av.iDb>=0 && u.av.iDb<db->nDb );
+  assert( db->aDb[u.av.iDb].pBt!=0 );
+  assert( (p->btreeMask & (((yDbMask)1)<<u.av.iDb))!=0 );
 
-  sqlite3BtreeGetMeta(db->aDb[u.au.iDb].pBt, u.au.iCookie, (u32 *)&u.au.iMeta);
-  pOut->u.i = u.au.iMeta;
+  sqlite3BtreeGetMeta(db->aDb[u.av.iDb].pBt, u.av.iCookie, (u32 *)&u.av.iMeta);
+  pOut->u.i = u.av.iMeta;
   break;
 }
 
@@ -68745,26 +68501,27 @@ case OP_ReadCookie: {               /* out2-prerelease */
 ** A transaction must be started before executing this opcode.
 */
 case OP_SetCookie: {       /* in3 */
-#if 0  /* local variables moved into u.av */
+#if 0  /* local variables moved into u.aw */
   Db *pDb;
-#endif /* local variables moved into u.av */
+#endif /* local variables moved into u.aw */
   assert( pOp->p2<SQLITE_N_BTREE_META );
   assert( pOp->p1>=0 && pOp->p1<db->nDb );
   assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
-  u.av.pDb = &db->aDb[pOp->p1];
-  assert( u.av.pDb->pBt!=0 );
+  assert( p->readOnly==0 );
+  u.aw.pDb = &db->aDb[pOp->p1];
+  assert( u.aw.pDb->pBt!=0 );
   assert( sqlite3SchemaMutexHeld(db, pOp->p1, 0) );
   pIn3 = &aMem[pOp->p3];
   sqlite3VdbeMemIntegerify(pIn3);
   /* See note about index shifting on OP_ReadCookie */
-  rc = sqlite3BtreeUpdateMeta(u.av.pDb->pBt, pOp->p2, (int)pIn3->u.i);
+  rc = sqlite3BtreeUpdateMeta(u.aw.pDb->pBt, pOp->p2, (int)pIn3->u.i);
   if( pOp->p2==BTREE_SCHEMA_VERSION ){
     /* When the schema cookie changes, record the new cookie internally */
-    u.av.pDb->pSchema->schema_cookie = (int)pIn3->u.i;
+    u.aw.pDb->pSchema->schema_cookie = (int)pIn3->u.i;
     db->flags |= SQLITE_InternChanges;
   }else if( pOp->p2==BTREE_FILE_FORMAT ){
     /* Record changes in the file format */
-    u.av.pDb->pSchema->file_format = (u8)pIn3->u.i;
+    u.aw.pDb->pSchema->file_format = (u8)pIn3->u.i;
   }
   if( pOp->p1==1 ){
     /* Invalidate all prepared statements whenever the TEMP database
@@ -68794,23 +68551,24 @@ case OP_SetCookie: {       /* in3 */
 ** invoked.
 */
 case OP_VerifyCookie: {
-#if 0  /* local variables moved into u.aw */
+#if 0  /* local variables moved into u.ax */
   int iMeta;
   int iGen;
   Btree *pBt;
-#endif /* local variables moved into u.aw */
+#endif /* local variables moved into u.ax */
 
   assert( pOp->p1>=0 && pOp->p1<db->nDb );
   assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
   assert( sqlite3SchemaMutexHeld(db, pOp->p1, 0) );
-  u.aw.pBt = db->aDb[pOp->p1].pBt;
-  if( u.aw.pBt ){
-    sqlite3BtreeGetMeta(u.aw.pBt, BTREE_SCHEMA_VERSION, (u32 *)&u.aw.iMeta);
-    u.aw.iGen = db->aDb[pOp->p1].pSchema->iGeneration;
+  assert( p->bIsReader );
+  u.ax.pBt = db->aDb[pOp->p1].pBt;
+  if( u.ax.pBt ){
+    sqlite3BtreeGetMeta(u.ax.pBt, BTREE_SCHEMA_VERSION, (u32 *)&u.ax.iMeta);
+    u.ax.iGen = db->aDb[pOp->p1].pSchema->iGeneration;
   }else{
-    u.aw.iGen = u.aw.iMeta = 0;
+    u.ax.iGen = u.ax.iMeta = 0;
   }
-  if( u.aw.iMeta!=pOp->p2 || u.aw.iGen!=pOp->p3 ){
+  if( u.ax.iMeta!=pOp->p2 || u.ax.iGen!=pOp->p3 ){
     sqlite3DbFree(db, p->zErrMsg);
     p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
     /* If the schema-cookie from the database file matches the cookie
@@ -68826,7 +68584,7 @@ case OP_VerifyCookie: {
     ** to be invalidated whenever sqlite3_step() is called from within
     ** a v-table method.
     */
-    if( db->aDb[pOp->p1].pSchema->schema_cookie!=u.aw.iMeta ){
+    if( db->aDb[pOp->p1].pSchema->schema_cookie!=u.ax.iMeta ){
       sqlite3ResetOneSchema(db, pOp->p1);
     }
 
@@ -68887,7 +68645,7 @@ case OP_VerifyCookie: {
 */
 case OP_OpenRead:
 case OP_OpenWrite: {
-#if 0  /* local variables moved into u.ax */
+#if 0  /* local variables moved into u.ay */
   int nField;
   KeyInfo *pKeyInfo;
   int p2;
@@ -68896,62 +68654,69 @@ case OP_OpenWrite: {
   Btree *pX;
   VdbeCursor *pCur;
   Db *pDb;
-#endif /* local variables moved into u.ax */
+#endif /* local variables moved into u.ay */
+
+  assert( (pOp->p5&(OPFLAG_P2ISREG|OPFLAG_BULKCSR))==pOp->p5 );
+  assert( pOp->opcode==OP_OpenWrite || pOp->p5==0 );
+  assert( p->bIsReader );
+  assert( pOp->opcode==OP_OpenRead || p->readOnly==0 );
 
   if( p->expired ){
     rc = SQLITE_ABORT;
     break;
   }
 
-  u.ax.nField = 0;
-  u.ax.pKeyInfo = 0;
-  u.ax.p2 = pOp->p2;
-  u.ax.iDb = pOp->p3;
-  assert( u.ax.iDb>=0 && u.ax.iDb<db->nDb );
-  assert( (p->btreeMask & (((yDbMask)1)<<u.ax.iDb))!=0 );
-  u.ax.pDb = &db->aDb[u.ax.iDb];
-  u.ax.pX = u.ax.pDb->pBt;
-  assert( u.ax.pX!=0 );
+  u.ay.nField = 0;
+  u.ay.pKeyInfo = 0;
+  u.ay.p2 = pOp->p2;
+  u.ay.iDb = pOp->p3;
+  assert( u.ay.iDb>=0 && u.ay.iDb<db->nDb );
+  assert( (p->btreeMask & (((yDbMask)1)<<u.ay.iDb))!=0 );
+  u.ay.pDb = &db->aDb[u.ay.iDb];
+  u.ay.pX = u.ay.pDb->pBt;
+  assert( u.ay.pX!=0 );
   if( pOp->opcode==OP_OpenWrite ){
-    u.ax.wrFlag = 1;
-    assert( sqlite3SchemaMutexHeld(db, u.ax.iDb, 0) );
-    if( u.ax.pDb->pSchema->file_format < p->minWriteFileFormat ){
-      p->minWriteFileFormat = u.ax.pDb->pSchema->file_format;
+    u.ay.wrFlag = 1;
+    assert( sqlite3SchemaMutexHeld(db, u.ay.iDb, 0) );
+    if( u.ay.pDb->pSchema->file_format < p->minWriteFileFormat ){
+      p->minWriteFileFormat = u.ay.pDb->pSchema->file_format;
     }
   }else{
-    u.ax.wrFlag = 0;
+    u.ay.wrFlag = 0;
   }
-  if( pOp->p5 ){
-    assert( u.ax.p2>0 );
-    assert( u.ax.p2<=p->nMem );
-    pIn2 = &aMem[u.ax.p2];
+  if( pOp->p5 & OPFLAG_P2ISREG ){
+    assert( u.ay.p2>0 );
+    assert( u.ay.p2<=p->nMem );
+    pIn2 = &aMem[u.ay.p2];
     assert( memIsValid(pIn2) );
     assert( (pIn2->flags & MEM_Int)!=0 );
     sqlite3VdbeMemIntegerify(pIn2);
-    u.ax.p2 = (int)pIn2->u.i;
-    /* The u.ax.p2 value always comes from a prior OP_CreateTable opcode and
-    ** that opcode will always set the u.ax.p2 value to 2 or more or else fail.
+    u.ay.p2 = (int)pIn2->u.i;
+    /* The u.ay.p2 value always comes from a prior OP_CreateTable opcode and
+    ** that opcode will always set the u.ay.p2 value to 2 or more or else fail.
     ** If there were a failure, the prepared statement would have halted
     ** before reaching this instruction. */
-    if( NEVER(u.ax.p2<2) ) {
+    if( NEVER(u.ay.p2<2) ) {
       rc = SQLITE_CORRUPT_BKPT;
       goto abort_due_to_error;
     }
   }
   if( pOp->p4type==P4_KEYINFO ){
-    u.ax.pKeyInfo = pOp->p4.pKeyInfo;
-    u.ax.pKeyInfo->enc = ENC(p->db);
-    u.ax.nField = u.ax.pKeyInfo->nField+1;
+    u.ay.pKeyInfo = pOp->p4.pKeyInfo;
+    u.ay.pKeyInfo->enc = ENC(p->db);
+    u.ay.nField = u.ay.pKeyInfo->nField+1;
   }else if( pOp->p4type==P4_INT32 ){
-    u.ax.nField = pOp->p4.i;
+    u.ay.nField = pOp->p4.i;
   }
   assert( pOp->p1>=0 );
-  u.ax.pCur = allocateCursor(p, pOp->p1, u.ax.nField, u.ax.iDb, 1);
-  if( u.ax.pCur==0 ) goto no_mem;
-  u.ax.pCur->nullRow = 1;
-  u.ax.pCur->isOrdered = 1;
-  rc = sqlite3BtreeCursor(u.ax.pX, u.ax.p2, u.ax.wrFlag, u.ax.pKeyInfo, u.ax.pCur->pCursor);
-  u.ax.pCur->pKeyInfo = u.ax.pKeyInfo;
+  u.ay.pCur = allocateCursor(p, pOp->p1, u.ay.nField, u.ay.iDb, 1);
+  if( u.ay.pCur==0 ) goto no_mem;
+  u.ay.pCur->nullRow = 1;
+  u.ay.pCur->isOrdered = 1;
+  rc = sqlite3BtreeCursor(u.ay.pX, u.ay.p2, u.ay.wrFlag, u.ay.pKeyInfo, u.ay.pCur->pCursor);
+  u.ay.pCur->pKeyInfo = u.ay.pKeyInfo;
+  assert( OPFLAG_BULKCSR==BTREE_BULKLOAD );
+  sqlite3BtreeCursorHints(u.ay.pCur->pCursor, (pOp->p5 & OPFLAG_BULKCSR));
 
   /* Since it performs no memory allocation or IO, the only value that
   ** sqlite3BtreeCursor() may return is SQLITE_OK. */
@@ -68961,8 +68726,8 @@ case OP_OpenWrite: {
   ** SQLite used to check if the root-page flags were sane at this point
   ** and report database corruption if they were not, but this check has
   ** since moved into the btree layer.  */
-  u.ax.pCur->isTable = pOp->p4type!=P4_KEYINFO;
-  u.ax.pCur->isIndex = !u.ax.pCur->isTable;
+  u.ay.pCur->isTable = pOp->p4type!=P4_KEYINFO;
+  u.ay.pCur->isIndex = !u.ay.pCur->isTable;
   break;
 }
 
@@ -68998,9 +68763,9 @@ case OP_OpenWrite: {
 */
 case OP_OpenAutoindex: 
 case OP_OpenEphemeral: {
-#if 0  /* local variables moved into u.ay */
+#if 0  /* local variables moved into u.az */
   VdbeCursor *pCx;
-#endif /* local variables moved into u.ay */
+#endif /* local variables moved into u.az */
   static const int vfsFlags =
       SQLITE_OPEN_READWRITE |
       SQLITE_OPEN_CREATE |
@@ -69009,13 +68774,13 @@ case OP_OpenEphemeral: {
       SQLITE_OPEN_TRANSIENT_DB;
 
   assert( pOp->p1>=0 );
-  u.ay.pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
-  if( u.ay.pCx==0 ) goto no_mem;
-  u.ay.pCx->nullRow = 1;
-  rc = sqlite3BtreeOpen(db->pVfs, 0, db, &u.ay.pCx->pBt,
+  u.az.pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
+  if( u.az.pCx==0 ) goto no_mem;
+  u.az.pCx->nullRow = 1;
+  rc = sqlite3BtreeOpen(db->pVfs, 0, db, &u.az.pCx->pBt,
                         BTREE_OMIT_JOURNAL | BTREE_SINGLE | pOp->p5, vfsFlags);
   if( rc==SQLITE_OK ){
-    rc = sqlite3BtreeBeginTrans(u.ay.pCx->pBt, 1);
+    rc = sqlite3BtreeBeginTrans(u.az.pCx->pBt, 1);
   }
   if( rc==SQLITE_OK ){
     /* If a transient index is required, create it by calling
@@ -69026,55 +68791,52 @@ case OP_OpenEphemeral: {
     if( pOp->p4.pKeyInfo ){
       int pgno;
       assert( pOp->p4type==P4_KEYINFO );
-      rc = sqlite3BtreeCreateTable(u.ay.pCx->pBt, &pgno, BTREE_BLOBKEY | pOp->p5);
+      rc = sqlite3BtreeCreateTable(u.az.pCx->pBt, &pgno, BTREE_BLOBKEY | pOp->p5);
       if( rc==SQLITE_OK ){
         assert( pgno==MASTER_ROOT+1 );
-        rc = sqlite3BtreeCursor(u.ay.pCx->pBt, pgno, 1,
-                                (KeyInfo*)pOp->p4.z, u.ay.pCx->pCursor);
-        u.ay.pCx->pKeyInfo = pOp->p4.pKeyInfo;
-        u.ay.pCx->pKeyInfo->enc = ENC(p->db);
+        rc = sqlite3BtreeCursor(u.az.pCx->pBt, pgno, 1,
+                                (KeyInfo*)pOp->p4.z, u.az.pCx->pCursor);
+        u.az.pCx->pKeyInfo = pOp->p4.pKeyInfo;
+        u.az.pCx->pKeyInfo->enc = ENC(p->db);
       }
-      u.ay.pCx->isTable = 0;
+      u.az.pCx->isTable = 0;
     }else{
-      rc = sqlite3BtreeCursor(u.ay.pCx->pBt, MASTER_ROOT, 1, 0, u.ay.pCx->pCursor);
-      u.ay.pCx->isTable = 1;
+      rc = sqlite3BtreeCursor(u.az.pCx->pBt, MASTER_ROOT, 1, 0, u.az.pCx->pCursor);
+      u.az.pCx->isTable = 1;
     }
   }
-  u.ay.pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
-  u.ay.pCx->isIndex = !u.ay.pCx->isTable;
+  u.az.pCx->isOrdered = (pOp->p5!=BTREE_UNORDERED);
+  u.az.pCx->isIndex = !u.az.pCx->isTable;
   break;
 }
 
-/* Opcode: OpenSorter P1 P2 * P4 *
+/* Opcode: SorterOpen P1 P2 * P4 *
 **
 ** This opcode works like OP_OpenEphemeral except that it opens
 ** a transient index that is specifically designed to sort large
 ** tables using an external merge-sort algorithm.
 */
 case OP_SorterOpen: {
-#if 0  /* local variables moved into u.az */
+#if 0  /* local variables moved into u.ba */
   VdbeCursor *pCx;
-#endif /* local variables moved into u.az */
-#ifndef SQLITE_OMIT_MERGE_SORT
-  u.az.pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
-  if( u.az.pCx==0 ) goto no_mem;
-  u.az.pCx->pKeyInfo = pOp->p4.pKeyInfo;
-  u.az.pCx->pKeyInfo->enc = ENC(p->db);
-  u.az.pCx->isSorter = 1;
-  rc = sqlite3VdbeSorterInit(db, u.az.pCx);
-#else
-  pOp->opcode = OP_OpenEphemeral;
-  pc--;
-#endif
+#endif /* local variables moved into u.ba */
+
+  u.ba.pCx = allocateCursor(p, pOp->p1, pOp->p2, -1, 1);
+  if( u.ba.pCx==0 ) goto no_mem;
+  u.ba.pCx->pKeyInfo = pOp->p4.pKeyInfo;
+  u.ba.pCx->pKeyInfo->enc = ENC(p->db);
+  u.ba.pCx->isSorter = 1;
+  rc = sqlite3VdbeSorterInit(db, u.ba.pCx);
   break;
 }
 
-/* Opcode: OpenPseudo P1 P2 P3 * *
+/* Opcode: OpenPseudo P1 P2 P3 * P5
 **
 ** Open a new cursor that points to a fake table that contains a single
 ** row of data.  The content of that one row in the content of memory
-** register P2.  In other words, cursor P1 becomes an alias for the 
-** MEM_Blob content contained in register P2.
+** register P2 when P5==0.  In other words, cursor P1 becomes an alias for the 
+** MEM_Blob content contained in register P2.  When P5==1, then the
+** row is represented by P3 consecutive registers beginning with P2.
 **
 ** A pseudo-table created by this opcode is used to hold a single
 ** row output from the sorter so that the row can be decomposed into
@@ -69085,17 +68847,18 @@ case OP_SorterOpen: {
 ** the pseudo-table.
 */
 case OP_OpenPseudo: {
-#if 0  /* local variables moved into u.ba */
+#if 0  /* local variables moved into u.bb */
   VdbeCursor *pCx;
-#endif /* local variables moved into u.ba */
+#endif /* local variables moved into u.bb */
 
   assert( pOp->p1>=0 );
-  u.ba.pCx = allocateCursor(p, pOp->p1, pOp->p3, -1, 0);
-  if( u.ba.pCx==0 ) goto no_mem;
-  u.ba.pCx->nullRow = 1;
-  u.ba.pCx->pseudoTableReg = pOp->p2;
-  u.ba.pCx->isTable = 1;
-  u.ba.pCx->isIndex = 0;
+  u.bb.pCx = allocateCursor(p, pOp->p1, pOp->p3, -1, 0);
+  if( u.bb.pCx==0 ) goto no_mem;
+  u.bb.pCx->nullRow = 1;
+  u.bb.pCx->pseudoTableReg = pOp->p2;
+  u.bb.pCx->isTable = 1;
+  u.bb.pCx->isIndex = 0;
+  u.bb.pCx->multiPseudo = pOp->p5;
   break;
 }
 
@@ -69167,35 +68930,35 @@ case OP_SeekLt:         /* jump, in3 */
 case OP_SeekLe:         /* jump, in3 */
 case OP_SeekGe:         /* jump, in3 */
 case OP_SeekGt: {       /* jump, in3 */
-#if 0  /* local variables moved into u.bb */
+#if 0  /* local variables moved into u.bc */
   int res;
   int oc;
   VdbeCursor *pC;
   UnpackedRecord r;
   int nField;
   i64 iKey;      /* The rowid we are to seek to */
-#endif /* local variables moved into u.bb */
+#endif /* local variables moved into u.bc */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   assert( pOp->p2!=0 );
-  u.bb.pC = p->apCsr[pOp->p1];
-  assert( u.bb.pC!=0 );
-  assert( u.bb.pC->pseudoTableReg==0 );
+  u.bc.pC = p->apCsr[pOp->p1];
+  assert( u.bc.pC!=0 );
+  assert( u.bc.pC->pseudoTableReg==0 );
   assert( OP_SeekLe == OP_SeekLt+1 );
   assert( OP_SeekGe == OP_SeekLt+2 );
   assert( OP_SeekGt == OP_SeekLt+3 );
-  assert( u.bb.pC->isOrdered );
-  if( ALWAYS(u.bb.pC->pCursor!=0) ){
-    u.bb.oc = pOp->opcode;
-    u.bb.pC->nullRow = 0;
-    if( u.bb.pC->isTable ){
+  assert( u.bc.pC->isOrdered );
+  if( ALWAYS(u.bc.pC->pCursor!=0) ){
+    u.bc.oc = pOp->opcode;
+    u.bc.pC->nullRow = 0;
+    if( u.bc.pC->isTable ){
       /* The input value in P3 might be of any type: integer, real, string,
       ** blob, or NULL.  But it needs to be an integer before we can do
       ** the seek, so covert it. */
       pIn3 = &aMem[pOp->p3];
       applyNumericAffinity(pIn3);
-      u.bb.iKey = sqlite3VdbeIntValue(pIn3);
-      u.bb.pC->rowidIsValid = 0;
+      u.bc.iKey = sqlite3VdbeIntValue(pIn3);
+      u.bc.pC->rowidIsValid = 0;
 
       /* If the P3 value could not be converted into an integer without
       ** loss of information, then special processing is required... */
@@ -69210,101 +68973,101 @@ case OP_SeekGt: {       /* jump, in3 */
         ** point number. */
         assert( (pIn3->flags & MEM_Real)!=0 );
 
-        if( u.bb.iKey==SMALLEST_INT64 && (pIn3->r<(double)u.bb.iKey || pIn3->r>0) ){
+        if( u.bc.iKey==SMALLEST_INT64 && (pIn3->r<(double)u.bc.iKey || pIn3->r>0) ){
           /* The P3 value is too large in magnitude to be expressed as an
           ** integer. */
-          u.bb.res = 1;
+          u.bc.res = 1;
           if( pIn3->r<0 ){
-            if( u.bb.oc>=OP_SeekGe ){  assert( u.bb.oc==OP_SeekGe || u.bb.oc==OP_SeekGt );
-              rc = sqlite3BtreeFirst(u.bb.pC->pCursor, &u.bb.res);
+            if( u.bc.oc>=OP_SeekGe ){  assert( u.bc.oc==OP_SeekGe || u.bc.oc==OP_SeekGt );
+              rc = sqlite3BtreeFirst(u.bc.pC->pCursor, &u.bc.res);
               if( rc!=SQLITE_OK ) goto abort_due_to_error;
             }
           }else{
-            if( u.bb.oc<=OP_SeekLe ){  assert( u.bb.oc==OP_SeekLt || u.bb.oc==OP_SeekLe );
-              rc = sqlite3BtreeLast(u.bb.pC->pCursor, &u.bb.res);
+            if( u.bc.oc<=OP_SeekLe ){  assert( u.bc.oc==OP_SeekLt || u.bc.oc==OP_SeekLe );
+              rc = sqlite3BtreeLast(u.bc.pC->pCursor, &u.bc.res);
               if( rc!=SQLITE_OK ) goto abort_due_to_error;
             }
           }
-          if( u.bb.res ){
+          if( u.bc.res ){
             pc = pOp->p2 - 1;
           }
           break;
-        }else if( u.bb.oc==OP_SeekLt || u.bb.oc==OP_SeekGe ){
+        }else if( u.bc.oc==OP_SeekLt || u.bc.oc==OP_SeekGe ){
           /* Use the ceiling() function to convert real->int */
-          if( pIn3->r > (double)u.bb.iKey ) u.bb.iKey++;
+          if( pIn3->r > (double)u.bc.iKey ) u.bc.iKey++;
         }else{
           /* Use the floor() function to convert real->int */
-          assert( u.bb.oc==OP_SeekLe || u.bb.oc==OP_SeekGt );
-          if( pIn3->r < (double)u.bb.iKey ) u.bb.iKey--;
+          assert( u.bc.oc==OP_SeekLe || u.bc.oc==OP_SeekGt );
+          if( pIn3->r < (double)u.bc.iKey ) u.bc.iKey--;
         }
       }
-      rc = sqlite3BtreeMovetoUnpacked(u.bb.pC->pCursor, 0, (u64)u.bb.iKey, 0, &u.bb.res);
+      rc = sqlite3BtreeMovetoUnpacked(u.bc.pC->pCursor, 0, (u64)u.bc.iKey, 0, &u.bc.res);
       if( rc!=SQLITE_OK ){
         goto abort_due_to_error;
       }
-      if( u.bb.res==0 ){
-        u.bb.pC->rowidIsValid = 1;
-        u.bb.pC->lastRowid = u.bb.iKey;
+      if( u.bc.res==0 ){
+        u.bc.pC->rowidIsValid = 1;
+        u.bc.pC->lastRowid = u.bc.iKey;
       }
     }else{
-      u.bb.nField = pOp->p4.i;
+      u.bc.nField = pOp->p4.i;
       assert( pOp->p4type==P4_INT32 );
-      assert( u.bb.nField>0 );
-      u.bb.r.pKeyInfo = u.bb.pC->pKeyInfo;
-      u.bb.r.nField = (u16)u.bb.nField;
+      assert( u.bc.nField>0 );
+      u.bc.r.pKeyInfo = u.bc.pC->pKeyInfo;
+      u.bc.r.nField = (u16)u.bc.nField;
 
       /* The next line of code computes as follows, only faster:
-      **   if( u.bb.oc==OP_SeekGt || u.bb.oc==OP_SeekLe ){
-      **     u.bb.r.flags = UNPACKED_INCRKEY;
+      **   if( u.bc.oc==OP_SeekGt || u.bc.oc==OP_SeekLe ){
+      **     u.bc.r.flags = UNPACKED_INCRKEY;
       **   }else{
-      **     u.bb.r.flags = 0;
+      **     u.bc.r.flags = 0;
       **   }
       */
-      u.bb.r.flags = (u16)(UNPACKED_INCRKEY * (1 & (u.bb.oc - OP_SeekLt)));
-      assert( u.bb.oc!=OP_SeekGt || u.bb.r.flags==UNPACKED_INCRKEY );
-      assert( u.bb.oc!=OP_SeekLe || u.bb.r.flags==UNPACKED_INCRKEY );
-      assert( u.bb.oc!=OP_SeekGe || u.bb.r.flags==0 );
-      assert( u.bb.oc!=OP_SeekLt || u.bb.r.flags==0 );
+      u.bc.r.flags = (u8)(UNPACKED_INCRKEY * (1 & (u.bc.oc - OP_SeekLt)));
+      assert( u.bc.oc!=OP_SeekGt || u.bc.r.flags==UNPACKED_INCRKEY );
+      assert( u.bc.oc!=OP_SeekLe || u.bc.r.flags==UNPACKED_INCRKEY );
+      assert( u.bc.oc!=OP_SeekGe || u.bc.r.flags==0 );
+      assert( u.bc.oc!=OP_SeekLt || u.bc.r.flags==0 );
 
-      u.bb.r.aMem = &aMem[pOp->p3];
+      u.bc.r.aMem = &aMem[pOp->p3];
 #ifdef SQLITE_DEBUG
-      { int i; for(i=0; i<u.bb.r.nField; i++) assert( memIsValid(&u.bb.r.aMem[i]) ); }
+      { int i; for(i=0; i<u.bc.r.nField; i++) assert( memIsValid(&u.bc.r.aMem[i]) ); }
 #endif
-      ExpandBlob(u.bb.r.aMem);
-      rc = sqlite3BtreeMovetoUnpacked(u.bb.pC->pCursor, &u.bb.r, 0, 0, &u.bb.res);
+      ExpandBlob(u.bc.r.aMem);
+      rc = sqlite3BtreeMovetoUnpacked(u.bc.pC->pCursor, &u.bc.r, 0, 0, &u.bc.res);
       if( rc!=SQLITE_OK ){
         goto abort_due_to_error;
       }
-      u.bb.pC->rowidIsValid = 0;
+      u.bc.pC->rowidIsValid = 0;
     }
-    u.bb.pC->deferredMoveto = 0;
-    u.bb.pC->cacheStatus = CACHE_STALE;
+    u.bc.pC->deferredMoveto = 0;
+    u.bc.pC->cacheStatus = CACHE_STALE;
 #ifdef SQLITE_TEST
     sqlite3_search_count++;
 #endif
-    if( u.bb.oc>=OP_SeekGe ){  assert( u.bb.oc==OP_SeekGe || u.bb.oc==OP_SeekGt );
-      if( u.bb.res<0 || (u.bb.res==0 && u.bb.oc==OP_SeekGt) ){
-        rc = sqlite3BtreeNext(u.bb.pC->pCursor, &u.bb.res);
+    if( u.bc.oc>=OP_SeekGe ){  assert( u.bc.oc==OP_SeekGe || u.bc.oc==OP_SeekGt );
+      if( u.bc.res<0 || (u.bc.res==0 && u.bc.oc==OP_SeekGt) ){
+        rc = sqlite3BtreeNext(u.bc.pC->pCursor, &u.bc.res);
         if( rc!=SQLITE_OK ) goto abort_due_to_error;
-        u.bb.pC->rowidIsValid = 0;
+        u.bc.pC->rowidIsValid = 0;
       }else{
-        u.bb.res = 0;
+        u.bc.res = 0;
       }
     }else{
-      assert( u.bb.oc==OP_SeekLt || u.bb.oc==OP_SeekLe );
-      if( u.bb.res>0 || (u.bb.res==0 && u.bb.oc==OP_SeekLt) ){
-        rc = sqlite3BtreePrevious(u.bb.pC->pCursor, &u.bb.res);
+      assert( u.bc.oc==OP_SeekLt || u.bc.oc==OP_SeekLe );
+      if( u.bc.res>0 || (u.bc.res==0 && u.bc.oc==OP_SeekLt) ){
+        rc = sqlite3BtreePrevious(u.bc.pC->pCursor, &u.bc.res);
         if( rc!=SQLITE_OK ) goto abort_due_to_error;
-        u.bb.pC->rowidIsValid = 0;
+        u.bc.pC->rowidIsValid = 0;
       }else{
-        /* u.bb.res might be negative because the table is empty.  Check to
+        /* u.bc.res might be negative because the table is empty.  Check to
         ** see if this is the case.
         */
-        u.bb.res = sqlite3BtreeEof(u.bb.pC->pCursor);
+        u.bc.res = sqlite3BtreeEof(u.bc.pC->pCursor);
       }
     }
     assert( pOp->p2>0 );
-    if( u.bb.res ){
+    if( u.bc.res ){
       pc = pOp->p2 - 1;
     }
   }else{
@@ -69327,20 +69090,20 @@ case OP_SeekGt: {       /* jump, in3 */
 ** occur, no unnecessary I/O happens.
 */
 case OP_Seek: {    /* in2 */
-#if 0  /* local variables moved into u.bc */
+#if 0  /* local variables moved into u.bd */
   VdbeCursor *pC;
-#endif /* local variables moved into u.bc */
+#endif /* local variables moved into u.bd */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bc.pC = p->apCsr[pOp->p1];
-  assert( u.bc.pC!=0 );
-  if( ALWAYS(u.bc.pC->pCursor!=0) ){
-    assert( u.bc.pC->isTable );
-    u.bc.pC->nullRow = 0;
+  u.bd.pC = p->apCsr[pOp->p1];
+  assert( u.bd.pC!=0 );
+  if( ALWAYS(u.bd.pC->pCursor!=0) ){
+    assert( u.bd.pC->isTable );
+    u.bd.pC->nullRow = 0;
     pIn2 = &aMem[pOp->p2];
-    u.bc.pC->movetoTarget = sqlite3VdbeIntValue(pIn2);
-    u.bc.pC->rowidIsValid = 0;
-    u.bc.pC->deferredMoveto = 1;
+    u.bd.pC->movetoTarget = sqlite3VdbeIntValue(pIn2);
+    u.bd.pC->rowidIsValid = 0;
+    u.bd.pC->deferredMoveto = 1;
   }
   break;
 }
@@ -69372,7 +69135,7 @@ case OP_Seek: {    /* in2 */
 */
 case OP_NotFound:       /* jump, in3 */
 case OP_Found: {        /* jump, in3 */
-#if 0  /* local variables moved into u.bd */
+#if 0  /* local variables moved into u.be */
   int alreadyExists;
   VdbeCursor *pC;
   int res;
@@ -69380,55 +69143,55 @@ case OP_Found: {        /* jump, in3 */
   UnpackedRecord *pIdxKey;
   UnpackedRecord r;
   char aTempRec[ROUND8(sizeof(UnpackedRecord)) + sizeof(Mem)*3 + 7];
-#endif /* local variables moved into u.bd */
+#endif /* local variables moved into u.be */
 
 #ifdef SQLITE_TEST
   sqlite3_found_count++;
 #endif
 
-  u.bd.alreadyExists = 0;
+  u.be.alreadyExists = 0;
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
   assert( pOp->p4type==P4_INT32 );
-  u.bd.pC = p->apCsr[pOp->p1];
-  assert( u.bd.pC!=0 );
+  u.be.pC = p->apCsr[pOp->p1];
+  assert( u.be.pC!=0 );
   pIn3 = &aMem[pOp->p3];
-  if( ALWAYS(u.bd.pC->pCursor!=0) ){
+  if( ALWAYS(u.be.pC->pCursor!=0) ){
 
-    assert( u.bd.pC->isTable==0 );
+    assert( u.be.pC->isTable==0 );
     if( pOp->p4.i>0 ){
-      u.bd.r.pKeyInfo = u.bd.pC->pKeyInfo;
-      u.bd.r.nField = (u16)pOp->p4.i;
-      u.bd.r.aMem = pIn3;
+      u.be.r.pKeyInfo = u.be.pC->pKeyInfo;
+      u.be.r.nField = (u16)pOp->p4.i;
+      u.be.r.aMem = pIn3;
 #ifdef SQLITE_DEBUG
-      { int i; for(i=0; i<u.bd.r.nField; i++) assert( memIsValid(&u.bd.r.aMem[i]) ); }
+      { int i; for(i=0; i<u.be.r.nField; i++) assert( memIsValid(&u.be.r.aMem[i]) ); }
 #endif
-      u.bd.r.flags = UNPACKED_PREFIX_MATCH;
-      u.bd.pIdxKey = &u.bd.r;
+      u.be.r.flags = UNPACKED_PREFIX_MATCH;
+      u.be.pIdxKey = &u.be.r;
     }else{
-      u.bd.pIdxKey = sqlite3VdbeAllocUnpackedRecord(
-          u.bd.pC->pKeyInfo, u.bd.aTempRec, sizeof(u.bd.aTempRec), &u.bd.pFree
+      u.be.pIdxKey = sqlite3VdbeAllocUnpackedRecord(
+          u.be.pC->pKeyInfo, u.be.aTempRec, sizeof(u.be.aTempRec), &u.be.pFree
       );
-      if( u.bd.pIdxKey==0 ) goto no_mem;
+      if( u.be.pIdxKey==0 ) goto no_mem;
       assert( pIn3->flags & MEM_Blob );
       assert( (pIn3->flags & MEM_Zero)==0 );  /* zeroblobs already expanded */
-      sqlite3VdbeRecordUnpack(u.bd.pC->pKeyInfo, pIn3->n, pIn3->z, u.bd.pIdxKey);
-      u.bd.pIdxKey->flags |= UNPACKED_PREFIX_MATCH;
+      sqlite3VdbeRecordUnpack(u.be.pC->pKeyInfo, pIn3->n, pIn3->z, u.be.pIdxKey);
+      u.be.pIdxKey->flags |= UNPACKED_PREFIX_MATCH;
     }
-    rc = sqlite3BtreeMovetoUnpacked(u.bd.pC->pCursor, u.bd.pIdxKey, 0, 0, &u.bd.res);
+    rc = sqlite3BtreeMovetoUnpacked(u.be.pC->pCursor, u.be.pIdxKey, 0, 0, &u.be.res);
     if( pOp->p4.i==0 ){
-      sqlite3DbFree(db, u.bd.pFree);
+      sqlite3DbFree(db, u.be.pFree);
     }
     if( rc!=SQLITE_OK ){
       break;
     }
-    u.bd.alreadyExists = (u.bd.res==0);
-    u.bd.pC->deferredMoveto = 0;
-    u.bd.pC->cacheStatus = CACHE_STALE;
+    u.be.alreadyExists = (u.be.res==0);
+    u.be.pC->deferredMoveto = 0;
+    u.be.pC->cacheStatus = CACHE_STALE;
   }
   if( pOp->opcode==OP_Found ){
-    if( u.bd.alreadyExists ) pc = pOp->p2 - 1;
+    if( u.be.alreadyExists ) pc = pOp->p2 - 1;
   }else{
-    if( !u.bd.alreadyExists ) pc = pOp->p2 - 1;
+    if( !u.be.alreadyExists ) pc = pOp->p2 - 1;
   }
   break;
 }
@@ -69460,7 +69223,7 @@ case OP_Found: {        /* jump, in3 */
 ** See also: NotFound, NotExists, Found
 */
 case OP_IsUnique: {        /* jump, in3 */
-#if 0  /* local variables moved into u.be */
+#if 0  /* local variables moved into u.bf */
   u16 ii;
   VdbeCursor *pCx;
   BtCursor *pCrsr;
@@ -69468,55 +69231,55 @@ case OP_IsUnique: {        /* jump, in3 */
   Mem *aMx;
   UnpackedRecord r;                  /* B-Tree index search key */
   i64 R;                             /* Rowid stored in register P3 */
-#endif /* local variables moved into u.be */
+#endif /* local variables moved into u.bf */
 
   pIn3 = &aMem[pOp->p3];
-  u.be.aMx = &aMem[pOp->p4.i];
+  u.bf.aMx = &aMem[pOp->p4.i];
   /* Assert that the values of parameters P1 and P4 are in range. */
   assert( pOp->p4type==P4_INT32 );
   assert( pOp->p4.i>0 && pOp->p4.i<=p->nMem );
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
 
   /* Find the index cursor. */
-  u.be.pCx = p->apCsr[pOp->p1];
-  assert( u.be.pCx->deferredMoveto==0 );
-  u.be.pCx->seekResult = 0;
-  u.be.pCx->cacheStatus = CACHE_STALE;
-  u.be.pCrsr = u.be.pCx->pCursor;
+  u.bf.pCx = p->apCsr[pOp->p1];
+  assert( u.bf.pCx->deferredMoveto==0 );
+  u.bf.pCx->seekResult = 0;
+  u.bf.pCx->cacheStatus = CACHE_STALE;
+  u.bf.pCrsr = u.bf.pCx->pCursor;
 
   /* If any of the values are NULL, take the jump. */
-  u.be.nField = u.be.pCx->pKeyInfo->nField;
-  for(u.be.ii=0; u.be.ii<u.be.nField; u.be.ii++){
-    if( u.be.aMx[u.be.ii].flags & MEM_Null ){
+  u.bf.nField = u.bf.pCx->pKeyInfo->nField;
+  for(u.bf.ii=0; u.bf.ii<u.bf.nField; u.bf.ii++){
+    if( u.bf.aMx[u.bf.ii].flags & MEM_Null ){
       pc = pOp->p2 - 1;
-      u.be.pCrsr = 0;
+      u.bf.pCrsr = 0;
       break;
     }
   }
-  assert( (u.be.aMx[u.be.nField].flags & MEM_Null)==0 );
+  assert( (u.bf.aMx[u.bf.nField].flags & MEM_Null)==0 );
 
-  if( u.be.pCrsr!=0 ){
+  if( u.bf.pCrsr!=0 ){
     /* Populate the index search key. */
-    u.be.r.pKeyInfo = u.be.pCx->pKeyInfo;
-    u.be.r.nField = u.be.nField + 1;
-    u.be.r.flags = UNPACKED_PREFIX_SEARCH;
-    u.be.r.aMem = u.be.aMx;
+    u.bf.r.pKeyInfo = u.bf.pCx->pKeyInfo;
+    u.bf.r.nField = u.bf.nField + 1;
+    u.bf.r.flags = UNPACKED_PREFIX_SEARCH;
+    u.bf.r.aMem = u.bf.aMx;
 #ifdef SQLITE_DEBUG
-    { int i; for(i=0; i<u.be.r.nField; i++) assert( memIsValid(&u.be.r.aMem[i]) ); }
+    { int i; for(i=0; i<u.bf.r.nField; i++) assert( memIsValid(&u.bf.r.aMem[i]) ); }
 #endif
 
-    /* Extract the value of u.be.R from register P3. */
+    /* Extract the value of u.bf.R from register P3. */
     sqlite3VdbeMemIntegerify(pIn3);
-    u.be.R = pIn3->u.i;
+    u.bf.R = pIn3->u.i;
 
     /* Search the B-Tree index. If no conflicting record is found, jump
     ** to P2. Otherwise, copy the rowid of the conflicting record to
     ** register P3 and fall through to the next instruction.  */
-    rc = sqlite3BtreeMovetoUnpacked(u.be.pCrsr, &u.be.r, 0, 0, &u.be.pCx->seekResult);
-    if( (u.be.r.flags & UNPACKED_PREFIX_SEARCH) || u.be.r.rowid==u.be.R ){
+    rc = sqlite3BtreeMovetoUnpacked(u.bf.pCrsr, &u.bf.r, 0, 0, &u.bf.pCx->seekResult);
+    if( (u.bf.r.flags & UNPACKED_PREFIX_SEARCH) || u.bf.r.rowid==u.bf.R ){
       pc = pOp->p2 - 1;
     }else{
-      pIn3->u.i = u.be.r.rowid;
+      pIn3->u.i = u.bf.r.rowid;
     }
   }
   break;
@@ -69537,42 +69300,42 @@ case OP_IsUnique: {        /* jump, in3 */
 ** See also: Found, NotFound, IsUnique
 */
 case OP_NotExists: {        /* jump, in3 */
-#if 0  /* local variables moved into u.bf */
+#if 0  /* local variables moved into u.bg */
   VdbeCursor *pC;
   BtCursor *pCrsr;
   int res;
   u64 iKey;
-#endif /* local variables moved into u.bf */
+#endif /* local variables moved into u.bg */
 
   pIn3 = &aMem[pOp->p3];
   assert( pIn3->flags & MEM_Int );
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bf.pC = p->apCsr[pOp->p1];
-  assert( u.bf.pC!=0 );
-  assert( u.bf.pC->isTable );
-  assert( u.bf.pC->pseudoTableReg==0 );
-  u.bf.pCrsr = u.bf.pC->pCursor;
-  if( ALWAYS(u.bf.pCrsr!=0) ){
-    u.bf.res = 0;
-    u.bf.iKey = pIn3->u.i;
-    rc = sqlite3BtreeMovetoUnpacked(u.bf.pCrsr, 0, u.bf.iKey, 0, &u.bf.res);
-    u.bf.pC->lastRowid = pIn3->u.i;
-    u.bf.pC->rowidIsValid = u.bf.res==0 ?1:0;
-    u.bf.pC->nullRow = 0;
-    u.bf.pC->cacheStatus = CACHE_STALE;
-    u.bf.pC->deferredMoveto = 0;
-    if( u.bf.res!=0 ){
+  u.bg.pC = p->apCsr[pOp->p1];
+  assert( u.bg.pC!=0 );
+  assert( u.bg.pC->isTable );
+  assert( u.bg.pC->pseudoTableReg==0 );
+  u.bg.pCrsr = u.bg.pC->pCursor;
+  if( ALWAYS(u.bg.pCrsr!=0) ){
+    u.bg.res = 0;
+    u.bg.iKey = pIn3->u.i;
+    rc = sqlite3BtreeMovetoUnpacked(u.bg.pCrsr, 0, u.bg.iKey, 0, &u.bg.res);
+    u.bg.pC->lastRowid = pIn3->u.i;
+    u.bg.pC->rowidIsValid = u.bg.res==0 ?1:0;
+    u.bg.pC->nullRow = 0;
+    u.bg.pC->cacheStatus = CACHE_STALE;
+    u.bg.pC->deferredMoveto = 0;
+    if( u.bg.res!=0 ){
       pc = pOp->p2 - 1;
-      assert( u.bf.pC->rowidIsValid==0 );
+      assert( u.bg.pC->rowidIsValid==0 );
     }
-    u.bf.pC->seekResult = u.bf.res;
+    u.bg.pC->seekResult = u.bg.res;
   }else{
     /* This happens when an attempt to open a read cursor on the
     ** sqlite_master table returns SQLITE_EMPTY.
     */
     pc = pOp->p2 - 1;
-    assert( u.bf.pC->rowidIsValid==0 );
-    u.bf.pC->seekResult = 0;
+    assert( u.bg.pC->rowidIsValid==0 );
+    u.bg.pC->seekResult = 0;
   }
   break;
 }
@@ -69607,21 +69370,21 @@ case OP_Sequence: {           /* out2-prerelease */
 ** AUTOINCREMENT feature.
 */
 case OP_NewRowid: {           /* out2-prerelease */
-#if 0  /* local variables moved into u.bg */
+#if 0  /* local variables moved into u.bh */
   i64 v;                 /* The new rowid */
   VdbeCursor *pC;        /* Cursor of table to get the new rowid */
   int res;               /* Result of an sqlite3BtreeLast() */
   int cnt;               /* Counter to limit the number of searches */
   Mem *pMem;             /* Register holding largest rowid for AUTOINCREMENT */
   VdbeFrame *pFrame;     /* Root frame of VDBE */
-#endif /* local variables moved into u.bg */
+#endif /* local variables moved into u.bh */
 
-  u.bg.v = 0;
-  u.bg.res = 0;
+  u.bh.v = 0;
+  u.bh.res = 0;
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bg.pC = p->apCsr[pOp->p1];
-  assert( u.bg.pC!=0 );
-  if( NEVER(u.bg.pC->pCursor==0) ){
+  u.bh.pC = p->apCsr[pOp->p1];
+  assert( u.bh.pC!=0 );
+  if( NEVER(u.bh.pC->pCursor==0) ){
     /* The zero initialization above is all that is needed */
   }else{
     /* The next rowid or record number (different terms for the same
@@ -69637,7 +69400,7 @@ case OP_NewRowid: {           /* out2-prerelease */
     ** succeeded.  If the random rowid does exist, we select a new one
     ** and try again, up to 100 times.
     */
-    assert( u.bg.pC->isTable );
+    assert( u.bh.pC->isTable );
 
 #ifdef SQLITE_32BIT_ROWID
 #   define MAX_ROWID 0x7fffffff
@@ -69649,23 +69412,23 @@ case OP_NewRowid: {           /* out2-prerelease */
 #   define MAX_ROWID  (i64)( (((u64)0x7fffffff)<<32) | (u64)0xffffffff )
 #endif
 
-    if( !u.bg.pC->useRandomRowid ){
-      u.bg.v = sqlite3BtreeGetCachedRowid(u.bg.pC->pCursor);
-      if( u.bg.v==0 ){
-        rc = sqlite3BtreeLast(u.bg.pC->pCursor, &u.bg.res);
+    if( !u.bh.pC->useRandomRowid ){
+      u.bh.v = sqlite3BtreeGetCachedRowid(u.bh.pC->pCursor);
+      if( u.bh.v==0 ){
+        rc = sqlite3BtreeLast(u.bh.pC->pCursor, &u.bh.res);
         if( rc!=SQLITE_OK ){
           goto abort_due_to_error;
         }
-        if( u.bg.res ){
-          u.bg.v = 1;   /* IMP: R-61914-48074 */
+        if( u.bh.res ){
+          u.bh.v = 1;   /* IMP: R-61914-48074 */
         }else{
-          assert( sqlite3BtreeCursorIsValid(u.bg.pC->pCursor) );
-          rc = sqlite3BtreeKeySize(u.bg.pC->pCursor, &u.bg.v);
+          assert( sqlite3BtreeCursorIsValid(u.bh.pC->pCursor) );
+          rc = sqlite3BtreeKeySize(u.bh.pC->pCursor, &u.bh.v);
           assert( rc==SQLITE_OK );   /* Cannot fail following BtreeLast() */
-          if( u.bg.v>=MAX_ROWID ){
-            u.bg.pC->useRandomRowid = 1;
+          if( u.bh.v>=MAX_ROWID ){
+            u.bh.pC->useRandomRowid = 1;
           }else{
-            u.bg.v++;   /* IMP: R-29538-34987 */
+            u.bh.v++;   /* IMP: R-29538-34987 */
           }
         }
       }
@@ -69675,35 +69438,35 @@ case OP_NewRowid: {           /* out2-prerelease */
         /* Assert that P3 is a valid memory cell. */
         assert( pOp->p3>0 );
         if( p->pFrame ){
-          for(u.bg.pFrame=p->pFrame; u.bg.pFrame->pParent; u.bg.pFrame=u.bg.pFrame->pParent);
+          for(u.bh.pFrame=p->pFrame; u.bh.pFrame->pParent; u.bh.pFrame=u.bh.pFrame->pParent);
           /* Assert that P3 is a valid memory cell. */
-          assert( pOp->p3<=u.bg.pFrame->nMem );
-          u.bg.pMem = &u.bg.pFrame->aMem[pOp->p3];
+          assert( pOp->p3<=u.bh.pFrame->nMem );
+          u.bh.pMem = &u.bh.pFrame->aMem[pOp->p3];
         }else{
           /* Assert that P3 is a valid memory cell. */
           assert( pOp->p3<=p->nMem );
-          u.bg.pMem = &aMem[pOp->p3];
-          memAboutToChange(p, u.bg.pMem);
+          u.bh.pMem = &aMem[pOp->p3];
+          memAboutToChange(p, u.bh.pMem);
         }
-        assert( memIsValid(u.bg.pMem) );
+        assert( memIsValid(u.bh.pMem) );
 
-        REGISTER_TRACE(pOp->p3, u.bg.pMem);
-        sqlite3VdbeMemIntegerify(u.bg.pMem);
-        assert( (u.bg.pMem->flags & MEM_Int)!=0 );  /* mem(P3) holds an integer */
-        if( u.bg.pMem->u.i==MAX_ROWID || u.bg.pC->useRandomRowid ){
+        REGISTER_TRACE(pOp->p3, u.bh.pMem);
+        sqlite3VdbeMemIntegerify(u.bh.pMem);
+        assert( (u.bh.pMem->flags & MEM_Int)!=0 );  /* mem(P3) holds an integer */
+        if( u.bh.pMem->u.i==MAX_ROWID || u.bh.pC->useRandomRowid ){
           rc = SQLITE_FULL;   /* IMP: R-12275-61338 */
           goto abort_due_to_error;
         }
-        if( u.bg.v<u.bg.pMem->u.i+1 ){
-          u.bg.v = u.bg.pMem->u.i + 1;
+        if( u.bh.v<u.bh.pMem->u.i+1 ){
+          u.bh.v = u.bh.pMem->u.i + 1;
         }
-        u.bg.pMem->u.i = u.bg.v;
+        u.bh.pMem->u.i = u.bh.v;
       }
 #endif
 
-      sqlite3BtreeSetCachedRowid(u.bg.pC->pCursor, u.bg.v<MAX_ROWID ? u.bg.v+1 : 0);
+      sqlite3BtreeSetCachedRowid(u.bh.pC->pCursor, u.bh.v<MAX_ROWID ? u.bh.v+1 : 0);
     }
-    if( u.bg.pC->useRandomRowid ){
+    if( u.bh.pC->useRandomRowid ){
       /* IMPLEMENTATION-OF: R-07677-41881 If the largest ROWID is equal to the
       ** largest possible integer (9223372036854775807) then the database
       ** engine starts picking positive candidate ROWIDs at random until
@@ -69711,35 +69474,35 @@ case OP_NewRowid: {           /* out2-prerelease */
       assert( pOp->p3==0 );  /* We cannot be in random rowid mode if this is
                              ** an AUTOINCREMENT table. */
       /* on the first attempt, simply do one more than previous */
-      u.bg.v = lastRowid;
-      u.bg.v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
-      u.bg.v++; /* ensure non-zero */
-      u.bg.cnt = 0;
-      while(   ((rc = sqlite3BtreeMovetoUnpacked(u.bg.pC->pCursor, 0, (u64)u.bg.v,
-                                                 0, &u.bg.res))==SQLITE_OK)
-            && (u.bg.res==0)
-            && (++u.bg.cnt<100)){
+      u.bh.v = lastRowid;
+      u.bh.v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
+      u.bh.v++; /* ensure non-zero */
+      u.bh.cnt = 0;
+      while(   ((rc = sqlite3BtreeMovetoUnpacked(u.bh.pC->pCursor, 0, (u64)u.bh.v,
+                                                 0, &u.bh.res))==SQLITE_OK)
+            && (u.bh.res==0)
+            && (++u.bh.cnt<100)){
         /* collision - try another random rowid */
-        sqlite3_randomness(sizeof(u.bg.v), &u.bg.v);
-        if( u.bg.cnt<5 ){
+        sqlite3_randomness(sizeof(u.bh.v), &u.bh.v);
+        if( u.bh.cnt<5 ){
           /* try "small" random rowids for the initial attempts */
-          u.bg.v &= 0xffffff;
+          u.bh.v &= 0xffffff;
         }else{
-          u.bg.v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
+          u.bh.v &= (MAX_ROWID>>1); /* ensure doesn't go negative */
         }
-        u.bg.v++; /* ensure non-zero */
+        u.bh.v++; /* ensure non-zero */
       }
-      if( rc==SQLITE_OK && u.bg.res==0 ){
+      if( rc==SQLITE_OK && u.bh.res==0 ){
         rc = SQLITE_FULL;   /* IMP: R-38219-53002 */
         goto abort_due_to_error;
       }
-      assert( u.bg.v>0 );  /* EV: R-40812-03570 */
+      assert( u.bh.v>0 );  /* EV: R-40812-03570 */
     }
-    u.bg.pC->rowidIsValid = 0;
-    u.bg.pC->deferredMoveto = 0;
-    u.bg.pC->cacheStatus = CACHE_STALE;
+    u.bh.pC->rowidIsValid = 0;
+    u.bh.pC->deferredMoveto = 0;
+    u.bh.pC->cacheStatus = CACHE_STALE;
   }
-  pOut->u.i = u.bg.v;
+  pOut->u.i = u.bh.v;
   break;
 }
 
@@ -69789,7 +69552,7 @@ case OP_NewRowid: {           /* out2-prerelease */
 */
 case OP_Insert: 
 case OP_InsertInt: {
-#if 0  /* local variables moved into u.bh */
+#if 0  /* local variables moved into u.bi */
   Mem *pData;       /* MEM cell holding data for the record to be inserted */
   Mem *pKey;        /* MEM cell holding key  for the record */
   i64 iKey;         /* The integer ROWID or key for the record to be inserted */
@@ -69799,60 +69562,60 @@ case OP_InsertInt: {
   const char *zDb;  /* database name - used by the update hook */
   const char *zTbl; /* Table name - used by the opdate hook */
   int op;           /* Opcode for update hook: SQLITE_UPDATE or SQLITE_INSERT */
-#endif /* local variables moved into u.bh */
+#endif /* local variables moved into u.bi */
 
-  u.bh.pData = &aMem[pOp->p2];
+  u.bi.pData = &aMem[pOp->p2];
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  assert( memIsValid(u.bh.pData) );
-  u.bh.pC = p->apCsr[pOp->p1];
-  assert( u.bh.pC!=0 );
-  assert( u.bh.pC->pCursor!=0 );
-  assert( u.bh.pC->pseudoTableReg==0 );
-  assert( u.bh.pC->isTable );
-  REGISTER_TRACE(pOp->p2, u.bh.pData);
+  assert( memIsValid(u.bi.pData) );
+  u.bi.pC = p->apCsr[pOp->p1];
+  assert( u.bi.pC!=0 );
+  assert( u.bi.pC->pCursor!=0 );
+  assert( u.bi.pC->pseudoTableReg==0 );
+  assert( u.bi.pC->isTable );
+  REGISTER_TRACE(pOp->p2, u.bi.pData);
 
   if( pOp->opcode==OP_Insert ){
-    u.bh.pKey = &aMem[pOp->p3];
-    assert( u.bh.pKey->flags & MEM_Int );
-    assert( memIsValid(u.bh.pKey) );
-    REGISTER_TRACE(pOp->p3, u.bh.pKey);
-    u.bh.iKey = u.bh.pKey->u.i;
+    u.bi.pKey = &aMem[pOp->p3];
+    assert( u.bi.pKey->flags & MEM_Int );
+    assert( memIsValid(u.bi.pKey) );
+    REGISTER_TRACE(pOp->p3, u.bi.pKey);
+    u.bi.iKey = u.bi.pKey->u.i;
   }else{
     assert( pOp->opcode==OP_InsertInt );
-    u.bh.iKey = pOp->p3;
+    u.bi.iKey = pOp->p3;
   }
 
   if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++;
-  if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = lastRowid = u.bh.iKey;
-  if( u.bh.pData->flags & MEM_Null ){
-    u.bh.pData->z = 0;
-    u.bh.pData->n = 0;
+  if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = lastRowid = u.bi.iKey;
+  if( u.bi.pData->flags & MEM_Null ){
+    u.bi.pData->z = 0;
+    u.bi.pData->n = 0;
   }else{
-    assert( u.bh.pData->flags & (MEM_Blob|MEM_Str) );
+    assert( u.bi.pData->flags & (MEM_Blob|MEM_Str) );
   }
-  u.bh.seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? u.bh.pC->seekResult : 0);
-  if( u.bh.pData->flags & MEM_Zero ){
-    u.bh.nZero = u.bh.pData->u.nZero;
+  u.bi.seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? u.bi.pC->seekResult : 0);
+  if( u.bi.pData->flags & MEM_Zero ){
+    u.bi.nZero = u.bi.pData->u.nZero;
   }else{
-    u.bh.nZero = 0;
+    u.bi.nZero = 0;
   }
-  sqlite3BtreeSetCachedRowid(u.bh.pC->pCursor, 0);
-  rc = sqlite3BtreeInsert(u.bh.pC->pCursor, 0, u.bh.iKey,
-                          u.bh.pData->z, u.bh.pData->n, u.bh.nZero,
-                          pOp->p5 & OPFLAG_APPEND, u.bh.seekResult
+  sqlite3BtreeSetCachedRowid(u.bi.pC->pCursor, 0);
+  rc = sqlite3BtreeInsert(u.bi.pC->pCursor, 0, u.bi.iKey,
+                          u.bi.pData->z, u.bi.pData->n, u.bi.nZero,
+                          pOp->p5 & OPFLAG_APPEND, u.bi.seekResult
   );
-  u.bh.pC->rowidIsValid = 0;
-  u.bh.pC->deferredMoveto = 0;
-  u.bh.pC->cacheStatus = CACHE_STALE;
+  u.bi.pC->rowidIsValid = 0;
+  u.bi.pC->deferredMoveto = 0;
+  u.bi.pC->cacheStatus = CACHE_STALE;
 
   /* Invoke the update-hook if required. */
   if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
-    u.bh.zDb = db->aDb[u.bh.pC->iDb].zName;
-    u.bh.zTbl = pOp->p4.z;
-    u.bh.op = ((pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT);
-    assert( u.bh.pC->isTable );
-    db->xUpdateCallback(db->pUpdateArg, u.bh.op, u.bh.zDb, u.bh.zTbl, u.bh.iKey);
-    assert( u.bh.pC->iDb>=0 );
+    u.bi.zDb = db->aDb[u.bi.pC->iDb].zName;
+    u.bi.zTbl = pOp->p4.z;
+    u.bi.op = ((pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT);
+    assert( u.bi.pC->isTable );
+    db->xUpdateCallback(db->pUpdateArg, u.bi.op, u.bi.zDb, u.bi.zTbl, u.bi.iKey);
+    assert( u.bi.pC->iDb>=0 );
   }
   break;
 }
@@ -69878,47 +69641,47 @@ case OP_InsertInt: {
 ** using OP_NotFound prior to invoking this opcode.
 */
 case OP_Delete: {
-#if 0  /* local variables moved into u.bi */
+#if 0  /* local variables moved into u.bj */
   i64 iKey;
   VdbeCursor *pC;
-#endif /* local variables moved into u.bi */
+#endif /* local variables moved into u.bj */
 
-  u.bi.iKey = 0;
+  u.bj.iKey = 0;
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bi.pC = p->apCsr[pOp->p1];
-  assert( u.bi.pC!=0 );
-  assert( u.bi.pC->pCursor!=0 );  /* Only valid for real tables, no pseudotables */
+  u.bj.pC = p->apCsr[pOp->p1];
+  assert( u.bj.pC!=0 );
+  assert( u.bj.pC->pCursor!=0 );  /* Only valid for real tables, no pseudotables */
 
-  /* If the update-hook will be invoked, set u.bi.iKey to the rowid of the
+  /* If the update-hook will be invoked, set u.bj.iKey to the rowid of the
   ** row being deleted.
   */
   if( db->xUpdateCallback && pOp->p4.z ){
-    assert( u.bi.pC->isTable );
-    assert( u.bi.pC->rowidIsValid );  /* lastRowid set by previous OP_NotFound */
-    u.bi.iKey = u.bi.pC->lastRowid;
+    assert( u.bj.pC->isTable );
+    assert( u.bj.pC->rowidIsValid );  /* lastRowid set by previous OP_NotFound */
+    u.bj.iKey = u.bj.pC->lastRowid;
   }
 
   /* The OP_Delete opcode always follows an OP_NotExists or OP_Last or
   ** OP_Column on the same table without any intervening operations that
-  ** might move or invalidate the cursor.  Hence cursor u.bi.pC is always pointing
+  ** might move or invalidate the cursor.  Hence cursor u.bj.pC is always pointing
   ** to the row to be deleted and the sqlite3VdbeCursorMoveto() operation
   ** below is always a no-op and cannot fail.  We will run it anyhow, though,
   ** to guard against future changes to the code generator.
   **/
-  assert( u.bi.pC->deferredMoveto==0 );
-  rc = sqlite3VdbeCursorMoveto(u.bi.pC);
+  assert( u.bj.pC->deferredMoveto==0 );
+  rc = sqlite3VdbeCursorMoveto(u.bj.pC);
   if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;
 
-  sqlite3BtreeSetCachedRowid(u.bi.pC->pCursor, 0);
-  rc = sqlite3BtreeDelete(u.bi.pC->pCursor);
-  u.bi.pC->cacheStatus = CACHE_STALE;
+  sqlite3BtreeSetCachedRowid(u.bj.pC->pCursor, 0);
+  rc = sqlite3BtreeDelete(u.bj.pC->pCursor);
+  u.bj.pC->cacheStatus = CACHE_STALE;
 
   /* Invoke the update-hook if required. */
   if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
-    const char *zDb = db->aDb[u.bi.pC->iDb].zName;
+    const char *zDb = db->aDb[u.bj.pC->iDb].zName;
     const char *zTbl = pOp->p4.z;
-    db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, zDb, zTbl, u.bi.iKey);
-    assert( u.bi.pC->iDb>=0 );
+    db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, zDb, zTbl, u.bj.iKey);
+    assert( u.bj.pC->iDb>=0 );
   }
   if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
   break;
@@ -69944,16 +69707,16 @@ case OP_ResetCount: {
 ** fall through to the next instruction. Otherwise, jump to instruction P2.
 */
 case OP_SorterCompare: {
-#if 0  /* local variables moved into u.bj */
+#if 0  /* local variables moved into u.bk */
   VdbeCursor *pC;
   int res;
-#endif /* local variables moved into u.bj */
+#endif /* local variables moved into u.bk */
 
-  u.bj.pC = p->apCsr[pOp->p1];
-  assert( isSorter(u.bj.pC) );
+  u.bk.pC = p->apCsr[pOp->p1];
+  assert( isSorter(u.bk.pC) );
   pIn3 = &aMem[pOp->p3];
-  rc = sqlite3VdbeSorterCompare(u.bj.pC, pIn3, &u.bj.res);
-  if( u.bj.res ){
+  rc = sqlite3VdbeSorterCompare(u.bk.pC, pIn3, &u.bk.res);
+  if( u.bk.res ){
     pc = pOp->p2-1;
   }
   break;
@@ -69964,18 +69727,14 @@ case OP_SorterCompare: {
 ** Write into register P2 the current sorter data for sorter cursor P1.
 */
 case OP_SorterData: {
-#if 0  /* local variables moved into u.bk */
+#if 0  /* local variables moved into u.bl */
   VdbeCursor *pC;
-#endif /* local variables moved into u.bk */
-#ifndef SQLITE_OMIT_MERGE_SORT
+#endif /* local variables moved into u.bl */
+
   pOut = &aMem[pOp->p2];
-  u.bk.pC = p->apCsr[pOp->p1];
-  assert( u.bk.pC->isSorter );
-  rc = sqlite3VdbeSorterRowkey(u.bk.pC, pOut);
-#else
-  pOp->opcode = OP_RowKey;
-  pc--;
-#endif
+  u.bl.pC = p->apCsr[pOp->p1];
+  assert( u.bl.pC->isSorter );
+  rc = sqlite3VdbeSorterRowkey(u.bl.pC, pOut);
   break;
 }
 
@@ -70001,62 +69760,62 @@ case OP_SorterData: {
 */
 case OP_RowKey:
 case OP_RowData: {
-#if 0  /* local variables moved into u.bl */
+#if 0  /* local variables moved into u.bm */
   VdbeCursor *pC;
   BtCursor *pCrsr;
   u32 n;
   i64 n64;
-#endif /* local variables moved into u.bl */
+#endif /* local variables moved into u.bm */
 
   pOut = &aMem[pOp->p2];
   memAboutToChange(p, pOut);
 
   /* Note that RowKey and RowData are really exactly the same instruction */
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bl.pC = p->apCsr[pOp->p1];
-  assert( u.bl.pC->isSorter==0 );
-  assert( u.bl.pC->isTable || pOp->opcode!=OP_RowData );
-  assert( u.bl.pC->isIndex || pOp->opcode==OP_RowData );
-  assert( u.bl.pC!=0 );
-  assert( u.bl.pC->nullRow==0 );
-  assert( u.bl.pC->pseudoTableReg==0 );
-  assert( u.bl.pC->pCursor!=0 );
-  u.bl.pCrsr = u.bl.pC->pCursor;
-  assert( sqlite3BtreeCursorIsValid(u.bl.pCrsr) );
+  u.bm.pC = p->apCsr[pOp->p1];
+  assert( u.bm.pC->isSorter==0 );
+  assert( u.bm.pC->isTable || pOp->opcode!=OP_RowData );
+  assert( u.bm.pC->isIndex || pOp->opcode==OP_RowData );
+  assert( u.bm.pC!=0 );
+  assert( u.bm.pC->nullRow==0 );
+  assert( u.bm.pC->pseudoTableReg==0 );
+  assert( u.bm.pC->pCursor!=0 );
+  u.bm.pCrsr = u.bm.pC->pCursor;
+  assert( sqlite3BtreeCursorIsValid(u.bm.pCrsr) );
 
   /* The OP_RowKey and OP_RowData opcodes always follow OP_NotExists or
   ** OP_Rewind/Op_Next with no intervening instructions that might invalidate
   ** the cursor.  Hence the following sqlite3VdbeCursorMoveto() call is always
   ** a no-op and can never fail.  But we leave it in place as a safety.
   */
-  assert( u.bl.pC->deferredMoveto==0 );
-  rc = sqlite3VdbeCursorMoveto(u.bl.pC);
+  assert( u.bm.pC->deferredMoveto==0 );
+  rc = sqlite3VdbeCursorMoveto(u.bm.pC);
   if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error;
 
-  if( u.bl.pC->isIndex ){
-    assert( !u.bl.pC->isTable );
-    VVA_ONLY(rc =) sqlite3BtreeKeySize(u.bl.pCrsr, &u.bl.n64);
+  if( u.bm.pC->isIndex ){
+    assert( !u.bm.pC->isTable );
+    VVA_ONLY(rc =) sqlite3BtreeKeySize(u.bm.pCrsr, &u.bm.n64);
     assert( rc==SQLITE_OK );    /* True because of CursorMoveto() call above */
-    if( u.bl.n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
+    if( u.bm.n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
       goto too_big;
     }
-    u.bl.n = (u32)u.bl.n64;
+    u.bm.n = (u32)u.bm.n64;
   }else{
-    VVA_ONLY(rc =) sqlite3BtreeDataSize(u.bl.pCrsr, &u.bl.n);
+    VVA_ONLY(rc =) sqlite3BtreeDataSize(u.bm.pCrsr, &u.bm.n);
     assert( rc==SQLITE_OK );    /* DataSize() cannot fail */
-    if( u.bl.n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
+    if( u.bm.n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
       goto too_big;
     }
   }
-  if( sqlite3VdbeMemGrow(pOut, u.bl.n, 0) ){
+  if( sqlite3VdbeMemGrow(pOut, u.bm.n, 0) ){
     goto no_mem;
   }
-  pOut->n = u.bl.n;
+  pOut->n = u.bm.n;
   MemSetTypeFlag(pOut, MEM_Blob);
-  if( u.bl.pC->isIndex ){
-    rc = sqlite3BtreeKey(u.bl.pCrsr, 0, u.bl.n, pOut->z);
+  if( u.bm.pC->isIndex ){
+    rc = sqlite3BtreeKey(u.bm.pCrsr, 0, u.bm.n, pOut->z);
   }else{
-    rc = sqlite3BtreeData(u.bl.pCrsr, 0, u.bl.n, pOut->z);
+    rc = sqlite3BtreeData(u.bm.pCrsr, 0, u.bm.n, pOut->z);
   }
   pOut->enc = SQLITE_UTF8;  /* In case the blob is ever cast to text */
   UPDATE_MAX_BLOBSIZE(pOut);
@@ -70073,42 +69832,42 @@ case OP_RowData: {
 ** one opcode now works for both table types.
 */
 case OP_Rowid: {                 /* out2-prerelease */
-#if 0  /* local variables moved into u.bm */
+#if 0  /* local variables moved into u.bn */
   VdbeCursor *pC;
   i64 v;
   sqlite3_vtab *pVtab;
   const sqlite3_module *pModule;
-#endif /* local variables moved into u.bm */
+#endif /* local variables moved into u.bn */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bm.pC = p->apCsr[pOp->p1];
-  assert( u.bm.pC!=0 );
-  assert( u.bm.pC->pseudoTableReg==0 );
-  if( u.bm.pC->nullRow ){
+  u.bn.pC = p->apCsr[pOp->p1];
+  assert( u.bn.pC!=0 );
+  assert( u.bn.pC->pseudoTableReg==0 || u.bn.pC->nullRow );
+  if( u.bn.pC->nullRow ){
     pOut->flags = MEM_Null;
     break;
-  }else if( u.bm.pC->deferredMoveto ){
-    u.bm.v = u.bm.pC->movetoTarget;
+  }else if( u.bn.pC->deferredMoveto ){
+    u.bn.v = u.bn.pC->movetoTarget;
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  }else if( u.bm.pC->pVtabCursor ){
-    u.bm.pVtab = u.bm.pC->pVtabCursor->pVtab;
-    u.bm.pModule = u.bm.pVtab->pModule;
-    assert( u.bm.pModule->xRowid );
-    rc = u.bm.pModule->xRowid(u.bm.pC->pVtabCursor, &u.bm.v);
-    importVtabErrMsg(p, u.bm.pVtab);
+  }else if( u.bn.pC->pVtabCursor ){
+    u.bn.pVtab = u.bn.pC->pVtabCursor->pVtab;
+    u.bn.pModule = u.bn.pVtab->pModule;
+    assert( u.bn.pModule->xRowid );
+    rc = u.bn.pModule->xRowid(u.bn.pC->pVtabCursor, &u.bn.v);
+    sqlite3VtabImportErrmsg(p, u.bn.pVtab);
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
   }else{
-    assert( u.bm.pC->pCursor!=0 );
-    rc = sqlite3VdbeCursorMoveto(u.bm.pC);
+    assert( u.bn.pC->pCursor!=0 );
+    rc = sqlite3VdbeCursorMoveto(u.bn.pC);
     if( rc ) goto abort_due_to_error;
-    if( u.bm.pC->rowidIsValid ){
-      u.bm.v = u.bm.pC->lastRowid;
+    if( u.bn.pC->rowidIsValid ){
+      u.bn.v = u.bn.pC->lastRowid;
     }else{
-      rc = sqlite3BtreeKeySize(u.bm.pC->pCursor, &u.bm.v);
+      rc = sqlite3BtreeKeySize(u.bn.pC->pCursor, &u.bn.v);
       assert( rc==SQLITE_OK );  /* Always so because of CursorMoveto() above */
     }
   }
-  pOut->u.i = u.bm.v;
+  pOut->u.i = u.bn.v;
   break;
 }
 
@@ -70119,18 +69878,18 @@ case OP_Rowid: {                 /* out2-prerelease */
 ** write a NULL.
 */
 case OP_NullRow: {
-#if 0  /* local variables moved into u.bn */
+#if 0  /* local variables moved into u.bo */
   VdbeCursor *pC;
-#endif /* local variables moved into u.bn */
+#endif /* local variables moved into u.bo */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bn.pC = p->apCsr[pOp->p1];
-  assert( u.bn.pC!=0 );
-  u.bn.pC->nullRow = 1;
-  u.bn.pC->rowidIsValid = 0;
-  assert( u.bn.pC->pCursor || u.bn.pC->pVtabCursor );
-  if( u.bn.pC->pCursor ){
-    sqlite3BtreeClearCursor(u.bn.pC->pCursor);
+  u.bo.pC = p->apCsr[pOp->p1];
+  assert( u.bo.pC!=0 );
+  u.bo.pC->nullRow = 1;
+  u.bo.pC->rowidIsValid = 0;
+  assert( u.bo.pC->pCursor || u.bo.pC->pVtabCursor );
+  if( u.bo.pC->pCursor ){
+    sqlite3BtreeClearCursor(u.bo.pC->pCursor);
   }
   break;
 }
@@ -70144,25 +69903,25 @@ case OP_NullRow: {
 ** to the following instruction.
 */
 case OP_Last: {        /* jump */
-#if 0  /* local variables moved into u.bo */
+#if 0  /* local variables moved into u.bp */
   VdbeCursor *pC;
   BtCursor *pCrsr;
   int res;
-#endif /* local variables moved into u.bo */
+#endif /* local variables moved into u.bp */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bo.pC = p->apCsr[pOp->p1];
-  assert( u.bo.pC!=0 );
-  u.bo.pCrsr = u.bo.pC->pCursor;
-  u.bo.res = 0;
-  if( ALWAYS(u.bo.pCrsr!=0) ){
-    rc = sqlite3BtreeLast(u.bo.pCrsr, &u.bo.res);
+  u.bp.pC = p->apCsr[pOp->p1];
+  assert( u.bp.pC!=0 );
+  u.bp.pCrsr = u.bp.pC->pCursor;
+  u.bp.res = 0;
+  if( ALWAYS(u.bp.pCrsr!=0) ){
+    rc = sqlite3BtreeLast(u.bp.pCrsr, &u.bp.res);
   }
-  u.bo.pC->nullRow = (u8)u.bo.res;
-  u.bo.pC->deferredMoveto = 0;
-  u.bo.pC->rowidIsValid = 0;
-  u.bo.pC->cacheStatus = CACHE_STALE;
-  if( pOp->p2>0 && u.bo.res ){
+  u.bp.pC->nullRow = (u8)u.bp.res;
+  u.bp.pC->deferredMoveto = 0;
+  u.bp.pC->rowidIsValid = 0;
+  u.bp.pC->cacheStatus = CACHE_STALE;
+  if( pOp->p2>0 && u.bp.res ){
     pc = pOp->p2 - 1;
   }
   break;
@@ -70182,15 +69941,12 @@ case OP_Last: {        /* jump */
 ** correctly optimizing out sorts.
 */
 case OP_SorterSort:    /* jump */
-#ifdef SQLITE_OMIT_MERGE_SORT
-  pOp->opcode = OP_Sort;
-#endif
 case OP_Sort: {        /* jump */
 #ifdef SQLITE_TEST
   sqlite3_sort_count++;
   sqlite3_search_count--;
 #endif
-  p->aCounter[SQLITE_STMTSTATUS_SORT-1]++;
+  p->aCounter[SQLITE_STMTSTATUS_SORT]++;
   /* Fall through into OP_Rewind */
 }
 /* Opcode: Rewind P1 P2 * * *
@@ -70202,31 +69958,31 @@ case OP_Sort: {        /* jump */
 ** to the following instruction.
 */
 case OP_Rewind: {        /* jump */
-#if 0  /* local variables moved into u.bp */
+#if 0  /* local variables moved into u.bq */
   VdbeCursor *pC;
   BtCursor *pCrsr;
   int res;
-#endif /* local variables moved into u.bp */
+#endif /* local variables moved into u.bq */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bp.pC = p->apCsr[pOp->p1];
-  assert( u.bp.pC!=0 );
-  assert( u.bp.pC->isSorter==(pOp->opcode==OP_SorterSort) );
-  u.bp.res = 1;
-  if( isSorter(u.bp.pC) ){
-    rc = sqlite3VdbeSorterRewind(db, u.bp.pC, &u.bp.res);
+  u.bq.pC = p->apCsr[pOp->p1];
+  assert( u.bq.pC!=0 );
+  assert( u.bq.pC->isSorter==(pOp->opcode==OP_SorterSort) );
+  u.bq.res = 1;
+  if( isSorter(u.bq.pC) ){
+    rc = sqlite3VdbeSorterRewind(db, u.bq.pC, &u.bq.res);
   }else{
-    u.bp.pCrsr = u.bp.pC->pCursor;
-    assert( u.bp.pCrsr );
-    rc = sqlite3BtreeFirst(u.bp.pCrsr, &u.bp.res);
-    u.bp.pC->atFirst = u.bp.res==0 ?1:0;
-    u.bp.pC->deferredMoveto = 0;
-    u.bp.pC->cacheStatus = CACHE_STALE;
-    u.bp.pC->rowidIsValid = 0;
+    u.bq.pCrsr = u.bq.pC->pCursor;
+    assert( u.bq.pCrsr );
+    rc = sqlite3BtreeFirst(u.bq.pCrsr, &u.bq.res);
+    u.bq.pC->atFirst = u.bq.res==0 ?1:0;
+    u.bq.pC->deferredMoveto = 0;
+    u.bq.pC->cacheStatus = CACHE_STALE;
+    u.bq.pC->rowidIsValid = 0;
   }
-  u.bp.pC->nullRow = (u8)u.bp.res;
+  u.bq.pC->nullRow = (u8)u.bq.res;
   assert( pOp->p2>0 && pOp->p2<p->nOp );
-  if( u.bp.res ){
+  if( u.bq.res ){
     pc = pOp->p2 - 1;
   }
   break;
@@ -70265,46 +70021,42 @@ case OP_Rewind: {        /* jump */
 ** number P5-1 in the prepared statement is incremented.
 */
 case OP_SorterNext:    /* jump */
-#ifdef SQLITE_OMIT_MERGE_SORT
-  pOp->opcode = OP_Next;
-#endif
 case OP_Prev:          /* jump */
 case OP_Next: {        /* jump */
-#if 0  /* local variables moved into u.bq */
+#if 0  /* local variables moved into u.br */
   VdbeCursor *pC;
   int res;
-#endif /* local variables moved into u.bq */
+#endif /* local variables moved into u.br */
 
-  CHECK_FOR_INTERRUPT;
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  assert( pOp->p5<=ArraySize(p->aCounter) );
-  u.bq.pC = p->apCsr[pOp->p1];
-  if( u.bq.pC==0 ){
+  assert( pOp->p5<ArraySize(p->aCounter) );
+  u.br.pC = p->apCsr[pOp->p1];
+  if( u.br.pC==0 ){
     break;  /* See ticket #2273 */
   }
-  assert( u.bq.pC->isSorter==(pOp->opcode==OP_SorterNext) );
-  if( isSorter(u.bq.pC) ){
+  assert( u.br.pC->isSorter==(pOp->opcode==OP_SorterNext) );
+  if( isSorter(u.br.pC) ){
     assert( pOp->opcode==OP_SorterNext );
-    rc = sqlite3VdbeSorterNext(db, u.bq.pC, &u.bq.res);
+    rc = sqlite3VdbeSorterNext(db, u.br.pC, &u.br.res);
   }else{
-    u.bq.res = 1;
-    assert( u.bq.pC->deferredMoveto==0 );
-    assert( u.bq.pC->pCursor );
+    /* u.br.res = 1; // Always initialized by the xAdvance() call */
+    assert( u.br.pC->deferredMoveto==0 );
+    assert( u.br.pC->pCursor );
     assert( pOp->opcode!=OP_Next || pOp->p4.xAdvance==sqlite3BtreeNext );
     assert( pOp->opcode!=OP_Prev || pOp->p4.xAdvance==sqlite3BtreePrevious );
-    rc = pOp->p4.xAdvance(u.bq.pC->pCursor, &u.bq.res);
+    rc = pOp->p4.xAdvance(u.br.pC->pCursor, &u.br.res);
   }
-  u.bq.pC->nullRow = (u8)u.bq.res;
-  u.bq.pC->cacheStatus = CACHE_STALE;
-  if( u.bq.res==0 ){
+  u.br.pC->nullRow = (u8)u.br.res;
+  u.br.pC->cacheStatus = CACHE_STALE;
+  if( u.br.res==0 ){
     pc = pOp->p2 - 1;
-    if( pOp->p5 ) p->aCounter[pOp->p5-1]++;
+    p->aCounter[pOp->p5]++;
 #ifdef SQLITE_TEST
     sqlite3_search_count++;
 #endif
   }
-  u.bq.pC->rowidIsValid = 0;
-  break;
+  u.br.pC->rowidIsValid = 0;
+  goto check_for_interrupt;
 }
 
 /* Opcode: IdxInsert P1 P2 P3 * P5
@@ -70320,38 +70072,35 @@ case OP_Next: {        /* jump */
 ** for tables is OP_Insert.
 */
 case OP_SorterInsert:       /* in2 */
-#ifdef SQLITE_OMIT_MERGE_SORT
-  pOp->opcode = OP_IdxInsert;
-#endif
 case OP_IdxInsert: {        /* in2 */
-#if 0  /* local variables moved into u.br */
+#if 0  /* local variables moved into u.bs */
   VdbeCursor *pC;
   BtCursor *pCrsr;
   int nKey;
   const char *zKey;
-#endif /* local variables moved into u.br */
+#endif /* local variables moved into u.bs */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.br.pC = p->apCsr[pOp->p1];
-  assert( u.br.pC!=0 );
-  assert( u.br.pC->isSorter==(pOp->opcode==OP_SorterInsert) );
+  u.bs.pC = p->apCsr[pOp->p1];
+  assert( u.bs.pC!=0 );
+  assert( u.bs.pC->isSorter==(pOp->opcode==OP_SorterInsert) );
   pIn2 = &aMem[pOp->p2];
   assert( pIn2->flags & MEM_Blob );
-  u.br.pCrsr = u.br.pC->pCursor;
-  if( ALWAYS(u.br.pCrsr!=0) ){
-    assert( u.br.pC->isTable==0 );
+  u.bs.pCrsr = u.bs.pC->pCursor;
+  if( ALWAYS(u.bs.pCrsr!=0) ){
+    assert( u.bs.pC->isTable==0 );
     rc = ExpandBlob(pIn2);
     if( rc==SQLITE_OK ){
-      if( isSorter(u.br.pC) ){
-        rc = sqlite3VdbeSorterWrite(db, u.br.pC, pIn2);
+      if( isSorter(u.bs.pC) ){
+        rc = sqlite3VdbeSorterWrite(db, u.bs.pC, pIn2);
       }else{
-        u.br.nKey = pIn2->n;
-        u.br.zKey = pIn2->z;
-        rc = sqlite3BtreeInsert(u.br.pCrsr, u.br.zKey, u.br.nKey, "", 0, 0, pOp->p3,
-            ((pOp->p5 & OPFLAG_USESEEKRESULT) ? u.br.pC->seekResult : 0)
+        u.bs.nKey = pIn2->n;
+        u.bs.zKey = pIn2->z;
+        rc = sqlite3BtreeInsert(u.bs.pCrsr, u.bs.zKey, u.bs.nKey, "", 0, 0, pOp->p3,
+            ((pOp->p5 & OPFLAG_USESEEKRESULT) ? u.bs.pC->seekResult : 0)
             );
-        assert( u.br.pC->deferredMoveto==0 );
-        u.br.pC->cacheStatus = CACHE_STALE;
+        assert( u.bs.pC->deferredMoveto==0 );
+        u.bs.pC->cacheStatus = CACHE_STALE;
       }
     }
   }
@@ -70365,33 +70114,33 @@ case OP_IdxInsert: {        /* in2 */
 ** index opened by cursor P1.
 */
 case OP_IdxDelete: {
-#if 0  /* local variables moved into u.bs */
+#if 0  /* local variables moved into u.bt */
   VdbeCursor *pC;
   BtCursor *pCrsr;
   int res;
   UnpackedRecord r;
-#endif /* local variables moved into u.bs */
+#endif /* local variables moved into u.bt */
 
   assert( pOp->p3>0 );
   assert( pOp->p2>0 && pOp->p2+pOp->p3<=p->nMem+1 );
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bs.pC = p->apCsr[pOp->p1];
-  assert( u.bs.pC!=0 );
-  u.bs.pCrsr = u.bs.pC->pCursor;
-  if( ALWAYS(u.bs.pCrsr!=0) ){
-    u.bs.r.pKeyInfo = u.bs.pC->pKeyInfo;
-    u.bs.r.nField = (u16)pOp->p3;
-    u.bs.r.flags = 0;
-    u.bs.r.aMem = &aMem[pOp->p2];
+  u.bt.pC = p->apCsr[pOp->p1];
+  assert( u.bt.pC!=0 );
+  u.bt.pCrsr = u.bt.pC->pCursor;
+  if( ALWAYS(u.bt.pCrsr!=0) ){
+    u.bt.r.pKeyInfo = u.bt.pC->pKeyInfo;
+    u.bt.r.nField = (u16)pOp->p3;
+    u.bt.r.flags = 0;
+    u.bt.r.aMem = &aMem[pOp->p2];
 #ifdef SQLITE_DEBUG
-    { int i; for(i=0; i<u.bs.r.nField; i++) assert( memIsValid(&u.bs.r.aMem[i]) ); }
+    { int i; for(i=0; i<u.bt.r.nField; i++) assert( memIsValid(&u.bt.r.aMem[i]) ); }
 #endif
-    rc = sqlite3BtreeMovetoUnpacked(u.bs.pCrsr, &u.bs.r, 0, 0, &u.bs.res);
-    if( rc==SQLITE_OK && u.bs.res==0 ){
-      rc = sqlite3BtreeDelete(u.bs.pCrsr);
+    rc = sqlite3BtreeMovetoUnpacked(u.bt.pCrsr, &u.bt.r, 0, 0, &u.bt.res);
+    if( rc==SQLITE_OK && u.bt.res==0 ){
+      rc = sqlite3BtreeDelete(u.bt.pCrsr);
     }
-    assert( u.bs.pC->deferredMoveto==0 );
-    u.bs.pC->cacheStatus = CACHE_STALE;
+    assert( u.bt.pC->deferredMoveto==0 );
+    u.bt.pC->cacheStatus = CACHE_STALE;
   }
   break;
 }
@@ -70405,28 +70154,28 @@ case OP_IdxDelete: {
 ** See also: Rowid, MakeRecord.
 */
 case OP_IdxRowid: {              /* out2-prerelease */
-#if 0  /* local variables moved into u.bt */
+#if 0  /* local variables moved into u.bu */
   BtCursor *pCrsr;
   VdbeCursor *pC;
   i64 rowid;
-#endif /* local variables moved into u.bt */
+#endif /* local variables moved into u.bu */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bt.pC = p->apCsr[pOp->p1];
-  assert( u.bt.pC!=0 );
-  u.bt.pCrsr = u.bt.pC->pCursor;
+  u.bu.pC = p->apCsr[pOp->p1];
+  assert( u.bu.pC!=0 );
+  u.bu.pCrsr = u.bu.pC->pCursor;
   pOut->flags = MEM_Null;
-  if( ALWAYS(u.bt.pCrsr!=0) ){
-    rc = sqlite3VdbeCursorMoveto(u.bt.pC);
+  if( ALWAYS(u.bu.pCrsr!=0) ){
+    rc = sqlite3VdbeCursorMoveto(u.bu.pC);
     if( NEVER(rc) ) goto abort_due_to_error;
-    assert( u.bt.pC->deferredMoveto==0 );
-    assert( u.bt.pC->isTable==0 );
-    if( !u.bt.pC->nullRow ){
-      rc = sqlite3VdbeIdxRowid(db, u.bt.pCrsr, &u.bt.rowid);
+    assert( u.bu.pC->deferredMoveto==0 );
+    assert( u.bu.pC->isTable==0 );
+    if( !u.bu.pC->nullRow ){
+      rc = sqlite3VdbeIdxRowid(db, u.bu.pCrsr, &u.bu.rowid);
       if( rc!=SQLITE_OK ){
         goto abort_due_to_error;
       }
-      pOut->u.i = u.bt.rowid;
+      pOut->u.i = u.bu.rowid;
       pOut->flags = MEM_Int;
     }
   }
@@ -70461,39 +70210,39 @@ case OP_IdxRowid: {              /* out2-prerelease */
 */
 case OP_IdxLT:          /* jump */
 case OP_IdxGE: {        /* jump */
-#if 0  /* local variables moved into u.bu */
+#if 0  /* local variables moved into u.bv */
   VdbeCursor *pC;
   int res;
   UnpackedRecord r;
-#endif /* local variables moved into u.bu */
+#endif /* local variables moved into u.bv */
 
   assert( pOp->p1>=0 && pOp->p1<p->nCursor );
-  u.bu.pC = p->apCsr[pOp->p1];
-  assert( u.bu.pC!=0 );
-  assert( u.bu.pC->isOrdered );
-  if( ALWAYS(u.bu.pC->pCursor!=0) ){
-    assert( u.bu.pC->deferredMoveto==0 );
+  u.bv.pC = p->apCsr[pOp->p1];
+  assert( u.bv.pC!=0 );
+  assert( u.bv.pC->isOrdered );
+  if( ALWAYS(u.bv.pC->pCursor!=0) ){
+    assert( u.bv.pC->deferredMoveto==0 );
     assert( pOp->p5==0 || pOp->p5==1 );
     assert( pOp->p4type==P4_INT32 );
-    u.bu.r.pKeyInfo = u.bu.pC->pKeyInfo;
-    u.bu.r.nField = (u16)pOp->p4.i;
+    u.bv.r.pKeyInfo = u.bv.pC->pKeyInfo;
+    u.bv.r.nField = (u16)pOp->p4.i;
     if( pOp->p5 ){
-      u.bu.r.flags = UNPACKED_INCRKEY | UNPACKED_PREFIX_MATCH;
+      u.bv.r.flags = UNPACKED_INCRKEY | UNPACKED_PREFIX_MATCH;
     }else{
-      u.bu.r.flags = UNPACKED_PREFIX_MATCH;
+      u.bv.r.flags = UNPACKED_PREFIX_MATCH;
     }
-    u.bu.r.aMem = &aMem[pOp->p3];
+    u.bv.r.aMem = &aMem[pOp->p3];
 #ifdef SQLITE_DEBUG
-    { int i; for(i=0; i<u.bu.r.nField; i++) assert( memIsValid(&u.bu.r.aMem[i]) ); }
+    { int i; for(i=0; i<u.bv.r.nField; i++) assert( memIsValid(&u.bv.r.aMem[i]) ); }
 #endif
-    rc = sqlite3VdbeIdxKeyCompare(u.bu.pC, &u.bu.r, &u.bu.res);
+    rc = sqlite3VdbeIdxKeyCompare(u.bv.pC, &u.bv.r, &u.bv.res);
     if( pOp->opcode==OP_IdxLT ){
-      u.bu.res = -u.bu.res;
+      u.bv.res = -u.bv.res;
     }else{
       assert( pOp->opcode==OP_IdxGE );
-      u.bu.res++;
+      u.bv.res++;
     }
-    if( u.bu.res>0 ){
+    if( u.bv.res>0 ){
       pc = pOp->p2 - 1 ;
     }
   }
@@ -70521,39 +70270,43 @@ case OP_IdxGE: {        /* jump */
 ** See also: Clear
 */
 case OP_Destroy: {     /* out2-prerelease */
-#if 0  /* local variables moved into u.bv */
+#if 0  /* local variables moved into u.bw */
   int iMoved;
   int iCnt;
   Vdbe *pVdbe;
   int iDb;
-#endif /* local variables moved into u.bv */
+#endif /* local variables moved into u.bw */
+
+  assert( p->readOnly==0 );
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  u.bv.iCnt = 0;
-  for(u.bv.pVdbe=db->pVdbe; u.bv.pVdbe; u.bv.pVdbe = u.bv.pVdbe->pNext){
-    if( u.bv.pVdbe->magic==VDBE_MAGIC_RUN && u.bv.pVdbe->inVtabMethod<2 && u.bv.pVdbe->pc>=0 ){
-      u.bv.iCnt++;
+  u.bw.iCnt = 0;
+  for(u.bw.pVdbe=db->pVdbe; u.bw.pVdbe; u.bw.pVdbe = u.bw.pVdbe->pNext){
+    if( u.bw.pVdbe->magic==VDBE_MAGIC_RUN && u.bw.pVdbe->bIsReader
+     && u.bw.pVdbe->inVtabMethod<2 && u.bw.pVdbe->pc>=0
+    ){
+      u.bw.iCnt++;
     }
   }
 #else
-  u.bv.iCnt = db->activeVdbeCnt;
+  u.bw.iCnt = db->nVdbeRead;
 #endif
   pOut->flags = MEM_Null;
-  if( u.bv.iCnt>1 ){
+  if( u.bw.iCnt>1 ){
     rc = SQLITE_LOCKED;
     p->errorAction = OE_Abort;
   }else{
-    u.bv.iDb = pOp->p3;
-    assert( u.bv.iCnt==1 );
-    assert( (p->btreeMask & (((yDbMask)1)<<u.bv.iDb))!=0 );
-    rc = sqlite3BtreeDropTable(db->aDb[u.bv.iDb].pBt, pOp->p1, &u.bv.iMoved);
+    u.bw.iDb = pOp->p3;
+    assert( u.bw.iCnt==1 );
+    assert( (p->btreeMask & (((yDbMask)1)<<u.bw.iDb))!=0 );
+    rc = sqlite3BtreeDropTable(db->aDb[u.bw.iDb].pBt, pOp->p1, &u.bw.iMoved);
     pOut->flags = MEM_Int;
-    pOut->u.i = u.bv.iMoved;
+    pOut->u.i = u.bw.iMoved;
 #ifndef SQLITE_OMIT_AUTOVACUUM
-    if( rc==SQLITE_OK && u.bv.iMoved!=0 ){
-      sqlite3RootPageMoved(db, u.bv.iDb, u.bv.iMoved, pOp->p1);
+    if( rc==SQLITE_OK && u.bw.iMoved!=0 ){
+      sqlite3RootPageMoved(db, u.bw.iDb, u.bw.iMoved, pOp->p1);
       /* All OP_Destroy operations occur on the same btree */
-      assert( resetSchemaOnFault==0 || resetSchemaOnFault==u.bv.iDb+1 );
-      resetSchemaOnFault = u.bv.iDb+1;
+      assert( resetSchemaOnFault==0 || resetSchemaOnFault==u.bw.iDb+1 );
+      resetSchemaOnFault = u.bw.iDb+1;
     }
 #endif
   }
@@ -70579,21 +70332,22 @@ case OP_Destroy: {     /* out2-prerelease */
 ** See also: Destroy
 */
 case OP_Clear: {
-#if 0  /* local variables moved into u.bw */
+#if 0  /* local variables moved into u.bx */
   int nChange;
-#endif /* local variables moved into u.bw */
+#endif /* local variables moved into u.bx */
 
-  u.bw.nChange = 0;
+  u.bx.nChange = 0;
+  assert( p->readOnly==0 );
   assert( (p->btreeMask & (((yDbMask)1)<<pOp->p2))!=0 );
   rc = sqlite3BtreeClearTable(
-      db->aDb[pOp->p2].pBt, pOp->p1, (pOp->p3 ? &u.bw.nChange : 0)
+      db->aDb[pOp->p2].pBt, pOp->p1, (pOp->p3 ? &u.bx.nChange : 0)
   );
   if( pOp->p3 ){
-    p->nChange += u.bw.nChange;
+    p->nChange += u.bx.nChange;
     if( pOp->p3>0 ){
       assert( memIsValid(&aMem[pOp->p3]) );
       memAboutToChange(p, &aMem[pOp->p3]);
-      aMem[pOp->p3].u.i += u.bw.nChange;
+      aMem[pOp->p3].u.i += u.bx.nChange;
     }
   }
   break;
@@ -70623,25 +70377,26 @@ case OP_Clear: {
 */
 case OP_CreateIndex:            /* out2-prerelease */
 case OP_CreateTable: {          /* out2-prerelease */
-#if 0  /* local variables moved into u.bx */
+#if 0  /* local variables moved into u.by */
   int pgno;
   int flags;
   Db *pDb;
-#endif /* local variables moved into u.bx */
+#endif /* local variables moved into u.by */
 
-  u.bx.pgno = 0;
+  u.by.pgno = 0;
   assert( pOp->p1>=0 && pOp->p1<db->nDb );
   assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
-  u.bx.pDb = &db->aDb[pOp->p1];
-  assert( u.bx.pDb->pBt!=0 );
+  assert( p->readOnly==0 );
+  u.by.pDb = &db->aDb[pOp->p1];
+  assert( u.by.pDb->pBt!=0 );
   if( pOp->opcode==OP_CreateTable ){
-    /* u.bx.flags = BTREE_INTKEY; */
-    u.bx.flags = BTREE_INTKEY;
+    /* u.by.flags = BTREE_INTKEY; */
+    u.by.flags = BTREE_INTKEY;
   }else{
-    u.bx.flags = BTREE_BLOBKEY;
+    u.by.flags = BTREE_BLOBKEY;
   }
-  rc = sqlite3BtreeCreateTable(u.bx.pDb->pBt, &u.bx.pgno, u.bx.flags);
-  pOut->u.i = u.bx.pgno;
+  rc = sqlite3BtreeCreateTable(u.by.pDb->pBt, &u.by.pgno, u.by.flags);
+  pOut->u.i = u.by.pgno;
   break;
 }
 
@@ -70654,44 +70409,44 @@ case OP_CreateTable: {          /* out2-prerelease */
 ** then runs the new virtual machine.  It is thus a re-entrant opcode.
 */
 case OP_ParseSchema: {
-#if 0  /* local variables moved into u.by */
+#if 0  /* local variables moved into u.bz */
   int iDb;
   const char *zMaster;
   char *zSql;
   InitData initData;
-#endif /* local variables moved into u.by */
+#endif /* local variables moved into u.bz */
 
   /* Any prepared statement that invokes this opcode will hold mutexes
   ** on every btree.  This is a prerequisite for invoking
   ** sqlite3InitCallback().
   */
 #ifdef SQLITE_DEBUG
-  for(u.by.iDb=0; u.by.iDb<db->nDb; u.by.iDb++){
-    assert( u.by.iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[u.by.iDb].pBt) );
+  for(u.bz.iDb=0; u.bz.iDb<db->nDb; u.bz.iDb++){
+    assert( u.bz.iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[u.bz.iDb].pBt) );
   }
 #endif
 
-  u.by.iDb = pOp->p1;
-  assert( u.by.iDb>=0 && u.by.iDb<db->nDb );
-  assert( DbHasProperty(db, u.by.iDb, DB_SchemaLoaded) );
+  u.bz.iDb = pOp->p1;
+  assert( u.bz.iDb>=0 && u.bz.iDb<db->nDb );
+  assert( DbHasProperty(db, u.bz.iDb, DB_SchemaLoaded) );
   /* Used to be a conditional */ {
-    u.by.zMaster = SCHEMA_TABLE(u.by.iDb);
-    u.by.initData.db = db;
-    u.by.initData.iDb = pOp->p1;
-    u.by.initData.pzErrMsg = &p->zErrMsg;
-    u.by.zSql = sqlite3MPrintf(db,
+    u.bz.zMaster = SCHEMA_TABLE(u.bz.iDb);
+    u.bz.initData.db = db;
+    u.bz.initData.iDb = pOp->p1;
+    u.bz.initData.pzErrMsg = &p->zErrMsg;
+    u.bz.zSql = sqlite3MPrintf(db,
        "SELECT name, rootpage, sql FROM '%q'.%s WHERE %s ORDER BY rowid",
-       db->aDb[u.by.iDb].zName, u.by.zMaster, pOp->p4.z);
-    if( u.by.zSql==0 ){
+       db->aDb[u.bz.iDb].zName, u.bz.zMaster, pOp->p4.z);
+    if( u.bz.zSql==0 ){
       rc = SQLITE_NOMEM;
     }else{
       assert( db->init.busy==0 );
       db->init.busy = 1;
-      u.by.initData.rc = SQLITE_OK;
+      u.bz.initData.rc = SQLITE_OK;
       assert( !db->mallocFailed );
-      rc = sqlite3_exec(db, u.by.zSql, sqlite3InitCallback, &u.by.initData, 0);
-      if( rc==SQLITE_OK ) rc = u.by.initData.rc;
-      sqlite3DbFree(db, u.by.zSql);
+      rc = sqlite3_exec(db, u.bz.zSql, sqlite3InitCallback, &u.bz.initData, 0);
+      if( rc==SQLITE_OK ) rc = u.bz.initData.rc;
+      sqlite3DbFree(db, u.bz.zSql);
       db->init.busy = 0;
     }
   }
@@ -70775,41 +70530,42 @@ case OP_DropTrigger: {
 ** This opcode is used to implement the integrity_check pragma.
 */
 case OP_IntegrityCk: {
-#if 0  /* local variables moved into u.bz */
+#if 0  /* local variables moved into u.ca */
   int nRoot;      /* Number of tables to check.  (Number of root pages.) */
   int *aRoot;     /* Array of rootpage numbers for tables to be checked */
   int j;          /* Loop counter */
   int nErr;       /* Number of errors reported */
   char *z;        /* Text of the error report */
   Mem *pnErr;     /* Register keeping track of errors remaining */
-#endif /* local variables moved into u.bz */
+#endif /* local variables moved into u.ca */
 
-  u.bz.nRoot = pOp->p2;
-  assert( u.bz.nRoot>0 );
-  u.bz.aRoot = sqlite3DbMallocRaw(db, sizeof(int)*(u.bz.nRoot+1) );
-  if( u.bz.aRoot==0 ) goto no_mem;
+  assert( p->bIsReader );
+  u.ca.nRoot = pOp->p2;
+  assert( u.ca.nRoot>0 );
+  u.ca.aRoot = sqlite3DbMallocRaw(db, sizeof(int)*(u.ca.nRoot+1) );
+  if( u.ca.aRoot==0 ) goto no_mem;
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  u.bz.pnErr = &aMem[pOp->p3];
-  assert( (u.bz.pnErr->flags & MEM_Int)!=0 );
-  assert( (u.bz.pnErr->flags & (MEM_Str|MEM_Blob))==0 );
+  u.ca.pnErr = &aMem[pOp->p3];
+  assert( (u.ca.pnErr->flags & MEM_Int)!=0 );
+  assert( (u.ca.pnErr->flags & (MEM_Str|MEM_Blob))==0 );
   pIn1 = &aMem[pOp->p1];
-  for(u.bz.j=0; u.bz.j<u.bz.nRoot; u.bz.j++){
-    u.bz.aRoot[u.bz.j] = (int)sqlite3VdbeIntValue(&pIn1[u.bz.j]);
+  for(u.ca.j=0; u.ca.j<u.ca.nRoot; u.ca.j++){
+    u.ca.aRoot[u.ca.j] = (int)sqlite3VdbeIntValue(&pIn1[u.ca.j]);
   }
-  u.bz.aRoot[u.bz.j] = 0;
+  u.ca.aRoot[u.ca.j] = 0;
   assert( pOp->p5<db->nDb );
   assert( (p->btreeMask & (((yDbMask)1)<<pOp->p5))!=0 );
-  u.bz.z = sqlite3BtreeIntegrityCheck(db->aDb[pOp->p5].pBt, u.bz.aRoot, u.bz.nRoot,
-                                 (int)u.bz.pnErr->u.i, &u.bz.nErr);
-  sqlite3DbFree(db, u.bz.aRoot);
-  u.bz.pnErr->u.i -= u.bz.nErr;
+  u.ca.z = sqlite3BtreeIntegrityCheck(db->aDb[pOp->p5].pBt, u.ca.aRoot, u.ca.nRoot,
+                                 (int)u.ca.pnErr->u.i, &u.ca.nErr);
+  sqlite3DbFree(db, u.ca.aRoot);
+  u.ca.pnErr->u.i -= u.ca.nErr;
   sqlite3VdbeMemSetNull(pIn1);
-  if( u.bz.nErr==0 ){
-    assert( u.bz.z==0 );
-  }else if( u.bz.z==0 ){
+  if( u.ca.nErr==0 ){
+    assert( u.ca.z==0 );
+  }else if( u.ca.z==0 ){
     goto no_mem;
   }else{
-    sqlite3VdbeMemSetStr(pIn1, u.bz.z, -1, SQLITE_UTF8, sqlite3_free);
+    sqlite3VdbeMemSetStr(pIn1, u.ca.z, -1, SQLITE_UTF8, sqlite3_free);
   }
   UPDATE_MAX_BLOBSIZE(pIn1);
   sqlite3VdbeChangeEncoding(pIn1, encoding);
@@ -70843,22 +70599,22 @@ case OP_RowSetAdd: {       /* in1, in2 */
 ** unchanged and jump to instruction P2.
 */
 case OP_RowSetRead: {       /* jump, in1, out3 */
-#if 0  /* local variables moved into u.ca */
+#if 0  /* local variables moved into u.cb */
   i64 val;
-#endif /* local variables moved into u.ca */
-  CHECK_FOR_INTERRUPT;
+#endif /* local variables moved into u.cb */
+
   pIn1 = &aMem[pOp->p1];
   if( (pIn1->flags & MEM_RowSet)==0
-   || sqlite3RowSetNext(pIn1->u.pRowSet, &u.ca.val)==0
+   || sqlite3RowSetNext(pIn1->u.pRowSet, &u.cb.val)==0
   ){
     /* The boolean index is empty */
     sqlite3VdbeMemSetNull(pIn1);
     pc = pOp->p2 - 1;
   }else{
     /* A value was pulled from the index */
-    sqlite3VdbeMemSetInt64(&aMem[pOp->p3], u.ca.val);
+    sqlite3VdbeMemSetInt64(&aMem[pOp->p3], u.cb.val);
   }
-  break;
+  goto check_for_interrupt;
 }
 
 /* Opcode: RowSetTest P1 P2 P3 P4
@@ -70885,14 +70641,14 @@ case OP_RowSetRead: {       /* jump, in1, out3 */
 ** inserted as part of some other set).
 */
 case OP_RowSetTest: {                     /* jump, in1, in3 */
-#if 0  /* local variables moved into u.cb */
+#if 0  /* local variables moved into u.cc */
   int iSet;
   int exists;
-#endif /* local variables moved into u.cb */
+#endif /* local variables moved into u.cc */
 
   pIn1 = &aMem[pOp->p1];
   pIn3 = &aMem[pOp->p3];
-  u.cb.iSet = pOp->p4.i;
+  u.cc.iSet = pOp->p4.i;
   assert( pIn3->flags&MEM_Int );
 
   /* If there is anything other than a rowset object in memory cell P1,
@@ -70904,17 +70660,17 @@ case OP_RowSetTest: {                     /* jump, in1, in3 */
   }
 
   assert( pOp->p4type==P4_INT32 );
-  assert( u.cb.iSet==-1 || u.cb.iSet>=0 );
-  if( u.cb.iSet ){
-    u.cb.exists = sqlite3RowSetTest(pIn1->u.pRowSet,
-                               (u8)(u.cb.iSet>=0 ? u.cb.iSet & 0xf : 0xff),
+  assert( u.cc.iSet==-1 || u.cc.iSet>=0 );
+  if( u.cc.iSet ){
+    u.cc.exists = sqlite3RowSetTest(pIn1->u.pRowSet,
+                               (u8)(u.cc.iSet>=0 ? u.cc.iSet & 0xf : 0xff),
                                pIn3->u.i);
-    if( u.cb.exists ){
+    if( u.cc.exists ){
       pc = pOp->p2 - 1;
       break;
     }
   }
-  if( u.cb.iSet>=0 ){
+  if( u.cc.iSet>=0 ){
     sqlite3RowSetInsert(pIn1->u.pRowSet, pIn3->u.i);
   }
   break;
@@ -70937,7 +70693,7 @@ case OP_RowSetTest: {                     /* jump, in1, in3 */
 ** P4 is a pointer to the VM containing the trigger program.
 */
 case OP_Program: {        /* jump */
-#if 0  /* local variables moved into u.cc */
+#if 0  /* local variables moved into u.cd */
   int nMem;               /* Number of memory registers for sub-program */
   int nByte;              /* Bytes of runtime space required for sub-program */
   Mem *pRt;               /* Register to allocate runtime space */
@@ -70946,11 +70702,11 @@ case OP_Program: {        /* jump */
   VdbeFrame *pFrame;      /* New vdbe frame to execute in */
   SubProgram *pProgram;   /* Sub-program to execute */
   void *t;                /* Token identifying trigger */
-#endif /* local variables moved into u.cc */
+#endif /* local variables moved into u.cd */
 
-  u.cc.pProgram = pOp->p4.pProgram;
-  u.cc.pRt = &aMem[pOp->p3];
-  assert( u.cc.pProgram->nOp>0 );
+  u.cd.pProgram = pOp->p4.pProgram;
+  u.cd.pRt = &aMem[pOp->p3];
+  assert( u.cd.pProgram->nOp>0 );
 
   /* If the p5 flag is clear, then recursive invocation of triggers is
   ** disabled for backwards compatibility (p5 is set if this sub-program
@@ -70964,9 +70720,9 @@ case OP_Program: {        /* jump */
   ** single trigger all have the same value for the SubProgram.token
   ** variable.  */
   if( pOp->p5 ){
-    u.cc.t = u.cc.pProgram->token;
-    for(u.cc.pFrame=p->pFrame; u.cc.pFrame && u.cc.pFrame->token!=u.cc.t; u.cc.pFrame=u.cc.pFrame->pParent);
-    if( u.cc.pFrame ) break;
+    u.cd.t = u.cd.pProgram->token;
+    for(u.cd.pFrame=p->pFrame; u.cd.pFrame && u.cd.pFrame->token!=u.cd.t; u.cd.pFrame=u.cd.pFrame->pParent);
+    if( u.cd.pFrame ) break;
   }
 
   if( p->nFrame>=db->aLimit[SQLITE_LIMIT_TRIGGER_DEPTH] ){
@@ -70975,69 +70731,69 @@ case OP_Program: {        /* jump */
     break;
   }
 
-  /* Register u.cc.pRt is used to store the memory required to save the state
+  /* Register u.cd.pRt is used to store the memory required to save the state
   ** of the current program, and the memory required at runtime to execute
-  ** the trigger program. If this trigger has been fired before, then u.cc.pRt
+  ** the trigger program. If this trigger has been fired before, then u.cd.pRt
   ** is already allocated. Otherwise, it must be initialized.  */
-  if( (u.cc.pRt->flags&MEM_Frame)==0 ){
+  if( (u.cd.pRt->flags&MEM_Frame)==0 ){
     /* SubProgram.nMem is set to the number of memory cells used by the
     ** program stored in SubProgram.aOp. As well as these, one memory
     ** cell is required for each cursor used by the program. Set local
-    ** variable u.cc.nMem (and later, VdbeFrame.nChildMem) to this value.
+    ** variable u.cd.nMem (and later, VdbeFrame.nChildMem) to this value.
     */
-    u.cc.nMem = u.cc.pProgram->nMem + u.cc.pProgram->nCsr;
-    u.cc.nByte = ROUND8(sizeof(VdbeFrame))
-              + u.cc.nMem * sizeof(Mem)
-              + u.cc.pProgram->nCsr * sizeof(VdbeCursor *)
-              + u.cc.pProgram->nOnce * sizeof(u8);
-    u.cc.pFrame = sqlite3DbMallocZero(db, u.cc.nByte);
-    if( !u.cc.pFrame ){
+    u.cd.nMem = u.cd.pProgram->nMem + u.cd.pProgram->nCsr;
+    u.cd.nByte = ROUND8(sizeof(VdbeFrame))
+              + u.cd.nMem * sizeof(Mem)
+              + u.cd.pProgram->nCsr * sizeof(VdbeCursor *)
+              + u.cd.pProgram->nOnce * sizeof(u8);
+    u.cd.pFrame = sqlite3DbMallocZero(db, u.cd.nByte);
+    if( !u.cd.pFrame ){
       goto no_mem;
     }
-    sqlite3VdbeMemRelease(u.cc.pRt);
-    u.cc.pRt->flags = MEM_Frame;
-    u.cc.pRt->u.pFrame = u.cc.pFrame;
+    sqlite3VdbeMemRelease(u.cd.pRt);
+    u.cd.pRt->flags = MEM_Frame;
+    u.cd.pRt->u.pFrame = u.cd.pFrame;
 
-    u.cc.pFrame->v = p;
-    u.cc.pFrame->nChildMem = u.cc.nMem;
-    u.cc.pFrame->nChildCsr = u.cc.pProgram->nCsr;
-    u.cc.pFrame->pc = pc;
-    u.cc.pFrame->aMem = p->aMem;
-    u.cc.pFrame->nMem = p->nMem;
-    u.cc.pFrame->apCsr = p->apCsr;
-    u.cc.pFrame->nCursor = p->nCursor;
-    u.cc.pFrame->aOp = p->aOp;
-    u.cc.pFrame->nOp = p->nOp;
-    u.cc.pFrame->token = u.cc.pProgram->token;
-    u.cc.pFrame->aOnceFlag = p->aOnceFlag;
-    u.cc.pFrame->nOnceFlag = p->nOnceFlag;
+    u.cd.pFrame->v = p;
+    u.cd.pFrame->nChildMem = u.cd.nMem;
+    u.cd.pFrame->nChildCsr = u.cd.pProgram->nCsr;
+    u.cd.pFrame->pc = pc;
+    u.cd.pFrame->aMem = p->aMem;
+    u.cd.pFrame->nMem = p->nMem;
+    u.cd.pFrame->apCsr = p->apCsr;
+    u.cd.pFrame->nCursor = p->nCursor;
+    u.cd.pFrame->aOp = p->aOp;
+    u.cd.pFrame->nOp = p->nOp;
+    u.cd.pFrame->token = u.cd.pProgram->token;
+    u.cd.pFrame->aOnceFlag = p->aOnceFlag;
+    u.cd.pFrame->nOnceFlag = p->nOnceFlag;
 
-    u.cc.pEnd = &VdbeFrameMem(u.cc.pFrame)[u.cc.pFrame->nChildMem];
-    for(u.cc.pMem=VdbeFrameMem(u.cc.pFrame); u.cc.pMem!=u.cc.pEnd; u.cc.pMem++){
-      u.cc.pMem->flags = MEM_Invalid;
-      u.cc.pMem->db = db;
+    u.cd.pEnd = &VdbeFrameMem(u.cd.pFrame)[u.cd.pFrame->nChildMem];
+    for(u.cd.pMem=VdbeFrameMem(u.cd.pFrame); u.cd.pMem!=u.cd.pEnd; u.cd.pMem++){
+      u.cd.pMem->flags = MEM_Invalid;
+      u.cd.pMem->db = db;
     }
   }else{
-    u.cc.pFrame = u.cc.pRt->u.pFrame;
-    assert( u.cc.pProgram->nMem+u.cc.pProgram->nCsr==u.cc.pFrame->nChildMem );
-    assert( u.cc.pProgram->nCsr==u.cc.pFrame->nChildCsr );
-    assert( pc==u.cc.pFrame->pc );
+    u.cd.pFrame = u.cd.pRt->u.pFrame;
+    assert( u.cd.pProgram->nMem+u.cd.pProgram->nCsr==u.cd.pFrame->nChildMem );
+    assert( u.cd.pProgram->nCsr==u.cd.pFrame->nChildCsr );
+    assert( pc==u.cd.pFrame->pc );
   }
 
   p->nFrame++;
-  u.cc.pFrame->pParent = p->pFrame;
-  u.cc.pFrame->lastRowid = lastRowid;
-  u.cc.pFrame->nChange = p->nChange;
+  u.cd.pFrame->pParent = p->pFrame;
+  u.cd.pFrame->lastRowid = lastRowid;
+  u.cd.pFrame->nChange = p->nChange;
   p->nChange = 0;
-  p->pFrame = u.cc.pFrame;
-  p->aMem = aMem = &VdbeFrameMem(u.cc.pFrame)[-1];
-  p->nMem = u.cc.pFrame->nChildMem;
-  p->nCursor = (u16)u.cc.pFrame->nChildCsr;
+  p->pFrame = u.cd.pFrame;
+  p->aMem = aMem = &VdbeFrameMem(u.cd.pFrame)[-1];
+  p->nMem = u.cd.pFrame->nChildMem;
+  p->nCursor = (u16)u.cd.pFrame->nChildCsr;
   p->apCsr = (VdbeCursor **)&aMem[p->nMem+1];
-  p->aOp = aOp = u.cc.pProgram->aOp;
-  p->nOp = u.cc.pProgram->nOp;
+  p->aOp = aOp = u.cd.pProgram->aOp;
+  p->nOp = u.cd.pProgram->nOp;
   p->aOnceFlag = (u8 *)&p->apCsr[p->nCursor];
-  p->nOnceFlag = u.cc.pProgram->nOnce;
+  p->nOnceFlag = u.cd.pProgram->nOnce;
   pc = -1;
   memset(p->aOnceFlag, 0, p->nOnceFlag);
 
@@ -71057,13 +70813,13 @@ case OP_Program: {        /* jump */
 ** calling OP_Program instruction.
 */
 case OP_Param: {           /* out2-prerelease */
-#if 0  /* local variables moved into u.cd */
+#if 0  /* local variables moved into u.ce */
   VdbeFrame *pFrame;
   Mem *pIn;
-#endif /* local variables moved into u.cd */
-  u.cd.pFrame = p->pFrame;
-  u.cd.pIn = &u.cd.pFrame->aMem[pOp->p1 + u.cd.pFrame->aOp[u.cd.pFrame->pc].p1];
-  sqlite3VdbeMemShallowCopy(pOut, u.cd.pIn, MEM_Ephem);
+#endif /* local variables moved into u.ce */
+  u.ce.pFrame = p->pFrame;
+  u.ce.pIn = &u.ce.pFrame->aMem[pOp->p1 + u.ce.pFrame->aOp[u.ce.pFrame->pc].p1];
+  sqlite3VdbeMemShallowCopy(pOut, u.ce.pIn, MEM_Ephem);
   break;
 }
 
@@ -71078,7 +70834,9 @@ case OP_Param: {           /* out2-prerelease */
 ** statement counter is incremented (immediate foreign key constraints).
 */
 case OP_FkCounter: {
-  if( pOp->p1 ){
+  if( db->flags & SQLITE_DeferFKs ){
+    db->nDeferredImmCons += pOp->p2;
+  }else if( pOp->p1 ){
     db->nDeferredCons += pOp->p2;
   }else{
     p->nFkConstraint += pOp->p2;
@@ -71099,9 +70857,9 @@ case OP_FkCounter: {
 */
 case OP_FkIfZero: {         /* jump */
   if( pOp->p1 ){
-    if( db->nDeferredCons==0 ) pc = pOp->p2-1;
+    if( db->nDeferredCons==0 && db->nDeferredImmCons==0 ) pc = pOp->p2-1;
   }else{
-    if( p->nFkConstraint==0 ) pc = pOp->p2-1;
+    if( p->nFkConstraint==0 && db->nDeferredImmCons==0 ) pc = pOp->p2-1;
   }
   break;
 }
@@ -71119,22 +70877,22 @@ case OP_FkIfZero: {         /* jump */
 ** an integer.
 */
 case OP_MemMax: {        /* in2 */
-#if 0  /* local variables moved into u.ce */
+#if 0  /* local variables moved into u.cf */
   Mem *pIn1;
   VdbeFrame *pFrame;
-#endif /* local variables moved into u.ce */
+#endif /* local variables moved into u.cf */
   if( p->pFrame ){
-    for(u.ce.pFrame=p->pFrame; u.ce.pFrame->pParent; u.ce.pFrame=u.ce.pFrame->pParent);
-    u.ce.pIn1 = &u.ce.pFrame->aMem[pOp->p1];
+    for(u.cf.pFrame=p->pFrame; u.cf.pFrame->pParent; u.cf.pFrame=u.cf.pFrame->pParent);
+    u.cf.pIn1 = &u.cf.pFrame->aMem[pOp->p1];
   }else{
-    u.ce.pIn1 = &aMem[pOp->p1];
+    u.cf.pIn1 = &aMem[pOp->p1];
   }
-  assert( memIsValid(u.ce.pIn1) );
-  sqlite3VdbeMemIntegerify(u.ce.pIn1);
+  assert( memIsValid(u.cf.pIn1) );
+  sqlite3VdbeMemIntegerify(u.cf.pIn1);
   pIn2 = &aMem[pOp->p2];
   sqlite3VdbeMemIntegerify(pIn2);
-  if( u.ce.pIn1->u.i<pIn2->u.i){
-    u.ce.pIn1->u.i = pIn2->u.i;
+  if( u.cf.pIn1->u.i<pIn2->u.i){
+    u.cf.pIn1->u.i = pIn2->u.i;
   }
   break;
 }
@@ -71201,56 +70959,56 @@ case OP_IfZero: {        /* jump, in1 */
 ** successors.
 */
 case OP_AggStep: {
-#if 0  /* local variables moved into u.cf */
+#if 0  /* local variables moved into u.cg */
   int n;
   int i;
   Mem *pMem;
   Mem *pRec;
   sqlite3_context ctx;
   sqlite3_value **apVal;
-#endif /* local variables moved into u.cf */
+#endif /* local variables moved into u.cg */
 
-  u.cf.n = pOp->p5;
-  assert( u.cf.n>=0 );
-  u.cf.pRec = &aMem[pOp->p2];
-  u.cf.apVal = p->apArg;
-  assert( u.cf.apVal || u.cf.n==0 );
-  for(u.cf.i=0; u.cf.i<u.cf.n; u.cf.i++, u.cf.pRec++){
-    assert( memIsValid(u.cf.pRec) );
-    u.cf.apVal[u.cf.i] = u.cf.pRec;
-    memAboutToChange(p, u.cf.pRec);
-    sqlite3VdbeMemStoreType(u.cf.pRec);
+  u.cg.n = pOp->p5;
+  assert( u.cg.n>=0 );
+  u.cg.pRec = &aMem[pOp->p2];
+  u.cg.apVal = p->apArg;
+  assert( u.cg.apVal || u.cg.n==0 );
+  for(u.cg.i=0; u.cg.i<u.cg.n; u.cg.i++, u.cg.pRec++){
+    assert( memIsValid(u.cg.pRec) );
+    u.cg.apVal[u.cg.i] = u.cg.pRec;
+    memAboutToChange(p, u.cg.pRec);
+    sqlite3VdbeMemStoreType(u.cg.pRec);
   }
-  u.cf.ctx.pFunc = pOp->p4.pFunc;
+  u.cg.ctx.pFunc = pOp->p4.pFunc;
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  u.cf.ctx.pMem = u.cf.pMem = &aMem[pOp->p3];
-  u.cf.pMem->n++;
-  u.cf.ctx.s.flags = MEM_Null;
-  u.cf.ctx.s.z = 0;
-  u.cf.ctx.s.zMalloc = 0;
-  u.cf.ctx.s.xDel = 0;
-  u.cf.ctx.s.db = db;
-  u.cf.ctx.isError = 0;
-  u.cf.ctx.pColl = 0;
-  u.cf.ctx.skipFlag = 0;
-  if( u.cf.ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
+  u.cg.ctx.pMem = u.cg.pMem = &aMem[pOp->p3];
+  u.cg.pMem->n++;
+  u.cg.ctx.s.flags = MEM_Null;
+  u.cg.ctx.s.z = 0;
+  u.cg.ctx.s.zMalloc = 0;
+  u.cg.ctx.s.xDel = 0;
+  u.cg.ctx.s.db = db;
+  u.cg.ctx.isError = 0;
+  u.cg.ctx.pColl = 0;
+  u.cg.ctx.skipFlag = 0;
+  if( u.cg.ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
     assert( pOp>p->aOp );
     assert( pOp[-1].p4type==P4_COLLSEQ );
     assert( pOp[-1].opcode==OP_CollSeq );
-    u.cf.ctx.pColl = pOp[-1].p4.pColl;
+    u.cg.ctx.pColl = pOp[-1].p4.pColl;
   }
-  (u.cf.ctx.pFunc->xStep)(&u.cf.ctx, u.cf.n, u.cf.apVal); /* IMP: R-24505-23230 */
-  if( u.cf.ctx.isError ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&u.cf.ctx.s));
-    rc = u.cf.ctx.isError;
+  (u.cg.ctx.pFunc->xStep)(&u.cg.ctx, u.cg.n, u.cg.apVal); /* IMP: R-24505-23230 */
+  if( u.cg.ctx.isError ){
+    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(&u.cg.ctx.s));
+    rc = u.cg.ctx.isError;
   }
-  if( u.cf.ctx.skipFlag ){
+  if( u.cg.ctx.skipFlag ){
     assert( pOp[-1].opcode==OP_CollSeq );
-    u.cf.i = pOp[-1].p1;
-    if( u.cf.i ) sqlite3VdbeMemSetInt64(&aMem[u.cf.i], 1);
+    u.cg.i = pOp[-1].p1;
+    if( u.cg.i ) sqlite3VdbeMemSetInt64(&aMem[u.cg.i], 1);
   }
 
-  sqlite3VdbeMemRelease(&u.cf.ctx.s);
+  sqlite3VdbeMemRelease(&u.cg.ctx.s);
 
   break;
 }
@@ -71268,19 +71026,19 @@ case OP_AggStep: {
 ** the step function was not previously called.
 */
 case OP_AggFinal: {
-#if 0  /* local variables moved into u.cg */
+#if 0  /* local variables moved into u.ch */
   Mem *pMem;
-#endif /* local variables moved into u.cg */
+#endif /* local variables moved into u.ch */
   assert( pOp->p1>0 && pOp->p1<=p->nMem );
-  u.cg.pMem = &aMem[pOp->p1];
-  assert( (u.cg.pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
-  rc = sqlite3VdbeMemFinalize(u.cg.pMem, pOp->p4.pFunc);
+  u.ch.pMem = &aMem[pOp->p1];
+  assert( (u.ch.pMem->flags & ~(MEM_Null|MEM_Agg))==0 );
+  rc = sqlite3VdbeMemFinalize(u.ch.pMem, pOp->p4.pFunc);
   if( rc ){
-    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(u.cg.pMem));
+    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3_value_text(u.ch.pMem));
   }
-  sqlite3VdbeChangeEncoding(u.cg.pMem, encoding);
-  UPDATE_MAX_BLOBSIZE(u.cg.pMem);
-  if( sqlite3VdbeMemTooBig(u.cg.pMem) ){
+  sqlite3VdbeChangeEncoding(u.ch.pMem, encoding);
+  UPDATE_MAX_BLOBSIZE(u.ch.pMem);
+  if( sqlite3VdbeMemTooBig(u.ch.pMem) ){
     goto too_big;
   }
   break;
@@ -71299,25 +71057,26 @@ case OP_AggFinal: {
 ** mem[P3+2] are initialized to -1.
 */
 case OP_Checkpoint: {
-#if 0  /* local variables moved into u.ch */
+#if 0  /* local variables moved into u.ci */
   int i;                          /* Loop counter */
   int aRes[3];                    /* Results */
   Mem *pMem;                      /* Write results here */
-#endif /* local variables moved into u.ch */
+#endif /* local variables moved into u.ci */
 
-  u.ch.aRes[0] = 0;
-  u.ch.aRes[1] = u.ch.aRes[2] = -1;
+  assert( p->readOnly==0 );
+  u.ci.aRes[0] = 0;
+  u.ci.aRes[1] = u.ci.aRes[2] = -1;
   assert( pOp->p2==SQLITE_CHECKPOINT_PASSIVE
        || pOp->p2==SQLITE_CHECKPOINT_FULL
        || pOp->p2==SQLITE_CHECKPOINT_RESTART
   );
-  rc = sqlite3Checkpoint(db, pOp->p1, pOp->p2, &u.ch.aRes[1], &u.ch.aRes[2]);
+  rc = sqlite3Checkpoint(db, pOp->p1, pOp->p2, &u.ci.aRes[1], &u.ci.aRes[2]);
   if( rc==SQLITE_BUSY ){
     rc = SQLITE_OK;
-    u.ch.aRes[0] = 1;
+    u.ci.aRes[0] = 1;
   }
-  for(u.ch.i=0, u.ch.pMem = &aMem[pOp->p3]; u.ch.i<3; u.ch.i++, u.ch.pMem++){
-    sqlite3VdbeMemSetInt64(u.ch.pMem, (i64)u.ch.aRes[u.ch.i]);
+  for(u.ci.i=0, u.ci.pMem = &aMem[pOp->p3]; u.ci.i<3; u.ci.i++, u.ci.pMem++){
+    sqlite3VdbeMemSetInt64(u.ci.pMem, (i64)u.ci.aRes[u.ci.i]);
   }
   break;
 };  
@@ -71336,91 +71095,94 @@ case OP_Checkpoint: {
 ** Write a string containing the final journal-mode to register P2.
 */
 case OP_JournalMode: {    /* out2-prerelease */
-#if 0  /* local variables moved into u.ci */
+#if 0  /* local variables moved into u.cj */
   Btree *pBt;                     /* Btree to change journal mode of */
   Pager *pPager;                  /* Pager associated with pBt */
   int eNew;                       /* New journal mode */
   int eOld;                       /* The old journal mode */
+#ifndef SQLITE_OMIT_WAL
   const char *zFilename;          /* Name of database file for pPager */
-#endif /* local variables moved into u.ci */
+#endif
+#endif /* local variables moved into u.cj */
 
-  u.ci.eNew = pOp->p3;
-  assert( u.ci.eNew==PAGER_JOURNALMODE_DELETE
-       || u.ci.eNew==PAGER_JOURNALMODE_TRUNCATE
-       || u.ci.eNew==PAGER_JOURNALMODE_PERSIST
-       || u.ci.eNew==PAGER_JOURNALMODE_OFF
-       || u.ci.eNew==PAGER_JOURNALMODE_MEMORY
-       || u.ci.eNew==PAGER_JOURNALMODE_WAL
-       || u.ci.eNew==PAGER_JOURNALMODE_QUERY
+  u.cj.eNew = pOp->p3;
+  assert( u.cj.eNew==PAGER_JOURNALMODE_DELETE
+       || u.cj.eNew==PAGER_JOURNALMODE_TRUNCATE
+       || u.cj.eNew==PAGER_JOURNALMODE_PERSIST
+       || u.cj.eNew==PAGER_JOURNALMODE_OFF
+       || u.cj.eNew==PAGER_JOURNALMODE_MEMORY
+       || u.cj.eNew==PAGER_JOURNALMODE_WAL
+       || u.cj.eNew==PAGER_JOURNALMODE_QUERY
   );
   assert( pOp->p1>=0 && pOp->p1<db->nDb );
+  assert( p->readOnly==0 );
 
-  u.ci.pBt = db->aDb[pOp->p1].pBt;
-  u.ci.pPager = sqlite3BtreePager(u.ci.pBt);
-  u.ci.eOld = sqlite3PagerGetJournalMode(u.ci.pPager);
-  if( u.ci.eNew==PAGER_JOURNALMODE_QUERY ) u.ci.eNew = u.ci.eOld;
-  if( !sqlite3PagerOkToChangeJournalMode(u.ci.pPager) ) u.ci.eNew = u.ci.eOld;
+  u.cj.pBt = db->aDb[pOp->p1].pBt;
+  u.cj.pPager = sqlite3BtreePager(u.cj.pBt);
+  u.cj.eOld = sqlite3PagerGetJournalMode(u.cj.pPager);
+  if( u.cj.eNew==PAGER_JOURNALMODE_QUERY ) u.cj.eNew = u.cj.eOld;
+  if( !sqlite3PagerOkToChangeJournalMode(u.cj.pPager) ) u.cj.eNew = u.cj.eOld;
 
 #ifndef SQLITE_OMIT_WAL
-  u.ci.zFilename = sqlite3PagerFilename(u.ci.pPager, 1);
+  u.cj.zFilename = sqlite3PagerFilename(u.cj.pPager, 1);
 
   /* Do not allow a transition to journal_mode=WAL for a database
   ** in temporary storage or if the VFS does not support shared memory
   */
-  if( u.ci.eNew==PAGER_JOURNALMODE_WAL
-   && (sqlite3Strlen30(u.ci.zFilename)==0           /* Temp file */
-       || !sqlite3PagerWalSupported(u.ci.pPager))   /* No shared-memory support */
+  if( u.cj.eNew==PAGER_JOURNALMODE_WAL
+   && (sqlite3Strlen30(u.cj.zFilename)==0           /* Temp file */
+       || !sqlite3PagerWalSupported(u.cj.pPager))   /* No shared-memory support */
   ){
-    u.ci.eNew = u.ci.eOld;
+    u.cj.eNew = u.cj.eOld;
   }
 
-  if( (u.ci.eNew!=u.ci.eOld)
-   && (u.ci.eOld==PAGER_JOURNALMODE_WAL || u.ci.eNew==PAGER_JOURNALMODE_WAL)
+  if( (u.cj.eNew!=u.cj.eOld)
+   && (u.cj.eOld==PAGER_JOURNALMODE_WAL || u.cj.eNew==PAGER_JOURNALMODE_WAL)
   ){
-    if( !db->autoCommit || db->activeVdbeCnt>1 ){
+    if( !db->autoCommit || db->nVdbeRead>1 ){
       rc = SQLITE_ERROR;
       sqlite3SetString(&p->zErrMsg, db,
           "cannot change %s wal mode from within a transaction",
-          (u.ci.eNew==PAGER_JOURNALMODE_WAL ? "into" : "out of")
+          (u.cj.eNew==PAGER_JOURNALMODE_WAL ? "into" : "out of")
       );
       break;
     }else{
 
-      if( u.ci.eOld==PAGER_JOURNALMODE_WAL ){
+      if( u.cj.eOld==PAGER_JOURNALMODE_WAL ){
         /* If leaving WAL mode, close the log file. If successful, the call
         ** to PagerCloseWal() checkpoints and deletes the write-ahead-log
         ** file. An EXCLUSIVE lock may still be held on the database file
         ** after a successful return.
         */
-        rc = sqlite3PagerCloseWal(u.ci.pPager);
+        rc = sqlite3PagerCloseWal(u.cj.pPager);
         if( rc==SQLITE_OK ){
-          sqlite3PagerSetJournalMode(u.ci.pPager, u.ci.eNew);
+          sqlite3PagerSetJournalMode(u.cj.pPager, u.cj.eNew);
         }
-      }else if( u.ci.eOld==PAGER_JOURNALMODE_MEMORY ){
+      }else if( u.cj.eOld==PAGER_JOURNALMODE_MEMORY ){
         /* Cannot transition directly from MEMORY to WAL.  Use mode OFF
         ** as an intermediate */
-        sqlite3PagerSetJournalMode(u.ci.pPager, PAGER_JOURNALMODE_OFF);
+        sqlite3PagerSetJournalMode(u.cj.pPager, PAGER_JOURNALMODE_OFF);
       }
 
       /* Open a transaction on the database file. Regardless of the journal
       ** mode, this transaction always uses a rollback journal.
       */
-      assert( sqlite3BtreeIsInTrans(u.ci.pBt)==0 );
+      assert( sqlite3BtreeIsInTrans(u.cj.pBt)==0 );
       if( rc==SQLITE_OK ){
-        rc = sqlite3BtreeSetVersion(u.ci.pBt, (u.ci.eNew==PAGER_JOURNALMODE_WAL ? 2 : 1));
+        rc = sqlite3BtreeSetVersion(u.cj.pBt, (u.cj.eNew==PAGER_JOURNALMODE_WAL ? 2 : 1));
       }
     }
   }
 #endif /* ifndef SQLITE_OMIT_WAL */
 
   if( rc ){
-    u.ci.eNew = u.ci.eOld;
+    u.cj.eNew = u.cj.eOld;
   }
-  u.ci.eNew = sqlite3PagerSetJournalMode(u.ci.pPager, u.ci.eNew);
+  u.cj.eNew = sqlite3PagerSetJournalMode(u.cj.pPager, u.cj.eNew);
 
   pOut = &aMem[pOp->p2];
   pOut->flags = MEM_Str|MEM_Static|MEM_Term;
-  pOut->z = (char *)sqlite3JournalModename(u.ci.eNew);
+  pOut->z = (char *)sqlite3JournalModename(u.cj.eNew);
   pOut->n = sqlite3Strlen30(pOut->z);
   pOut->enc = SQLITE_UTF8;
   sqlite3VdbeChangeEncoding(pOut, encoding);
@@ -71436,6 +71198,7 @@ case OP_JournalMode: {    /* out2-prerelease */
 ** a transaction.
 */
 case OP_Vacuum: {
+  assert( p->readOnly==0 );
   rc = sqlite3RunVacuum(&p->zErrMsg, db);
   break;
 }
@@ -71449,14 +71212,15 @@ case OP_Vacuum: {
 ** P2. Otherwise, fall through to the next instruction.
 */
 case OP_IncrVacuum: {        /* jump */
-#if 0  /* local variables moved into u.cj */
+#if 0  /* local variables moved into u.ck */
   Btree *pBt;
-#endif /* local variables moved into u.cj */
+#endif /* local variables moved into u.ck */
 
   assert( pOp->p1>=0 && pOp->p1<db->nDb );
   assert( (p->btreeMask & (((yDbMask)1)<<pOp->p1))!=0 );
-  u.cj.pBt = db->aDb[pOp->p1].pBt;
-  rc = sqlite3BtreeIncrVacuum(u.cj.pBt);
+  assert( p->readOnly==0 );
+  u.ck.pBt = db->aDb[pOp->p1].pBt;
+  rc = sqlite3BtreeIncrVacuum(u.ck.pBt);
   if( rc==SQLITE_DONE ){
     pc = pOp->p2 - 1;
     rc = SQLITE_OK;
@@ -71526,12 +71290,12 @@ case OP_TableLock: {
 ** code will be set to SQLITE_LOCKED.
 */
 case OP_VBegin: {
-#if 0  /* local variables moved into u.ck */
+#if 0  /* local variables moved into u.cl */
   VTable *pVTab;
-#endif /* local variables moved into u.ck */
-  u.ck.pVTab = pOp->p4.pVtab;
-  rc = sqlite3VtabBegin(db, u.ck.pVTab);
-  if( u.ck.pVTab ) importVtabErrMsg(p, u.ck.pVTab->pVtab);
+#endif /* local variables moved into u.cl */
+  u.cl.pVTab = pOp->p4.pVtab;
+  rc = sqlite3VtabBegin(db, u.cl.pVTab);
+  if( u.cl.pVTab ) sqlite3VtabImportErrmsg(p, u.cl.pVTab->pVtab);
   break;
 }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
@@ -71570,32 +71334,33 @@ case OP_VDestroy: {
 ** table and stores that cursor in P1.
 */
 case OP_VOpen: {
-#if 0  /* local variables moved into u.cl */
+#if 0  /* local variables moved into u.cm */
   VdbeCursor *pCur;
   sqlite3_vtab_cursor *pVtabCursor;
   sqlite3_vtab *pVtab;
   sqlite3_module *pModule;
-#endif /* local variables moved into u.cl */
+#endif /* local variables moved into u.cm */
 
-  u.cl.pCur = 0;
-  u.cl.pVtabCursor = 0;
-  u.cl.pVtab = pOp->p4.pVtab->pVtab;
-  u.cl.pModule = (sqlite3_module *)u.cl.pVtab->pModule;
-  assert(u.cl.pVtab && u.cl.pModule);
-  rc = u.cl.pModule->xOpen(u.cl.pVtab, &u.cl.pVtabCursor);
-  importVtabErrMsg(p, u.cl.pVtab);
+  assert( p->bIsReader );
+  u.cm.pCur = 0;
+  u.cm.pVtabCursor = 0;
+  u.cm.pVtab = pOp->p4.pVtab->pVtab;
+  u.cm.pModule = (sqlite3_module *)u.cm.pVtab->pModule;
+  assert(u.cm.pVtab && u.cm.pModule);
+  rc = u.cm.pModule->xOpen(u.cm.pVtab, &u.cm.pVtabCursor);
+  sqlite3VtabImportErrmsg(p, u.cm.pVtab);
   if( SQLITE_OK==rc ){
     /* Initialize sqlite3_vtab_cursor base class */
-    u.cl.pVtabCursor->pVtab = u.cl.pVtab;
+    u.cm.pVtabCursor->pVtab = u.cm.pVtab;
 
-    /* Initialise vdbe cursor object */
-    u.cl.pCur = allocateCursor(p, pOp->p1, 0, -1, 0);
-    if( u.cl.pCur ){
-      u.cl.pCur->pVtabCursor = u.cl.pVtabCursor;
-      u.cl.pCur->pModule = u.cl.pVtabCursor->pVtab->pModule;
+    /* Initialize vdbe cursor object */
+    u.cm.pCur = allocateCursor(p, pOp->p1, 0, -1, 0);
+    if( u.cm.pCur ){
+      u.cm.pCur->pVtabCursor = u.cm.pVtabCursor;
+      u.cm.pCur->pModule = u.cm.pVtabCursor->pVtab->pModule;
     }else{
       db->mallocFailed = 1;
-      u.cl.pModule->xClose(u.cl.pVtabCursor);
+      u.cm.pModule->xClose(u.cm.pVtabCursor);
     }
   }
   break;
@@ -71622,7 +71387,7 @@ case OP_VOpen: {
 ** A jump is made to P2 if the result set after filtering would be empty.
 */
 case OP_VFilter: {   /* jump */
-#if 0  /* local variables moved into u.cm */
+#if 0  /* local variables moved into u.cn */
   int nArg;
   int iQuery;
   const sqlite3_module *pModule;
@@ -71634,45 +71399,45 @@ case OP_VFilter: {   /* jump */
   int res;
   int i;
   Mem **apArg;
-#endif /* local variables moved into u.cm */
+#endif /* local variables moved into u.cn */
 
-  u.cm.pQuery = &aMem[pOp->p3];
-  u.cm.pArgc = &u.cm.pQuery[1];
-  u.cm.pCur = p->apCsr[pOp->p1];
-  assert( memIsValid(u.cm.pQuery) );
-  REGISTER_TRACE(pOp->p3, u.cm.pQuery);
-  assert( u.cm.pCur->pVtabCursor );
-  u.cm.pVtabCursor = u.cm.pCur->pVtabCursor;
-  u.cm.pVtab = u.cm.pVtabCursor->pVtab;
-  u.cm.pModule = u.cm.pVtab->pModule;
+  u.cn.pQuery = &aMem[pOp->p3];
+  u.cn.pArgc = &u.cn.pQuery[1];
+  u.cn.pCur = p->apCsr[pOp->p1];
+  assert( memIsValid(u.cn.pQuery) );
+  REGISTER_TRACE(pOp->p3, u.cn.pQuery);
+  assert( u.cn.pCur->pVtabCursor );
+  u.cn.pVtabCursor = u.cn.pCur->pVtabCursor;
+  u.cn.pVtab = u.cn.pVtabCursor->pVtab;
+  u.cn.pModule = u.cn.pVtab->pModule;
 
   /* Grab the index number and argc parameters */
-  assert( (u.cm.pQuery->flags&MEM_Int)!=0 && u.cm.pArgc->flags==MEM_Int );
-  u.cm.nArg = (int)u.cm.pArgc->u.i;
-  u.cm.iQuery = (int)u.cm.pQuery->u.i;
+  assert( (u.cn.pQuery->flags&MEM_Int)!=0 && u.cn.pArgc->flags==MEM_Int );
+  u.cn.nArg = (int)u.cn.pArgc->u.i;
+  u.cn.iQuery = (int)u.cn.pQuery->u.i;
 
   /* Invoke the xFilter method */
   {
-    u.cm.res = 0;
-    u.cm.apArg = p->apArg;
-    for(u.cm.i = 0; u.cm.i<u.cm.nArg; u.cm.i++){
-      u.cm.apArg[u.cm.i] = &u.cm.pArgc[u.cm.i+1];
-      sqlite3VdbeMemStoreType(u.cm.apArg[u.cm.i]);
+    u.cn.res = 0;
+    u.cn.apArg = p->apArg;
+    for(u.cn.i = 0; u.cn.i<u.cn.nArg; u.cn.i++){
+      u.cn.apArg[u.cn.i] = &u.cn.pArgc[u.cn.i+1];
+      sqlite3VdbeMemStoreType(u.cn.apArg[u.cn.i]);
     }
 
     p->inVtabMethod = 1;
-    rc = u.cm.pModule->xFilter(u.cm.pVtabCursor, u.cm.iQuery, pOp->p4.z, u.cm.nArg, u.cm.apArg);
+    rc = u.cn.pModule->xFilter(u.cn.pVtabCursor, u.cn.iQuery, pOp->p4.z, u.cn.nArg, u.cn.apArg);
     p->inVtabMethod = 0;
-    importVtabErrMsg(p, u.cm.pVtab);
+    sqlite3VtabImportErrmsg(p, u.cn.pVtab);
     if( rc==SQLITE_OK ){
-      u.cm.res = u.cm.pModule->xEof(u.cm.pVtabCursor);
+      u.cn.res = u.cn.pModule->xEof(u.cn.pVtabCursor);
     }
 
-    if( u.cm.res ){
+    if( u.cn.res ){
       pc = pOp->p2 - 1;
     }
   }
-  u.cm.pCur->nullRow = 0;
+  u.cn.pCur->nullRow = 0;
 
   break;
 }
@@ -71686,51 +71451,51 @@ case OP_VFilter: {   /* jump */
 ** P1 cursor is pointing to into register P3.
 */
 case OP_VColumn: {
-#if 0  /* local variables moved into u.cn */
+#if 0  /* local variables moved into u.co */
   sqlite3_vtab *pVtab;
   const sqlite3_module *pModule;
   Mem *pDest;
   sqlite3_context sContext;
-#endif /* local variables moved into u.cn */
+#endif /* local variables moved into u.co */
 
   VdbeCursor *pCur = p->apCsr[pOp->p1];
   assert( pCur->pVtabCursor );
   assert( pOp->p3>0 && pOp->p3<=p->nMem );
-  u.cn.pDest = &aMem[pOp->p3];
-  memAboutToChange(p, u.cn.pDest);
+  u.co.pDest = &aMem[pOp->p3];
+  memAboutToChange(p, u.co.pDest);
   if( pCur->nullRow ){
-    sqlite3VdbeMemSetNull(u.cn.pDest);
+    sqlite3VdbeMemSetNull(u.co.pDest);
     break;
   }
-  u.cn.pVtab = pCur->pVtabCursor->pVtab;
-  u.cn.pModule = u.cn.pVtab->pModule;
-  assert( u.cn.pModule->xColumn );
-  memset(&u.cn.sContext, 0, sizeof(u.cn.sContext));
+  u.co.pVtab = pCur->pVtabCursor->pVtab;
+  u.co.pModule = u.co.pVtab->pModule;
+  assert( u.co.pModule->xColumn );
+  memset(&u.co.sContext, 0, sizeof(u.co.sContext));
 
   /* The output cell may already have a buffer allocated. Move
-  ** the current contents to u.cn.sContext.s so in case the user-function
+  ** the current contents to u.co.sContext.s so in case the user-function
   ** can use the already allocated buffer instead of allocating a
   ** new one.
   */
-  sqlite3VdbeMemMove(&u.cn.sContext.s, u.cn.pDest);
-  MemSetTypeFlag(&u.cn.sContext.s, MEM_Null);
+  sqlite3VdbeMemMove(&u.co.sContext.s, u.co.pDest);
+  MemSetTypeFlag(&u.co.sContext.s, MEM_Null);
 
-  rc = u.cn.pModule->xColumn(pCur->pVtabCursor, &u.cn.sContext, pOp->p2);
-  importVtabErrMsg(p, u.cn.pVtab);
-  if( u.cn.sContext.isError ){
-    rc = u.cn.sContext.isError;
+  rc = u.co.pModule->xColumn(pCur->pVtabCursor, &u.co.sContext, pOp->p2);
+  sqlite3VtabImportErrmsg(p, u.co.pVtab);
+  if( u.co.sContext.isError ){
+    rc = u.co.sContext.isError;
   }
 
   /* Copy the result of the function to the P3 register. We
   ** do this regardless of whether or not an error occurred to ensure any
-  ** dynamic allocation in u.cn.sContext.s (a Mem struct) is  released.
+  ** dynamic allocation in u.co.sContext.s (a Mem struct) is  released.
   */
-  sqlite3VdbeChangeEncoding(&u.cn.sContext.s, encoding);
-  sqlite3VdbeMemMove(u.cn.pDest, &u.cn.sContext.s);
-  REGISTER_TRACE(pOp->p3, u.cn.pDest);
-  UPDATE_MAX_BLOBSIZE(u.cn.pDest);
+  sqlite3VdbeChangeEncoding(&u.co.sContext.s, encoding);
+  sqlite3VdbeMemMove(u.co.pDest, &u.co.sContext.s);
+  REGISTER_TRACE(pOp->p3, u.co.pDest);
+  UPDATE_MAX_BLOBSIZE(u.co.pDest);
 
-  if( sqlite3VdbeMemTooBig(u.cn.pDest) ){
+  if( sqlite3VdbeMemTooBig(u.co.pDest) ){
     goto too_big;
   }
   break;
@@ -71745,22 +71510,22 @@ case OP_VColumn: {
 ** the end of its result set, then fall through to the next instruction.
 */
 case OP_VNext: {   /* jump */
-#if 0  /* local variables moved into u.co */
+#if 0  /* local variables moved into u.cp */
   sqlite3_vtab *pVtab;
   const sqlite3_module *pModule;
   int res;
   VdbeCursor *pCur;
-#endif /* local variables moved into u.co */
+#endif /* local variables moved into u.cp */
 
-  u.co.res = 0;
-  u.co.pCur = p->apCsr[pOp->p1];
-  assert( u.co.pCur->pVtabCursor );
-  if( u.co.pCur->nullRow ){
+  u.cp.res = 0;
+  u.cp.pCur = p->apCsr[pOp->p1];
+  assert( u.cp.pCur->pVtabCursor );
+  if( u.cp.pCur->nullRow ){
     break;
   }
-  u.co.pVtab = u.co.pCur->pVtabCursor->pVtab;
-  u.co.pModule = u.co.pVtab->pModule;
-  assert( u.co.pModule->xNext );
+  u.cp.pVtab = u.cp.pCur->pVtabCursor->pVtab;
+  u.cp.pModule = u.cp.pVtab->pModule;
+  assert( u.cp.pModule->xNext );
 
   /* Invoke the xNext() method of the module. There is no way for the
   ** underlying implementation to return an error if one occurs during
@@ -71769,18 +71534,18 @@ case OP_VNext: {   /* jump */
   ** some other method is next invoked on the save virtual table cursor.
   */
   p->inVtabMethod = 1;
-  rc = u.co.pModule->xNext(u.co.pCur->pVtabCursor);
+  rc = u.cp.pModule->xNext(u.cp.pCur->pVtabCursor);
   p->inVtabMethod = 0;
-  importVtabErrMsg(p, u.co.pVtab);
+  sqlite3VtabImportErrmsg(p, u.cp.pVtab);
   if( rc==SQLITE_OK ){
-    u.co.res = u.co.pModule->xEof(u.co.pCur->pVtabCursor);
+    u.cp.res = u.cp.pModule->xEof(u.cp.pCur->pVtabCursor);
   }
 
-  if( !u.co.res ){
+  if( !u.cp.res ){
     /* If there is data, jump to P2 */
     pc = pOp->p2 - 1;
   }
-  break;
+  goto check_for_interrupt;
 }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
 
@@ -71792,24 +71557,25 @@ case OP_VNext: {   /* jump */
 ** in register P1 is passed as the zName argument to the xRename method.
 */
 case OP_VRename: {
-#if 0  /* local variables moved into u.cp */
+#if 0  /* local variables moved into u.cq */
   sqlite3_vtab *pVtab;
   Mem *pName;
-#endif /* local variables moved into u.cp */
+#endif /* local variables moved into u.cq */
 
-  u.cp.pVtab = pOp->p4.pVtab->pVtab;
-  u.cp.pName = &aMem[pOp->p1];
-  assert( u.cp.pVtab->pModule->xRename );
-  assert( memIsValid(u.cp.pName) );
-  REGISTER_TRACE(pOp->p1, u.cp.pName);
-  assert( u.cp.pName->flags & MEM_Str );
-  testcase( u.cp.pName->enc==SQLITE_UTF8 );
-  testcase( u.cp.pName->enc==SQLITE_UTF16BE );
-  testcase( u.cp.pName->enc==SQLITE_UTF16LE );
-  rc = sqlite3VdbeChangeEncoding(u.cp.pName, SQLITE_UTF8);
+  u.cq.pVtab = pOp->p4.pVtab->pVtab;
+  u.cq.pName = &aMem[pOp->p1];
+  assert( u.cq.pVtab->pModule->xRename );
+  assert( memIsValid(u.cq.pName) );
+  assert( p->readOnly==0 );
+  REGISTER_TRACE(pOp->p1, u.cq.pName);
+  assert( u.cq.pName->flags & MEM_Str );
+  testcase( u.cq.pName->enc==SQLITE_UTF8 );
+  testcase( u.cq.pName->enc==SQLITE_UTF16BE );
+  testcase( u.cq.pName->enc==SQLITE_UTF16LE );
+  rc = sqlite3VdbeChangeEncoding(u.cq.pName, SQLITE_UTF8);
   if( rc==SQLITE_OK ){
-    rc = u.cp.pVtab->pModule->xRename(u.cp.pVtab, u.cp.pName->z);
-    importVtabErrMsg(p, u.cp.pVtab);
+    rc = u.cq.pVtab->pModule->xRename(u.cq.pVtab, u.cq.pName->z);
+    sqlite3VtabImportErrmsg(p, u.cq.pVtab);
     p->expired = 0;
   }
   break;
@@ -71841,7 +71607,7 @@ case OP_VRename: {
 ** is set to the value of the rowid for the row just inserted.
 */
 case OP_VUpdate: {
-#if 0  /* local variables moved into u.cq */
+#if 0  /* local variables moved into u.cr */
   sqlite3_vtab *pVtab;
   sqlite3_module *pModule;
   int nArg;
@@ -71849,35 +71615,36 @@ case OP_VUpdate: {
   sqlite_int64 rowid;
   Mem **apArg;
   Mem *pX;
-#endif /* local variables moved into u.cq */
+#endif /* local variables moved into u.cr */
 
   assert( pOp->p2==1        || pOp->p5==OE_Fail   || pOp->p5==OE_Rollback
        || pOp->p5==OE_Abort || pOp->p5==OE_Ignore || pOp->p5==OE_Replace
   );
-  u.cq.pVtab = pOp->p4.pVtab->pVtab;
-  u.cq.pModule = (sqlite3_module *)u.cq.pVtab->pModule;
-  u.cq.nArg = pOp->p2;
+  assert( p->readOnly==0 );
+  u.cr.pVtab = pOp->p4.pVtab->pVtab;
+  u.cr.pModule = (sqlite3_module *)u.cr.pVtab->pModule;
+  u.cr.nArg = pOp->p2;
   assert( pOp->p4type==P4_VTAB );
-  if( ALWAYS(u.cq.pModule->xUpdate) ){
+  if( ALWAYS(u.cr.pModule->xUpdate) ){
     u8 vtabOnConflict = db->vtabOnConflict;
-    u.cq.apArg = p->apArg;
-    u.cq.pX = &aMem[pOp->p3];
-    for(u.cq.i=0; u.cq.i<u.cq.nArg; u.cq.i++){
-      assert( memIsValid(u.cq.pX) );
-      memAboutToChange(p, u.cq.pX);
-      sqlite3VdbeMemStoreType(u.cq.pX);
-      u.cq.apArg[u.cq.i] = u.cq.pX;
-      u.cq.pX++;
+    u.cr.apArg = p->apArg;
+    u.cr.pX = &aMem[pOp->p3];
+    for(u.cr.i=0; u.cr.i<u.cr.nArg; u.cr.i++){
+      assert( memIsValid(u.cr.pX) );
+      memAboutToChange(p, u.cr.pX);
+      sqlite3VdbeMemStoreType(u.cr.pX);
+      u.cr.apArg[u.cr.i] = u.cr.pX;
+      u.cr.pX++;
     }
     db->vtabOnConflict = pOp->p5;
-    rc = u.cq.pModule->xUpdate(u.cq.pVtab, u.cq.nArg, u.cq.apArg, &u.cq.rowid);
+    rc = u.cr.pModule->xUpdate(u.cr.pVtab, u.cr.nArg, u.cr.apArg, &u.cr.rowid);
     db->vtabOnConflict = vtabOnConflict;
-    importVtabErrMsg(p, u.cq.pVtab);
+    sqlite3VtabImportErrmsg(p, u.cr.pVtab);
     if( rc==SQLITE_OK && pOp->p1 ){
-      assert( u.cq.nArg>1 && u.cq.apArg[0] && (u.cq.apArg[0]->flags&MEM_Null) );
-      db->lastRowid = lastRowid = u.cq.rowid;
+      assert( u.cr.nArg>1 && u.cr.apArg[0] && (u.cr.apArg[0]->flags&MEM_Null) );
+      db->lastRowid = lastRowid = u.cr.rowid;
     }
-    if( rc==SQLITE_CONSTRAINT && pOp->p4.pVtab->bConstraint ){
+    if( (rc&0xff)==SQLITE_CONSTRAINT && pOp->p4.pVtab->bConstraint ){
       if( pOp->p5==OE_Ignore ){
         rc = SQLITE_OK;
       }else{
@@ -71935,21 +71702,24 @@ case OP_MaxPgcnt: {            /* out2-prerelease */
 ** the UTF-8 string contained in P4 is emitted on the trace callback.
 */
 case OP_Trace: {
-#if 0  /* local variables moved into u.cr */
+#if 0  /* local variables moved into u.cs */
   char *zTrace;
   char *z;
-#endif /* local variables moved into u.cr */
+#endif /* local variables moved into u.cs */
 
-  if( db->xTrace && (u.cr.zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql))!=0 ){
-    u.cr.z = sqlite3VdbeExpandSql(p, u.cr.zTrace);
-    db->xTrace(db->pTraceArg, u.cr.z);
-    sqlite3DbFree(db, u.cr.z);
+  if( db->xTrace
+   && !p->doingRerun
+   && (u.cs.zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql))!=0
+  ){
+    u.cs.z = sqlite3VdbeExpandSql(p, u.cs.zTrace);
+    db->xTrace(db->pTraceArg, u.cs.z);
+    sqlite3DbFree(db, u.cs.z);
   }
 #ifdef SQLITE_DEBUG
   if( (db->flags & SQLITE_SqlTrace)!=0
-   && (u.cr.zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql))!=0
+   && (u.cs.zTrace = (pOp->p4.z ? pOp->p4.z : p->zSql))!=0
   ){
-    sqlite3DebugPrintf("SQL-trace: %s\n", u.cr.zTrace);
+    sqlite3DebugPrintf("SQL-trace: %s\n", u.cs.zTrace);
   }
 #endif /* SQLITE_DEBUG */
   break;
@@ -72036,6 +71806,8 @@ vdbe_error_halt:
   ** top. */
 vdbe_return:
   db->lastRowid = lastRowid;
+  testcase( nVmStep>0 );
+  p->aCounter[SQLITE_STMTSTATUS_VM_STEP] += (int)nVmStep;
   sqlite3VdbeLeave(p);
   return rc;
 
@@ -72392,7 +72164,7 @@ SQLITE_API int sqlite3_blob_open(
     }
     sqlite3_bind_int64(pBlob->pStmt, 1, iRow);
     rc = blobSeekToRow(pBlob, iRow, &zErr);
-  } while( (++nAttempt)<5 && rc==SQLITE_SCHEMA );
+  } while( (++nAttempt)<SQLITE_MAX_SCHEMA_RETRY && rc==SQLITE_SCHEMA );
 
 blob_open_out:
   if( rc==SQLITE_OK && db->mallocFailed==0 ){
@@ -72567,10 +72339,10 @@ SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *pBlob, sqlite3_int64 iRow){
 */
 
 
-#ifndef SQLITE_OMIT_MERGE_SORT
 
 typedef struct VdbeSorterIter VdbeSorterIter;
 typedef struct SorterRecord SorterRecord;
+typedef struct FileWriter FileWriter;
 
 /*
 ** NOTES ON DATA STRUCTURE USED FOR N-WAY MERGES:
@@ -72603,7 +72375,7 @@ typedef struct SorterRecord SorterRecord;
 ** other key value. If the keys are equal (only possible with two EOF
 ** values), it doesn't matter which index is stored.
 **
-** The (N/4) elements of aTree[] that preceed the final (N/2) described 
+** The (N/4) elements of aTree[] that precede the final (N/2) described 
 ** above contains the index of the smallest of each block of 4 iterators.
 ** And so on. So that aTree[1] contains the index of the iterator that 
 ** currently points to the smallest key value. aTree[0] is unused.
@@ -72668,6 +72440,24 @@ struct VdbeSorterIter {
   sqlite3_file *pFile;            /* File iterator is reading from */
   u8 *aAlloc;                     /* Allocated space */
   u8 *aKey;                       /* Pointer to current key */
+  u8 *aBuffer;                    /* Current read buffer */
+  int nBuffer;                    /* Size of read buffer in bytes */
+};
+
+/*
+** An instance of this structure is used to organize the stream of records
+** being written to files by the merge-sort code into aligned, page-sized
+** blocks.  Doing all I/O in aligned page-sized blocks helps I/O to go
+** faster on many operating systems.
+*/
+struct FileWriter {
+  int eFWErr;                     /* Non-zero if in an error state */
+  u8 *aBuffer;                    /* Pointer to write buffer */
+  int nBuffer;                    /* Size of write buffer in bytes */
+  int iBufStart;                  /* First byte of buffer to write */
+  int iBufEnd;                    /* Last byte of buffer to write */
+  i64 iWriteOff;                  /* Offset of start of buffer in file */
+  sqlite3_file *pFile;            /* File to write to */
 };
 
 /*
@@ -72693,9 +72483,126 @@ struct SorterRecord {
 */
 static void vdbeSorterIterZero(sqlite3 *db, VdbeSorterIter *pIter){
   sqlite3DbFree(db, pIter->aAlloc);
+  sqlite3DbFree(db, pIter->aBuffer);
   memset(pIter, 0, sizeof(VdbeSorterIter));
 }
 
+/*
+** Read nByte bytes of data from the stream of data iterated by object p.
+** If successful, set *ppOut to point to a buffer containing the data
+** and return SQLITE_OK. Otherwise, if an error occurs, return an SQLite
+** error code.
+**
+** The buffer indicated by *ppOut may only be considered valid until the
+** next call to this function.
+*/
+static int vdbeSorterIterRead(
+  sqlite3 *db,                    /* Database handle (for malloc) */
+  VdbeSorterIter *p,              /* Iterator */
+  int nByte,                      /* Bytes of data to read */
+  u8 **ppOut                      /* OUT: Pointer to buffer containing data */
+){
+  int iBuf;                       /* Offset within buffer to read from */
+  int nAvail;                     /* Bytes of data available in buffer */
+  assert( p->aBuffer );
+
+  /* If there is no more data to be read from the buffer, read the next 
+  ** p->nBuffer bytes of data from the file into it. Or, if there are less
+  ** than p->nBuffer bytes remaining in the PMA, read all remaining data.  */
+  iBuf = p->iReadOff % p->nBuffer;
+  if( iBuf==0 ){
+    int nRead;                    /* Bytes to read from disk */
+    int rc;                       /* sqlite3OsRead() return code */
+
+    /* Determine how many bytes of data to read. */
+    if( (p->iEof - p->iReadOff) > (i64)p->nBuffer ){
+      nRead = p->nBuffer;
+    }else{
+      nRead = (int)(p->iEof - p->iReadOff);
+    }
+    assert( nRead>0 );
+
+    /* Read data from the file. Return early if an error occurs. */
+    rc = sqlite3OsRead(p->pFile, p->aBuffer, nRead, p->iReadOff);
+    assert( rc!=SQLITE_IOERR_SHORT_READ );
+    if( rc!=SQLITE_OK ) return rc;
+  }
+  nAvail = p->nBuffer - iBuf; 
+
+  if( nByte<=nAvail ){
+    /* The requested data is available in the in-memory buffer. In this
+    ** case there is no need to make a copy of the data, just return a 
+    ** pointer into the buffer to the caller.  */
+    *ppOut = &p->aBuffer[iBuf];
+    p->iReadOff += nByte;
+  }else{
+    /* The requested data is not all available in the in-memory buffer.
+    ** In this case, allocate space at p->aAlloc[] to copy the requested
+    ** range into. Then return a copy of pointer p->aAlloc to the caller.  */
+    int nRem;                     /* Bytes remaining to copy */
+
+    /* Extend the p->aAlloc[] allocation if required. */
+    if( p->nAlloc<nByte ){
+      int nNew = p->nAlloc*2;
+      while( nByte>nNew ) nNew = nNew*2;
+      p->aAlloc = sqlite3DbReallocOrFree(db, p->aAlloc, nNew);
+      if( !p->aAlloc ) return SQLITE_NOMEM;
+      p->nAlloc = nNew;
+    }
+
+    /* Copy as much data as is available in the buffer into the start of
+    ** p->aAlloc[].  */
+    memcpy(p->aAlloc, &p->aBuffer[iBuf], nAvail);
+    p->iReadOff += nAvail;
+    nRem = nByte - nAvail;
+
+    /* The following loop copies up to p->nBuffer bytes per iteration into
+    ** the p->aAlloc[] buffer.  */
+    while( nRem>0 ){
+      int rc;                     /* vdbeSorterIterRead() return code */
+      int nCopy;                  /* Number of bytes to copy */
+      u8 *aNext;                  /* Pointer to buffer to copy data from */
+
+      nCopy = nRem;
+      if( nRem>p->nBuffer ) nCopy = p->nBuffer;
+      rc = vdbeSorterIterRead(db, p, nCopy, &aNext);
+      if( rc!=SQLITE_OK ) return rc;
+      assert( aNext!=p->aAlloc );
+      memcpy(&p->aAlloc[nByte - nRem], aNext, nCopy);
+      nRem -= nCopy;
+    }
+
+    *ppOut = p->aAlloc;
+  }
+
+  return SQLITE_OK;
+}
+
+/*
+** Read a varint from the stream of data accessed by p. Set *pnOut to
+** the value read.
+*/
+static int vdbeSorterIterVarint(sqlite3 *db, VdbeSorterIter *p, u64 *pnOut){
+  int iBuf;
+
+  iBuf = p->iReadOff % p->nBuffer;
+  if( iBuf && (p->nBuffer-iBuf)>=9 ){
+    p->iReadOff += sqlite3GetVarint(&p->aBuffer[iBuf], pnOut);
+  }else{
+    u8 aVarint[16], *a;
+    int i = 0, rc;
+    do{
+      rc = vdbeSorterIterRead(db, p, 1, &a);
+      if( rc ) return rc;
+      aVarint[(i++)&0xf] = a[0];
+    }while( (a[0]&0x80)!=0 );
+    sqlite3GetVarint(aVarint, pnOut);
+  }
+
+  return SQLITE_OK;
+}
+
+
 /*
 ** Advance iterator pIter to the next key in its PMA. Return SQLITE_OK if
 ** no error occurs, or an SQLite error code if one does.
@@ -72705,96 +72612,18 @@ static int vdbeSorterIterNext(
   VdbeSorterIter *pIter           /* Iterator to advance */
 ){
   int rc;                         /* Return Code */
-  int nRead;                      /* Number of bytes read */
-  int nRec = 0;                   /* Size of record in bytes */
-  int iOff = 0;                   /* Size of serialized size varint in bytes */
+  u64 nRec = 0;                   /* Size of record in bytes */
 
-  assert( pIter->iEof>=pIter->iReadOff );
-  if( pIter->iEof-pIter->iReadOff>5 ){
-    nRead = 5;
-  }else{
-    nRead = (int)(pIter->iEof - pIter->iReadOff);
-  }
-  if( nRead<=0 ){
+  if( pIter->iReadOff>=pIter->iEof ){
     /* This is an EOF condition */
     vdbeSorterIterZero(db, pIter);
     return SQLITE_OK;
   }
 
-  rc = sqlite3OsRead(pIter->pFile, pIter->aAlloc, nRead, pIter->iReadOff);
+  rc = vdbeSorterIterVarint(db, pIter, &nRec);
   if( rc==SQLITE_OK ){
-    iOff = getVarint32(pIter->aAlloc, nRec);
-    if( (iOff+nRec)>nRead ){
-      int nRead2;                   /* Number of extra bytes to read */
-      if( (iOff+nRec)>pIter->nAlloc ){
-        int nNew = pIter->nAlloc*2;
-        while( (iOff+nRec)>nNew ) nNew = nNew*2;
-        pIter->aAlloc = sqlite3DbReallocOrFree(db, pIter->aAlloc, nNew);
-        if( !pIter->aAlloc ) return SQLITE_NOMEM;
-        pIter->nAlloc = nNew;
-      }
-  
-      nRead2 = iOff + nRec - nRead;
-      rc = sqlite3OsRead(
-          pIter->pFile, &pIter->aAlloc[nRead], nRead2, pIter->iReadOff+nRead
-      );
-    }
-  }
-
-  assert( rc!=SQLITE_OK || nRec>0 );
-  pIter->iReadOff += iOff+nRec;
-  pIter->nKey = nRec;
-  pIter->aKey = &pIter->aAlloc[iOff];
-  return rc;
-}
-
-/*
-** Write a single varint, value iVal, to file-descriptor pFile. Return
-** SQLITE_OK if successful, or an SQLite error code if some error occurs.
-**
-** The value of *piOffset when this function is called is used as the byte
-** offset in file pFile to write to. Before returning, *piOffset is 
-** incremented by the number of bytes written.
-*/
-static int vdbeSorterWriteVarint(
-  sqlite3_file *pFile,            /* File to write to */
-  i64 iVal,                       /* Value to write as a varint */
-  i64 *piOffset                   /* IN/OUT: Write offset in file pFile */
-){
-  u8 aVarint[9];                  /* Buffer large enough for a varint */
-  int nVarint;                    /* Number of used bytes in varint */
-  int rc;                         /* Result of write() call */
-
-  nVarint = sqlite3PutVarint(aVarint, iVal);
-  rc = sqlite3OsWrite(pFile, aVarint, nVarint, *piOffset);
-  *piOffset += nVarint;
-
-  return rc;
-}
-
-/*
-** Read a single varint from file-descriptor pFile. Return SQLITE_OK if
-** successful, or an SQLite error code if some error occurs.
-**
-** The value of *piOffset when this function is called is used as the
-** byte offset in file pFile from whence to read the varint. If successful
-** (i.e. if no IO error occurs), then *piOffset is set to the offset of
-** the first byte past the end of the varint before returning. *piVal is
-** set to the integer value read. If an error occurs, the final values of
-** both *piOffset and *piVal are undefined.
-*/
-static int vdbeSorterReadVarint(
-  sqlite3_file *pFile,            /* File to read from */
-  i64 *piOffset,                  /* IN/OUT: Read offset in pFile */
-  i64 *piVal                      /* OUT: Value read from file */
-){
-  u8 aVarint[9];                  /* Buffer large enough for a varint */
-  i64 iOff = *piOffset;           /* Offset in file to read from */
-  int rc;                         /* Return code */
-
-  rc = sqlite3OsRead(pFile, aVarint, 9, iOff);
-  if( rc==SQLITE_OK ){
-    *piOffset += getVarint(aVarint, (u64 *)piVal);
+    pIter->nKey = (int)nRec;
+    rc = vdbeSorterIterRead(db, pIter, (int)nRec, &pIter->aKey);
   }
 
   return rc;
@@ -72808,27 +72637,52 @@ static int vdbeSorterReadVarint(
 */
 static int vdbeSorterIterInit(
   sqlite3 *db,                    /* Database handle */
-  VdbeSorter *pSorter,            /* Sorter object */
+  const VdbeSorter *pSorter,      /* Sorter object */
   i64 iStart,                     /* Start offset in pFile */
   VdbeSorterIter *pIter,          /* Iterator to populate */
   i64 *pnByte                     /* IN/OUT: Increment this value by PMA size */
 ){
-  int rc;
+  int rc = SQLITE_OK;
+  int nBuf;
+
+  nBuf = sqlite3BtreeGetPageSize(db->aDb[0].pBt);
 
   assert( pSorter->iWriteOff>iStart );
   assert( pIter->aAlloc==0 );
+  assert( pIter->aBuffer==0 );
   pIter->pFile = pSorter->pTemp1;
   pIter->iReadOff = iStart;
   pIter->nAlloc = 128;
   pIter->aAlloc = (u8 *)sqlite3DbMallocRaw(db, pIter->nAlloc);
-  if( !pIter->aAlloc ){
+  pIter->nBuffer = nBuf;
+  pIter->aBuffer = (u8 *)sqlite3DbMallocRaw(db, nBuf);
+
+  if( !pIter->aBuffer ){
     rc = SQLITE_NOMEM;
   }else{
-    i64 nByte;                         /* Total size of PMA in bytes */
-    rc = vdbeSorterReadVarint(pSorter->pTemp1, &pIter->iReadOff, &nByte);
-    *pnByte += nByte;
-    pIter->iEof = pIter->iReadOff + nByte;
+    int iBuf;
+
+    iBuf = iStart % nBuf;
+    if( iBuf ){
+      int nRead = nBuf - iBuf;
+      if( (iStart + nRead) > pSorter->iWriteOff ){
+        nRead = (int)(pSorter->iWriteOff - iStart);
+      }
+      rc = sqlite3OsRead(
+          pSorter->pTemp1, &pIter->aBuffer[iBuf], nRead, iStart
+      );
+      assert( rc!=SQLITE_IOERR_SHORT_READ );
+    }
+
+    if( rc==SQLITE_OK ){
+      u64 nByte;                       /* Size of PMA in bytes */
+      pIter->iEof = pSorter->iWriteOff;
+      rc = vdbeSorterIterVarint(db, pIter, &nByte);
+      pIter->iEof = pIter->iReadOff + nByte;
+      *pnByte += nByte;
+    }
   }
+
   if( rc==SQLITE_OK ){
     rc = vdbeSorterIterNext(db, pIter);
   }
@@ -72852,10 +72706,10 @@ static int vdbeSorterIterInit(
 ** has been allocated and contains an unpacked record that is used as key2.
 */
 static void vdbeSorterCompare(
-  VdbeCursor *pCsr,               /* Cursor object (for pKeyInfo) */
+  const VdbeCursor *pCsr,         /* Cursor object (for pKeyInfo) */
   int bOmitRowid,                 /* Ignore rowid field at end of keys */
-  void *pKey1, int nKey1,         /* Left side of comparison */
-  void *pKey2, int nKey2,         /* Right side of comparison */
+  const void *pKey1, int nKey1,   /* Left side of comparison */
+  const void *pKey2, int nKey2,   /* Right side of comparison */
   int *pRes                       /* OUT: Result of comparison */
 ){
   KeyInfo *pKeyInfo = pCsr->pKeyInfo;
@@ -72887,7 +72741,7 @@ static void vdbeSorterCompare(
 ** multiple b-tree segments. Parameter iOut is the index of the aTree[] 
 ** value to recalculate.
 */
-static int vdbeSorterDoCompare(VdbeCursor *pCsr, int iOut){
+static int vdbeSorterDoCompare(const VdbeCursor *pCsr, int iOut){
   VdbeSorter *pSorter = pCsr->pSorter;
   int i1;
   int i2;
@@ -73013,7 +72867,7 @@ static int vdbeSorterOpenTempFile(sqlite3 *db, sqlite3_file **ppFile){
 ** Set *ppOut to the head of the new list.
 */
 static void vdbeSorterMerge(
-  VdbeCursor *pCsr,               /* For pKeyInfo */
+  const VdbeCursor *pCsr,         /* For pKeyInfo */
   SorterRecord *p1,               /* First list to merge */
   SorterRecord *p2,               /* Second list to merge */
   SorterRecord **ppOut            /* OUT: Head of merged list */
@@ -73047,7 +72901,7 @@ static void vdbeSorterMerge(
 ** if successful, or an SQLite error code (i.e. SQLITE_NOMEM) if an error
 ** occurs.
 */
-static int vdbeSorterSort(VdbeCursor *pCsr){
+static int vdbeSorterSort(const VdbeCursor *pCsr){
   int i;
   SorterRecord **aSlot;
   SorterRecord *p;
@@ -73080,6 +72934,91 @@ static int vdbeSorterSort(VdbeCursor *pCsr){
   return SQLITE_OK;
 }
 
+/*
+** Initialize a file-writer object.
+*/
+static void fileWriterInit(
+  sqlite3 *db,                    /* Database (for malloc) */
+  sqlite3_file *pFile,            /* File to write to */
+  FileWriter *p,                  /* Object to populate */
+  i64 iStart                      /* Offset of pFile to begin writing at */
+){
+  int nBuf = sqlite3BtreeGetPageSize(db->aDb[0].pBt);
+
+  memset(p, 0, sizeof(FileWriter));
+  p->aBuffer = (u8 *)sqlite3DbMallocRaw(db, nBuf);
+  if( !p->aBuffer ){
+    p->eFWErr = SQLITE_NOMEM;
+  }else{
+    p->iBufEnd = p->iBufStart = (iStart % nBuf);
+    p->iWriteOff = iStart - p->iBufStart;
+    p->nBuffer = nBuf;
+    p->pFile = pFile;
+  }
+}
+
+/*
+** Write nData bytes of data to the file-write object. Return SQLITE_OK
+** if successful, or an SQLite error code if an error occurs.
+*/
+static void fileWriterWrite(FileWriter *p, u8 *pData, int nData){
+  int nRem = nData;
+  while( nRem>0 && p->eFWErr==0 ){
+    int nCopy = nRem;
+    if( nCopy>(p->nBuffer - p->iBufEnd) ){
+      nCopy = p->nBuffer - p->iBufEnd;
+    }
+
+    memcpy(&p->aBuffer[p->iBufEnd], &pData[nData-nRem], nCopy);
+    p->iBufEnd += nCopy;
+    if( p->iBufEnd==p->nBuffer ){
+      p->eFWErr = sqlite3OsWrite(p->pFile, 
+          &p->aBuffer[p->iBufStart], p->iBufEnd - p->iBufStart, 
+          p->iWriteOff + p->iBufStart
+      );
+      p->iBufStart = p->iBufEnd = 0;
+      p->iWriteOff += p->nBuffer;
+    }
+    assert( p->iBufEnd<p->nBuffer );
+
+    nRem -= nCopy;
+  }
+}
+
+/*
+** Flush any buffered data to disk and clean up the file-writer object.
+** The results of using the file-writer after this call are undefined.
+** Return SQLITE_OK if flushing the buffered data succeeds or is not 
+** required. Otherwise, return an SQLite error code.
+**
+** Before returning, set *piEof to the offset immediately following the
+** last byte written to the file.
+*/
+static int fileWriterFinish(sqlite3 *db, FileWriter *p, i64 *piEof){
+  int rc;
+  if( p->eFWErr==0 && ALWAYS(p->aBuffer) && p->iBufEnd>p->iBufStart ){
+    p->eFWErr = sqlite3OsWrite(p->pFile, 
+        &p->aBuffer[p->iBufStart], p->iBufEnd - p->iBufStart, 
+        p->iWriteOff + p->iBufStart
+    );
+  }
+  *piEof = (p->iWriteOff + p->iBufEnd);
+  sqlite3DbFree(db, p->aBuffer);
+  rc = p->eFWErr;
+  memset(p, 0, sizeof(FileWriter));
+  return rc;
+}
+
+/*
+** Write value iVal encoded as a varint to the file-write object. Return 
+** SQLITE_OK if successful, or an SQLite error code if an error occurs.
+*/
+static void fileWriterWriteVarint(FileWriter *p, u64 iVal){
+  int nByte; 
+  u8 aByte[10];
+  nByte = sqlite3PutVarint(aByte, iVal);
+  fileWriterWrite(p, aByte, nByte);
+}
 
 /*
 ** Write the current contents of the in-memory linked-list to a PMA. Return
@@ -73094,9 +73033,12 @@ static int vdbeSorterSort(VdbeCursor *pCsr){
 **       Each record consists of a varint followed by a blob of data (the 
 **       key). The varint is the number of bytes in the blob of data.
 */
-static int vdbeSorterListToPMA(sqlite3 *db, VdbeCursor *pCsr){
+static int vdbeSorterListToPMA(sqlite3 *db, const VdbeCursor *pCsr){
   int rc = SQLITE_OK;             /* Return code */
   VdbeSorter *pSorter = pCsr->pSorter;
+  FileWriter writer;
+
+  memset(&writer, 0, sizeof(FileWriter));
 
   if( pSorter->nInMemory==0 ){
     assert( pSorter->pRecord==0 );
@@ -73114,39 +73056,20 @@ static int vdbeSorterListToPMA(sqlite3 *db, VdbeCursor *pCsr){
   }
 
   if( rc==SQLITE_OK ){
-    i64 iOff = pSorter->iWriteOff;
     SorterRecord *p;
     SorterRecord *pNext = 0;
-    static const char eightZeros[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
 
+    fileWriterInit(db, pSorter->pTemp1, &writer, pSorter->iWriteOff);
     pSorter->nPMA++;
-    rc = vdbeSorterWriteVarint(pSorter->pTemp1, pSorter->nInMemory, &iOff);
-    for(p=pSorter->pRecord; rc==SQLITE_OK && p; p=pNext){
+    fileWriterWriteVarint(&writer, pSorter->nInMemory);
+    for(p=pSorter->pRecord; p; p=pNext){
       pNext = p->pNext;
-      rc = vdbeSorterWriteVarint(pSorter->pTemp1, p->nVal, &iOff);
-
-      if( rc==SQLITE_OK ){
-        rc = sqlite3OsWrite(pSorter->pTemp1, p->pVal, p->nVal, iOff);
-        iOff += p->nVal;
-      }
-
+      fileWriterWriteVarint(&writer, p->nVal);
+      fileWriterWrite(&writer, p->pVal, p->nVal);
       sqlite3DbFree(db, p);
     }
-
-    /* This assert verifies that unless an error has occurred, the size of 
-    ** the PMA on disk is the same as the expected size stored in
-    ** pSorter->nInMemory. */ 
-    assert( rc!=SQLITE_OK || pSorter->nInMemory==(
-          iOff-pSorter->iWriteOff-sqlite3VarintLen(pSorter->nInMemory)
-    ));
-
-    pSorter->iWriteOff = iOff;
-    if( rc==SQLITE_OK ){
-      /* Terminate each file with 8 extra bytes so that from any offset
-      ** in the file we can always read 9 bytes without a SHORT_READ error */
-      rc = sqlite3OsWrite(pSorter->pTemp1, eightZeros, 8, iOff);
-    }
     pSorter->pRecord = p;
+    rc = fileWriterFinish(db, &writer, &pSorter->iWriteOff);
   }
 
   return rc;
@@ -73157,7 +73080,7 @@ static int vdbeSorterListToPMA(sqlite3 *db, VdbeCursor *pCsr){
 */
 SQLITE_PRIVATE int sqlite3VdbeSorterWrite(
   sqlite3 *db,                    /* Database handle */
-  VdbeCursor *pCsr,               /* Sorter cursor */
+  const VdbeCursor *pCsr,               /* Sorter cursor */
   Mem *pVal                       /* Memory cell containing record */
 ){
   VdbeSorter *pSorter = pCsr->pSorter;
@@ -73191,8 +73114,14 @@ SQLITE_PRIVATE int sqlite3VdbeSorterWrite(
         (pSorter->nInMemory>pSorter->mxPmaSize)
      || (pSorter->nInMemory>pSorter->mnPmaSize && sqlite3HeapNearlyFull())
   )){
+#ifdef SQLITE_DEBUG
+    i64 nExpect = pSorter->iWriteOff
+                + sqlite3VarintLen(pSorter->nInMemory)
+                + pSorter->nInMemory;
+#endif
     rc = vdbeSorterListToPMA(db, pCsr);
     pSorter->nInMemory = 0;
+    assert( rc!=SQLITE_OK || (nExpect==pSorter->iWriteOff) );
   }
 
   return rc;
@@ -73203,7 +73132,7 @@ SQLITE_PRIVATE int sqlite3VdbeSorterWrite(
 */
 static int vdbeSorterInitMerge(
   sqlite3 *db,                    /* Database handle */
-  VdbeCursor *pCsr,               /* Cursor handle for this sorter */
+  const VdbeCursor *pCsr,         /* Cursor handle for this sorter */
   i64 *pnByte                     /* Sum of bytes in all opened PMAs */
 ){
   VdbeSorter *pSorter = pCsr->pSorter;
@@ -73233,7 +73162,7 @@ static int vdbeSorterInitMerge(
 ** Once the sorter has been populated, this function is called to prepare
 ** for iterating through its contents in sorted order.
 */
-SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *db, VdbeCursor *pCsr, int *pbEof){
+SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *db, const VdbeCursor *pCsr, int *pbEof){
   VdbeSorter *pSorter = pCsr->pSorter;
   int rc;                         /* Return code */
   sqlite3_file *pTemp2 = 0;       /* Second temp file to use */
@@ -73253,7 +73182,7 @@ SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *db, VdbeCursor *pCsr, int *p
     return vdbeSorterSort(pCsr);
   }
 
-  /* Write the current b-tree to a PMA. Close the b-tree cursor. */
+  /* Write the current in-memory list to a PMA. */
   rc = vdbeSorterListToPMA(db, pCsr);
   if( rc!=SQLITE_OK ) return rc;
 
@@ -73275,8 +73204,12 @@ SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *db, VdbeCursor *pCsr, int *p
         rc==SQLITE_OK && iNew*SORTER_MAX_MERGE_COUNT<pSorter->nPMA; 
         iNew++
     ){
+      int rc2;                    /* Return code from fileWriterFinish() */
+      FileWriter writer;          /* Object used to write to disk */
       i64 nWrite;                 /* Number of bytes in new PMA */
 
+      memset(&writer, 0, sizeof(FileWriter));
+
       /* If there are SORTER_MAX_MERGE_COUNT or less PMAs in file pTemp1,
       ** initialize an iterator for each of them and break out of the loop.
       ** These iterators will be incrementally merged as the VDBE layer calls
@@ -73298,23 +73231,20 @@ SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *db, VdbeCursor *pCsr, int *p
         rc = vdbeSorterOpenTempFile(db, &pTemp2);
       }
 
-      if( rc==SQLITE_OK ){
-        rc = vdbeSorterWriteVarint(pTemp2, nWrite, &iWrite2);
-      }
-
       if( rc==SQLITE_OK ){
         int bEof = 0;
+        fileWriterInit(db, pTemp2, &writer, iWrite2);
+        fileWriterWriteVarint(&writer, nWrite);
         while( rc==SQLITE_OK && bEof==0 ){
-          int nToWrite;
           VdbeSorterIter *pIter = &pSorter->aIter[ pSorter->aTree[1] ];
           assert( pIter->pFile );
-          nToWrite = pIter->nKey + sqlite3VarintLen(pIter->nKey);
-          rc = sqlite3OsWrite(pTemp2, pIter->aAlloc, nToWrite, iWrite2);
-          iWrite2 += nToWrite;
-          if( rc==SQLITE_OK ){
-            rc = sqlite3VdbeSorterNext(db, pCsr, &bEof);
-          }
+
+          fileWriterWriteVarint(&writer, pIter->nKey);
+          fileWriterWrite(&writer, pIter->aKey, pIter->nKey);
+          rc = sqlite3VdbeSorterNext(db, pCsr, &bEof);
         }
+        rc2 = fileWriterFinish(db, &writer, &iWrite2);
+        if( rc==SQLITE_OK ) rc = rc2;
       }
     }
 
@@ -73341,7 +73271,7 @@ SQLITE_PRIVATE int sqlite3VdbeSorterRewind(sqlite3 *db, VdbeCursor *pCsr, int *p
 /*
 ** Advance to the next element in the sorter.
 */
-SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *db, VdbeCursor *pCsr, int *pbEof){
+SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *db, const VdbeCursor *pCsr, int *pbEof){
   VdbeSorter *pSorter = pCsr->pSorter;
   int rc;                         /* Return code */
 
@@ -73371,7 +73301,7 @@ SQLITE_PRIVATE int sqlite3VdbeSorterNext(sqlite3 *db, VdbeCursor *pCsr, int *pbE
 ** current key.
 */
 static void *vdbeSorterRowkey(
-  VdbeSorter *pSorter,            /* Sorter object */
+  const VdbeSorter *pSorter,      /* Sorter object */
   int *pnKey                      /* OUT: Size of current key in bytes */
 ){
   void *pKey;
@@ -73390,7 +73320,7 @@ static void *vdbeSorterRowkey(
 /*
 ** Copy the current sorter key into the memory cell pOut.
 */
-SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(VdbeCursor *pCsr, Mem *pOut){
+SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(const VdbeCursor *pCsr, Mem *pOut){
   VdbeSorter *pSorter = pCsr->pSorter;
   void *pKey; int nKey;           /* Sorter key to copy into pOut */
 
@@ -73416,7 +73346,7 @@ SQLITE_PRIVATE int sqlite3VdbeSorterRowkey(VdbeCursor *pCsr, Mem *pOut){
 ** key.
 */
 SQLITE_PRIVATE int sqlite3VdbeSorterCompare(
-  VdbeCursor *pCsr,               /* Sorter cursor */
+  const VdbeCursor *pCsr,         /* Sorter cursor */
   Mem *pVal,                      /* Value to compare to current sorter key */
   int *pRes                       /* OUT: Result of comparison */
 ){
@@ -73428,8 +73358,6 @@ SQLITE_PRIVATE int sqlite3VdbeSorterCompare(
   return SQLITE_OK;
 }
 
-#endif /* #ifndef SQLITE_OMIT_MERGE_SORT */
-
 /************** End of vdbesort.c ********************************************/
 /************** Begin file journal.c *****************************************/
 /*
@@ -73492,6 +73420,14 @@ static int createFile(JournalFile *p){
         assert(p->iSize<=p->nBuf);
         rc = sqlite3OsWrite(p->pReal, p->zBuf, p->iSize, 0);
       }
+      if( rc!=SQLITE_OK ){
+        /* If an error occurred while writing to the file, close it before
+        ** returning. This way, SQLite uses the in-memory journal data to 
+        ** roll back changes made to the internal page-cache before this
+        ** function was called.  */
+        sqlite3OsClose(pReal);
+        p->pReal = 0;
+      }
     }
   }
   return rc;
@@ -73661,6 +73597,16 @@ SQLITE_PRIVATE int sqlite3JournalCreate(sqlite3_file *p){
   return createFile((JournalFile *)p);
 }
 
+/*
+** The file-handle passed as the only argument is guaranteed to be an open
+** file. It may or may not be of class JournalFile. If the file is a
+** JournalFile, and the underlying file on disk has not yet been opened,
+** return 0. Otherwise, return 1.
+*/
+SQLITE_PRIVATE int sqlite3JournalExists(sqlite3_file *p){
+  return (p->pMethods!=&JournalFileMethods || ((JournalFile *)p)->pReal!=0);
+}
+
 /* 
 ** Return the number of bytes required to store a JournalFile that uses vfs
 ** pVfs to create the underlying on-disk files.
@@ -73704,12 +73650,6 @@ typedef struct FileChunk FileChunk;
 */
 #define JOURNAL_CHUNKSIZE ((int)(1024-sizeof(FileChunk*)))
 
-/* Macro to find the minimum of two numeric values.
-*/
-#ifndef MIN
-# define MIN(x,y) ((x)<(y)?(x):(y))
-#endif
-
 /*
 ** The rollback journal is composed of a linked list of these structures.
 */
@@ -73903,7 +73843,9 @@ static const struct sqlite3_io_methods MemJournalMethods = {
   0,                /* xShmMap */
   0,                /* xShmLock */
   0,                /* xShmBarrier */
-  0                 /* xShmUnlock */
+  0,                /* xShmUnmap */
+  0,                /* xFetch */
+  0                 /* xUnfetch */
 };
 
 /* 
@@ -74047,7 +73989,9 @@ SQLITE_PRIVATE int sqlite3WalkSelectFrom(Walker *pWalker, Select *p){
 /*
 ** Call sqlite3WalkExpr() for every expression in Select statement p.
 ** Invoke sqlite3WalkSelect() for subqueries in the FROM clause and
-** on the compound select chain, p->pPrior.
+** on the compound select chain, p->pPrior.  Invoke the xSelectCallback()
+** either before or after the walk of expressions and FROM clause, depending
+** on whether pWalker->bSelectDepthFirst is false or true, respectively.
 **
 ** Return WRC_Continue under normal conditions.  Return WRC_Abort if
 ** there is an abort request.
@@ -74059,13 +74003,28 @@ SQLITE_PRIVATE int sqlite3WalkSelect(Walker *pWalker, Select *p){
   int rc;
   if( p==0 || pWalker->xSelectCallback==0 ) return WRC_Continue;
   rc = WRC_Continue;
-  while( p  ){
-    rc = pWalker->xSelectCallback(pWalker, p);
-    if( rc ) break;
-    if( sqlite3WalkSelectExpr(pWalker, p) ) return WRC_Abort;
-    if( sqlite3WalkSelectFrom(pWalker, p) ) return WRC_Abort;
+  pWalker->walkerDepth++;
+  while( p ){
+    if( !pWalker->bSelectDepthFirst ){
+       rc = pWalker->xSelectCallback(pWalker, p);
+       if( rc ) break;
+    }
+    if( sqlite3WalkSelectExpr(pWalker, p)
+     || sqlite3WalkSelectFrom(pWalker, p)
+    ){
+      pWalker->walkerDepth--;
+      return WRC_Abort;
+    }
+    if( pWalker->bSelectDepthFirst ){
+      rc = pWalker->xSelectCallback(pWalker, p);
+      /* Depth-first search is currently only used for
+      ** selectAddSubqueryTypeInfo() and that routine always returns
+      ** WRC_Continue (0).  So the following branch is never taken. */
+      if( NEVER(rc) ) break;
+    }
     p = p->pPrior;
   }
+  pWalker->walkerDepth--;
   return rc & WRC_Abort;
 }
 
@@ -74090,6 +74049,29 @@ SQLITE_PRIVATE int sqlite3WalkSelect(Walker *pWalker, Select *p){
 /* #include <stdlib.h> */
 /* #include <string.h> */
 
+/*
+** Walk the expression tree pExpr and increase the aggregate function
+** depth (the Expr.op2 field) by N on every TK_AGG_FUNCTION node.
+** This needs to occur when copying a TK_AGG_FUNCTION node from an
+** outer query into an inner subquery.
+**
+** incrAggFunctionDepth(pExpr,n) is the main routine.  incrAggDepth(..)
+** is a helper function - a callback for the tree walker.
+*/
+static int incrAggDepth(Walker *pWalker, Expr *pExpr){
+  if( pExpr->op==TK_AGG_FUNCTION ) pExpr->op2 += pWalker->u.i;
+  return WRC_Continue;
+}
+static void incrAggFunctionDepth(Expr *pExpr, int N){
+  if( N>0 ){
+    Walker w;
+    memset(&w, 0, sizeof(w));
+    w.xExprCallback = incrAggDepth;
+    w.u.i = N;
+    sqlite3WalkExpr(&w, pExpr);
+  }
+}
+
 /*
 ** Turn the pExpr expression into an alias for the iCol-th column of the
 ** result set in pEList.
@@ -74104,7 +74086,7 @@ SQLITE_PRIVATE int sqlite3WalkSelect(Walker *pWalker, Select *p){
 ** column reference is so that the column reference will be recognized as
 ** usable by indices within the WHERE clause processing logic. 
 **
-** Hack:  The TK_AS operator is inhibited if zType[0]=='G'.  This means
+** The TK_AS operator is inhibited if zType[0]=='G'.  This means
 ** that in a GROUP BY clause, the expression is evaluated twice.  Hence:
 **
 **     SELECT random()%5 AS x, count(*) FROM tab GROUP BY x
@@ -74114,15 +74096,32 @@ SQLITE_PRIVATE int sqlite3WalkSelect(Walker *pWalker, Select *p){
 **     SELECT random()%5 AS x, count(*) FROM tab GROUP BY random()%5
 **
 ** The result of random()%5 in the GROUP BY clause is probably different
-** from the result in the result-set.  We might fix this someday.  Or
-** then again, we might not...
+** from the result in the result-set.  On the other hand Standard SQL does
+** not allow the GROUP BY clause to contain references to result-set columns.
+** So this should never come up in well-formed queries.
+**
+** If the reference is followed by a COLLATE operator, then make sure
+** the COLLATE operator is preserved.  For example:
+**
+**     SELECT a+b, c+d FROM t1 ORDER BY 1 COLLATE nocase;
+**
+** Should be transformed into:
+**
+**     SELECT a+b, c+d FROM t1 ORDER BY (a+b) COLLATE nocase;
+**
+** The nSubquery parameter specifies how many levels of subquery the
+** alias is removed from the original expression.  The usually value is
+** zero but it might be more if the alias is contained within a subquery
+** of the original expression.  The Expr.op2 field of TK_AGG_FUNCTION
+** structures must be increased by the nSubquery amount.
 */
 static void resolveAlias(
   Parse *pParse,         /* Parsing context */
   ExprList *pEList,      /* A result set */
   int iCol,              /* A column in the result set.  0..pEList->nExpr-1 */
   Expr *pExpr,           /* Transform this into an alias to the result set */
-  const char *zType      /* "GROUP" or "ORDER" or "" */
+  const char *zType,     /* "GROUP" or "ORDER" or "" */
+  int nSubquery          /* Number of subqueries that the label is moving */
 ){
   Expr *pOrig;           /* The iCol-th column of the result set */
   Expr *pDup;            /* Copy of pOrig */
@@ -74133,40 +74132,36 @@ static void resolveAlias(
   assert( pOrig!=0 );
   assert( pOrig->flags & EP_Resolved );
   db = pParse->db;
+  pDup = sqlite3ExprDup(db, pOrig, 0);
+  if( pDup==0 ) return;
   if( pOrig->op!=TK_COLUMN && zType[0]!='G' ){
-    pDup = sqlite3ExprDup(db, pOrig, 0);
+    incrAggFunctionDepth(pDup, nSubquery);
     pDup = sqlite3PExpr(pParse, TK_AS, pDup, 0, 0);
     if( pDup==0 ) return;
     if( pEList->a[iCol].iAlias==0 ){
       pEList->a[iCol].iAlias = (u16)(++pParse->nAlias);
     }
     pDup->iTable = pEList->a[iCol].iAlias;
-  }else if( ExprHasProperty(pOrig, EP_IntValue) || pOrig->u.zToken==0 ){
-    pDup = sqlite3ExprDup(db, pOrig, 0);
-    if( pDup==0 ) return;
-  }else{
-    char *zToken = pOrig->u.zToken;
-    assert( zToken!=0 );
-    pOrig->u.zToken = 0;
-    pDup = sqlite3ExprDup(db, pOrig, 0);
-    pOrig->u.zToken = zToken;
-    if( pDup==0 ) return;
-    assert( (pDup->flags & (EP_Reduced|EP_TokenOnly))==0 );
-    pDup->flags2 |= EP2_MallocedToken;
-    pDup->u.zToken = sqlite3DbStrDup(db, zToken);
   }
-  if( pExpr->flags & EP_ExpCollate ){
-    pDup->pColl = pExpr->pColl;
-    pDup->flags |= EP_ExpCollate;
+  if( pExpr->op==TK_COLLATE ){
+    pDup = sqlite3ExprAddCollateString(pParse, pDup, pExpr->u.zToken);
   }
 
   /* Before calling sqlite3ExprDelete(), set the EP_Static flag. This 
   ** prevents ExprDelete() from deleting the Expr structure itself,
   ** allowing it to be repopulated by the memcpy() on the following line.
+  ** The pExpr->u.zToken might point into memory that will be freed by the
+  ** sqlite3DbFree(db, pDup) on the last line of this block, so be sure to
+  ** make a copy of the token before doing the sqlite3DbFree().
   */
   ExprSetProperty(pExpr, EP_Static);
   sqlite3ExprDelete(db, pExpr);
   memcpy(pExpr, pDup, sizeof(*pExpr));
+  if( !ExprHasProperty(pExpr, EP_IntValue) && pExpr->u.zToken!=0 ){
+    assert( (pExpr->flags & (EP_Reduced|EP_TokenOnly))==0 );
+    pExpr->u.zToken = sqlite3DbStrDup(db, pExpr->u.zToken);
+    pExpr->flags2 |= EP2_MallocedToken;
+  }
   sqlite3DbFree(db, pDup);
 }
 
@@ -74187,6 +74182,35 @@ static int nameInUsingClause(IdList *pUsing, const char *zCol){
   return 0;
 }
 
+/*
+** Subqueries stores the original database, table and column names for their
+** result sets in ExprList.a[].zSpan, in the form "DATABASE.TABLE.COLUMN".
+** Check to see if the zSpan given to this routine matches the zDb, zTab,
+** and zCol.  If any of zDb, zTab, and zCol are NULL then those fields will
+** match anything.
+*/
+SQLITE_PRIVATE int sqlite3MatchSpanName(
+  const char *zSpan,
+  const char *zCol,
+  const char *zTab,
+  const char *zDb
+){
+  int n;
+  for(n=0; ALWAYS(zSpan[n]) && zSpan[n]!='.'; n++){}
+  if( zDb && (sqlite3StrNICmp(zSpan, zDb, n)!=0 || zDb[n]!=0) ){
+    return 0;
+  }
+  zSpan += n+1;
+  for(n=0; ALWAYS(zSpan[n]) && zSpan[n]!='.'; n++){}
+  if( zTab && (sqlite3StrNICmp(zSpan, zTab, n)!=0 || zTab[n]!=0) ){
+    return 0;
+  }
+  zSpan += n+1;
+  if( zCol && sqlite3StrICmp(zSpan, zCol)!=0 ){
+    return 0;
+  }
+  return 1;
+}
 
 /*
 ** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up
@@ -74223,9 +74247,10 @@ static int lookupName(
   NameContext *pNC,    /* The name context used to resolve the name */
   Expr *pExpr          /* Make this EXPR node point to the selected column */
 ){
-  int i, j;            /* Loop counters */
+  int i, j;                         /* Loop counters */
   int cnt = 0;                      /* Number of matching column names */
   int cntTab = 0;                   /* Number of matching table names */
+  int nSubquery = 0;                /* How many levels of subquery */
   sqlite3 *db = pParse->db;         /* The database connection */
   struct SrcList_item *pItem;       /* Use for looping over pSrcList items */
   struct SrcList_item *pMatch = 0;  /* The matching pSrcList item */
@@ -74235,13 +74260,36 @@ static int lookupName(
 
   assert( pNC );     /* the name context cannot be NULL. */
   assert( zCol );    /* The Z in X.Y.Z cannot be NULL */
-  assert( ~ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );
+  assert( !ExprHasAnyProperty(pExpr, EP_TokenOnly|EP_Reduced) );
 
   /* Initialize the node to no-match */
   pExpr->iTable = -1;
   pExpr->pTab = 0;
   ExprSetIrreducible(pExpr);
 
+  /* Translate the schema name in zDb into a pointer to the corresponding
+  ** schema.  If not found, pSchema will remain NULL and nothing will match
+  ** resulting in an appropriate error message toward the end of this routine
+  */
+  if( zDb ){
+    testcase( pNC->ncFlags & NC_PartIdx );
+    testcase( pNC->ncFlags & NC_IsCheck );
+    if( (pNC->ncFlags & (NC_PartIdx|NC_IsCheck))!=0 ){
+      /* Silently ignore database qualifiers inside CHECK constraints and partial
+      ** indices.  Do not raise errors because that might break legacy and
+      ** because it does not hurt anything to just ignore the database name. */
+      zDb = 0;
+    }else{
+      for(i=0; i<db->nDb; i++){
+        assert( db->aDb[i].zName );
+        if( sqlite3StrICmp(db->aDb[i].zName,zDb)==0 ){
+          pSchema = db->aDb[i].pSchema;
+          break;
+        }
+      }
+    }
+  }
+
   /* Start at the inner-most context and move outward until a match is found */
   while( pNC && cnt==0 ){
     ExprList *pEList;
@@ -74250,31 +74298,36 @@ static int lookupName(
     if( pSrcList ){
       for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
         Table *pTab;
-        int iDb;
         Column *pCol;
   
         pTab = pItem->pTab;
         assert( pTab!=0 && pTab->zName!=0 );
-        iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
         assert( pTab->nCol>0 );
+        if( pItem->pSelect && (pItem->pSelect->selFlags & SF_NestedFrom)!=0 ){
+          int hit = 0;
+          pEList = pItem->pSelect->pEList;
+          for(j=0; j<pEList->nExpr; j++){
+            if( sqlite3MatchSpanName(pEList->a[j].zSpan, zCol, zTab, zDb) ){
+              cnt++;
+              cntTab = 2;
+              pMatch = pItem;
+              pExpr->iColumn = j;
+              hit = 1;
+            }
+          }
+          if( hit || zTab==0 ) continue;
+        }
+        if( zDb && pTab->pSchema!=pSchema ){
+          continue;
+        }
         if( zTab ){
-          if( pItem->zAlias ){
-            char *zTabName = pItem->zAlias;
-            if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
-          }else{
-            char *zTabName = pTab->zName;
-            if( NEVER(zTabName==0) || sqlite3StrICmp(zTabName, zTab)!=0 ){
-              continue;
-            }
-            if( zDb!=0 && sqlite3StrICmp(db->aDb[iDb].zName, zDb)!=0 ){
-              continue;
-            }
+          const char *zTabName = pItem->zAlias ? pItem->zAlias : pTab->zName;
+          assert( zTabName!=0 );
+          if( sqlite3StrICmp(zTabName, zTab)!=0 ){
+            continue;
           }
         }
         if( 0==(cntTab++) ){
-          pExpr->iTable = pItem->iCursor;
-          pExpr->pTab = pTab;
-          pSchema = pTab->pSchema;
           pMatch = pItem;
         }
         for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
@@ -74288,17 +74341,19 @@ static int lookupName(
               if( nameInUsingClause(pItem->pUsing, zCol) ) continue;
             }
             cnt++;
-            pExpr->iTable = pItem->iCursor;
-            pExpr->pTab = pTab;
             pMatch = pItem;
-            pSchema = pTab->pSchema;
             /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
             pExpr->iColumn = j==pTab->iPKey ? -1 : (i16)j;
             break;
           }
         }
       }
-    }
+      if( pMatch ){
+        pExpr->iTable = pMatch->iCursor;
+        pExpr->pTab = pMatch->pTab;
+        pSchema = pExpr->pTab->pSchema;
+      }
+    } /* if( pSrcList ) */
 
 #ifndef SQLITE_OMIT_TRIGGER
     /* If we have not already resolved the name, then maybe 
@@ -74373,8 +74428,17 @@ static int lookupName(
     ** forms the result set entry ("a+b" in the example) and return immediately.
     ** Note that the expression in the result set should have already been
     ** resolved by the time the WHERE clause is resolved.
+    **
+    ** The ability to use an output result-set column in the WHERE, GROUP BY,
+    ** or HAVING clauses, or as part of a larger expression in the ORDRE BY
+    ** clause is not standard SQL.  This is a (goofy) SQLite extension, that
+    ** is supported for backwards compatibility only.  TO DO: Issue a warning
+    ** on sqlite3_log() whenever the capability is used.
     */
-    if( cnt==0 && (pEList = pNC->pEList)!=0 && zTab==0 ){
+    if( (pEList = pNC->pEList)!=0
+     && zTab==0
+     && cnt==0
+    ){
       for(j=0; j<pEList->nExpr; j++){
         char *zAs = pEList->a[j].zName;
         if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){
@@ -74387,7 +74451,7 @@ static int lookupName(
             sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
             return WRC_Abort;
           }
-          resolveAlias(pParse, pEList, j, pExpr, "");
+          resolveAlias(pParse, pEList, j, pExpr, "", nSubquery);
           cnt = 1;
           pMatch = 0;
           assert( zTab==0 && zDb==0 );
@@ -74401,6 +74465,7 @@ static int lookupName(
     */
     if( cnt==0 ){
       pNC = pNC->pNext;
+      nSubquery++;
     }
   }
 
@@ -74464,7 +74529,9 @@ static int lookupName(
 lookupname_end:
   if( cnt==1 ){
     assert( pNC!=0 );
-    sqlite3AuthRead(pParse, pExpr, pSchema, pNC->pSrcList);
+    if( pExpr->op!=TK_AS ){
+      sqlite3AuthRead(pParse, pExpr, pSchema, pNC->pSrcList);
+    }
     /* Increment the nRef value on all name contexts from TopNC up to
     ** the point where the name matched. */
     for(;;){
@@ -74502,6 +74569,39 @@ SQLITE_PRIVATE Expr *sqlite3CreateColumnExpr(sqlite3 *db, SrcList *pSrc, int iSr
   return p;
 }
 
+/*
+** Report an error that an expression is not valid for a partial index WHERE
+** clause.
+*/
+static void notValidPartIdxWhere(
+  Parse *pParse,       /* Leave error message here */
+  NameContext *pNC,    /* The name context */
+  const char *zMsg     /* Type of error */
+){
+  if( (pNC->ncFlags & NC_PartIdx)!=0 ){
+    sqlite3ErrorMsg(pParse, "%s prohibited in partial index WHERE clauses",
+                    zMsg);
+  }
+}
+
+#ifndef SQLITE_OMIT_CHECK
+/*
+** Report an error that an expression is not valid for a CHECK constraint.
+*/
+static void notValidCheckConstraint(
+  Parse *pParse,       /* Leave error message here */
+  NameContext *pNC,    /* The name context */
+  const char *zMsg     /* Type of error */
+){
+  if( (pNC->ncFlags & NC_IsCheck)!=0 ){
+    sqlite3ErrorMsg(pParse,"%s prohibited in CHECK constraints", zMsg);
+  }
+}
+#else
+# define notValidCheckConstraint(P,N,M)
+#endif
+
+
 /*
 ** This routine is callback for sqlite3WalkExpr().
 **
@@ -74601,6 +74701,7 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
 
       testcase( pExpr->op==TK_CONST_FUNC );
       assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
+      notValidPartIdxWhere(pParse, pNC, "functions");
       zId = pExpr->u.zToken;
       nId = sqlite3Strlen30(zId);
       pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0);
@@ -74632,7 +74733,7 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
         sqlite3ErrorMsg(pParse, "misuse of aggregate function %.*s()", nId,zId);
         pNC->nErr++;
         is_agg = 0;
-      }else if( no_such_func ){
+      }else if( no_such_func && pParse->db->init.busy==0 ){
         sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId);
         pNC->nErr++;
       }else if( wrong_num_args ){
@@ -74640,13 +74741,19 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
              nId, zId);
         pNC->nErr++;
       }
-      if( is_agg ){
-        pExpr->op = TK_AGG_FUNCTION;
-        pNC->ncFlags |= NC_HasAgg;
-      }
       if( is_agg ) pNC->ncFlags &= ~NC_AllowAgg;
       sqlite3WalkExprList(pWalker, pList);
-      if( is_agg ) pNC->ncFlags |= NC_AllowAgg;
+      if( is_agg ){
+        NameContext *pNC2 = pNC;
+        pExpr->op = TK_AGG_FUNCTION;
+        pExpr->op2 = 0;
+        while( pNC2 && !sqlite3FunctionUsesThisSrc(pExpr, pNC2->pSrcList) ){
+          pExpr->op2++;
+          pNC2 = pNC2->pNext;
+        }
+        if( pNC2 ) pNC2->ncFlags |= NC_HasAgg;
+        pNC->ncFlags |= NC_AllowAgg;
+      }
       /* FIX ME:  Compute pExpr->affinity based on the expected return
       ** type of the function 
       */
@@ -74660,11 +74767,8 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
       testcase( pExpr->op==TK_IN );
       if( ExprHasProperty(pExpr, EP_xIsSelect) ){
         int nRef = pNC->nRef;
-#ifndef SQLITE_OMIT_CHECK
-        if( (pNC->ncFlags & NC_IsCheck)!=0 ){
-          sqlite3ErrorMsg(pParse,"subqueries prohibited in CHECK constraints");
-        }
-#endif
+        notValidCheckConstraint(pParse, pNC, "subqueries");
+        notValidPartIdxWhere(pParse, pNC, "subqueries");
         sqlite3WalkSelect(pWalker, pExpr->x.pSelect);
         assert( pNC->nRef>=nRef );
         if( nRef!=pNC->nRef ){
@@ -74673,14 +74777,11 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
       }
       break;
     }
-#ifndef SQLITE_OMIT_CHECK
     case TK_VARIABLE: {
-      if( (pNC->ncFlags & NC_IsCheck)!=0 ){
-        sqlite3ErrorMsg(pParse,"parameters prohibited in CHECK constraints");
-      }
+      notValidCheckConstraint(pParse, pNC, "parameters");
+      notValidPartIdxWhere(pParse, pNC, "parameters");
       break;
     }
-#endif
   }
   return (pParse->nErr || pParse->db->mallocFailed) ? WRC_Abort : WRC_Continue;
 }
@@ -74771,7 +74872,7 @@ static int resolveOrderByTermToExprList(
   ** result-set entry.
   */
   for(i=0; i<pEList->nExpr; i++){
-    if( sqlite3ExprCompare(pEList->a[i].pExpr, pE)<2 ){
+    if( sqlite3ExprCompare(pEList->a[i].pExpr, pE, -1)<2 ){
       return i+1;
     }
   }
@@ -74845,7 +74946,7 @@ static int resolveCompoundOrderBy(
       int iCol = -1;
       Expr *pE, *pDup;
       if( pItem->done ) continue;
-      pE = pItem->pExpr;
+      pE = sqlite3ExprSkipCollate(pItem->pExpr);
       if( sqlite3ExprIsInteger(pE, &iCol) ){
         if( iCol<=0 || iCol>pEList->nExpr ){
           resolveOutOfRangeError(pParse, "ORDER", i+1, pEList->nExpr);
@@ -74863,14 +74964,20 @@ static int resolveCompoundOrderBy(
         }
       }
       if( iCol>0 ){
-        CollSeq *pColl = pE->pColl;
-        int flags = pE->flags & EP_ExpCollate;
+        /* Convert the ORDER BY term into an integer column number iCol,
+        ** taking care to preserve the COLLATE clause if it exists */
+        Expr *pNew = sqlite3Expr(db, TK_INTEGER, 0);
+        if( pNew==0 ) return 1;
+        pNew->flags |= EP_IntValue;
+        pNew->u.iValue = iCol;
+        if( pItem->pExpr==pE ){
+          pItem->pExpr = pNew;
+        }else{
+          assert( pItem->pExpr->op==TK_COLLATE );
+          assert( pItem->pExpr->pLeft==pE );
+          pItem->pExpr->pLeft = pNew;
+        }
         sqlite3ExprDelete(db, pE);
-        pItem->pExpr = pE = sqlite3Expr(db, TK_INTEGER, 0);
-        if( pE==0 ) return 1;
-        pE->pColl = pColl;
-        pE->flags |= EP_IntValue | flags;
-        pE->u.iValue = iCol;
         pItem->iOrderByCol = (u16)iCol;
         pItem->done = 1;
       }else{
@@ -74892,7 +74999,7 @@ static int resolveCompoundOrderBy(
 /*
 ** Check every term in the ORDER BY or GROUP BY clause pOrderBy of
 ** the SELECT statement pSelect.  If any term is reference to a
-** result set expression (as determined by the ExprList.a.iCol field)
+** result set expression (as determined by the ExprList.a.iOrderByCol field)
 ** then convert that term into a copy of the corresponding result set
 ** column.
 **
@@ -74925,7 +75032,7 @@ SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(
         resolveOutOfRangeError(pParse, zType, i+1, pEList->nExpr);
         return 1;
       }
-      resolveAlias(pParse, pEList, pItem->iOrderByCol-1, pItem->pExpr, zType);
+      resolveAlias(pParse, pEList, pItem->iOrderByCol-1, pItem->pExpr, zType,0);
     }
   }
   return 0;
@@ -74940,7 +75047,7 @@ SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(
 ** If the order-by term is an integer I between 1 and N (where N is the
 ** number of columns in the result set of the SELECT) then the expression
 ** in the resolution is a copy of the I-th result-set expression.  If
-** the order-by term is an identify that corresponds to the AS-name of
+** the order-by term is an identifier that corresponds to the AS-name of
 ** a result-set expression, then the term resolves to a copy of the
 ** result-set expression.  Otherwise, the expression is resolved in
 ** the usual way - using sqlite3ResolveExprNames().
@@ -74966,20 +75073,23 @@ static int resolveOrderGroupBy(
   pParse = pNC->pParse;
   for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){
     Expr *pE = pItem->pExpr;
-    iCol = resolveAsName(pParse, pSelect->pEList, pE);
-    if( iCol>0 ){
-      /* If an AS-name match is found, mark this ORDER BY column as being
-      ** a copy of the iCol-th result-set column.  The subsequent call to
-      ** sqlite3ResolveOrderGroupBy() will convert the expression to a
-      ** copy of the iCol-th result-set expression. */
-      pItem->iOrderByCol = (u16)iCol;
-      continue;
+    Expr *pE2 = sqlite3ExprSkipCollate(pE);
+    if( zType[0]!='G' ){
+      iCol = resolveAsName(pParse, pSelect->pEList, pE2);
+      if( iCol>0 ){
+        /* If an AS-name match is found, mark this ORDER BY column as being
+        ** a copy of the iCol-th result-set column.  The subsequent call to
+        ** sqlite3ResolveOrderGroupBy() will convert the expression to a
+        ** copy of the iCol-th result-set expression. */
+        pItem->iOrderByCol = (u16)iCol;
+        continue;
+      }
     }
-    if( sqlite3ExprIsInteger(pE, &iCol) ){
+    if( sqlite3ExprIsInteger(pE2, &iCol) ){
       /* The ORDER BY term is an integer constant.  Again, set the column
       ** number so that sqlite3ResolveOrderGroupBy() will convert the
       ** order-by term to a copy of the result-set expression */
-      if( iCol<1 ){
+      if( iCol<1 || iCol>0xffff ){
         resolveOutOfRangeError(pParse, zType, i+1, nResult);
         return 1;
       }
@@ -74993,7 +75103,7 @@ static int resolveOrderGroupBy(
       return 1;
     }
     for(j=0; j<pSelect->pEList->nExpr; j++){
-      if( sqlite3ExprCompare(pE, pSelect->pEList->a[j].pExpr)==0 ){
+      if( sqlite3ExprCompare(pE, pSelect->pEList->a[j].pExpr, -1)==0 ){
         pItem->iOrderByCol = j+1;
       }
     }
@@ -75056,23 +75166,6 @@ static int resolveSelectStep(Walker *pWalker, Select *p){
       return WRC_Abort;
     }
   
-    /* Set up the local name-context to pass to sqlite3ResolveExprNames() to
-    ** resolve the result-set expression list.
-    */
-    sNC.ncFlags = NC_AllowAgg;
-    sNC.pSrcList = p->pSrc;
-    sNC.pNext = pOuterNC;
-  
-    /* Resolve names in the result set. */
-    pEList = p->pEList;
-    assert( pEList!=0 );
-    for(i=0; i<pEList->nExpr; i++){
-      Expr *pX = pEList->a[i].pExpr;
-      if( sqlite3ResolveExprNames(&sNC, pX) ){
-        return WRC_Abort;
-      }
-    }
-  
     /* Recursively resolve names in all subqueries
     */
     for(i=0; i<p->pSrc->nSrc; i++){
@@ -75100,6 +75193,23 @@ static int resolveSelectStep(Walker *pWalker, Select *p){
       }
     }
   
+    /* Set up the local name-context to pass to sqlite3ResolveExprNames() to
+    ** resolve the result-set expression list.
+    */
+    sNC.ncFlags = NC_AllowAgg;
+    sNC.pSrcList = p->pSrc;
+    sNC.pNext = pOuterNC;
+  
+    /* Resolve names in the result set. */
+    pEList = p->pEList;
+    assert( pEList!=0 );
+    for(i=0; i<pEList->nExpr; i++){
+      Expr *pX = pEList->a[i].pExpr;
+      if( sqlite3ResolveExprNames(&sNC, pX) ){
+        return WRC_Abort;
+      }
+    }
+  
     /* If there are no aggregate functions in the result-set, and no GROUP BY 
     ** expression, do not allow aggregates in any of the other expressions.
     */
@@ -75118,7 +75228,7 @@ static int resolveSelectStep(Walker *pWalker, Select *p){
       return WRC_Abort;
     }
   
-    /* Add the expression list to the name-context before parsing the
+    /* Add the output column list to the name-context before parsing the
     ** other expressions in the SELECT statement. This is so that
     ** expressions in the WHERE clause (etc.) can refer to expressions by
     ** aliases in the result set.
@@ -75127,11 +75237,8 @@ static int resolveSelectStep(Walker *pWalker, Select *p){
     ** re-evaluated for each reference to it.
     */
     sNC.pEList = p->pEList;
-    if( sqlite3ResolveExprNames(&sNC, p->pWhere) ||
-       sqlite3ResolveExprNames(&sNC, p->pHaving)
-    ){
-      return WRC_Abort;
-    }
+    if( sqlite3ResolveExprNames(&sNC, p->pHaving) ) return WRC_Abort;
+    if( sqlite3ResolveExprNames(&sNC, p->pWhere) ) return WRC_Abort;
 
     /* The ORDER BY and GROUP BY clauses may not refer to terms in
     ** outer queries 
@@ -75252,6 +75359,7 @@ SQLITE_PRIVATE int sqlite3ResolveExprNames(
 #endif
   savedHasAgg = pNC->ncFlags & NC_HasAgg;
   pNC->ncFlags &= ~NC_HasAgg;
+  memset(&w, 0, sizeof(w));
   w.xExprCallback = resolveExprStep;
   w.xSelectCallback = resolveSelectStep;
   w.pParse = pNC->pParse;
@@ -75292,6 +75400,7 @@ SQLITE_PRIVATE void sqlite3ResolveSelectNames(
   Walker w;
 
   assert( p!=0 );
+  memset(&w, 0, sizeof(w));
   w.xExprCallback = resolveExprStep;
   w.xSelectCallback = resolveSelectStep;
   w.pParse = pParse;
@@ -75299,6 +75408,48 @@ SQLITE_PRIVATE void sqlite3ResolveSelectNames(
   sqlite3WalkSelect(&w, p);
 }
 
+/*
+** Resolve names in expressions that can only reference a single table:
+**
+**    *   CHECK constraints
+**    *   WHERE clauses on partial indices
+**
+** The Expr.iTable value for Expr.op==TK_COLUMN nodes of the expression
+** is set to -1 and the Expr.iColumn value is set to the column number.
+**
+** Any errors cause an error message to be set in pParse.
+*/
+SQLITE_PRIVATE void sqlite3ResolveSelfReference(
+  Parse *pParse,      /* Parsing context */
+  Table *pTab,        /* The table being referenced */
+  int type,           /* NC_IsCheck or NC_PartIdx */
+  Expr *pExpr,        /* Expression to resolve.  May be NULL. */
+  ExprList *pList     /* Expression list to resolve.  May be NUL. */
+){
+  SrcList sSrc;                   /* Fake SrcList for pParse->pNewTable */
+  NameContext sNC;                /* Name context for pParse->pNewTable */
+  int i;                          /* Loop counter */
+
+  assert( type==NC_IsCheck || type==NC_PartIdx );
+  memset(&sNC, 0, sizeof(sNC));
+  memset(&sSrc, 0, sizeof(sSrc));
+  sSrc.nSrc = 1;
+  sSrc.a[0].zName = pTab->zName;
+  sSrc.a[0].pTab = pTab;
+  sSrc.a[0].iCursor = -1;
+  sNC.pParse = pParse;
+  sNC.pSrcList = &sSrc;
+  sNC.ncFlags = type;
+  if( sqlite3ResolveExprNames(&sNC, pExpr) ) return;
+  if( pList ){
+    for(i=0; i<pList->nExpr; i++){
+      if( sqlite3ResolveExprNames(&sNC, pList->a[i].pExpr) ){
+        return;
+      }
+    }
+  }
+}
+
 /************** End of resolve.c *********************************************/
 /************** Begin file expr.c ********************************************/
 /*
@@ -75333,7 +75484,9 @@ SQLITE_PRIVATE void sqlite3ResolveSelectNames(
 ** SELECT * FROM t1 WHERE (select a from t1);
 */
 SQLITE_PRIVATE char sqlite3ExprAffinity(Expr *pExpr){
-  int op = pExpr->op;
+  int op;
+  pExpr = sqlite3ExprSkipCollate(pExpr);
+  op = pExpr->op;
   if( op==TK_SELECT ){
     assert( pExpr->flags&EP_xIsSelect );
     return sqlite3ExprAffinity(pExpr->x.pSelect->pEList->a[0].pExpr);
@@ -75358,66 +75511,88 @@ SQLITE_PRIVATE char sqlite3ExprAffinity(Expr *pExpr){
 }
 
 /*
-** Set the explicit collating sequence for an expression to the
-** collating sequence supplied in the second argument.
+** Set the collating sequence for expression pExpr to be the collating
+** sequence named by pToken.   Return a pointer to a new Expr node that
+** implements the COLLATE operator.
+**
+** If a memory allocation error occurs, that fact is recorded in pParse->db
+** and the pExpr parameter is returned unchanged.
 */
-SQLITE_PRIVATE Expr *sqlite3ExprSetColl(Expr *pExpr, CollSeq *pColl){
-  if( pExpr && pColl ){
-    pExpr->pColl = pColl;
-    pExpr->flags |= EP_ExpCollate;
+SQLITE_PRIVATE Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr *pExpr, Token *pCollName){
+  if( pCollName->n>0 ){
+    Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLLATE, pCollName, 1);
+    if( pNew ){
+      pNew->pLeft = pExpr;
+      pNew->flags |= EP_Collate;
+      pExpr = pNew;
+    }
+  }
+  return pExpr;
+}
+SQLITE_PRIVATE Expr *sqlite3ExprAddCollateString(Parse *pParse, Expr *pExpr, const char *zC){
+  Token s;
+  assert( zC!=0 );
+  s.z = zC;
+  s.n = sqlite3Strlen30(s.z);
+  return sqlite3ExprAddCollateToken(pParse, pExpr, &s);
+}
+
+/*
+** Skip over any TK_COLLATE and/or TK_AS operators at the root of
+** an expression.
+*/
+SQLITE_PRIVATE Expr *sqlite3ExprSkipCollate(Expr *pExpr){
+  while( pExpr && (pExpr->op==TK_COLLATE || pExpr->op==TK_AS) ){
+    pExpr = pExpr->pLeft;
   }
   return pExpr;
 }
 
 /*
-** Set the collating sequence for expression pExpr to be the collating
-** sequence named by pToken.   Return a pointer to the revised expression.
-** The collating sequence is marked as "explicit" using the EP_ExpCollate
-** flag.  An explicit collating sequence will override implicit
-** collating sequences.
-*/
-SQLITE_PRIVATE Expr *sqlite3ExprSetCollByToken(Parse *pParse, Expr *pExpr, Token *pCollName){
-  char *zColl = 0;            /* Dequoted name of collation sequence */
-  CollSeq *pColl;
-  sqlite3 *db = pParse->db;
-  zColl = sqlite3NameFromToken(db, pCollName);
-  pColl = sqlite3LocateCollSeq(pParse, zColl);
-  sqlite3ExprSetColl(pExpr, pColl);
-  sqlite3DbFree(db, zColl);
-  return pExpr;
-}
-
-/*
-** Return the default collation sequence for the expression pExpr. If
-** there is no default collation type, return 0.
+** Return the collation sequence for the expression pExpr. If
+** there is no defined collating sequence, return NULL.
+**
+** The collating sequence might be determined by a COLLATE operator
+** or by the presence of a column with a defined collating sequence.
+** COLLATE operators take first precedence.  Left operands take
+** precedence over right operands.
 */
 SQLITE_PRIVATE CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){
+  sqlite3 *db = pParse->db;
   CollSeq *pColl = 0;
   Expr *p = pExpr;
   while( p ){
-    int op;
-    pColl = p->pColl;
-    if( pColl ) break;
-    op = p->op;
-    if( p->pTab!=0 && (
-        op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_REGISTER || op==TK_TRIGGER
-    )){
+    int op = p->op;
+    if( op==TK_CAST || op==TK_UPLUS ){
+      p = p->pLeft;
+      continue;
+    }
+    if( op==TK_COLLATE || (op==TK_REGISTER && p->op2==TK_COLLATE) ){
+      pColl = sqlite3GetCollSeq(pParse, ENC(db), 0, p->u.zToken);
+      break;
+    }
+    if( p->pTab!=0
+     && (op==TK_AGG_COLUMN || op==TK_COLUMN
+          || op==TK_REGISTER || op==TK_TRIGGER)
+    ){
       /* op==TK_REGISTER && p->pTab!=0 happens when pExpr was originally
       ** a TK_COLUMN but was previously evaluated and cached in a register */
-      const char *zColl;
       int j = p->iColumn;
       if( j>=0 ){
-        sqlite3 *db = pParse->db;
-        zColl = p->pTab->aCol[j].zColl;
+        const char *zColl = p->pTab->aCol[j].zColl;
         pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0);
-        pExpr->pColl = pColl;
       }
       break;
     }
-    if( op!=TK_CAST && op!=TK_UPLUS ){
+    if( p->flags & EP_Collate ){
+      if( ALWAYS(p->pLeft) && (p->pLeft->flags & EP_Collate)!=0 ){
+        p = p->pLeft;
+      }else{
+        p = p->pRight;
+      }
+    }else{
       break;
     }
-    p = p->pLeft;
   }
   if( sqlite3CheckCollSeq(pParse, pColl) ){ 
     pColl = 0;
@@ -75521,12 +75696,10 @@ SQLITE_PRIVATE CollSeq *sqlite3BinaryCompareCollSeq(
 ){
   CollSeq *pColl;
   assert( pLeft );
-  if( pLeft->flags & EP_ExpCollate ){
-    assert( pLeft->pColl );
-    pColl = pLeft->pColl;
-  }else if( pRight && pRight->flags & EP_ExpCollate ){
-    assert( pRight->pColl );
-    pColl = pRight->pColl;
+  if( pLeft->flags & EP_Collate ){
+    pColl = sqlite3ExprCollSeq(pParse, pLeft);
+  }else if( pRight && (pRight->flags & EP_Collate)!=0 ){
+    pColl = sqlite3ExprCollSeq(pParse, pRight);
   }else{
     pColl = sqlite3ExprCollSeq(pParse, pLeft);
     if( !pColl ){
@@ -75756,17 +75929,11 @@ SQLITE_PRIVATE void sqlite3ExprAttachSubtrees(
   }else{
     if( pRight ){
       pRoot->pRight = pRight;
-      if( pRight->flags & EP_ExpCollate ){
-        pRoot->flags |= EP_ExpCollate;
-        pRoot->pColl = pRight->pColl;
-      }
+      pRoot->flags |= EP_Collate & pRight->flags;
     }
     if( pLeft ){
       pRoot->pLeft = pLeft;
-      if( pLeft->flags & EP_ExpCollate ){
-        pRoot->flags |= EP_ExpCollate;
-        pRoot->pColl = pLeft->pColl;
-      }
+      pRoot->flags |= EP_Collate & pLeft->flags;
     }
     exprSetHeight(pRoot);
   }
@@ -75918,7 +76085,7 @@ SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){
       */
       ynVar i;
       for(i=0; i<pParse->nzVar; i++){
-        if( pParse->azVar[i] && memcmp(pParse->azVar[i],z,n+1)==0 ){
+        if( pParse->azVar[i] && strcmp(pParse->azVar[i],z)==0 ){
           pExpr->iColumn = x = (ynVar)i+1;
           break;
         }
@@ -76024,7 +76191,7 @@ static int dupedExprStructSize(Expr *p, int flags){
     assert( !ExprHasProperty(p, EP_FromJoin) ); 
     assert( (p->flags2 & EP2_MallocedToken)==0 );
     assert( (p->flags2 & EP2_Irreducible)==0 );
-    if( p->pLeft || p->pRight || p->pColl || p->x.pList ){
+    if( p->pLeft || p->pRight || p->x.pList ){
       nSize = EXPR_REDUCEDSIZE | EP_Reduced;
     }else{
       nSize = EXPR_TOKENONLYSIZE | EP_TokenOnly;
@@ -76205,6 +76372,7 @@ SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p, int flags)
     pItem->zSpan = sqlite3DbStrDup(db, pOldItem->zSpan);
     pItem->sortOrder = pOldItem->sortOrder;
     pItem->done = 0;
+    pItem->bSpanIsTab = pOldItem->bSpanIsTab;
     pItem->iOrderByCol = pOldItem->iOrderByCol;
     pItem->iAlias = pOldItem->iAlias;
   }
@@ -76232,6 +76400,7 @@ SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p, int flags){
     struct SrcList_item *pNewItem = &pNew->a[i];
     struct SrcList_item *pOldItem = &p->a[i];
     Table *pTab;
+    pNewItem->pSchema = pOldItem->pSchema;
     pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
     pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
     pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
@@ -76240,6 +76409,7 @@ SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p, int flags){
     pNewItem->addrFillSub = pOldItem->addrFillSub;
     pNewItem->regReturn = pOldItem->regReturn;
     pNewItem->isCorrelated = pOldItem->isCorrelated;
+    pNewItem->viaCoroutine = pOldItem->viaCoroutine;
     pNewItem->zIndex = sqlite3DbStrDup(db, pOldItem->zIndex);
     pNewItem->notIndexed = pOldItem->notIndexed;
     pNewItem->pIndex = pOldItem->pIndex;
@@ -76492,6 +76662,7 @@ static int selectNodeIsConstant(Walker *pWalker, Select *NotUsed){
 }
 static int exprIsConst(Expr *p, int initFlag){
   Walker w;
+  memset(&w, 0, sizeof(w));
   w.u.i = initFlag;
   w.xExprCallback = exprNodeIsConstant;
   w.xSelectCallback = selectNodeIsConstant;
@@ -76560,6 +76731,7 @@ SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr *p, int *pValue){
     case TK_UMINUS: {
       int v;
       if( sqlite3ExprIsInteger(p->pLeft, &v) ){
+        assert( v!=-2147483648 );
         *pValue = -v;
         rc = 1;
       }
@@ -76722,24 +76894,34 @@ SQLITE_PRIVATE int sqlite3CodeOnce(Parse *pParse){
 
 /*
 ** This function is used by the implementation of the IN (...) operator.
-** It's job is to find or create a b-tree structure that may be used
-** either to test for membership of the (...) set or to iterate through
-** its members, skipping duplicates.
+** The pX parameter is the expression on the RHS of the IN operator, which
+** might be either a list of expressions or a subquery.
+**
+** The job of this routine is to find or create a b-tree object that can
+** be used either to test for membership in the RHS set or to iterate through
+** all members of the RHS set, skipping duplicates.
+**
+** A cursor is opened on the b-tree object that the RHS of the IN operator
+** and pX->iTable is set to the index of that cursor.
 **
-** The index of the cursor opened on the b-tree (database table, database index 
-** or ephermal table) is stored in pX->iTable before this function returns.
 ** The returned value of this function indicates the b-tree type, as follows:
 **
-**   IN_INDEX_ROWID - The cursor was opened on a database table.
-**   IN_INDEX_INDEX - The cursor was opened on a database index.
-**   IN_INDEX_EPH -   The cursor was opened on a specially created and
-**                    populated epheremal table.
+**   IN_INDEX_ROWID      - The cursor was opened on a database table.
+**   IN_INDEX_INDEX_ASC  - The cursor was opened on an ascending index.
+**   IN_INDEX_INDEX_DESC - The cursor was opened on a descending index.
+**   IN_INDEX_EPH        - The cursor was opened on a specially created and
+**                         populated epheremal table.
 **
-** An existing b-tree may only be used if the SELECT is of the simple
-** form:
+** An existing b-tree might be used if the RHS expression pX is a simple
+** subquery such as:
 **
 **     SELECT <column> FROM <table>
 **
+** If the RHS of the IN operator is a list or a more complex subquery, then
+** an ephemeral table might need to be generated from the RHS and then
+** pX->iTable made to point to the ephermeral table instead of an
+** existing table.  
+**
 ** If the prNotFound parameter is 0, then the b-tree will be used to iterate
 ** through the set members, skipping any duplicates. In this case an
 ** epheremal table must be used unless the selected <column> is guaranteed
@@ -76835,8 +77017,7 @@ SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
       ** comparison is the same as the affinity of the column. If
       ** it is not, it is not possible to use any index.
       */
-      char aff = comparisonAffinity(pX);
-      int affinity_ok = (pTab->aCol[iCol].affinity==aff||aff==SQLITE_AFF_NONE);
+      int affinity_ok = sqlite3IndexAffinityOk(pX, pTab->aCol[iCol].affinity);
 
       for(pIdx=pTab->pIndex; pIdx && eType==0 && affinity_ok; pIdx=pIdx->pNext){
         if( (pIdx->aiColumn[0]==iCol)
@@ -76852,7 +77033,8 @@ SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
           sqlite3VdbeAddOp4(v, OP_OpenRead, iTab, pIdx->tnum, iDb,
                                pKey,P4_KEYINFO_HANDOFF);
           VdbeComment((v, "%s", pIdx->zName));
-          eType = IN_INDEX_INDEX;
+          assert( IN_INDEX_INDEX_DESC == IN_INDEX_INDEX_ASC+1 );
+          eType = IN_INDEX_INDEX_ASC + pIdx->aSortOrder[0];
 
           sqlite3VdbeJumpHere(v, iAddr);
           if( prNotFound && !pTab->aCol[iCol].notNull ){
@@ -76868,15 +77050,15 @@ SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
     /* Could not found an existing table or index to use as the RHS b-tree.
     ** We will have to generate an ephemeral table to do the job.
     */
-    double savedNQueryLoop = pParse->nQueryLoop;
+    u32 savedNQueryLoop = pParse->nQueryLoop;
     int rMayHaveNull = 0;
     eType = IN_INDEX_EPH;
     if( prNotFound ){
       *prNotFound = rMayHaveNull = ++pParse->nMem;
       sqlite3VdbeAddOp2(v, OP_Null, 0, *prNotFound);
     }else{
-      testcase( pParse->nQueryLoop>(double)1 );
-      pParse->nQueryLoop = (double)1;
+      testcase( pParse->nQueryLoop>0 );
+      pParse->nQueryLoop = 0;
       if( pX->pLeft->iColumn<0 && !ExprHasAnyProperty(pX, EP_xIsSelect) ){
         eType = IN_INDEX_ROWID;
       }
@@ -76918,7 +77100,7 @@ SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
 **
 ** If rMayHaveNull is zero, that means that the subquery is being used
 ** for membership testing only.  There is no need to initialize any
-** registers to indicate the presense or absence of NULLs on the RHS.
+** registers to indicate the presence or absence of NULLs on the RHS.
 **
 ** For a SELECT or EXISTS operator, return the register that holds the
 ** result.  For IN operators or if an error occurs, the return value is 0.
@@ -76963,9 +77145,9 @@ SQLITE_PRIVATE int sqlite3CodeSubselect(
   switch( pExpr->op ){
     case TK_IN: {
       char affinity;              /* Affinity of the LHS of the IN */
-      KeyInfo keyInfo;            /* Keyinfo for the generated table */
       int addr;                   /* Address of OP_OpenEphemeral instruction */
       Expr *pLeft = pExpr->pLeft; /* the LHS of the IN operator */
+      KeyInfo *pKeyInfo = 0;      /* Key information */
 
       if( rMayHaveNull ){
         sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
@@ -76989,8 +77171,7 @@ SQLITE_PRIVATE int sqlite3CodeSubselect(
       pExpr->iTable = pParse->nTab++;
       addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, !isRowid);
       if( rMayHaveNull==0 ) sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
-      memset(&keyInfo, 0, sizeof(keyInfo));
-      keyInfo.nField = 1;
+      pKeyInfo = isRowid ? 0 : sqlite3KeyInfoAlloc(pParse->db, 1);
 
       if( ExprHasProperty(pExpr, EP_xIsSelect) ){
         /* Case 1:     expr IN (SELECT ...)
@@ -77003,17 +77184,20 @@ SQLITE_PRIVATE int sqlite3CodeSubselect(
 
         assert( !isRowid );
         sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
-        dest.affinity = (u8)affinity;
+        dest.affSdst = (u8)affinity;
         assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
         pExpr->x.pSelect->iLimit = 0;
+        testcase( pKeyInfo==0 ); /* Caused by OOM in sqlite3KeyInfoAlloc() */
         if( sqlite3Select(pParse, pExpr->x.pSelect, &dest) ){
+          sqlite3DbFree(pParse->db, pKeyInfo);
           return 0;
         }
         pEList = pExpr->x.pSelect->pEList;
-        if( ALWAYS(pEList!=0 && pEList->nExpr>0) ){ 
-          keyInfo.aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
-              pEList->a[0].pExpr);
-        }
+        assert( pKeyInfo!=0 ); /* OOM will cause exit after sqlite3Select() */
+        assert( pEList!=0 );
+        assert( pEList->nExpr>0 );
+        pKeyInfo->aColl[0] = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft,
+                                                         pEList->a[0].pExpr);
       }else if( ALWAYS(pExpr->x.pList!=0) ){
         /* Case 2:     expr IN (exprlist)
         **
@@ -77030,7 +77214,9 @@ SQLITE_PRIVATE int sqlite3CodeSubselect(
         if( !affinity ){
           affinity = SQLITE_AFF_NONE;
         }
-        keyInfo.aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
+        if( pKeyInfo ){
+          pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
+        }
 
         /* Loop through each expression in <exprlist>. */
         r1 = sqlite3GetTempReg(pParse);
@@ -77069,8 +77255,8 @@ SQLITE_PRIVATE int sqlite3CodeSubselect(
         sqlite3ReleaseTempReg(pParse, r1);
         sqlite3ReleaseTempReg(pParse, r2);
       }
-      if( !isRowid ){
-        sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO);
+      if( pKeyInfo ){
+        sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO_HANDOFF);
       }
       break;
     }
@@ -77096,11 +77282,11 @@ SQLITE_PRIVATE int sqlite3CodeSubselect(
       sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
       if( pExpr->op==TK_SELECT ){
         dest.eDest = SRT_Mem;
-        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
+        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iSDParm);
         VdbeComment((v, "Init subquery result"));
       }else{
         dest.eDest = SRT_Exists;
-        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
+        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iSDParm);
         VdbeComment((v, "Init EXISTS result"));
       }
       sqlite3ExprDelete(pParse->db, pSel->pLimit);
@@ -77110,7 +77296,7 @@ SQLITE_PRIVATE int sqlite3CodeSubselect(
       if( sqlite3Select(pParse, pSel, &dest) ){
         return 0;
       }
-      rReg = dest.iParm;
+      rReg = dest.iSDParm;
       ExprSetIrreducible(pExpr);
       break;
     }
@@ -77357,7 +77543,7 @@ SQLITE_PRIVATE void sqlite3ExprCacheStore(Parse *pParse, int iTab, int iCol, int
   ** for testing only - to verify that SQLite always gets the same answer
   ** with and without the column cache.
   */
-  if( pParse->db->flags & SQLITE_ColumnCache ) return;
+  if( OptimizationDisabled(pParse->db, SQLITE_ColumnCache) ) return;
 
   /* First replace any existing entry.
   **
@@ -77554,8 +77740,8 @@ SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, in
 SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){
   int i;
   struct yColCache *p;
-  if( NEVER(iFrom==iTo) ) return;
-  sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
+  assert( iFrom>=iTo+nReg || iFrom+nReg<=iTo );
+  sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg-1);
   for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
     int x = p->iReg;
     if( x>=iFrom && x<iFrom+nReg ){
@@ -77564,18 +77750,6 @@ SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int n
   }
 }
 
-/*
-** Generate code to copy content from registers iFrom...iFrom+nReg-1
-** over to iTo..iTo+nReg-1.
-*/
-SQLITE_PRIVATE void sqlite3ExprCodeCopy(Parse *pParse, int iFrom, int iTo, int nReg){
-  int i;
-  if( NEVER(iFrom==iTo) ) return;
-  for(i=0; i<nReg; i++){
-    sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, iFrom+i, iTo+i);
-  }
-}
-
 #if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
 /*
 ** Return true if any register in the range iFrom..iTo (inclusive)
@@ -77642,15 +77816,20 @@ SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target)
       /* Otherwise, fall thru into the TK_COLUMN case */
     }
     case TK_COLUMN: {
-      if( pExpr->iTable<0 ){
-        /* This only happens when coding check constraints */
-        assert( pParse->ckBase>0 );
-        inReg = pExpr->iColumn + pParse->ckBase;
-      }else{
-        inReg = sqlite3ExprCodeGetColumn(pParse, pExpr->pTab,
-                                 pExpr->iColumn, pExpr->iTable, target,
-                                 pExpr->op2);
+      int iTab = pExpr->iTable;
+      if( iTab<0 ){
+        if( pParse->ckBase>0 ){
+          /* Generating CHECK constraints or inserting into partial index */
+          inReg = pExpr->iColumn + pParse->ckBase;
+          break;
+        }else{
+          /* Deleting from a partial index */
+          iTab = pParse->iPartIdxTab;
+        }
       }
+      inReg = sqlite3ExprCodeGetColumn(pParse, pExpr->pTab,
+                               pExpr->iColumn, iTab, target,
+                               pExpr->op2);
       break;
     }
     case TK_INTEGER: {
@@ -78047,6 +78226,7 @@ SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target)
       sqlite3ReleaseTempReg(pParse, r4);
       break;
     }
+    case TK_COLLATE: 
     case TK_UPLUS: {
       inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
       break;
@@ -78213,7 +78393,8 @@ SQLITE_PRIVATE int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target)
         sqlite3VdbeAddOp4(
             v, OP_Halt, SQLITE_OK, OE_Ignore, 0, pExpr->u.zToken,0);
       }else{
-        sqlite3HaltConstraint(pParse, pExpr->affinity, pExpr->u.zToken, 0);
+        sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_TRIGGER,
+                              pExpr->affinity, pExpr->u.zToken, 0);
       }
 
       break;
@@ -78416,6 +78597,12 @@ SQLITE_PRIVATE void sqlite3ExplainExpr(Vdbe *pOut, Expr *pExpr){
     case TK_ISNULL:  zUniOp = "ISNULL"; break;
     case TK_NOTNULL: zUniOp = "NOTNULL"; break;
 
+    case TK_COLLATE: {
+      sqlite3ExplainExpr(pOut, pExpr->pLeft);
+      sqlite3ExplainPrintf(pOut,".COLLATE(%s)",pExpr->u.zToken);
+      break;
+    }
+
     case TK_AGG_FUNCTION:
     case TK_CONST_FUNC:
     case TK_FUNCTION: {
@@ -78425,9 +78612,12 @@ SQLITE_PRIVATE void sqlite3ExplainExpr(Vdbe *pOut, Expr *pExpr){
       }else{
         pFarg = pExpr->x.pList;
       }
-      sqlite3ExplainPrintf(pOut, "%sFUNCTION:%s(",
-                           op==TK_AGG_FUNCTION ? "AGG_" : "",
-                           pExpr->u.zToken);
+      if( op==TK_AGG_FUNCTION ){
+        sqlite3ExplainPrintf(pOut, "AGG_FUNCTION%d:%s(",
+                             pExpr->op2, pExpr->u.zToken);
+      }else{
+        sqlite3ExplainPrintf(pOut, "FUNCTION:%s(", pExpr->u.zToken);
+      }
       if( pFarg ){
         sqlite3ExplainExprList(pOut, pFarg);
       }
@@ -78550,6 +78740,12 @@ SQLITE_PRIVATE void sqlite3ExplainExprList(Vdbe *pOut, ExprList *pList){
       sqlite3ExplainPush(pOut);
       sqlite3ExplainExpr(pOut, pList->a[i].pExpr);
       sqlite3ExplainPop(pOut);
+      if( pList->a[i].zName ){
+        sqlite3ExplainPrintf(pOut, " AS %s", pList->a[i].zName);
+      }
+      if( pList->a[i].bSpanIsTab ){
+        sqlite3ExplainPrintf(pOut, " (%s)", pList->a[i].zSpan);
+      }
       if( i<pList->nExpr-1 ){
         sqlite3ExplainNL(pOut);
       }
@@ -78631,6 +78827,9 @@ static int evalConstExpr(Walker *pWalker, Expr *pExpr){
     case TK_REGISTER: {
       return WRC_Prune;
     }
+    case TK_COLLATE: {
+      return WRC_Continue;
+    }
     case TK_FUNCTION:
     case TK_AGG_FUNCTION:
     case TK_CONST_FUNC: {
@@ -78652,9 +78851,11 @@ static int evalConstExpr(Walker *pWalker, Expr *pExpr){
   }
   if( isAppropriateForFactoring(pExpr) ){
     int r1 = ++pParse->nMem;
-    int r2;
-    r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
-    if( NEVER(r1!=r2) ) sqlite3ReleaseTempReg(pParse, r1);
+    int r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1);
+    /* If r2!=r1, it means that register r1 is never used.  That is harmless
+    ** but suboptimal, so we want to know about the situation to fix it.
+    ** Hence the following assert: */
+    assert( r2==r1 );
     pExpr->op2 = pExpr->op;
     pExpr->op = TK_REGISTER;
     pExpr->iTable = r2;
@@ -78682,9 +78883,9 @@ static int evalConstExpr(Walker *pWalker, Expr *pExpr){
 SQLITE_PRIVATE void sqlite3ExprCodeConstants(Parse *pParse, Expr *pExpr){
   Walker w;
   if( pParse->cookieGoto ) return;
-  if( (pParse->db->flags & SQLITE_FactorOutConst)!=0 ) return;
+  if( OptimizationDisabled(pParse->db, SQLITE_FactorOutConst) ) return;
+  memset(&w, 0, sizeof(w));
   w.xExprCallback = evalConstExpr;
-  w.xSelectCallback = 0;
   w.pParse = pParse;
   sqlite3WalkExpr(&w, pExpr);
 }
@@ -78756,6 +78957,7 @@ static void exprCodeBetween(
   compRight.pLeft = &exprX;
   compRight.pRight = pExpr->x.pList->a[1].pExpr;
   exprX.iTable = sqlite3ExprCodeTemp(pParse, &exprX, &regFree1);
+  exprX.op2 = exprX.op;
   exprX.op = TK_REGISTER;
   if( jumpIfTrue ){
     sqlite3ExprIfTrue(pParse, &exprAnd, dest, jumpIfNull);
@@ -78797,7 +78999,7 @@ SQLITE_PRIVATE void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int
   int r1, r2;
 
   assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
-  if( NEVER(v==0) )     return;  /* Existance of VDBE checked by caller */
+  if( NEVER(v==0) )     return;  /* Existence of VDBE checked by caller */
   if( NEVER(pExpr==0) ) return;  /* No way this can happen */
   op = pExpr->op;
   switch( op ){
@@ -78917,7 +79119,7 @@ SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int
   int r1, r2;
 
   assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 );
-  if( NEVER(v==0) ) return; /* Existance of VDBE checked by caller */
+  if( NEVER(v==0) ) return; /* Existence of VDBE checked by caller */
   if( pExpr==0 )    return;
 
   /* The value of pExpr->op and op are related as follows:
@@ -79051,6 +79253,12 @@ SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int
 ** by a COLLATE operator at the top level.  Return 2 if there are differences
 ** other than the top-level COLLATE operator.
 **
+** If any subelement of pB has Expr.iTable==(-1) then it is allowed
+** to compare equal to an equivalent element in pA with Expr.iTable==iTab.
+**
+** The pA side might be using TK_REGISTER.  If that is the case and pB is
+** not using TK_REGISTER but is otherwise equivalent, then still return 0.
+**
 ** Sometimes this routine will return 2 even if the two expressions
 ** really are equivalent.  If we cannot prove that the expressions are
 ** identical, we return 2 just to be safe.  So if this routine
@@ -79061,7 +79269,7 @@ SQLITE_PRIVATE void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int
 ** just might result in some slightly slower code.  But returning
 ** an incorrect 0 or 1 could lead to a malfunction.
 */
-SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB){
+SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB, int iTab){
   if( pA==0||pB==0 ){
     return pB==pA ? 0 : 2;
   }
@@ -79071,11 +79279,22 @@ SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB){
     return 2;
   }
   if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 2;
-  if( pA->op!=pB->op ) return 2;
-  if( sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 2;
-  if( sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 2;
-  if( sqlite3ExprListCompare(pA->x.pList, pB->x.pList) ) return 2;
-  if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 2;
+  if( pA->op!=pB->op && (pA->op!=TK_REGISTER || pA->op2!=pB->op) ){
+    if( pA->op==TK_COLLATE && sqlite3ExprCompare(pA->pLeft, pB, iTab)<2 ){
+      return 1;
+    }
+    if( pB->op==TK_COLLATE && sqlite3ExprCompare(pA, pB->pLeft, iTab)<2 ){
+      return 1;
+    }
+    return 2;
+  }
+  if( sqlite3ExprCompare(pA->pLeft, pB->pLeft, iTab) ) return 2;
+  if( sqlite3ExprCompare(pA->pRight, pB->pRight, iTab) ) return 2;
+  if( sqlite3ExprListCompare(pA->x.pList, pB->x.pList, iTab) ) return 2;
+  if( pA->iColumn!=pB->iColumn ) return 2;
+  if( pA->iTable!=pB->iTable 
+   && pA->op!=TK_REGISTER
+   && (pA->iTable!=iTab || NEVER(pB->iTable>=0)) ) return 2;
   if( ExprHasProperty(pA, EP_IntValue) ){
     if( !ExprHasProperty(pB, EP_IntValue) || pA->u.iValue!=pB->u.iValue ){
       return 2;
@@ -79083,11 +79302,9 @@ SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB){
   }else if( pA->op!=TK_COLUMN && ALWAYS(pA->op!=TK_AGG_COLUMN) && pA->u.zToken){
     if( ExprHasProperty(pB, EP_IntValue) || NEVER(pB->u.zToken==0) ) return 2;
     if( strcmp(pA->u.zToken,pB->u.zToken)!=0 ){
-      return 2;
+      return pA->op==TK_COLLATE ? 1 : 2;
     }
   }
-  if( (pA->flags & EP_ExpCollate)!=(pB->flags & EP_ExpCollate) ) return 1;
-  if( (pA->flags & EP_ExpCollate)!=0 && pA->pColl!=pB->pColl ) return 2;
   return 0;
 }
 
@@ -79095,6 +79312,9 @@ SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB){
 ** Compare two ExprList objects.  Return 0 if they are identical and 
 ** non-zero if they differ in any way.
 **
+** If any subelement of pB has Expr.iTable==(-1) then it is allowed
+** to compare equal to an equivalent element in pA with Expr.iTable==iTab.
+**
 ** This routine might return non-zero for equivalent ExprLists.  The
 ** only consequence will be disabled optimizations.  But this routine
 ** must never return 0 if the two ExprList objects are different, or
@@ -79103,7 +79323,7 @@ SQLITE_PRIVATE int sqlite3ExprCompare(Expr *pA, Expr *pB){
 ** Two NULL pointers are considered to be the same.  But a NULL pointer
 ** always differs from a non-NULL pointer.
 */
-SQLITE_PRIVATE int sqlite3ExprListCompare(ExprList *pA, ExprList *pB){
+SQLITE_PRIVATE int sqlite3ExprListCompare(ExprList *pA, ExprList *pB, int iTab){
   int i;
   if( pA==0 && pB==0 ) return 0;
   if( pA==0 || pB==0 ) return 1;
@@ -79112,44 +79332,105 @@ SQLITE_PRIVATE int sqlite3ExprListCompare(ExprList *pA, ExprList *pB){
     Expr *pExprA = pA->a[i].pExpr;
     Expr *pExprB = pB->a[i].pExpr;
     if( pA->a[i].sortOrder!=pB->a[i].sortOrder ) return 1;
-    if( sqlite3ExprCompare(pExprA, pExprB) ) return 1;
+    if( sqlite3ExprCompare(pExprA, pExprB, iTab) ) return 1;
   }
   return 0;
 }
 
 /*
-** This is the expression callback for sqlite3FunctionUsesOtherSrc().
+** Return true if we can prove the pE2 will always be true if pE1 is
+** true.  Return false if we cannot complete the proof or if pE2 might
+** be false.  Examples:
 **
-** Determine if an expression references any table other than one of the
-** tables in pWalker->u.pSrcList and abort if it does.
+**     pE1: x==5       pE2: x==5             Result: true
+**     pE1: x>0        pE2: x==5             Result: false
+**     pE1: x=21       pE2: x=21 OR y=43     Result: true
+**     pE1: x!=123     pE2: x IS NOT NULL    Result: true
+**     pE1: x!=?1      pE2: x IS NOT NULL    Result: true
+**     pE1: x IS NULL  pE2: x IS NOT NULL    Result: false
+**     pE1: x IS ?2    pE2: x IS NOT NULL    Reuslt: false
+**
+** When comparing TK_COLUMN nodes between pE1 and pE2, if pE2 has
+** Expr.iTable<0 then assume a table number given by iTab.
+**
+** When in doubt, return false.  Returning true might give a performance
+** improvement.  Returning false might cause a performance reduction, but
+** it will always give the correct answer and is hence always safe.
 */
-static int exprUsesOtherSrc(Walker *pWalker, Expr *pExpr){
-  if( pExpr->op==TK_COLUMN || pExpr->op==TK_AGG_COLUMN ){
-    int i;
-    SrcList *pSrc = pWalker->u.pSrcList;
-    for(i=0; i<pSrc->nSrc; i++){
-      if( pExpr->iTable==pSrc->a[i].iCursor ) return WRC_Continue;
-    }
-    return WRC_Abort;
-  }else{
-    return WRC_Continue;
+SQLITE_PRIVATE int sqlite3ExprImpliesExpr(Expr *pE1, Expr *pE2, int iTab){
+  if( sqlite3ExprCompare(pE1, pE2, iTab)==0 ){
+    return 1;
   }
+  if( pE2->op==TK_OR
+   && (sqlite3ExprImpliesExpr(pE1, pE2->pLeft, iTab)
+             || sqlite3ExprImpliesExpr(pE1, pE2->pRight, iTab) )
+  ){
+    return 1;
+  }
+  if( pE2->op==TK_NOTNULL
+   && sqlite3ExprCompare(pE1->pLeft, pE2->pLeft, iTab)==0
+   && (pE1->op!=TK_ISNULL && pE1->op!=TK_IS)
+  ){
+    return 1;
+  }
+  return 0;
 }
 
 /*
-** Determine if any of the arguments to the pExpr Function references
-** any SrcList other than pSrcList.  Return true if they do.  Return
-** false if pExpr has no argument or has only constant arguments or
-** only references tables named in pSrcList.
+** An instance of the following structure is used by the tree walker
+** to count references to table columns in the arguments of an 
+** aggregate function, in order to implement the
+** sqlite3FunctionThisSrc() routine.
 */
-static int sqlite3FunctionUsesOtherSrc(Expr *pExpr, SrcList *pSrcList){
+struct SrcCount {
+  SrcList *pSrc;   /* One particular FROM clause in a nested query */
+  int nThis;       /* Number of references to columns in pSrcList */
+  int nOther;      /* Number of references to columns in other FROM clauses */
+};
+
+/*
+** Count the number of references to columns.
+*/
+static int exprSrcCount(Walker *pWalker, Expr *pExpr){
+  /* The NEVER() on the second term is because sqlite3FunctionUsesThisSrc()
+  ** is always called before sqlite3ExprAnalyzeAggregates() and so the
+  ** TK_COLUMNs have not yet been converted into TK_AGG_COLUMN.  If
+  ** sqlite3FunctionUsesThisSrc() is used differently in the future, the
+  ** NEVER() will need to be removed. */
+  if( pExpr->op==TK_COLUMN || NEVER(pExpr->op==TK_AGG_COLUMN) ){
+    int i;
+    struct SrcCount *p = pWalker->u.pSrcCount;
+    SrcList *pSrc = p->pSrc;
+    for(i=0; i<pSrc->nSrc; i++){
+      if( pExpr->iTable==pSrc->a[i].iCursor ) break;
+    }
+    if( i<pSrc->nSrc ){
+      p->nThis++;
+    }else{
+      p->nOther++;
+    }
+  }
+  return WRC_Continue;
+}
+
+/*
+** Determine if any of the arguments to the pExpr Function reference
+** pSrcList.  Return true if they do.  Also return true if the function
+** has no arguments or has only constant arguments.  Return false if pExpr
+** references columns but not columns of tables found in pSrcList.
+*/
+SQLITE_PRIVATE int sqlite3FunctionUsesThisSrc(Expr *pExpr, SrcList *pSrcList){
   Walker w;
+  struct SrcCount cnt;
   assert( pExpr->op==TK_AGG_FUNCTION );
   memset(&w, 0, sizeof(w));
-  w.xExprCallback = exprUsesOtherSrc;
-  w.u.pSrcList = pSrcList;
-  if( sqlite3WalkExprList(&w, pExpr->x.pList)!=WRC_Continue ) return 1;
-  return 0;
+  w.xExprCallback = exprSrcCount;
+  w.u.pSrcCount = &cnt;
+  cnt.pSrc = pSrcList;
+  cnt.nThis = 0;
+  cnt.nOther = 0;
+  sqlite3WalkExprList(&w, pExpr->x.pList);
+  return cnt.nThis>0 || cnt.nOther==0;
 }
 
 /*
@@ -79268,14 +79549,14 @@ static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
     }
     case TK_AGG_FUNCTION: {
       if( (pNC->ncFlags & NC_InAggFunc)==0
-       && !sqlite3FunctionUsesOtherSrc(pExpr, pSrcList)
+       && pWalker->walkerDepth==pExpr->op2
       ){
         /* Check to see if pExpr is a duplicate of another aggregate 
         ** function that is already in the pAggInfo structure
         */
         struct AggInfo_func *pItem = pAggInfo->aFunc;
         for(i=0; i<pAggInfo->nFunc; i++, pItem++){
-          if( sqlite3ExprCompare(pItem->pExpr, pExpr)==0 ){
+          if( sqlite3ExprCompare(pItem->pExpr, pExpr, -1)==0 ){
             break;
           }
         }
@@ -79306,8 +79587,10 @@ static int analyzeAggregate(Walker *pWalker, Expr *pExpr){
         ExprSetIrreducible(pExpr);
         pExpr->iAgg = (i16)i;
         pExpr->pAggInfo = pAggInfo;
+        return WRC_Prune;
+      }else{
+        return WRC_Continue;
       }
-      return WRC_Prune;
     }
   }
   return WRC_Continue;
@@ -79319,9 +79602,10 @@ static int analyzeAggregatesInSelect(Walker *pWalker, Select *pSelect){
 }
 
 /*
-** Analyze the given expression looking for aggregate functions and
-** for variables that need to be added to the pParse->aAgg[] array.
-** Make additional entries to the pParse->aAgg[] array as necessary.
+** Analyze the pExpr expression looking for aggregate functions and
+** for variables that need to be added to AggInfo object that pNC->pAggInfo
+** points to.  Additional entries are made on the AggInfo object as
+** necessary.
 **
 ** This routine should only be called after the expression has been
 ** analyzed by sqlite3ResolveExprNames().
@@ -79834,7 +80118,7 @@ SQLITE_PRIVATE void sqlite3AlterRenameTable(
   assert( pSrc->nSrc==1 );
   assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
 
-  pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
+  pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]);
   if( !pTab ) goto exit_rename_table;
   iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
   zDb = db->aDb[iDb].zName;
@@ -80084,7 +80368,7 @@ SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
   ** If there is a NOT NULL constraint, then the default value for the
   ** column must not be NULL.
   */
-  if( pCol->isPrimKey ){
+  if( pCol->colFlags & COLFLAG_PRIMKEY ){
     sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
     return;
   }
@@ -80177,7 +80461,7 @@ SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *pParse, SrcList *pSrc){
   assert( pParse->pNewTable==0 );
   assert( sqlite3BtreeHoldsAllMutexes(db) );
   if( db->mallocFailed ) goto exit_begin_add_column;
-  pTab = sqlite3LocateTable(pParse, 0, pSrc->a[0].zName, pSrc->a[0].zDatabase);
+  pTab = sqlite3LocateTableItem(pParse, 0, &pSrc->a[0]);
   if( !pTab ) goto exit_begin_add_column;
 
 #ifndef SQLITE_OMIT_VIRTUALTABLE
@@ -80274,7 +80558,7 @@ exit_begin_add_column:
 ** The sqlite_stat2 table is not created or used unless the SQLite version
 ** is between 3.6.18 and 3.7.8, inclusive, and unless SQLite is compiled
 ** with SQLITE_ENABLE_STAT2.  The sqlite_stat2 table is deprecated.
-** The sqlite_stat2 table is superceded by sqlite_stat3, which is only
+** The sqlite_stat2 table is superseded by sqlite_stat3, which is only
 ** created and used by SQLite versions 3.7.9 and later and with
 ** SQLITE_ENABLE_STAT3 defined.  The fucntionality of sqlite_stat3
 ** is a superset of sqlite_stat2.  
@@ -80424,7 +80708,7 @@ static void openStatTable(
           "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
       );
       aRoot[i] = pParse->regRoot;
-      aCreateTbl[i] = 1;
+      aCreateTbl[i] = OPFLAG_P2ISREG;
     }else{
       /* The table already exists. If zWhere is not NULL, delete all entries 
       ** associated with the table zWhere. If zWhere is NULL, delete the
@@ -80504,12 +80788,11 @@ static void stat3Init(
   nRow = (tRowcnt)sqlite3_value_int64(argv[0]);
   mxSample = sqlite3_value_int(argv[1]);
   n = sizeof(*p) + sizeof(p->a[0])*mxSample;
-  p = sqlite3_malloc( n );
+  p = sqlite3MallocZero( n );
   if( p==0 ){
     sqlite3_result_error_nomem(context);
     return;
   }
-  memset(p, 0, n);
   p->a = (struct Stat3Sample*)&p[1];
   p->nRow = nRow;
   p->mxSample = mxSample;
@@ -80690,6 +80973,7 @@ static void analyzeOneTable(
   int endOfLoop;               /* The end of the loop */
   int jZeroRows = -1;          /* Jump from here if number of rows is zero */
   int iDb;                     /* Index of database containing pTab */
+  u8 needTableCnt = 1;         /* True to count the table */
   int regTabname = iMem++;     /* Register containing table name */
   int regIdxname = iMem++;     /* Register containing index name */
   int regStat1 = iMem++;       /* The stat column of sqlite_stat1 */
@@ -80722,7 +81006,7 @@ static void analyzeOneTable(
     /* Do not gather statistics on views or virtual tables */
     return;
   }
-  if( memcmp(pTab->zName, "sqlite_", 7)==0 ){
+  if( sqlite3_strnicmp(pTab->zName, "sqlite_", 7)==0 ){
     /* Do not gather statistics on system tables */
     return;
   }
@@ -80749,6 +81033,7 @@ static void analyzeOneTable(
     int *aChngAddr;              /* Array of jump instruction addresses */
 
     if( pOnlyIdx && pOnlyIdx!=pIdx ) continue;
+    if( pIdx->pPartIdxWhere==0 ) needTableCnt = 0;
     VdbeNoopComment((v, "Begin analysis of %s", pIdx->zName));
     nCol = pIdx->nColumn;
     aChngAddr = sqlite3DbMallocRaw(db, sizeof(int)*nCol);
@@ -80908,9 +81193,7 @@ static void analyzeOneTable(
     ** is never possible.
     */
     sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regStat1);
-    if( jZeroRows<0 ){
-      jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
-    }
+    jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
     for(i=0; i<nCol; i++){
       sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
       sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regStat1, regStat1);
@@ -80920,32 +81203,31 @@ static void analyzeOneTable(
       sqlite3VdbeAddOp1(v, OP_ToInt, regTemp);
       sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regStat1, regStat1);
     }
+    if( pIdx->pPartIdxWhere!=0 ) sqlite3VdbeJumpHere(v, jZeroRows);
     sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
     sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
     sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regNewRowid);
     sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
+    if( pIdx->pPartIdxWhere==0 ) sqlite3VdbeJumpHere(v, jZeroRows);
   }
 
-  /* If the table has no indices, create a single sqlite_stat1 entry
-  ** containing NULL as the index name and the row count as the content.
+  /* Create a single sqlite_stat1 entry containing NULL as the index
+  ** name and the row count as the content.
   */
-  if( pTab->pIndex==0 ){
+  if( pOnlyIdx==0 && needTableCnt ){
     sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
     VdbeComment((v, "%s", pTab->zName));
     sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regStat1);
     sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
     jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, regStat1);
-  }else{
+    sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
+    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
+    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
+    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regNewRowid);
+    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
     sqlite3VdbeJumpHere(v, jZeroRows);
-    jZeroRows = sqlite3VdbeAddOp0(v, OP_Goto);
   }
-  sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
-  sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
-  sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
-  sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regNewRowid);
-  sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
   if( pParse->nMem<regRec ) pParse->nMem = regRec;
-  sqlite3VdbeJumpHere(v, jZeroRows);
 }
 
 
@@ -81128,11 +81410,13 @@ static int analysisLoader(void *pData, int argc, char **argv, char **NotUsed){
       v = v*10 + c - '0';
       z++;
     }
-    if( i==0 ) pTable->nRowEst = v;
-    if( pIndex==0 ) break;
+    if( i==0 && (pIndex==0 || pIndex->pPartIdxWhere==0) ){
+      if( v>0 ) pTable->nRowEst = v;
+      if( pIndex==0 ) break;
+    }
     pIndex->aiRowEst[i] = v;
     if( *z==' ' ) z++;
-    if( memcmp(z, "unordered", 10)==0 ){
+    if( strcmp(z, "unordered")==0 ){
       pIndex->bUnordered = 1;
       break;
     }
@@ -81484,7 +81768,7 @@ static void attachFunc(
     }
   }
 
-  /* Allocate the new entry in the db->aDb[] array and initialise the schema
+  /* Allocate the new entry in the db->aDb[] array and initialize the schema
   ** hash tables.
   */
   if( db->aDb==db->aDbStatic ){
@@ -81501,7 +81785,7 @@ static void attachFunc(
 
   /* Open the database file. If the btree is successfully opened, use
   ** it to obtain the database schema. At this point the schema may
-  ** or may not be initialised.
+  ** or may not be initialized.
   */
   flags = db->openFlags;
   rc = sqlite3ParseUri(db->pVfs->zName, zFile, &flags, &pVfs, &zPath, &zErr);
@@ -81533,6 +81817,9 @@ static void attachFunc(
     sqlite3PagerLockingMode(pPager, db->dfltLockMode);
     sqlite3BtreeSecureDelete(aNew->pBt,
                              sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) );
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+    sqlite3BtreeSetPagerFlags(aNew->pBt, 3 | (db->flags & PAGER_FLAGS_MASK));
+#endif
   }
   aNew->safety_level = 3;
   aNew->zName = sqlite3DbStrDup(db, zName);
@@ -81809,6 +82096,7 @@ SQLITE_PRIVATE int sqlite3FixInit(
   assert( db->nDb>iDb );
   pFix->pParse = pParse;
   pFix->zDb = db->aDb[iDb].zName;
+  pFix->pSchema = db->aDb[iDb].pSchema;
   pFix->zType = zType;
   pFix->pName = pName;
   return 1;
@@ -81839,14 +82127,15 @@ SQLITE_PRIVATE int sqlite3FixSrcList(
   if( NEVER(pList==0) ) return 0;
   zDb = pFix->zDb;
   for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
-    if( pItem->zDatabase==0 ){
-      pItem->zDatabase = sqlite3DbStrDup(pFix->pParse->db, zDb);
-    }else if( sqlite3StrICmp(pItem->zDatabase,zDb)!=0 ){
+    if( pItem->zDatabase && sqlite3StrICmp(pItem->zDatabase, zDb) ){
       sqlite3ErrorMsg(pFix->pParse,
          "%s %T cannot reference objects in database %s",
          pFix->zType, pFix->pName, pItem->zDatabase);
       return 1;
     }
+    sqlite3DbFree(pFix->pParse->db, pItem->zDatabase);
+    pItem->zDatabase = 0;
+    pItem->pSchema = pFix->pSchema;
 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER)
     if( sqlite3FixSelect(pFix, pItem->pSelect) ) return 1;
     if( sqlite3FixExpr(pFix, pItem->pOn) ) return 1;
@@ -82312,6 +82601,7 @@ SQLITE_PRIVATE void sqlite3FinishCoding(Parse *pParse){
   sqlite3 *db;
   Vdbe *v;
 
+  assert( pParse->pToplevel==0 );
   db = pParse->db;
   if( db->mallocFailed ) return;
   if( pParse->nested ) return;
@@ -82504,6 +82794,31 @@ SQLITE_PRIVATE Table *sqlite3LocateTable(
   return p;
 }
 
+/*
+** Locate the table identified by *p.
+**
+** This is a wrapper around sqlite3LocateTable(). The difference between
+** sqlite3LocateTable() and this function is that this function restricts
+** the search to schema (p->pSchema) if it is not NULL. p->pSchema may be
+** non-NULL if it is part of a view or trigger program definition. See
+** sqlite3FixSrcList() for details.
+*/
+SQLITE_PRIVATE Table *sqlite3LocateTableItem(
+  Parse *pParse, 
+  int isView, 
+  struct SrcList_item *p
+){
+  const char *zDb;
+  assert( p->pSchema==0 || p->zDatabase==0 );
+  if( p->pSchema ){
+    int iDb = sqlite3SchemaToIndex(pParse->db, p->pSchema);
+    zDb = pParse->db->aDb[iDb].zName;
+  }else{
+    zDb = p->zDatabase;
+  }
+  return sqlite3LocateTable(pParse, isView, p->zName, zDb);
+}
+
 /*
 ** Locate the in-memory structure that describes 
 ** a particular index given the name of that index
@@ -82541,6 +82856,7 @@ static void freeIndex(sqlite3 *db, Index *p){
 #ifndef SQLITE_OMIT_ANALYZE
   sqlite3DeleteIndexSamples(db, p);
 #endif
+  sqlite3ExprDelete(db, p->pPartIdxWhere);
   sqlite3DbFree(db, p->zColAff);
   sqlite3DbFree(db, p);
 }
@@ -82719,7 +83035,7 @@ SQLITE_PRIVATE void sqlite3DeleteTable(sqlite3 *db, Table *pTable){
     if( !db || db->pnBytesFreed==0 ){
       char *zName = pIndex->zName; 
       TESTONLY ( Index *pOld = ) sqlite3HashInsert(
-	  &pIndex->pSchema->idxHash, zName, sqlite3Strlen30(zName), 0
+         &pIndex->pSchema->idxHash, zName, sqlite3Strlen30(zName), 0
       );
       assert( db==0 || sqlite3SchemaMutexHeld(db, 0, pIndex->pSchema) );
       assert( pOld==pIndex || pOld==0 );
@@ -83354,7 +83670,7 @@ SQLITE_PRIVATE void sqlite3AddPrimaryKey(
   pTab->tabFlags |= TF_HasPrimaryKey;
   if( pList==0 ){
     iCol = pTab->nCol - 1;
-    pTab->aCol[iCol].isPrimKey = 1;
+    pTab->aCol[iCol].colFlags |= COLFLAG_PRIMKEY;
   }else{
     for(i=0; i<pList->nExpr; i++){
       for(iCol=0; iCol<pTab->nCol; iCol++){
@@ -83363,7 +83679,7 @@ SQLITE_PRIVATE void sqlite3AddPrimaryKey(
         }
       }
       if( iCol<pTab->nCol ){
-        pTab->aCol[iCol].isPrimKey = 1;
+        pTab->aCol[iCol].colFlags |= COLFLAG_PRIMKEY;
       }
     }
     if( pList->nExpr>1 ) iCol = -1;
@@ -83384,7 +83700,8 @@ SQLITE_PRIVATE void sqlite3AddPrimaryKey(
 #endif
   }else{
     Index *p;
-    p = sqlite3CreateIndex(pParse, 0, 0, 0, pList, onError, 0, 0, sortOrder, 0);
+    p = sqlite3CreateIndex(pParse, 0, 0, 0, pList, onError, 0,
+                           0, sortOrder, 0);
     if( p ){
       p->autoIndex = 2;
     }
@@ -83435,6 +83752,7 @@ SQLITE_PRIVATE void sqlite3AddCollateType(Parse *pParse, Token *pToken){
 
   if( sqlite3LocateCollSeq(pParse, zColl) ){
     Index *pIdx;
+    sqlite3DbFree(db, p->aCol[i].zColl);
     p->aCol[i].zColl = zColl;
   
     /* If the column is declared as "<name> PRIMARY KEY COLLATE <type>",
@@ -83480,10 +83798,7 @@ SQLITE_PRIVATE CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName){
 
   pColl = sqlite3FindCollSeq(db, enc, zName, initbusy);
   if( !initbusy && (!pColl || !pColl->xCmp) ){
-    pColl = sqlite3GetCollSeq(db, enc, pColl, zName);
-    if( !pColl ){
-      sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
-    }
+    pColl = sqlite3GetCollSeq(pParse, enc, pColl, zName);
   }
 
   return pColl;
@@ -83681,26 +83996,7 @@ SQLITE_PRIVATE void sqlite3EndTable(
   /* Resolve names in all CHECK constraint expressions.
   */
   if( p->pCheck ){
-    SrcList sSrc;                   /* Fake SrcList for pParse->pNewTable */
-    NameContext sNC;                /* Name context for pParse->pNewTable */
-    ExprList *pList;                /* List of all CHECK constraints */
-    int i;                          /* Loop counter */
-
-    memset(&sNC, 0, sizeof(sNC));
-    memset(&sSrc, 0, sizeof(sSrc));
-    sSrc.nSrc = 1;
-    sSrc.a[0].zName = p->zName;
-    sSrc.a[0].pTab = p;
-    sSrc.a[0].iCursor = -1;
-    sNC.pParse = pParse;
-    sNC.pSrcList = &sSrc;
-    sNC.ncFlags = NC_IsCheck;
-    pList = p->pCheck;
-    for(i=0; i<pList->nExpr; i++){
-      if( sqlite3ResolveExprNames(&sNC, pList->a[i].pExpr) ){
-        return;
-      }
-    }
+    sqlite3ResolveSelfReference(pParse, p, NC_IsCheck, 0, p->pCheck);
   }
 #endif /* !defined(SQLITE_OMIT_CHECK) */
 
@@ -83766,7 +84062,7 @@ SQLITE_PRIVATE void sqlite3EndTable(
 
       assert(pParse->nTab==1);
       sqlite3VdbeAddOp3(v, OP_OpenWrite, 1, pParse->regRoot, iDb);
-      sqlite3VdbeChangeP5(v, 1);
+      sqlite3VdbeChangeP5(v, OPFLAG_P2ISREG);
       pParse->nTab = 2;
       sqlite3SelectDestInit(&dest, SRT_Table, 1);
       sqlite3Select(pParse, pSelect, &dest);
@@ -84182,6 +84478,7 @@ static void destroyTable(Parse *pParse, Table *pTab){
       return;
     }else{
       int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
+      assert( iDb>=0 && iDb<pParse->db->nDb );
       destroyRootPage(pParse, iLargest, iDb);
       iDestroyed = iLargest;
     }
@@ -84261,7 +84558,7 @@ SQLITE_PRIVATE void sqlite3CodeDropTable(Parse *pParse, Table *pTab, int iDb, in
   /* Drop all SQLITE_MASTER table and index entries that refer to the
   ** table. The program name loops through the master table and deletes
   ** every row that refers to a table of the same name as the one being
-  ** dropped. Triggers are handled seperately because a trigger can be
+  ** dropped. Triggers are handled separately because a trigger can be
   ** created in the temp database that refers to a table in another
   ** database.
   */
@@ -84299,8 +84596,7 @@ SQLITE_PRIVATE void sqlite3DropTable(Parse *pParse, SrcList *pName, int isView,
   assert( pParse->nErr==0 );
   assert( pName->nSrc==1 );
   if( noErr ) db->suppressErr++;
-  pTab = sqlite3LocateTable(pParse, isView, 
-                            pName->a[0].zName, pName->a[0].zDatabase);
+  pTab = sqlite3LocateTableItem(pParse, isView, &pName->a[0]);
   if( noErr ) db->suppressErr--;
 
   if( pTab==0 ){
@@ -84552,11 +84848,9 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
   int addr1;                     /* Address of top of loop */
   int addr2;                     /* Address to jump to for next iteration */
   int tnum;                      /* Root page of index */
+  int iPartIdxLabel;             /* Jump to this label to skip a row */
   Vdbe *v;                       /* Generate code into this virtual machine */
   KeyInfo *pKey;                 /* KeyInfo for index */
-#ifdef SQLITE_OMIT_MERGE_SORT
-  int regIdxKey;                 /* Registers containing the index key */
-#endif
   int regRecord;                 /* Register holding assemblied index record */
   sqlite3 *db = pParse->db;      /* The database connection */
   int iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);
@@ -84582,17 +84876,11 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
   pKey = sqlite3IndexKeyinfo(pParse, pIndex);
   sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb, 
                     (char *)pKey, P4_KEYINFO_HANDOFF);
-  if( memRootPage>=0 ){
-    sqlite3VdbeChangeP5(v, 1);
-  }
+  sqlite3VdbeChangeP5(v, OPFLAG_BULKCSR|((memRootPage>=0)?OPFLAG_P2ISREG:0));
 
-#ifndef SQLITE_OMIT_MERGE_SORT
   /* Open the sorter cursor if we are to use one. */
   iSorter = pParse->nTab++;
   sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, 0, (char*)pKey, P4_KEYINFO);
-#else
-  iSorter = iTab;
-#endif
 
   /* Open the table. Loop through all rows of the table, inserting index
   ** records into the sorter. */
@@ -84600,9 +84888,9 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
   addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
   regRecord = sqlite3GetTempReg(pParse);
 
-#ifndef SQLITE_OMIT_MERGE_SORT
-  sqlite3GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1);
+  sqlite3GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1, &iPartIdxLabel);
   sqlite3VdbeAddOp2(v, OP_SorterInsert, iSorter, regRecord);
+  sqlite3VdbeResolveLabel(v, iPartIdxLabel);
   sqlite3VdbeAddOp2(v, OP_Next, iTab, addr1+1);
   sqlite3VdbeJumpHere(v, addr1);
   addr1 = sqlite3VdbeAddOp2(v, OP_SorterSort, iSorter, 0);
@@ -84611,8 +84899,8 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
     sqlite3VdbeAddOp2(v, OP_Goto, 0, j2);
     addr2 = sqlite3VdbeCurrentAddr(v);
     sqlite3VdbeAddOp3(v, OP_SorterCompare, iSorter, j2, regRecord);
-    sqlite3HaltConstraint(
-        pParse, OE_Abort, "indexed columns are not unique", P4_STATIC
+    sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_UNIQUE,
+        OE_Abort, "indexed columns are not unique", P4_STATIC
     );
   }else{
     addr2 = sqlite3VdbeCurrentAddr(v);
@@ -84620,30 +84908,6 @@ static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
   sqlite3VdbeAddOp2(v, OP_SorterData, iSorter, regRecord);
   sqlite3VdbeAddOp3(v, OP_IdxInsert, iIdx, regRecord, 1);
   sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
-#else
-  regIdxKey = sqlite3GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1);
-  addr2 = addr1 + 1;
-  if( pIndex->onError!=OE_None ){
-    const int regRowid = regIdxKey + pIndex->nColumn;
-    const int j2 = sqlite3VdbeCurrentAddr(v) + 2;
-    void * const pRegKey = SQLITE_INT_TO_PTR(regIdxKey);
-
-    /* The registers accessed by the OP_IsUnique opcode were allocated
-    ** using sqlite3GetTempRange() inside of the sqlite3GenerateIndexKey()
-    ** call above. Just before that function was freed they were released
-    ** (made available to the compiler for reuse) using 
-    ** sqlite3ReleaseTempRange(). So in some ways having the OP_IsUnique
-    ** opcode use the values stored within seems dangerous. However, since
-    ** we can be sure that no other temp registers have been allocated
-    ** since sqlite3ReleaseTempRange() was called, it is safe to do so.
-    */
-    sqlite3VdbeAddOp4(v, OP_IsUnique, iIdx, j2, regRowid, pRegKey, P4_INT32);
-    sqlite3HaltConstraint(
-        pParse, OE_Abort, "indexed columns are not unique", P4_STATIC);
-  }
-  sqlite3VdbeAddOp3(v, OP_IdxInsert, iIdx, regRecord, 0);
-  sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
-#endif
   sqlite3ReleaseTempReg(pParse, regRecord);
   sqlite3VdbeAddOp2(v, OP_SorterNext, iSorter, addr2);
   sqlite3VdbeJumpHere(v, addr1);
@@ -84677,7 +84941,7 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
   ExprList *pList,   /* A list of columns to be indexed */
   int onError,       /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
   Token *pStart,     /* The CREATE token that begins this statement */
-  Token *pEnd,       /* The ")" that closes the CREATE INDEX statement */
+  Expr *pPIWhere,    /* WHERE clause for partial indices */
   int sortOrder,     /* Sort order of primary key when pList==NULL */
   int ifNotExist     /* Omit error if index already exists */
 ){
@@ -84699,7 +84963,6 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
   int nExtra = 0;
   char *zExtra;
 
-  assert( pStart==0 || pEnd!=0 ); /* pEnd must be non-NULL if pStart is */
   assert( pParse->nErr==0 );      /* Never called with prior errors */
   if( db->mallocFailed || IN_DECLARE_VTAB ){
     goto exit_create_index;
@@ -84723,7 +84986,7 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
     assert( pName && pName->z );
 
 #ifndef SQLITE_OMIT_TEMPDB
-    /* If the index name was unqualified, check if the the table
+    /* If the index name was unqualified, check if the table
     ** is a temp table. If so, set the database to 1. Do not do this
     ** if initialising a database schema.
     */
@@ -84742,10 +85005,15 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
       ** sqlite3FixSrcList can never fail. */
       assert(0);
     }
-    pTab = sqlite3LocateTable(pParse, 0, pTblName->a[0].zName, 
-        pTblName->a[0].zDatabase);
-    if( !pTab || db->mallocFailed ) goto exit_create_index;
-    assert( db->aDb[iDb].pSchema==pTab->pSchema );
+    pTab = sqlite3LocateTableItem(pParse, 0, &pTblName->a[0]);
+    assert( db->mallocFailed==0 || pTab==0 );
+    if( pTab==0 ) goto exit_create_index;
+    if( iDb==1 && db->aDb[iDb].pSchema!=pTab->pSchema ){
+      sqlite3ErrorMsg(pParse, 
+           "cannot create a TEMP index on non-TEMP table \"%s\"",
+           pTab->zName);
+      goto exit_create_index;
+    }
   }else{
     assert( pName==0 );
     assert( pStart==0 );
@@ -84758,7 +85026,7 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
   assert( pTab!=0 );
   assert( pParse->nErr==0 );
   if( sqlite3StrNICmp(pTab->zName, "sqlite_", 7)==0 
-       && memcmp(&pTab->zName[7],"altertab_",9)!=0 ){
+       && sqlite3StrNICmp(&pTab->zName[7],"altertab_",9)!=0 ){
     sqlite3ErrorMsg(pParse, "table %s may not be indexed", pTab->zName);
     goto exit_create_index;
   }
@@ -84855,12 +85123,8 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
   for(i=0; i<pList->nExpr; i++){
     Expr *pExpr = pList->a[i].pExpr;
     if( pExpr ){
-      CollSeq *pColl = pExpr->pColl;
-      /* Either pColl!=0 or there was an OOM failure.  But if an OOM
-      ** failure we have quit before reaching this point. */
-      if( ALWAYS(pColl) ){
-        nExtra += (1 + sqlite3Strlen30(pColl->zName));
-      }
+      assert( pExpr->op==TK_COLLATE );
+      nExtra += (1 + sqlite3Strlen30(pExpr->u.zToken));
     }
   }
 
@@ -84895,8 +85159,14 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
   pIndex->pTable = pTab;
   pIndex->nColumn = pList->nExpr;
   pIndex->onError = (u8)onError;
+  pIndex->uniqNotNull = onError==OE_Abort;
   pIndex->autoIndex = (u8)(pName==0);
   pIndex->pSchema = db->aDb[iDb].pSchema;
+  if( pPIWhere ){
+    sqlite3ResolveSelfReference(pParse, pTab, NC_PartIdx, pPIWhere, 0);
+    pIndex->pPartIdxWhere = pPIWhere;
+    pPIWhere = 0;
+  }
   assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
 
   /* Check to see if we should honor DESC requests on index columns
@@ -84933,14 +85203,10 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
       goto exit_create_index;
     }
     pIndex->aiColumn[i] = j;
-    /* Justification of the ALWAYS(pListItem->pExpr->pColl):  Because of
-    ** the way the "idxlist" non-terminal is constructed by the parser,
-    ** if pListItem->pExpr is not null then either pListItem->pExpr->pColl
-    ** must exist or else there must have been an OOM error.  But if there
-    ** was an OOM error, we would never reach this point. */
-    if( pListItem->pExpr && ALWAYS(pListItem->pExpr->pColl) ){
+    if( pListItem->pExpr ){
       int nColl;
-      zColl = pListItem->pExpr->pColl->zName;
+      assert( pListItem->pExpr->op==TK_COLLATE );
+      zColl = pListItem->pExpr->u.zToken;
       nColl = sqlite3Strlen30(zColl) + 1;
       assert( nExtra>=nColl );
       memcpy(zExtra, zColl, nColl);
@@ -84949,9 +85215,7 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
       nExtra -= nColl;
     }else{
       zColl = pTab->aCol[j].zColl;
-      if( !zColl ){
-        zColl = "BINARY";
-      }
+      if( !zColl ) zColl = "BINARY";
     }
     if( !db->init.busy && !sqlite3LocateCollSeq(pParse, zColl) ){
       goto exit_create_index;
@@ -84959,6 +85223,7 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
     pIndex->azColl[i] = zColl;
     requestedSortOrder = pListItem->sortOrder & sortOrderMask;
     pIndex->aSortOrder[i] = (u8)requestedSortOrder;
+    if( pTab->aCol[j].notNull==0 ) pIndex->uniqNotNull = 0;
   }
   sqlite3DefaultRowEst(pIndex);
 
@@ -85007,7 +85272,7 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
           ** However the ON CONFLICT clauses are different. If both this 
           ** constraint and the previous equivalent constraint have explicit
           ** ON CONFLICT clauses this is an error. Otherwise, use the
-          ** explicitly specified behaviour for the index.
+          ** explicitly specified behavior for the index.
           */
           if( !(pIdx->onError==OE_Default || pIndex->onError==OE_Default) ){
             sqlite3ErrorMsg(pParse, 
@@ -85057,7 +85322,7 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
   ** has just been created, it contains no data and the index initialization
   ** step can be skipped.
   */
-  else{ /* if( db->init.busy==0 ) */
+  else if( pParse->nErr==0 ){
     Vdbe *v;
     char *zStmt;
     int iMem = ++pParse->nMem;
@@ -85075,12 +85340,11 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
     ** the zStmt variable
     */
     if( pStart ){
-      assert( pEnd!=0 );
+      int n = (int)(pParse->sLastToken.z - pName->z) + pParse->sLastToken.n;
+      if( pName->z[n-1]==';' ) n--;
       /* A named index with an explicit CREATE INDEX statement */
       zStmt = sqlite3MPrintf(db, "CREATE%s INDEX %.*s",
-        onError==OE_None ? "" : " UNIQUE",
-        (int)(pEnd->z - pName->z) + 1,
-        pName->z);
+        onError==OE_None ? "" : " UNIQUE", n, pName->z);
     }else{
       /* An automatic index created by a PRIMARY KEY or UNIQUE constraint */
       /* zStmt = sqlite3MPrintf(""); */
@@ -85136,10 +85400,8 @@ SQLITE_PRIVATE Index *sqlite3CreateIndex(
 
   /* Clean up before exiting */
 exit_create_index:
-  if( pIndex ){
-    sqlite3DbFree(db, pIndex->zColAff);
-    sqlite3DbFree(db, pIndex);
-  }
+  if( pIndex ) freeIndex(db, pIndex);
+  sqlite3ExprDelete(db, pPIWhere);
   sqlite3ExprListDelete(db, pList);
   sqlite3SrcListDelete(db, pTblName);
   sqlite3DbFree(db, zName);
@@ -85390,7 +85652,7 @@ SQLITE_PRIVATE SrcList *sqlite3SrcListEnlarge(
     }
     pSrc = pNew;
     nGot = (sqlite3DbMallocSize(db, pNew) - sizeof(*pSrc))/sizeof(pSrc->a[0])+1;
-    pSrc->nAlloc = (u16)nGot;
+    pSrc->nAlloc = (u8)nGot;
   }
 
   /* Move existing slots that come after the newly inserted slots
@@ -85398,7 +85660,7 @@ SQLITE_PRIVATE SrcList *sqlite3SrcListEnlarge(
   for(i=pSrc->nSrc-1; i>=iStart; i--){
     pSrc->a[i+nExtra] = pSrc->a[i];
   }
-  pSrc->nSrc += (i16)nExtra;
+  pSrc->nSrc += (i8)nExtra;
 
   /* Zero the newly allocated slots */
   memset(&pSrc->a[iStart], 0, sizeof(pSrc->a[0])*nExtra);
@@ -85754,6 +86016,15 @@ SQLITE_PRIVATE int sqlite3OpenTempDatabase(Parse *pParse){
 SQLITE_PRIVATE void sqlite3CodeVerifySchema(Parse *pParse, int iDb){
   Parse *pToplevel = sqlite3ParseToplevel(pParse);
 
+#ifndef SQLITE_OMIT_TRIGGER
+  if( pToplevel!=pParse ){
+    /* This branch is taken if a trigger is currently being coded. In this
+    ** case, set cookieGoto to a non-zero value to show that this function
+    ** has been called. This is used by the sqlite3ExprCodeConstants()
+    ** function. */
+    pParse->cookieGoto = -1;
+  }
+#endif
   if( pToplevel->cookieGoto==0 ){
     Vdbe *v = sqlite3GetVdbe(pToplevel);
     if( v==0 ) return;  /* This only happens if there was a prior error */
@@ -85851,12 +86122,19 @@ SQLITE_PRIVATE void sqlite3MayAbort(Parse *pParse){
 ** error. The onError parameter determines which (if any) of the statement
 ** and/or current transaction is rolled back.
 */
-SQLITE_PRIVATE void sqlite3HaltConstraint(Parse *pParse, int onError, char *p4, int p4type){
+SQLITE_PRIVATE void sqlite3HaltConstraint(
+  Parse *pParse,    /* Parsing context */
+  int errCode,      /* extended error code */
+  int onError,      /* Constraint type */
+  char *p4,         /* Error message */
+  int p4type        /* P4_STATIC or P4_TRANSIENT */
+){
   Vdbe *v = sqlite3GetVdbe(pParse);
+  assert( (errCode&0xff)==SQLITE_CONSTRAINT );
   if( onError==OE_Abort ){
     sqlite3MayAbort(pParse);
   }
-  sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0, p4, p4type);
+  sqlite3VdbeAddOp4(v, OP_Halt, errCode, onError, 0, p4, p4type);
 }
 
 /*
@@ -86001,25 +86279,20 @@ SQLITE_PRIVATE void sqlite3Reindex(Parse *pParse, Token *pName1, Token *pName2){
 SQLITE_PRIVATE KeyInfo *sqlite3IndexKeyinfo(Parse *pParse, Index *pIdx){
   int i;
   int nCol = pIdx->nColumn;
-  int nBytes = sizeof(KeyInfo) + (nCol-1)*sizeof(CollSeq*) + nCol;
-  sqlite3 *db = pParse->db;
-  KeyInfo *pKey = (KeyInfo *)sqlite3DbMallocZero(db, nBytes);
+  KeyInfo *pKey;
 
+  pKey = sqlite3KeyInfoAlloc(pParse->db, nCol);
   if( pKey ){
-    pKey->db = pParse->db;
-    pKey->aSortOrder = (u8 *)&(pKey->aColl[nCol]);
-    assert( &pKey->aSortOrder[nCol]==&(((u8 *)pKey)[nBytes]) );
     for(i=0; i<nCol; i++){
       char *zColl = pIdx->azColl[i];
       assert( zColl );
       pKey->aColl[i] = sqlite3LocateCollSeq(pParse, zColl);
       pKey->aSortOrder[i] = pIdx->aSortOrder[i];
     }
-    pKey->nField = (u16)nCol;
   }
 
   if( pParse->nErr ){
-    sqlite3DbFree(db, pKey);
+    sqlite3DbFree(pParse->db, pKey);
     pKey = 0;
   }
   return pKey;
@@ -86103,17 +86376,18 @@ static int synthCollSeq(sqlite3 *db, CollSeq *pColl){
 **
 ** The return value is either the collation sequence to be used in database
 ** db for collation type name zName, length nName, or NULL, if no collation
-** sequence can be found.
+** sequence can be found.  If no collation is found, leave an error message.
 **
 ** See also: sqlite3LocateCollSeq(), sqlite3FindCollSeq()
 */
 SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(
-  sqlite3* db,          /* The database connection */
+  Parse *pParse,        /* Parsing context */
   u8 enc,               /* The desired encoding for the collating sequence */
   CollSeq *pColl,       /* Collating sequence with native encoding, or NULL */
   const char *zName     /* Collating sequence name */
 ){
   CollSeq *p;
+  sqlite3 *db = pParse->db;
 
   p = pColl;
   if( !p ){
@@ -86130,6 +86404,9 @@ SQLITE_PRIVATE CollSeq *sqlite3GetCollSeq(
     p = 0;
   }
   assert( !p || p->xCmp );
+  if( p==0 ){
+    sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
+  }
   return p;
 }
 
@@ -86148,10 +86425,8 @@ SQLITE_PRIVATE int sqlite3CheckCollSeq(Parse *pParse, CollSeq *pColl){
   if( pColl ){
     const char *zName = pColl->zName;
     sqlite3 *db = pParse->db;
-    CollSeq *p = sqlite3GetCollSeq(db, ENC(db), pColl, zName);
+    CollSeq *p = sqlite3GetCollSeq(pParse, ENC(db), pColl, zName);
     if( !p ){
-      sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
-      pParse->nErr++;
       return SQLITE_ERROR;
     }
     assert( p==pColl );
@@ -86538,7 +86813,7 @@ SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
   struct SrcList_item *pItem = pSrc->a;
   Table *pTab;
   assert( pItem && pSrc->nSrc==1 );
-  pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
+  pTab = sqlite3LocateTableItem(pParse, 0, pItem);
   sqlite3DeleteTable(pParse->db, pItem->pTab);
   pItem->pTab = pTab;
   if( pTab ){
@@ -86599,29 +86874,28 @@ SQLITE_PRIVATE void sqlite3MaterializeView(
   int iCur             /* Cursor number for ephemerial table */
 ){
   SelectDest dest;
-  Select *pDup;
+  Select *pSel;
+  SrcList *pFrom;
   sqlite3 *db = pParse->db;
+  int iDb = sqlite3SchemaToIndex(db, pView->pSchema);
 
-  pDup = sqlite3SelectDup(db, pView->pSelect, 0);
-  if( pWhere ){
-    SrcList *pFrom;
-    
-    pWhere = sqlite3ExprDup(db, pWhere, 0);
-    pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
-    if( pFrom ){
-      assert( pFrom->nSrc==1 );
-      pFrom->a[0].zAlias = sqlite3DbStrDup(db, pView->zName);
-      pFrom->a[0].pSelect = pDup;
-      assert( pFrom->a[0].pOn==0 );
-      assert( pFrom->a[0].pUsing==0 );
-    }else{
-      sqlite3SelectDelete(db, pDup);
-    }
-    pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
+  pWhere = sqlite3ExprDup(db, pWhere, 0);
+  pFrom = sqlite3SrcListAppend(db, 0, 0, 0);
+
+  if( pFrom ){
+    assert( pFrom->nSrc==1 );
+    pFrom->a[0].zName = sqlite3DbStrDup(db, pView->zName);
+    pFrom->a[0].zDatabase = sqlite3DbStrDup(db, db->aDb[iDb].zName);
+    assert( pFrom->a[0].pOn==0 );
+    assert( pFrom->a[0].pUsing==0 );
   }
+
+  pSel = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
+  if( pSel ) pSel->selFlags |= SF_Materialize;
+
   sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
-  sqlite3Select(pParse, pDup, &dest);
-  sqlite3SelectDelete(db, pDup);
+  sqlite3Select(pParse, pSel, &dest);
+  sqlite3SelectDelete(db, pSel);
 }
 #endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */
 
@@ -86877,7 +87151,7 @@ SQLITE_PRIVATE void sqlite3DeleteFrom(
     */
     sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
     pWInfo = sqlite3WhereBegin(
-        pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK
+        pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK, 0
     );
     if( pWInfo==0 ) goto delete_from_cleanup;
     regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);
@@ -87098,11 +87372,14 @@ SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(
   int i;
   Index *pIdx;
   int r1;
+  int iPartIdxLabel;
+  Vdbe *v = pParse->pVdbe;
 
   for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
     if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
-    r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
-    sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
+    r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0, &iPartIdxLabel);
+    sqlite3VdbeAddOp3(v, OP_IdxDelete, iCur+i, r1, pIdx->nColumn+1);
+    sqlite3VdbeResolveLabel(v, iPartIdxLabel);
   }
 }
 
@@ -87116,13 +87393,21 @@ SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(
 ** registers that holds the elements of the index key.  The
 ** block of registers has already been deallocated by the time
 ** this routine returns.
+**
+** If *piPartIdxLabel is not NULL, fill it in with a label and jump
+** to that label if pIdx is a partial index that should be skipped.
+** A partial index should be skipped if its WHERE clause evaluates
+** to false or null.  If pIdx is not a partial index, *piPartIdxLabel
+** will be set to zero which is an empty label that is ignored by
+** sqlite3VdbeResolveLabel().
 */
 SQLITE_PRIVATE int sqlite3GenerateIndexKey(
-  Parse *pParse,     /* Parsing context */
-  Index *pIdx,       /* The index for which to generate a key */
-  int iCur,          /* Cursor number for the pIdx->pTable table */
-  int regOut,        /* Write the new index key to this register */
-  int doMakeRec      /* Run the OP_MakeRecord instruction if true */
+  Parse *pParse,       /* Parsing context */
+  Index *pIdx,         /* The index for which to generate a key */
+  int iCur,            /* Cursor number for the pIdx->pTable table */
+  int regOut,          /* Write the new index key to this register */
+  int doMakeRec,       /* Run the OP_MakeRecord instruction if true */
+  int *piPartIdxLabel  /* OUT: Jump to this label to skip partial index */
 ){
   Vdbe *v = pParse->pVdbe;
   int j;
@@ -87130,6 +87415,16 @@ SQLITE_PRIVATE int sqlite3GenerateIndexKey(
   int regBase;
   int nCol;
 
+  if( piPartIdxLabel ){
+    if( pIdx->pPartIdxWhere ){
+      *piPartIdxLabel = sqlite3VdbeMakeLabel(v);
+      pParse->iPartIdxTab = iCur;
+      sqlite3ExprIfFalse(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel, 
+                         SQLITE_JUMPIFNULL);
+    }else{
+      *piPartIdxLabel = 0;
+    }
+  }
   nCol = pIdx->nColumn;
   regBase = sqlite3GetTempRange(pParse, nCol+1);
   sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
@@ -87144,7 +87439,9 @@ SQLITE_PRIVATE int sqlite3GenerateIndexKey(
   }
   if( doMakeRec ){
     const char *zAff;
-    if( pTab->pSelect || (pParse->db->flags & SQLITE_IdxRealAsInt)!=0 ){
+    if( pTab->pSelect
+     || OptimizationDisabled(pParse->db, SQLITE_IdxRealAsInt)
+    ){
       zAff = 0;
     }else{
       zAff = sqlite3IndexAffinityStr(v, pIdx);
@@ -87326,6 +87623,56 @@ static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   }
 }
 
+/*
+** Implementation of the instr() function.
+**
+** instr(haystack,needle) finds the first occurrence of needle
+** in haystack and returns the number of previous characters plus 1,
+** or 0 if needle does not occur within haystack.
+**
+** If both haystack and needle are BLOBs, then the result is one more than
+** the number of bytes in haystack prior to the first occurrence of needle,
+** or 0 if needle never occurs in haystack.
+*/
+static void instrFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  const unsigned char *zHaystack;
+  const unsigned char *zNeedle;
+  int nHaystack;
+  int nNeedle;
+  int typeHaystack, typeNeedle;
+  int N = 1;
+  int isText;
+
+  UNUSED_PARAMETER(argc);
+  typeHaystack = sqlite3_value_type(argv[0]);
+  typeNeedle = sqlite3_value_type(argv[1]);
+  if( typeHaystack==SQLITE_NULL || typeNeedle==SQLITE_NULL ) return;
+  nHaystack = sqlite3_value_bytes(argv[0]);
+  nNeedle = sqlite3_value_bytes(argv[1]);
+  if( typeHaystack==SQLITE_BLOB && typeNeedle==SQLITE_BLOB ){
+    zHaystack = sqlite3_value_blob(argv[0]);
+    zNeedle = sqlite3_value_blob(argv[1]);
+    isText = 0;
+  }else{
+    zHaystack = sqlite3_value_text(argv[0]);
+    zNeedle = sqlite3_value_text(argv[1]);
+    isText = 1;
+  }
+  while( nNeedle<=nHaystack && memcmp(zHaystack, zNeedle, nNeedle)!=0 ){
+    N++;
+    do{
+      nHaystack--;
+      zHaystack++;
+    }while( isText && (zHaystack[0]&0xc0)==0x80 );
+  }
+  if( nNeedle>nHaystack ) N = 0;
+  sqlite3_result_int(context, N);
+}
+
 /*
 ** Implementation of the substr() function.
 **
@@ -87336,7 +87683,7 @@ static void absFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
 **
 ** If p1 is negative, then we begin abs(p1) from the end of x[].
 **
-** If p2 is negative, return the p2 characters preceeding p1.
+** If p2 is negative, return the p2 characters preceding p1.
 */
 static void substrFunc(
   sqlite3_context *context,
@@ -87525,33 +87872,14 @@ static void lowerFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   }
 }
 
-
-#if 0  /* This function is never used. */
 /*
-** The COALESCE() and IFNULL() functions used to be implemented as shown
-** here.  But now they are implemented as VDBE code so that unused arguments
-** do not have to be computed.  This legacy implementation is retained as
-** comment.
+** The COALESCE() and IFNULL() functions are implemented as VDBE code so
+** that unused argument values do not have to be computed.  However, we
+** still need some kind of function implementation for this routines in
+** the function table.  That function implementation will never be called
+** so it doesn't matter what the implementation is.  We might as well use
+** the "version()" function as a substitute.
 */
-/*
-** Implementation of the IFNULL(), NVL(), and COALESCE() functions.  
-** All three do the same thing.  They return the first non-NULL
-** argument.
-*/
-static void ifnullFunc(
-  sqlite3_context *context,
-  int argc,
-  sqlite3_value **argv
-){
-  int i;
-  for(i=0; i<argc; i++){
-    if( SQLITE_NULL!=sqlite3_value_type(argv[i]) ){
-      sqlite3_result_value(context, argv[i]);
-      break;
-    }
-  }
-}
-#endif /* NOT USED */
 #define ifnullFunc versionFunc   /* Substitute function - never called */
 
 /*
@@ -87670,7 +87998,7 @@ struct compareInfo {
 ** whereas only characters less than 0x80 do in ASCII.
 */
 #if defined(SQLITE_EBCDIC)
-# define sqlite3Utf8Read(A,C)  (*(A++))
+# define sqlite3Utf8Read(A)    (*((*A)++))
 # define GlogUpperToLower(A)   A = sqlite3UpperToLower[A]
 #else
 # define GlogUpperToLower(A)   if( !((A)&~0x7f) ){ A = sqlite3UpperToLower[A]; }
@@ -87727,18 +88055,18 @@ static int patternCompare(
   u8 noCase = pInfo->noCase; 
   int prevEscape = 0;     /* True if the previous character was 'escape' */
 
-  while( (c = sqlite3Utf8Read(zPattern,&zPattern))!=0 ){
-    if( !prevEscape && c==matchAll ){
-      while( (c=sqlite3Utf8Read(zPattern,&zPattern)) == matchAll
+  while( (c = sqlite3Utf8Read(&zPattern))!=0 ){
+    if( c==matchAll && !prevEscape ){
+      while( (c=sqlite3Utf8Read(&zPattern)) == matchAll
                || c == matchOne ){
-        if( c==matchOne && sqlite3Utf8Read(zString, &zString)==0 ){
+        if( c==matchOne && sqlite3Utf8Read(&zString)==0 ){
           return 0;
         }
       }
       if( c==0 ){
         return 1;
       }else if( c==esc ){
-        c = sqlite3Utf8Read(zPattern, &zPattern);
+        c = sqlite3Utf8Read(&zPattern);
         if( c==0 ){
           return 0;
         }
@@ -87750,25 +88078,25 @@ static int patternCompare(
         }
         return *zString!=0;
       }
-      while( (c2 = sqlite3Utf8Read(zString,&zString))!=0 ){
+      while( (c2 = sqlite3Utf8Read(&zString))!=0 ){
         if( noCase ){
           GlogUpperToLower(c2);
           GlogUpperToLower(c);
           while( c2 != 0 && c2 != c ){
-            c2 = sqlite3Utf8Read(zString, &zString);
+            c2 = sqlite3Utf8Read(&zString);
             GlogUpperToLower(c2);
           }
         }else{
           while( c2 != 0 && c2 != c ){
-            c2 = sqlite3Utf8Read(zString, &zString);
+            c2 = sqlite3Utf8Read(&zString);
           }
         }
         if( c2==0 ) return 0;
         if( patternCompare(zPattern,zString,pInfo,esc) ) return 1;
       }
       return 0;
-    }else if( !prevEscape && c==matchOne ){
-      if( sqlite3Utf8Read(zString, &zString)==0 ){
+    }else if( c==matchOne && !prevEscape ){
+      if( sqlite3Utf8Read(&zString)==0 ){
         return 0;
       }
     }else if( c==matchSet ){
@@ -87776,20 +88104,20 @@ static int patternCompare(
       assert( esc==0 );    /* This only occurs for GLOB, not LIKE */
       seen = 0;
       invert = 0;
-      c = sqlite3Utf8Read(zString, &zString);
+      c = sqlite3Utf8Read(&zString);
       if( c==0 ) return 0;
-      c2 = sqlite3Utf8Read(zPattern, &zPattern);
+      c2 = sqlite3Utf8Read(&zPattern);
       if( c2=='^' ){
         invert = 1;
-        c2 = sqlite3Utf8Read(zPattern, &zPattern);
+        c2 = sqlite3Utf8Read(&zPattern);
       }
       if( c2==']' ){
         if( c==']' ) seen = 1;
-        c2 = sqlite3Utf8Read(zPattern, &zPattern);
+        c2 = sqlite3Utf8Read(&zPattern);
       }
       while( c2 && c2!=']' ){
         if( c2=='-' && zPattern[0]!=']' && zPattern[0]!=0 && prior_c>0 ){
-          c2 = sqlite3Utf8Read(zPattern, &zPattern);
+          c2 = sqlite3Utf8Read(&zPattern);
           if( c>=prior_c && c<=c2 ) seen = 1;
           prior_c = 0;
         }else{
@@ -87798,7 +88126,7 @@ static int patternCompare(
           }
           prior_c = c2;
         }
-        c2 = sqlite3Utf8Read(zPattern, &zPattern);
+        c2 = sqlite3Utf8Read(&zPattern);
       }
       if( c2==0 || (seen ^ invert)==0 ){
         return 0;
@@ -87806,7 +88134,7 @@ static int patternCompare(
     }else if( esc==c && !prevEscape ){
       prevEscape = 1;
     }else{
-      c2 = sqlite3Utf8Read(zString, &zString);
+      c2 = sqlite3Utf8Read(&zString);
       if( noCase ){
         GlogUpperToLower(c);
         GlogUpperToLower(c2);
@@ -87820,6 +88148,13 @@ static int patternCompare(
   return *zString==0;
 }
 
+/*
+** The sqlite3_strglob() interface.
+*/
+SQLITE_API int sqlite3_strglob(const char *zGlobPattern, const char *zString){
+  return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, 0)==0;
+}
+
 /*
 ** Count the number of times that the LIKE operator (or GLOB which is
 ** just a variation of LIKE) gets called.  This is used for testing
@@ -87878,7 +88213,7 @@ static void likeFunc(
           "ESCAPE expression must be a single character", -1);
       return;
     }
-    escape = sqlite3Utf8Read(zEsc, &zEsc);
+    escape = sqlite3Utf8Read(&zEsc);
   }
   if( zA && zB ){
     struct compareInfo *pInfo = sqlite3_user_data(context);
@@ -88007,10 +88342,6 @@ static const char hexdigits[] = {
 };
 
 /*
-** EXPERIMENTAL - This is not an official function.  The interface may
-** change.  This function may disappear.  Do not write code that depends
-** on this function.
-**
 ** Implementation of the QUOTE() function.  This function takes a single
 ** argument.  If the argument is numeric, the return value is the same as
 ** the argument.  If the argument is NULL, the return value is the string
@@ -88021,8 +88352,19 @@ static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   assert( argc==1 );
   UNUSED_PARAMETER(argc);
   switch( sqlite3_value_type(argv[0]) ){
-    case SQLITE_INTEGER:
     case SQLITE_FLOAT: {
+      double r1, r2;
+      char zBuf[50];
+      r1 = sqlite3_value_double(argv[0]);
+      sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.15g", r1);
+      sqlite3AtoF(zBuf, &r2, 20, SQLITE_UTF8);
+      if( r1!=r2 ){
+        sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.20e", r1);
+      }
+      sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
+      break;
+    }
+    case SQLITE_INTEGER: {
       sqlite3_result_value(context, argv[0]);
       break;
     }
@@ -88078,6 +88420,62 @@ static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   }
 }
 
+/*
+** The unicode() function.  Return the integer unicode code-point value
+** for the first character of the input string. 
+*/
+static void unicodeFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  const unsigned char *z = sqlite3_value_text(argv[0]);
+  (void)argc;
+  if( z && z[0] ) sqlite3_result_int(context, sqlite3Utf8Read(&z));
+}
+
+/*
+** The char() function takes zero or more arguments, each of which is
+** an integer.  It constructs a string where each character of the string
+** is the unicode character for the corresponding integer argument.
+*/
+static void charFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  unsigned char *z, *zOut;
+  int i;
+  zOut = z = sqlite3_malloc( argc*4 );
+  if( z==0 ){
+    sqlite3_result_error_nomem(context);
+    return;
+  }
+  for(i=0; i<argc; i++){
+    sqlite3_int64 x;
+    unsigned c;
+    x = sqlite3_value_int64(argv[i]);
+    if( x<0 || x>0x10ffff ) x = 0xfffd;
+    c = (unsigned)(x & 0x1fffff);
+    if( c<0x00080 ){
+      *zOut++ = (u8)(c&0xFF);
+    }else if( c<0x00800 ){
+      *zOut++ = 0xC0 + (u8)((c>>6)&0x1F);
+      *zOut++ = 0x80 + (u8)(c & 0x3F);
+    }else if( c<0x10000 ){
+      *zOut++ = 0xE0 + (u8)((c>>12)&0x0F);
+      *zOut++ = 0x80 + (u8)((c>>6) & 0x3F);
+      *zOut++ = 0x80 + (u8)(c & 0x3F);
+    }else{
+      *zOut++ = 0xF0 + (u8)((c>>18) & 0x07);
+      *zOut++ = 0x80 + (u8)((c>>12) & 0x3F);
+      *zOut++ = 0x80 + (u8)((c>>6) & 0x3F);
+      *zOut++ = 0x80 + (u8)(c & 0x3F);
+    }                                                    \
+  }
+  sqlite3_result_text(context, (char*)z, (int)(zOut-z), sqlite3_free);
+}
+
 /*
 ** The hex() function.  Interpret the argument as a blob.  Return
 ** a hexadecimal rendering as text.
@@ -88132,7 +88530,7 @@ static void zeroblobFunc(
 /*
 ** The replace() function.  Three arguments are all strings: call
 ** them A, B, and C. The result is also a string which is derived
-** from A by replacing every occurance of B with C.  The match
+** from A by replacing every occurrence of B with C.  The match
 ** must be exact.  Collating sequences are not used.
 */
 static void replaceFunc(
@@ -88579,9 +88977,9 @@ static void groupConcatFinalize(sqlite3_context *context){
   StrAccum *pAccum;
   pAccum = sqlite3_aggregate_context(context, 0);
   if( pAccum ){
-    if( pAccum->tooBig ){
+    if( pAccum->accError==STRACCUM_TOOBIG ){
       sqlite3_result_error_toobig(context);
-    }else if( pAccum->mallocFailed ){
+    }else if( pAccum->accError==STRACCUM_NOMEM ){
       sqlite3_result_error_nomem(context);
     }else{    
       sqlite3_result_text(context, sqlite3StrAccumFinish(pAccum), -1, 
@@ -88702,8 +89100,11 @@ SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void){
     AGGREGATE(max,               1, 1, 1, minmaxStep,      minMaxFinalize ),
     FUNCTION2(typeof,            1, 0, 0, typeofFunc,  SQLITE_FUNC_TYPEOF),
     FUNCTION2(length,            1, 0, 0, lengthFunc,  SQLITE_FUNC_LENGTH),
+    FUNCTION(instr,              2, 0, 0, instrFunc        ),
     FUNCTION(substr,             2, 0, 0, substrFunc       ),
     FUNCTION(substr,             3, 0, 0, substrFunc       ),
+    FUNCTION(unicode,            1, 0, 0, unicodeFunc      ),
+    FUNCTION(char,              -1, 0, 0, charFunc         ),
     FUNCTION(abs,                1, 0, 0, absFunc          ),
 #ifndef SQLITE_OMIT_FLOATING_POINT
     FUNCTION(round,              1, 0, 0, roundFunc        ),
@@ -88795,8 +89196,9 @@ SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void){
 ** --------------------------
 **
 ** Foreign keys in SQLite come in two flavours: deferred and immediate.
-** If an immediate foreign key constraint is violated, SQLITE_CONSTRAINT
-** is returned and the current statement transaction rolled back. If a 
+** If an immediate foreign key constraint is violated,
+** SQLITE_CONSTRAINT_FOREIGNKEY is returned and the current
+** statement transaction rolled back. If a 
 ** deferred foreign key constraint is violated, no action is taken 
 ** immediately. However if the application attempts to commit the 
 ** transaction before fixing the constraint violation, the attempt fails.
@@ -88860,7 +89262,8 @@ SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void){
 ** Immediate constraints are usually handled similarly. The only difference 
 ** is that the counter used is stored as part of each individual statement
 ** object (struct Vdbe). If, after the statement has run, its immediate
-** constraint counter is greater than zero, it returns SQLITE_CONSTRAINT
+** constraint counter is greater than zero,
+** it returns SQLITE_CONSTRAINT_FOREIGNKEY
 ** and the statement transaction is rolled back. An exception is an INSERT
 ** statement that inserts a single row only (no triggers). In this case,
 ** instead of using a counter, an exception is thrown immediately if the
@@ -88916,7 +89319,7 @@ SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void){
 ** A foreign key constraint requires that the key columns in the parent
 ** table are collectively subject to a UNIQUE or PRIMARY KEY constraint.
 ** Given that pParent is the parent table for foreign key constraint pFKey, 
-** search the schema a unique index on the parent key columns. 
+** search the schema for a unique index on the parent key columns. 
 **
 ** If successful, zero is returned. If the parent key is an INTEGER PRIMARY 
 ** KEY column, then output variable *ppIdx is set to NULL. Otherwise, *ppIdx 
@@ -88952,7 +89355,7 @@ SQLITE_PRIVATE void sqlite3RegisterGlobalFunctions(void){
 ** into pParse. If an OOM error occurs, non-zero is returned and the
 ** pParse->db->mallocFailed flag is set.
 */
-static int locateFkeyIndex(
+SQLITE_PRIVATE int sqlite3FkLocateIndex(
   Parse *pParse,                  /* Parse context to store any error in */
   Table *pParent,                 /* Parent table of FK constraint pFKey */
   FKey *pFKey,                    /* Foreign key to find index for */
@@ -89049,7 +89452,9 @@ static int locateFkeyIndex(
 
   if( !pIdx ){
     if( !pParse->disableTriggers ){
-      sqlite3ErrorMsg(pParse, "foreign key mismatch");
+      sqlite3ErrorMsg(pParse,
+           "foreign key mismatch - \"%w\" referencing \"%w\"",
+           pFKey->pFrom->zName, pFKey->zTo);
     }
     sqlite3DbFree(pParse->db, aiCol);
     return 1;
@@ -89192,14 +89597,17 @@ static void fkLookupParent(
     }
   }
 
-  if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){
+  if( !pFKey->isDeferred && !(pParse->db->flags & SQLITE_DeferFKs)
+   && !pParse->pToplevel 
+   && !pParse->isMultiWrite 
+  ){
     /* Special case: If this is an INSERT statement that will insert exactly
     ** one row into the table, raise a constraint immediately instead of
     ** incrementing a counter. This is necessary as the VM code is being
     ** generated for will not open a statement transaction.  */
     assert( nIncr==1 );
-    sqlite3HaltConstraint(
-        pParse, OE_Abort, "foreign key constraint failed", P4_STATIC
+    sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_FOREIGNKEY,
+        OE_Abort, "foreign key constraint failed", P4_STATIC
     );
   }else{
     if( nIncr>0 && pFKey->isDeferred==0 ){
@@ -89285,12 +89693,15 @@ static void fkScanChildren(
       ** expression to the parent key column defaults.  */
       if( pIdx ){
         Column *pCol;
+        const char *zColl;
         iCol = pIdx->aiColumn[i];
         pCol = &pTab->aCol[iCol];
         if( pTab->iPKey==iCol ) iCol = -1;
         pLeft->iTable = regData+iCol+1;
         pLeft->affinity = pCol->affinity;
-        pLeft->pColl = sqlite3LocateCollSeq(pParse, pCol->zColl);
+        zColl = pCol->zColl;
+        if( zColl==0 ) zColl = db->pDfltColl->zName;
+        pLeft = sqlite3ExprAddCollateString(pParse, pLeft, zColl);
       }else{
         pLeft->iTable = regData;
         pLeft->affinity = SQLITE_AFF_INTEGER;
@@ -89334,7 +89745,7 @@ static void fkScanChildren(
   ** clause. If the constraint is not deferred, throw an exception for
   ** each row found. Otherwise, for deferred constraints, increment the
   ** deferred constraint counter by nIncr for each row selected.  */
-  pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0, 0);
+  pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0, 0, 0);
   if( nIncr>0 && pFKey->isDeferred==0 ){
     sqlite3ParseToplevel(pParse)->mayAbort = 1;
   }
@@ -89436,8 +89847,8 @@ SQLITE_PRIVATE void sqlite3FkDropTable(Parse *pParse, SrcList *pName, Table *pTa
     ** any modifications to the schema are made. This is because statement
     ** transactions are not able to rollback schema changes.  */
     sqlite3VdbeAddOp2(v, OP_FkIfZero, 0, sqlite3VdbeCurrentAddr(v)+2);
-    sqlite3HaltConstraint(
-        pParse, OE_Abort, "foreign key constraint failed", P4_STATIC
+    sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_FOREIGNKEY,
+        OE_Abort, "foreign key constraint failed", P4_STATIC
     );
 
     if( iSkip ){
@@ -89507,7 +89918,7 @@ SQLITE_PRIVATE void sqlite3FkCheck(
     }else{
       pTo = sqlite3LocateTable(pParse, 0, pFKey->zTo, zDb);
     }
-    if( !pTo || locateFkeyIndex(pParse, pTo, pFKey, &pIdx, &aiFree) ){
+    if( !pTo || sqlite3FkLocateIndex(pParse, pTo, pFKey, &pIdx, &aiFree) ){
       assert( isIgnoreErrors==0 || (regOld!=0 && regNew==0) );
       if( !isIgnoreErrors || db->mallocFailed ) return;
       if( pTo==0 ){
@@ -89580,14 +89991,16 @@ SQLITE_PRIVATE void sqlite3FkCheck(
     SrcList *pSrc;
     int *aiCol = 0;
 
-    if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){
+    if( !pFKey->isDeferred && !(db->flags & SQLITE_DeferFKs) 
+     && !pParse->pToplevel && !pParse->isMultiWrite 
+    ){
       assert( regOld==0 && regNew!=0 );
       /* Inserting a single row into a parent table cannot cause an immediate
       ** foreign key violation. So do nothing in this case.  */
       continue;
     }
 
-    if( locateFkeyIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ){
+    if( sqlite3FkLocateIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ){
       if( !isIgnoreErrors || db->mallocFailed ) return;
       continue;
     }
@@ -89642,7 +90055,7 @@ SQLITE_PRIVATE u32 sqlite3FkOldmask(
     }
     for(p=sqlite3FkReferences(pTab); p; p=p->pNextTo){
       Index *pIdx = 0;
-      locateFkeyIndex(pParse, pTab, p, &pIdx, 0);
+      sqlite3FkLocateIndex(pParse, pTab, p, &pIdx, 0);
       if( pIdx ){
         for(i=0; i<pIdx->nColumn; i++) mask |= COLUMN_MASK(pIdx->aiColumn[i]);
       }
@@ -89699,7 +90112,8 @@ SQLITE_PRIVATE int sqlite3FkRequired(
           int iKey;
           for(iKey=0; iKey<pTab->nCol; iKey++){
             Column *pCol = &pTab->aCol[iKey];
-            if( (zKey ? !sqlite3StrICmp(pCol->zName, zKey) : pCol->isPrimKey) ){
+            if( (zKey ? !sqlite3StrICmp(pCol->zName, zKey)
+                      : (pCol->colFlags & COLFLAG_PRIMKEY)!=0) ){
               if( aChange[iKey]>=0 ) return 1;
               if( iKey==pTab->iPKey && chngRowid ) return 1;
             }
@@ -89767,7 +90181,7 @@ static Trigger *fkActionTrigger(
     int i;                        /* Iterator variable */
     Expr *pWhen = 0;              /* WHEN clause for the trigger */
 
-    if( locateFkeyIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ) return 0;
+    if( sqlite3FkLocateIndex(pParse, pTab, pFKey, &pIdx, &aiCol) ) return 0;
     assert( aiCol || pFKey->nCol==1 );
 
     for(i=0; i<pFKey->nCol; i++){
@@ -90020,7 +90434,7 @@ SQLITE_PRIVATE void sqlite3OpenTable(
   int opcode      /* OP_OpenRead or OP_OpenWrite */
 ){
   Vdbe *v;
-  if( IsVirtual(pTab) ) return;
+  assert( !IsVirtual(pTab) );
   v = sqlite3GetVdbe(p);
   assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
   sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite)?1:0, pTab->zName);
@@ -90315,6 +90729,97 @@ SQLITE_PRIVATE void sqlite3AutoincrementEnd(Parse *pParse){
 #endif /* SQLITE_OMIT_AUTOINCREMENT */
 
 
+/*
+** Generate code for a co-routine that will evaluate a subquery one
+** row at a time.
+**
+** The pSelect parameter is the subquery that the co-routine will evaluation.
+** Information about the location of co-routine and the registers it will use
+** is returned by filling in the pDest object.
+**
+** Registers are allocated as follows:
+**
+**   pDest->iSDParm      The register holding the next entry-point of the
+**                       co-routine.  Run the co-routine to its next breakpoint
+**                       by calling "OP_Yield $X" where $X is pDest->iSDParm.
+**
+**   pDest->iSDParm+1    The register holding the "completed" flag for the
+**                       co-routine. This register is 0 if the previous Yield
+**                       generated a new result row, or 1 if the subquery
+**                       has completed.  If the Yield is called again
+**                       after this register becomes 1, then the VDBE will
+**                       halt with an SQLITE_INTERNAL error.
+**
+**   pDest->iSdst        First result register.
+**
+**   pDest->nSdst        Number of result registers.
+**
+** This routine handles all of the register allocation and fills in the
+** pDest structure appropriately.
+**
+** Here is a schematic of the generated code assuming that X is the 
+** co-routine entry-point register reg[pDest->iSDParm], that EOF is the
+** completed flag reg[pDest->iSDParm+1], and R and S are the range of
+** registers that hold the result set, reg[pDest->iSdst] through
+** reg[pDest->iSdst+pDest->nSdst-1]:
+**
+**         X <- A
+**         EOF <- 0
+**         goto B
+**      A: setup for the SELECT
+**         loop rows in the SELECT
+**           load results into registers R..S
+**           yield X
+**         end loop
+**         cleanup after the SELECT
+**         EOF <- 1
+**         yield X
+**         halt-error
+**      B:
+**
+** To use this subroutine, the caller generates code as follows:
+**
+**         [ Co-routine generated by this subroutine, shown above ]
+**      S: yield X
+**         if EOF goto E
+**         if skip this row, goto C
+**         if terminate loop, goto E
+**         deal with this row
+**      C: goto S
+**      E:
+*/
+SQLITE_PRIVATE int sqlite3CodeCoroutine(Parse *pParse, Select *pSelect, SelectDest *pDest){
+  int regYield;       /* Register holding co-routine entry-point */
+  int regEof;         /* Register holding co-routine completion flag */
+  int addrTop;        /* Top of the co-routine */
+  int j1;             /* Jump instruction */
+  int rc;             /* Result code */
+  Vdbe *v;            /* VDBE under construction */
+
+  regYield = ++pParse->nMem;
+  regEof = ++pParse->nMem;
+  v = sqlite3GetVdbe(pParse);
+  addrTop = sqlite3VdbeCurrentAddr(v);
+  sqlite3VdbeAddOp2(v, OP_Integer, addrTop+2, regYield); /* X <- A */
+  VdbeComment((v, "Co-routine entry point"));
+  sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof);           /* EOF <- 0 */
+  VdbeComment((v, "Co-routine completion flag"));
+  sqlite3SelectDestInit(pDest, SRT_Coroutine, regYield);
+  j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
+  rc = sqlite3Select(pParse, pSelect, pDest);
+  assert( pParse->nErr==0 || rc );
+  if( pParse->db->mallocFailed && rc==SQLITE_OK ) rc = SQLITE_NOMEM;
+  if( rc ) return rc;
+  sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof);            /* EOF <- 1 */
+  sqlite3VdbeAddOp1(v, OP_Yield, regYield);   /* yield X */
+  sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
+  VdbeComment((v, "End of coroutine"));
+  sqlite3VdbeJumpHere(v, j1);                             /* label B: */
+  return rc;
+}
+
+
+
 /* Forward declaration */
 static int xferOptimization(
   Parse *pParse,        /* Parser context */
@@ -90563,55 +91068,16 @@ SQLITE_PRIVATE void sqlite3Insert(
   ** co-routine is the common header to the 3rd and 4th templates.
   */
   if( pSelect ){
-    /* Data is coming from a SELECT.  Generate code to implement that SELECT
-    ** as a co-routine.  The code is common to both the 3rd and 4th
-    ** templates:
-    **
-    **         EOF <- 0
-    **         X <- A
-    **         goto B
-    **      A: setup for the SELECT
-    **         loop over the tables in the SELECT
-    **           load value into register R..R+n
-    **           yield X
-    **         end loop
-    **         cleanup after the SELECT
-    **         EOF <- 1
-    **         yield X
-    **         halt-error
-    **
-    ** On each invocation of the co-routine, it puts a single row of the
-    ** SELECT result into registers dest.iMem...dest.iMem+dest.nMem-1.
-    ** (These output registers are allocated by sqlite3Select().)  When
-    ** the SELECT completes, it sets the EOF flag stored in regEof.
-    */
-    int rc, j1;
+    /* Data is coming from a SELECT.  Generate a co-routine to run that
+    ** SELECT. */
+    int rc = sqlite3CodeCoroutine(pParse, pSelect, &dest);
+    if( rc ) goto insert_cleanup;
 
-    regEof = ++pParse->nMem;
-    sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof);      /* EOF <- 0 */
-    VdbeComment((v, "SELECT eof flag"));
-    sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem);
-    addrSelect = sqlite3VdbeCurrentAddr(v)+2;
-    sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iParm);
-    j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
-    VdbeComment((v, "Jump over SELECT coroutine"));
-
-    /* Resolve the expressions in the SELECT statement and execute it. */
-    rc = sqlite3Select(pParse, pSelect, &dest);
-    assert( pParse->nErr==0 || rc );
-    if( rc || NEVER(pParse->nErr) || db->mallocFailed ){
-      goto insert_cleanup;
-    }
-    sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof);         /* EOF <- 1 */
-    sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);   /* yield X */
-    sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
-    VdbeComment((v, "End of SELECT coroutine"));
-    sqlite3VdbeJumpHere(v, j1);                          /* label B: */
-
-    regFromSelect = dest.iMem;
+    regEof = dest.iSDParm + 1;
+    regFromSelect = dest.iSdst;
     assert( pSelect->pEList );
     nColumn = pSelect->pEList->nExpr;
-    assert( dest.nMem==nColumn );
+    assert( dest.nSdst==nColumn );
 
     /* Set useTempTable to TRUE if the result of the SELECT statement
     ** should be written into a temporary table (template 4).  Set to
@@ -90647,7 +91113,7 @@ SQLITE_PRIVATE void sqlite3Insert(
       regRec = sqlite3GetTempReg(pParse);
       regTempRowid = sqlite3GetTempReg(pParse);
       sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
-      addrTop = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
+      addrTop = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm);
       addrIf = sqlite3VdbeAddOp1(v, OP_If, regEof);
       sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
       sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid);
@@ -90784,7 +91250,7 @@ SQLITE_PRIVATE void sqlite3Insert(
     **         goto C
     **      D: ...
     */
-    addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
+    addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm);
     addrInsTop = sqlite3VdbeAddOp1(v, OP_If, regEof);
   }
 
@@ -91188,7 +91654,7 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
       case OE_Fail: {
         char *zMsg;
         sqlite3VdbeAddOp3(v, OP_HaltIfNull,
-                                  SQLITE_CONSTRAINT, onError, regData+i);
+                          SQLITE_CONSTRAINT_NOTNULL, onError, regData+i);
         zMsg = sqlite3MPrintf(db, "%s.%s may not be NULL",
                               pTab->zName, pTab->aCol[i].zName);
         sqlite3VdbeChangeP4(v, -1, zMsg, P4_DYNAMIC);
@@ -91228,7 +91694,8 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
         }else{
           zConsName = 0;
         }
-        sqlite3HaltConstraint(pParse, onError, zConsName, P4_DYNAMIC);
+        sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_CHECK,
+                              onError, zConsName, P4_DYNAMIC);
       }
       sqlite3VdbeResolveLabel(v, allOk);
     }
@@ -91259,14 +91726,14 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
       case OE_Rollback:
       case OE_Abort:
       case OE_Fail: {
-        sqlite3HaltConstraint(
-          pParse, onError, "PRIMARY KEY must be unique", P4_STATIC);
+        sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_PRIMARYKEY,
+           onError, "PRIMARY KEY must be unique", P4_STATIC);
         break;
       }
       case OE_Replace: {
         /* If there are DELETE triggers on this table and the
         ** recursive-triggers flag is set, call GenerateRowDelete() to
-        ** remove the conflicting row from the the table. This will fire
+        ** remove the conflicting row from the table. This will fire
         ** the triggers and remove both the table and index b-tree entries.
         **
         ** Otherwise, if there are no triggers or the recursive-triggers
@@ -91321,9 +91788,19 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
   for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){
     int regIdx;
     int regR;
+    int addrSkipRow = 0;
 
     if( aRegIdx[iCur]==0 ) continue;  /* Skip unused indices */
 
+    if( pIdx->pPartIdxWhere ){
+      sqlite3VdbeAddOp2(v, OP_Null, 0, aRegIdx[iCur]);
+      addrSkipRow = sqlite3VdbeMakeLabel(v);
+      pParse->ckBase = regData;
+      sqlite3ExprIfFalse(pParse, pIdx->pPartIdxWhere, addrSkipRow,
+                         SQLITE_JUMPIFNULL);
+      pParse->ckBase = 0;
+    }
+
     /* Create a key for accessing the index entry */
     regIdx = sqlite3GetTempRange(pParse, pIdx->nColumn+1);
     for(i=0; i<pIdx->nColumn; i++){
@@ -91343,6 +91820,7 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
     onError = pIdx->onError;
     if( onError==OE_None ){ 
       sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1);
+      sqlite3VdbeResolveLabel(v, addrSkipRow);
       continue;  /* pIdx is not a UNIQUE index */
     }
     if( overrideError!=OE_Default ){
@@ -91387,7 +91865,8 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
         sqlite3StrAccumAppend(&errMsg,
             pIdx->nColumn>1 ? " are not unique" : " is not unique", -1);
         zErr = sqlite3StrAccumFinish(&errMsg);
-        sqlite3HaltConstraint(pParse, onError, zErr, 0);
+        sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_UNIQUE,
+                              onError, zErr, 0);
         sqlite3DbFree(errMsg.db, zErr);
         break;
       }
@@ -91411,6 +91890,7 @@ SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
       }
     }
     sqlite3VdbeJumpHere(v, j3);
+    sqlite3VdbeResolveLabel(v, addrSkipRow);
     sqlite3ReleaseTempReg(pParse, regR);
   }
   
@@ -91440,7 +91920,6 @@ SQLITE_PRIVATE void sqlite3CompleteInsertion(
 ){
   int i;
   Vdbe *v;
-  int nIdx;
   Index *pIdx;
   u8 pik_flags;
   int regData;
@@ -91449,9 +91928,11 @@ SQLITE_PRIVATE void sqlite3CompleteInsertion(
   v = sqlite3GetVdbe(pParse);
   assert( v!=0 );
   assert( pTab->pSelect==0 );  /* This table is not a VIEW */
-  for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
-  for(i=nIdx-1; i>=0; i--){
+  for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
     if( aRegIdx[i]==0 ) continue;
+    if( pIdx->pPartIdxWhere ){
+      sqlite3VdbeAddOp2(v, OP_IsNull, aRegIdx[i], sqlite3VdbeCurrentAddr(v)+2);
+    }
     sqlite3VdbeAddOp2(v, OP_IdxInsert, baseCur+i+1, aRegIdx[i]);
     if( useSeekResult ){
       sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
@@ -91553,6 +92034,7 @@ static int xferCompatibleCollation(const char *z1, const char *z2){
 **    *   The same DESC and ASC markings occurs on all columns
 **    *   The same onError processing (OE_Abort, OE_Ignore, etc)
 **    *   The same collating sequence on each column
+**    *   The index has the exact same WHERE clause
 */
 static int xferCompatibleIndex(Index *pDest, Index *pSrc){
   int i;
@@ -91575,6 +92057,9 @@ static int xferCompatibleIndex(Index *pDest, Index *pSrc){
       return 0;   /* Different collating sequences */
     }
   }
+  if( sqlite3ExprCompare(pSrc->pPartIdxWhere, pDest->pPartIdxWhere, -1) ){
+    return 0;     /* Different WHERE clauses */
+  }
 
   /* If no test above fails then the indices must be compatible */
   return 1;
@@ -91686,7 +92171,7 @@ static int xferOptimization(
   ** we have to check the semantics.
   */
   pItem = pSelect->pSrc->a;
-  pSrc = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
+  pSrc = sqlite3LocateTableItem(pParse, 0, pItem);
   if( pSrc==0 ){
     return 0;   /* FROM clause does not contain a real table */
   }
@@ -91730,7 +92215,7 @@ static int xferOptimization(
     }
   }
 #ifndef SQLITE_OMIT_CHECK
-  if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck, pDest->pCheck) ){
+  if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck,pDest->pCheck,-1) ){
     return 0;   /* Tables have different CHECK constraints.  Ticket #2252 */
   }
 #endif
@@ -91795,8 +92280,8 @@ static int xferOptimization(
   if( pDest->iPKey>=0 ){
     addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid);
     addr2 = sqlite3VdbeAddOp3(v, OP_NotExists, iDest, 0, regRowid);
-    sqlite3HaltConstraint(
-        pParse, onError, "PRIMARY KEY must be unique", P4_STATIC);
+    sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_PRIMARYKEY,
+        onError, "PRIMARY KEY must be unique", P4_STATIC);
     sqlite3VdbeJumpHere(v, addr2);
     autoIncStep(pParse, regAutoinc, regRowid);
   }else if( pDest->pIndex==0 ){
@@ -91888,7 +92373,6 @@ SQLITE_API int sqlite3_exec(
   const char *zLeftover;      /* Tail of unprocessed SQL */
   sqlite3_stmt *pStmt = 0;    /* The current SQL statement */
   char **azCols = 0;          /* Names of result columns */
-  int nRetry = 0;             /* Number of retry attempts */
   int callbackIsInit;         /* True if callback data is initialized */
 
   if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
@@ -91896,12 +92380,12 @@ SQLITE_API int sqlite3_exec(
 
   sqlite3_mutex_enter(db->mutex);
   sqlite3Error(db, SQLITE_OK, 0);
-  while( (rc==SQLITE_OK || (rc==SQLITE_SCHEMA && (++nRetry)<2)) && zSql[0] ){
+  while( rc==SQLITE_OK && zSql[0] ){
     int nCol;
     char **azVals = 0;
 
     pStmt = 0;
-    rc = sqlite3_prepare(db, zSql, -1, &pStmt, &zLeftover);
+    rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, &zLeftover);
     assert( rc==SQLITE_OK || pStmt==0 );
     if( rc!=SQLITE_OK ){
       continue;
@@ -91958,11 +92442,8 @@ SQLITE_API int sqlite3_exec(
       if( rc!=SQLITE_ROW ){
         rc = sqlite3VdbeFinalize((Vdbe *)pStmt);
         pStmt = 0;
-        if( rc!=SQLITE_SCHEMA ){
-          nRetry = 0;
-          zSql = zLeftover;
-          while( sqlite3Isspace(zSql[0]) ) zSql++;
-        }
+        zSql = zLeftover;
+        while( sqlite3Isspace(zSql[0]) ) zSql++;
         break;
       }
     }
@@ -92253,6 +92734,20 @@ struct sqlite3_api_routines {
   int (*blob_reopen)(sqlite3_blob*,sqlite3_int64);
   int (*vtab_config)(sqlite3*,int op,...);
   int (*vtab_on_conflict)(sqlite3*);
+  /* Version 3.7.16 and later */
+  int (*close_v2)(sqlite3*);
+  const char *(*db_filename)(sqlite3*,const char*);
+  int (*db_readonly)(sqlite3*,const char*);
+  int (*db_release_memory)(sqlite3*);
+  const char *(*errstr)(int);
+  int (*stmt_busy)(sqlite3_stmt*);
+  int (*stmt_readonly)(sqlite3_stmt*);
+  int (*stricmp)(const char*,const char*);
+  int (*uri_boolean)(const char*,const char*,int);
+  sqlite3_int64 (*uri_int64)(const char*,const char*,sqlite3_int64);
+  const char *(*uri_parameter)(const char*,const char*);
+  char *(*vsnprintf)(int,char*,const char*,va_list);
+  int (*wal_checkpoint_v2)(sqlite3*,const char*,int,int*,int*);
 };
 
 /*
@@ -92456,10 +92951,36 @@ struct sqlite3_api_routines {
 #define sqlite3_blob_reopen            sqlite3_api->blob_reopen
 #define sqlite3_vtab_config            sqlite3_api->vtab_config
 #define sqlite3_vtab_on_conflict       sqlite3_api->vtab_on_conflict
+/* Version 3.7.16 and later */
+#define sqlite3_close_v2               sqlite3_api->close_v2
+#define sqlite3_db_filename            sqlite3_api->db_filename
+#define sqlite3_db_readonly            sqlite3_api->db_readonly
+#define sqlite3_db_release_memory      sqlite3_api->db_release_memory
+#define sqlite3_errstr                 sqlite3_api->errstr
+#define sqlite3_stmt_busy              sqlite3_api->stmt_busy
+#define sqlite3_stmt_readonly          sqlite3_api->stmt_readonly
+#define sqlite3_stricmp                sqlite3_api->stricmp
+#define sqlite3_uri_boolean            sqlite3_api->uri_boolean
+#define sqlite3_uri_int64              sqlite3_api->uri_int64
+#define sqlite3_uri_parameter          sqlite3_api->uri_parameter
+#define sqlite3_uri_vsnprintf          sqlite3_api->vsnprintf
+#define sqlite3_wal_checkpoint_v2      sqlite3_api->wal_checkpoint_v2
 #endif /* SQLITE_CORE */
 
-#define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api = 0;
-#define SQLITE_EXTENSION_INIT2(v)  sqlite3_api = v;
+#ifndef SQLITE_CORE
+  /* This case when the file really is being compiled as a loadable 
+  ** extension */
+# define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api=0;
+# define SQLITE_EXTENSION_INIT2(v)  sqlite3_api=v;
+# define SQLITE_EXTENSION_INIT3     \
+    extern const sqlite3_api_routines *sqlite3_api;
+#else
+  /* This case when the file is being statically linked into the 
+  ** application */
+# define SQLITE_EXTENSION_INIT1     /*no-op*/
+# define SQLITE_EXTENSION_INIT2(v)  (void)v; /* unused parameter */
+# define SQLITE_EXTENSION_INIT3     /*no-op*/
+#endif
 
 #endif /* _SQLITE3EXT_H_ */
 
@@ -92825,6 +93346,19 @@ static const sqlite3_api_routines sqlite3Apis = {
   sqlite3_blob_reopen,
   sqlite3_vtab_config,
   sqlite3_vtab_on_conflict,
+  sqlite3_close_v2,
+  sqlite3_db_filename,
+  sqlite3_db_readonly,
+  sqlite3_db_release_memory,
+  sqlite3_errstr,
+  sqlite3_stmt_busy,
+  sqlite3_stmt_readonly,
+  sqlite3_stricmp,
+  sqlite3_uri_boolean,
+  sqlite3_uri_int64,
+  sqlite3_uri_parameter,
+  sqlite3_vsnprintf,
+  sqlite3_wal_checkpoint_v2
 };
 
 /*
@@ -92849,8 +93383,23 @@ static int sqlite3LoadExtension(
   void *handle;
   int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);
   char *zErrmsg = 0;
+  const char *zEntry;
+  char *zAltEntry = 0;
   void **aHandle;
   int nMsg = 300 + sqlite3Strlen30(zFile);
+  int ii;
+
+  /* Shared library endings to try if zFile cannot be loaded as written */
+  static const char *azEndings[] = {
+#if SQLITE_OS_WIN
+     "dll"   
+#elif defined(__APPLE__)
+     "dylib"
+#else
+     "so"
+#endif
+  };
+
 
   if( pzErrMsg ) *pzErrMsg = 0;
 
@@ -92867,11 +93416,17 @@ static int sqlite3LoadExtension(
     return SQLITE_ERROR;
   }
 
-  if( zProc==0 ){
-    zProc = "sqlite3_extension_init";
-  }
+  zEntry = zProc ? zProc : "sqlite3_extension_init";
 
   handle = sqlite3OsDlOpen(pVfs, zFile);
+#if SQLITE_OS_UNIX || SQLITE_OS_WIN
+  for(ii=0; ii<ArraySize(azEndings) && handle==0; ii++){
+    char *zAltFile = sqlite3_mprintf("%s.%s", zFile, azEndings[ii]);
+    if( zAltFile==0 ) return SQLITE_NOMEM;
+    handle = sqlite3OsDlOpen(pVfs, zAltFile);
+    sqlite3_free(zAltFile);
+  }
+#endif
   if( handle==0 ){
     if( pzErrMsg ){
       *pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
@@ -92884,20 +93439,57 @@ static int sqlite3LoadExtension(
     return SQLITE_ERROR;
   }
   xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
-                   sqlite3OsDlSym(pVfs, handle, zProc);
+                   sqlite3OsDlSym(pVfs, handle, zEntry);
+
+  /* If no entry point was specified and the default legacy
+  ** entry point name "sqlite3_extension_init" was not found, then
+  ** construct an entry point name "sqlite3_X_init" where the X is
+  ** replaced by the lowercase value of every ASCII alphabetic 
+  ** character in the filename after the last "/" upto the first ".",
+  ** and eliding the first three characters if they are "lib".  
+  ** Examples:
+  **
+  **    /usr/local/lib/libExample5.4.3.so ==>  sqlite3_example_init
+  **    C:/lib/mathfuncs.dll              ==>  sqlite3_mathfuncs_init
+  */
+  if( xInit==0 && zProc==0 ){
+    int iFile, iEntry, c;
+    int ncFile = sqlite3Strlen30(zFile);
+    zAltEntry = sqlite3_malloc(ncFile+30);
+    if( zAltEntry==0 ){
+      sqlite3OsDlClose(pVfs, handle);
+      return SQLITE_NOMEM;
+    }
+    memcpy(zAltEntry, "sqlite3_", 8);
+    for(iFile=ncFile-1; iFile>=0 && zFile[iFile]!='/'; iFile--){}
+    iFile++;
+    if( sqlite3_strnicmp(zFile+iFile, "lib", 3)==0 ) iFile += 3;
+    for(iEntry=8; (c = zFile[iFile])!=0 && c!='.'; iFile++){
+      if( sqlite3Isalpha(c) ){
+        zAltEntry[iEntry++] = (char)sqlite3UpperToLower[(unsigned)c];
+      }
+    }
+    memcpy(zAltEntry+iEntry, "_init", 6);
+    zEntry = zAltEntry;
+    xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
+                     sqlite3OsDlSym(pVfs, handle, zEntry);
+  }
   if( xInit==0 ){
     if( pzErrMsg ){
-      nMsg += sqlite3Strlen30(zProc);
+      nMsg += sqlite3Strlen30(zEntry);
       *pzErrMsg = zErrmsg = sqlite3_malloc(nMsg);
       if( zErrmsg ){
         sqlite3_snprintf(nMsg, zErrmsg,
-            "no entry point [%s] in shared library [%s]", zProc,zFile);
+            "no entry point [%s] in shared library [%s]", zEntry, zFile);
         sqlite3OsDlError(pVfs, nMsg-1, zErrmsg);
       }
-      sqlite3OsDlClose(pVfs, handle);
     }
+    sqlite3OsDlClose(pVfs, handle);
+    sqlite3_free(zAltEntry);
     return SQLITE_ERROR;
-  }else if( xInit(db, &zErrmsg, &sqlite3Apis) ){
+  }
+  sqlite3_free(zAltEntry);
+  if( xInit(db, &zErrmsg, &sqlite3Apis) ){
     if( pzErrMsg ){
       *pzErrMsg = sqlite3_mprintf("error during initialization: %s", zErrmsg);
     }
@@ -93044,6 +93636,35 @@ SQLITE_API int sqlite3_auto_extension(void (*xInit)(void)){
   }
 }
 
+/*
+** Cancel a prior call to sqlite3_auto_extension.  Remove xInit from the
+** set of routines that is invoked for each new database connection, if it
+** is currently on the list.  If xInit is not on the list, then this
+** routine is a no-op.
+**
+** Return 1 if xInit was found on the list and removed.  Return 0 if xInit
+** was not on the list.
+*/
+SQLITE_API int sqlite3_cancel_auto_extension(void (*xInit)(void)){
+#if SQLITE_THREADSAFE
+  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+#endif
+  int i;
+  int n = 0;
+  wsdAutoextInit;
+  sqlite3_mutex_enter(mutex);
+  for(i=wsdAutoext.nExt-1; i>=0; i--){
+    if( wsdAutoext.aExt[i]==xInit ){
+      wsdAutoext.nExt--;
+      wsdAutoext.aExt[i] = wsdAutoext.aExt[wsdAutoext.nExt];
+      n++;
+      break;
+    }
+  }
+  sqlite3_mutex_leave(mutex);
+  return n;
+}
+
 /*
 ** Reset the automatic extension loading mechanism.
 */
@@ -93265,6 +93886,36 @@ static void returnSingleInt(Parse *pParse, const char *zLabel, i64 value){
   sqlite3VdbeAddOp2(v, OP_ResultRow, mem, 1);
 }
 
+
+/*
+** Set the safety_level and pager flags for pager iDb.  Or if iDb<0
+** set these values for all pagers.
+*/
+#ifndef SQLITE_OMIT_PAGER_PRAGMAS
+static void setAllPagerFlags(sqlite3 *db){
+  if( db->autoCommit ){
+    Db *pDb = db->aDb;
+    int n = db->nDb;
+    assert( SQLITE_FullFSync==PAGER_FULLFSYNC );
+    assert( SQLITE_CkptFullFSync==PAGER_CKPT_FULLFSYNC );
+    assert( SQLITE_CacheSpill==PAGER_CACHESPILL );
+    assert( (PAGER_FULLFSYNC | PAGER_CKPT_FULLFSYNC | PAGER_CACHESPILL)
+             ==  PAGER_FLAGS_MASK );
+    assert( (pDb->safety_level & PAGER_SYNCHRONOUS_MASK)==pDb->safety_level );
+    while( (n--) > 0 ){
+      if( pDb->pBt ){
+        sqlite3BtreeSetPagerFlags(pDb->pBt,
+                 pDb->safety_level | (db->flags & PAGER_FLAGS_MASK) );
+      }
+      pDb++;
+    }
+  }
+}
+#else
+# define setAllPagerFlags(X)  /* no-op */
+#endif
+
+
 #ifndef SQLITE_OMIT_FLAG_PRAGMAS
 /*
 ** Check to see if zRight and zLeft refer to a pragma that queries
@@ -93283,7 +93934,9 @@ static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
     { "legacy_file_format",       SQLITE_LegacyFileFmt },
     { "fullfsync",                SQLITE_FullFSync     },
     { "checkpoint_fullfsync",     SQLITE_CkptFullFSync },
+    { "cache_spill",              SQLITE_CacheSpill    },
     { "reverse_unordered_selects", SQLITE_ReverseOrder  },
+    { "query_only",               SQLITE_QueryOnly     },
 #ifndef SQLITE_OMIT_AUTOMATIC_INDEX
     { "automatic_index",          SQLITE_AutoIndex     },
 #endif
@@ -93291,6 +93944,9 @@ static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
     { "sql_trace",                SQLITE_SqlTrace      },
     { "vdbe_listing",             SQLITE_VdbeListing   },
     { "vdbe_trace",               SQLITE_VdbeTrace     },
+    { "vdbe_addoptrace",          SQLITE_VdbeAddopTrace},
+    { "vdbe_debug",    SQLITE_SqlTrace | SQLITE_VdbeListing
+                               | SQLITE_VdbeTrace      },
 #endif
 #ifndef SQLITE_OMIT_CHECK
     { "ignore_check_constraints", SQLITE_IgnoreChecks  },
@@ -93301,12 +93957,13 @@ static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
     /* TODO: Maybe it shouldn't be possible to change the ReadUncommitted
     ** flag if there are any active statements. */
     { "read_uncommitted",         SQLITE_ReadUncommitted },
-    { "recursive_triggers",       SQLITE_RecTriggers },
+    { "recursive_triggers",       SQLITE_RecTriggers   },
 
     /* This flag may only be set if both foreign-key and trigger support
     ** are present in the build.  */
 #if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
-    { "foreign_keys",             SQLITE_ForeignKeys },
+    { "foreign_keys",             SQLITE_ForeignKeys   },
+    { "defer_foreign_keys",       SQLITE_DeferFKs      },
 #endif
   };
   int i;
@@ -93332,6 +93989,7 @@ static int flagPragma(Parse *pParse, const char *zLeft, const char *zRight){
             db->flags |= mask;
           }else{
             db->flags &= ~mask;
+            if( mask==SQLITE_DeferFKs ) db->nDeferredImmCons = 0;
           }
 
           /* Many of the flag-pragmas modify the code generated by the SQL 
@@ -93423,7 +94081,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
   int rc;                      /* return value form SQLITE_FCNTL_PRAGMA */
   sqlite3 *db = pParse->db;    /* The database connection */
   Db *pDb;                     /* The specific database being pragmaed */
-  Vdbe *v = pParse->pVdbe = sqlite3VdbeCreate(db);  /* Prepared statement */
+  Vdbe *v = sqlite3GetVdbe(pParse);  /* Prepared statement */
 
   if( v==0 ) return;
   sqlite3VdbeRunOnlyOnce(v);
@@ -93464,6 +94122,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
   aFcntl[1] = zLeft;
   aFcntl[2] = zRight;
   aFcntl[3] = 0;
+  db->busyHandler.nBusy = 0;
   rc = sqlite3_file_control(db, zDb, SQLITE_FCNTL_PRAGMA, (void*)aFcntl);
   if( rc==SQLITE_OK ){
     if( aFcntl[0] ){
@@ -93505,11 +94164,12 @@ SQLITE_PRIVATE void sqlite3Pragma(
     static const VdbeOpList getCacheSize[] = {
       { OP_Transaction, 0, 0,        0},                         /* 0 */
       { OP_ReadCookie,  0, 1,        BTREE_DEFAULT_CACHE_SIZE},  /* 1 */
-      { OP_IfPos,       1, 7,        0},
+      { OP_IfPos,       1, 8,        0},
       { OP_Integer,     0, 2,        0},
       { OP_Subtract,    1, 2,        1},
-      { OP_IfPos,       1, 7,        0},
+      { OP_IfPos,       1, 8,        0},
       { OP_Integer,     0, 1,        0},                         /* 6 */
+      { OP_Noop,        0, 0,        0},
       { OP_ResultRow,   1, 1,        0},
     };
     int addr;
@@ -93847,6 +94507,47 @@ SQLITE_PRIVATE void sqlite3Pragma(
     }
   }else
 
+  /*
+  **  PRAGMA [database.]mmap_size(N)
+  **
+  ** Used to set mapping size limit. The mapping size limit is
+  ** used to limit the aggregate size of all memory mapped regions of the
+  ** database file. If this parameter is set to zero, then memory mapping
+  ** is not used at all.  If N is negative, then the default memory map
+  ** limit determined by sqlite3_config(SQLITE_CONFIG_MMAP_SIZE) is set.
+  ** The parameter N is measured in bytes.
+  **
+  ** This value is advisory.  The underlying VFS is free to memory map
+  ** as little or as much as it wants.  Except, if N is set to 0 then the
+  ** upper layers will never invoke the xFetch interfaces to the VFS.
+  */
+  if( sqlite3StrICmp(zLeft,"mmap_size")==0 ){
+    sqlite3_int64 sz;
+    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
+    if( zRight ){
+      int ii;
+      sqlite3Atoi64(zRight, &sz, 1000, SQLITE_UTF8);
+      if( sz<0 ) sz = sqlite3GlobalConfig.szMmap;
+      if( pId2->n==0 ) db->szMmap = sz;
+      for(ii=db->nDb-1; ii>=0; ii--){
+        if( db->aDb[ii].pBt && (ii==iDb || pId2->n==0) ){
+          sqlite3BtreeSetMmapLimit(db->aDb[ii].pBt, sz);
+        }
+      }
+    }
+    sz = -1;
+    rc = sqlite3_file_control(db, zDb, SQLITE_FCNTL_MMAP_SIZE, &sz);
+#if SQLITE_MAX_MMAP_SIZE==0
+    sz = 0;
+#endif
+    if( rc==SQLITE_OK ){
+      returnSingleInt(pParse, "mmap_size", sz);
+    }else if( rc!=SQLITE_NOTFOUND ){
+      pParse->nErr++;
+      pParse->rc = rc;
+    }
+  }else
+
   /*
   **   PRAGMA temp_store
   **   PRAGMA temp_store = "default"|"memory"|"file"
@@ -94024,6 +94725,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
             "Safety level may not be changed inside a transaction");
       }else{
         pDb->safety_level = getSafetyLevel(zRight,0,1)+1;
+        setAllPagerFlags(db);
       }
     }
   }else
@@ -94031,8 +94733,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
 
 #ifndef SQLITE_OMIT_FLAG_PRAGMAS
   if( flagPragma(pParse, zLeft, zRight) ){
-    /* The flagPragma() subroutine also generates any necessary code
-    ** there is nothing more to do here */
+    setAllPagerFlags(db);
   }else
 #endif /* SQLITE_OMIT_FLAG_PRAGMAS */
 
@@ -94054,11 +94755,14 @@ SQLITE_PRIVATE void sqlite3Pragma(
     if( sqlite3ReadSchema(pParse) ) goto pragma_out;
     pTab = sqlite3FindTable(db, zRight, zDb);
     if( pTab ){
-      int i;
+      int i, k;
       int nHidden = 0;
       Column *pCol;
+      Index *pPk;
+      for(pPk=pTab->pIndex; pPk && pPk->autoIndex!=2; pPk=pPk->pNext){}
       sqlite3VdbeSetNumCols(v, 6);
       pParse->nMem = 6;
+      sqlite3CodeVerifySchema(pParse, iDb);
       sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "cid", SQLITE_STATIC);
       sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
       sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "type", SQLITE_STATIC);
@@ -94081,7 +94785,14 @@ SQLITE_PRIVATE void sqlite3Pragma(
         }else{
           sqlite3VdbeAddOp2(v, OP_Null, 0, 5);
         }
-        sqlite3VdbeAddOp2(v, OP_Integer, pCol->isPrimKey, 6);
+        if( (pCol->colFlags & COLFLAG_PRIMKEY)==0 ){
+          k = 0;
+        }else if( pPk==0 ){
+          k = 1;
+        }else{
+          for(k=1; ALWAYS(k<=pTab->nCol) && pPk->aiColumn[k-1]!=i; k++){}
+        }
+        sqlite3VdbeAddOp2(v, OP_Integer, k, 6);
         sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 6);
       }
     }
@@ -94097,6 +94808,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
       pTab = pIdx->pTable;
       sqlite3VdbeSetNumCols(v, 3);
       pParse->nMem = 3;
+      sqlite3CodeVerifySchema(pParse, iDb);
       sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seqno", SQLITE_STATIC);
       sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "cid", SQLITE_STATIC);
       sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "name", SQLITE_STATIC);
@@ -94123,6 +94835,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
         int i = 0; 
         sqlite3VdbeSetNumCols(v, 3);
         pParse->nMem = 3;
+        sqlite3CodeVerifySchema(pParse, iDb);
         sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "seq", SQLITE_STATIC);
         sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "name", SQLITE_STATIC);
         sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "unique", SQLITE_STATIC);
@@ -94186,6 +94899,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
         int i = 0; 
         sqlite3VdbeSetNumCols(v, 8);
         pParse->nMem = 8;
+        sqlite3CodeVerifySchema(pParse, iDb);
         sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "id", SQLITE_STATIC);
         sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "seq", SQLITE_STATIC);
         sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "table", SQLITE_STATIC);
@@ -94219,6 +94933,122 @@ SQLITE_PRIVATE void sqlite3Pragma(
   }else
 #endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
 
+#ifndef SQLITE_OMIT_FOREIGN_KEY
+#ifndef SQLITE_OMIT_TRIGGER
+  if( sqlite3StrICmp(zLeft, "foreign_key_check")==0 ){
+    FKey *pFK;             /* A foreign key constraint */
+    Table *pTab;           /* Child table contain "REFERENCES" keyword */
+    Table *pParent;        /* Parent table that child points to */
+    Index *pIdx;           /* Index in the parent table */
+    int i;                 /* Loop counter:  Foreign key number for pTab */
+    int j;                 /* Loop counter:  Field of the foreign key */
+    HashElem *k;           /* Loop counter:  Next table in schema */
+    int x;                 /* result variable */
+    int regResult;         /* 3 registers to hold a result row */
+    int regKey;            /* Register to hold key for checking the FK */
+    int regRow;            /* Registers to hold a row from pTab */
+    int addrTop;           /* Top of a loop checking foreign keys */
+    int addrOk;            /* Jump here if the key is OK */
+    int *aiCols;           /* child to parent column mapping */
+
+    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
+    regResult = pParse->nMem+1;
+    pParse->nMem += 4;
+    regKey = ++pParse->nMem;
+    regRow = ++pParse->nMem;
+    v = sqlite3GetVdbe(pParse);
+    sqlite3VdbeSetNumCols(v, 4);
+    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "table", SQLITE_STATIC);
+    sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "rowid", SQLITE_STATIC);
+    sqlite3VdbeSetColName(v, 2, COLNAME_NAME, "parent", SQLITE_STATIC);
+    sqlite3VdbeSetColName(v, 3, COLNAME_NAME, "fkid", SQLITE_STATIC);
+    sqlite3CodeVerifySchema(pParse, iDb);
+    k = sqliteHashFirst(&db->aDb[iDb].pSchema->tblHash);
+    while( k ){
+      if( zRight ){
+        pTab = sqlite3LocateTable(pParse, 0, zRight, zDb);
+        k = 0;
+      }else{
+        pTab = (Table*)sqliteHashData(k);
+        k = sqliteHashNext(k);
+      }
+      if( pTab==0 || pTab->pFKey==0 ) continue;
+      sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
+      if( pTab->nCol+regRow>pParse->nMem ) pParse->nMem = pTab->nCol + regRow;
+      sqlite3OpenTable(pParse, 0, iDb, pTab, OP_OpenRead);
+      sqlite3VdbeAddOp4(v, OP_String8, 0, regResult, 0, pTab->zName,
+                        P4_TRANSIENT);
+      for(i=1, pFK=pTab->pFKey; pFK; i++, pFK=pFK->pNextFrom){
+        pParent = sqlite3LocateTable(pParse, 0, pFK->zTo, zDb);
+        if( pParent==0 ) break;
+        pIdx = 0;
+        sqlite3TableLock(pParse, iDb, pParent->tnum, 0, pParent->zName);
+        x = sqlite3FkLocateIndex(pParse, pParent, pFK, &pIdx, 0);
+        if( x==0 ){
+          if( pIdx==0 ){
+            sqlite3OpenTable(pParse, i, iDb, pParent, OP_OpenRead);
+          }else{
+            KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
+            sqlite3VdbeAddOp3(v, OP_OpenRead, i, pIdx->tnum, iDb);
+            sqlite3VdbeChangeP4(v, -1, (char*)pKey, P4_KEYINFO_HANDOFF);
+          }
+        }else{
+          k = 0;
+          break;
+        }
+      }
+      if( pFK ) break;
+      if( pParse->nTab<i ) pParse->nTab = i;
+      addrTop = sqlite3VdbeAddOp1(v, OP_Rewind, 0);
+      for(i=1, pFK=pTab->pFKey; pFK; i++, pFK=pFK->pNextFrom){
+        pParent = sqlite3LocateTable(pParse, 0, pFK->zTo, zDb);
+        assert( pParent!=0 );
+        pIdx = 0;
+        aiCols = 0;
+        x = sqlite3FkLocateIndex(pParse, pParent, pFK, &pIdx, &aiCols);
+        assert( x==0 );
+        addrOk = sqlite3VdbeMakeLabel(v);
+        if( pIdx==0 ){
+          int iKey = pFK->aCol[0].iFrom;
+          assert( iKey>=0 && iKey<pTab->nCol );
+          if( iKey!=pTab->iPKey ){
+            sqlite3VdbeAddOp3(v, OP_Column, 0, iKey, regRow);
+            sqlite3ColumnDefault(v, pTab, iKey, regRow);
+            sqlite3VdbeAddOp2(v, OP_IsNull, regRow, addrOk);
+            sqlite3VdbeAddOp2(v, OP_MustBeInt, regRow,
+               sqlite3VdbeCurrentAddr(v)+3);
+          }else{
+            sqlite3VdbeAddOp2(v, OP_Rowid, 0, regRow);
+          }
+          sqlite3VdbeAddOp3(v, OP_NotExists, i, 0, regRow);
+          sqlite3VdbeAddOp2(v, OP_Goto, 0, addrOk);
+          sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);
+        }else{
+          for(j=0; j<pFK->nCol; j++){
+            sqlite3ExprCodeGetColumnOfTable(v, pTab, 0,
+                            aiCols ? aiCols[j] : pFK->aCol[0].iFrom, regRow+j);
+            sqlite3VdbeAddOp2(v, OP_IsNull, regRow+j, addrOk);
+          }
+          sqlite3VdbeAddOp3(v, OP_MakeRecord, regRow, pFK->nCol, regKey);
+          sqlite3VdbeChangeP4(v, -1,
+                   sqlite3IndexAffinityStr(v,pIdx), P4_TRANSIENT);
+          sqlite3VdbeAddOp4Int(v, OP_Found, i, addrOk, regKey, 0);
+        }
+        sqlite3VdbeAddOp2(v, OP_Rowid, 0, regResult+1);
+        sqlite3VdbeAddOp4(v, OP_String8, 0, regResult+2, 0, 
+                          pFK->zTo, P4_TRANSIENT);
+        sqlite3VdbeAddOp2(v, OP_Integer, i-1, regResult+3);
+        sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, 4);
+        sqlite3VdbeResolveLabel(v, addrOk);
+        sqlite3DbFree(db, aiCols);
+      }
+      sqlite3VdbeAddOp2(v, OP_Next, 0, addrTop+1);
+      sqlite3VdbeJumpHere(v, addrTop);
+    }
+  }else
+#endif /* !defined(SQLITE_OMIT_TRIGGER) */
+#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
+
 #ifndef NDEBUG
   if( sqlite3StrICmp(zLeft, "parser_trace")==0 ){
     if( zRight ){
@@ -94245,7 +95075,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
 #endif
 
 #ifndef SQLITE_OMIT_INTEGRITY_CHECK
-  /* Pragma "quick_check" is an experimental reduced version of 
+  /* Pragma "quick_check" is reduced version of 
   ** integrity_check designed to detect most database corruption
   ** without most of the overhead of a full integrity-check.
   */
@@ -94267,6 +95097,19 @@ SQLITE_PRIVATE void sqlite3Pragma(
 
     int isQuick = (sqlite3Tolower(zLeft[0])=='q');
 
+    /* If the PRAGMA command was of the form "PRAGMA <db>.integrity_check",
+    ** then iDb is set to the index of the database identified by <db>.
+    ** In this case, the integrity of database iDb only is verified by
+    ** the VDBE created below.
+    **
+    ** Otherwise, if the command was simply "PRAGMA integrity_check" (or
+    ** "PRAGMA quick_check"), then iDb is set to 0. In this case, set iDb
+    ** to -1 here, to indicate that the VDBE should verify the integrity
+    ** of all attached databases.  */
+    assert( iDb>=0 );
+    assert( iDb==0 || pId2->z );
+    if( pId2->z==0 ) iDb = -1;
+
     /* Initialize the VDBE program */
     if( sqlite3ReadSchema(pParse) ) goto pragma_out;
     pParse->nMem = 6;
@@ -94290,6 +95133,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
       int cnt = 0;
 
       if( OMIT_TEMPDB && i==1 ) continue;
+      if( iDb>=0 && i!=iDb ) continue;
 
       sqlite3CodeVerifySchema(pParse, i);
       addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1); /* Halt if out of errors */
@@ -94301,7 +95145,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
       ** Begin by filling registers 2, 3, ... with the root pages numbers
       ** for all tables and indices in the database.
       */
-      assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
+      assert( sqlite3SchemaMutexHeld(db, i, 0) );
       pTbls = &db->aDb[i].pSchema->tblHash;
       for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
         Table *pTab = sqliteHashData(x);
@@ -94315,9 +95159,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
       }
 
       /* Make sure sufficient number of registers have been allocated */
-      if( pParse->nMem < cnt+4 ){
-        pParse->nMem = cnt+4;
-      }
+      pParse->nMem = MAX( pParse->nMem, cnt+7 );
 
       /* Do the b-tree integrity checks */
       sqlite3VdbeAddOp3(v, OP_IntegrityCk, 2, cnt, 1);
@@ -94326,7 +95168,7 @@ SQLITE_PRIVATE void sqlite3Pragma(
       sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0,
          sqlite3MPrintf(db, "*** in database %s ***\n", db->aDb[i].zName),
          P4_DYNAMIC);
-      sqlite3VdbeAddOp3(v, OP_Move, 2, 4, 1);
+      sqlite3VdbeAddOp2(v, OP_Move, 2, 4);
       sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 2);
       sqlite3VdbeAddOp2(v, OP_ResultRow, 2, 1);
       sqlite3VdbeJumpHere(v, addr);
@@ -94342,12 +95184,15 @@ SQLITE_PRIVATE void sqlite3Pragma(
         addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);  /* Stop if out of errors */
         sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
         sqlite3VdbeJumpHere(v, addr);
+        sqlite3ExprCacheClear(pParse);
         sqlite3OpenTableAndIndices(pParse, pTab, 1, OP_OpenRead);
-        sqlite3VdbeAddOp2(v, OP_Integer, 0, 2);  /* reg(2) will count entries */
-        loopTop = sqlite3VdbeAddOp2(v, OP_Rewind, 1, 0);
-        sqlite3VdbeAddOp2(v, OP_AddImm, 2, 1);   /* increment entry count */
         for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
-          int jmp2;
+          sqlite3VdbeAddOp2(v, OP_Integer, 0, 7+j); /* index entries counter */
+        }
+        pParse->nMem = MAX(pParse->nMem, 7+j);
+        loopTop = sqlite3VdbeAddOp2(v, OP_Rewind, 1, 0) + 1;
+        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
+          int jmp2, jmp3;
           int r1;
           static const VdbeOpList idxErr[] = {
             { OP_AddImm,      1, -1,  0},
@@ -94362,7 +95207,8 @@ SQLITE_PRIVATE void sqlite3Pragma(
             { OP_IfPos,       1,  0,  0},    /* 9 */
             { OP_Halt,        0,  0,  0},
           };
-          r1 = sqlite3GenerateIndexKey(pParse, pIdx, 1, 3, 0);
+          r1 = sqlite3GenerateIndexKey(pParse, pIdx, 1, 3, 0, &jmp3);
+          sqlite3VdbeAddOp2(v, OP_AddImm, 7+j, 1);  /* increment entry count */
           jmp2 = sqlite3VdbeAddOp4Int(v, OP_Found, j+2, 0, r1, pIdx->nColumn+1);
           addr = sqlite3VdbeAddOpList(v, ArraySize(idxErr), idxErr);
           sqlite3VdbeChangeP4(v, addr+1, "rowid ", P4_STATIC);
@@ -94370,35 +95216,25 @@ SQLITE_PRIVATE void sqlite3Pragma(
           sqlite3VdbeChangeP4(v, addr+4, pIdx->zName, P4_TRANSIENT);
           sqlite3VdbeJumpHere(v, addr+9);
           sqlite3VdbeJumpHere(v, jmp2);
+          sqlite3VdbeResolveLabel(v, jmp3);
         }
-        sqlite3VdbeAddOp2(v, OP_Next, 1, loopTop+1);
-        sqlite3VdbeJumpHere(v, loopTop);
-        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
-          static const VdbeOpList cntIdx[] = {
-             { OP_Integer,      0,  3,  0},
-             { OP_Rewind,       0,  0,  0},  /* 1 */
-             { OP_AddImm,       3,  1,  0},
-             { OP_Next,         0,  0,  0},  /* 3 */
-             { OP_Eq,           2,  0,  3},  /* 4 */
-             { OP_AddImm,       1, -1,  0},
-             { OP_String8,      0,  2,  0},  /* 6 */
-             { OP_String8,      0,  3,  0},  /* 7 */
-             { OP_Concat,       3,  2,  2},
-             { OP_ResultRow,    2,  1,  0},
-          };
-          addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1);
-          sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
-          sqlite3VdbeJumpHere(v, addr);
-          addr = sqlite3VdbeAddOpList(v, ArraySize(cntIdx), cntIdx);
-          sqlite3VdbeChangeP1(v, addr+1, j+2);
-          sqlite3VdbeChangeP2(v, addr+1, addr+4);
-          sqlite3VdbeChangeP1(v, addr+3, j+2);
-          sqlite3VdbeChangeP2(v, addr+3, addr+2);
-          sqlite3VdbeJumpHere(v, addr+4);
-          sqlite3VdbeChangeP4(v, addr+6, 
+        sqlite3VdbeAddOp2(v, OP_Next, 1, loopTop);
+        sqlite3VdbeJumpHere(v, loopTop-1);
+#ifndef SQLITE_OMIT_BTREECOUNT
+        sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, 
                      "wrong # of entries in index ", P4_STATIC);
-          sqlite3VdbeChangeP4(v, addr+7, pIdx->zName, P4_TRANSIENT);
+        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
+          addr = sqlite3VdbeCurrentAddr(v);
+          sqlite3VdbeAddOp2(v, OP_IfPos, 1, addr+2);
+          sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
+          sqlite3VdbeAddOp2(v, OP_Count, j+2, 3);
+          sqlite3VdbeAddOp3(v, OP_Eq, 7+j, addr+8, 3);
+          sqlite3VdbeAddOp2(v, OP_AddImm, 1, -1);
+          sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, pIdx->zName, P4_TRANSIENT);
+          sqlite3VdbeAddOp3(v, OP_Concat, 3, 2, 7);
+          sqlite3VdbeAddOp2(v, OP_ResultRow, 7, 1);
         }
+#endif /* SQLITE_OMIT_BTREECOUNT */
       } 
     }
     addr = sqlite3VdbeAddOpList(v, ArraySize(endCode), endCode);
@@ -94489,6 +95325,11 @@ SQLITE_PRIVATE void sqlite3Pragma(
   **   PRAGMA [database.]user_version
   **   PRAGMA [database.]user_version = <integer>
   **
+  **   PRAGMA [database.]freelist_count = <integer>
+  **
+  **   PRAGMA [database.]application_id
+  **   PRAGMA [database.]application_id = <integer>
+  **
   ** The pragma's schema_version and user_version are used to set or get
   ** the value of the schema-version and user-version, respectively. Both
   ** the schema-version and the user-version are 32-bit signed integers
@@ -94510,10 +95351,14 @@ SQLITE_PRIVATE void sqlite3Pragma(
   if( sqlite3StrICmp(zLeft, "schema_version")==0 
    || sqlite3StrICmp(zLeft, "user_version")==0 
    || sqlite3StrICmp(zLeft, "freelist_count")==0 
+   || sqlite3StrICmp(zLeft, "application_id")==0 
   ){
     int iCookie;   /* Cookie index. 1 for schema-cookie, 6 for user-cookie. */
     sqlite3VdbeUsesBtree(v, iDb);
     switch( zLeft[0] ){
+      case 'a': case 'A':
+        iCookie = BTREE_APPLICATION_ID;
+        break;
       case 'f': case 'F':
         iCookie = BTREE_FREE_PAGE_COUNT;
         break;
@@ -94629,6 +95474,22 @@ SQLITE_PRIVATE void sqlite3Pragma(
     sqlite3_db_release_memory(db);
   }else
 
+  /*
+  **   PRAGMA busy_timeout
+  **   PRAGMA busy_timeout = N
+  **
+  ** Call sqlite3_busy_timeout(db, N).  Return the current timeout value
+  ** if one is set.  If no busy handler or a different busy handler is set
+  ** then 0 is returned.  Setting the busy_timeout to 0 or negative
+  ** disables the timeout.
+  */
+  if( sqlite3StrICmp(zLeft, "busy_timeout")==0 ){
+    if( zRight ){
+      sqlite3_busy_timeout(db, sqlite3Atoi(zRight));
+    }
+    returnSingleInt(pParse, "timeout",  db->busyTimeout);
+  }else
+
 #if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
   /*
   ** Report the current state of file logs for all databases
@@ -94644,13 +95505,12 @@ SQLITE_PRIVATE void sqlite3Pragma(
     sqlite3VdbeSetColName(v, 1, COLNAME_NAME, "status", SQLITE_STATIC);
     for(i=0; i<db->nDb; i++){
       Btree *pBt;
-      Pager *pPager;
       const char *zState = "unknown";
       int j;
       if( db->aDb[i].zName==0 ) continue;
       sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, db->aDb[i].zName, P4_STATIC);
       pBt = db->aDb[i].pBt;
-      if( pBt==0 || (pPager = sqlite3BtreePager(pBt))==0 ){
+      if( pBt==0 || sqlite3BtreePager(pBt)==0 ){
         zState = "closed";
       }else if( sqlite3_file_control(db, i ? db->aDb[i].zName : 0, 
                                      SQLITE_FCNTL_LOCKSTATE, &j)==SQLITE_OK ){
@@ -94665,10 +95525,10 @@ SQLITE_PRIVATE void sqlite3Pragma(
 
 #ifdef SQLITE_HAS_CODEC
   if( sqlite3StrICmp(zLeft, "key")==0 && zRight ){
-    sqlite3_key(db, zRight, sqlite3Strlen30(zRight));
+    sqlite3_key_v2(db, zDb, zRight, sqlite3Strlen30(zRight));
   }else
   if( sqlite3StrICmp(zLeft, "rekey")==0 && zRight ){
-    sqlite3_rekey(db, zRight, sqlite3Strlen30(zRight));
+    sqlite3_rekey_v2(db, zDb, zRight, sqlite3Strlen30(zRight));
   }else
   if( zRight && (sqlite3StrICmp(zLeft, "hexkey")==0 ||
                  sqlite3StrICmp(zLeft, "hexrekey")==0) ){
@@ -94680,14 +95540,14 @@ SQLITE_PRIVATE void sqlite3Pragma(
       zKey[i/2] = (h2 & 0x0f) | ((h1 & 0xf)<<4);
     }
     if( (zLeft[3] & 0xf)==0xb ){
-      sqlite3_key(db, zKey, i/2);
+      sqlite3_key_v2(db, zDb, zKey, i/2);
     }else{
-      sqlite3_rekey(db, zKey, i/2);
+      sqlite3_rekey_v2(db, zDb, zKey, i/2);
     }
   }else
 #endif
 #if defined(SQLITE_HAS_CODEC) || defined(SQLITE_ENABLE_CEROD)
-  if( sqlite3StrICmp(zLeft, "activate_extensions")==0 ){
+  if( sqlite3StrICmp(zLeft, "activate_extensions")==0 && zRight ){
 #ifdef SQLITE_HAS_CODEC
     if( sqlite3StrNICmp(zRight, "see-", 4)==0 ){
       sqlite3_activate_see(&zRight[4]);
@@ -94704,17 +95564,6 @@ SQLITE_PRIVATE void sqlite3Pragma(
  
   {/* Empty ELSE clause */}
 
-  /*
-  ** Reset the safety level, in case the fullfsync flag or synchronous
-  ** setting changed.
-  */
-#ifndef SQLITE_OMIT_PAGER_PRAGMAS
-  if( db->autoCommit ){
-    sqlite3BtreeSetSafetyLevel(pDb->pBt, pDb->safety_level,
-               (db->flags&SQLITE_FullFSync)!=0,
-               (db->flags&SQLITE_CkptFullFSync)!=0);
-  }
-#endif
 pragma_out:
   sqlite3DbFree(db, zLeft);
   sqlite3DbFree(db, zRight);
@@ -94859,7 +95708,9 @@ SQLITE_PRIVATE int sqlite3InitCallback(void *pInit, int argc, char **argv, char
 static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
   int rc;
   int i;
+#ifndef SQLITE_OMIT_DEPRECATED
   int size;
+#endif
   Table *pTab;
   Db *pDb;
   char const *azArg[4];
@@ -94902,7 +95753,7 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
 
   /* zMasterSchema and zInitScript are set to point at the master schema
   ** and initialisation script appropriate for the database being
-  ** initialised. zMasterName is the name of the master table.
+  ** initialized. zMasterName is the name of the master table.
   */
   if( !OMIT_TEMPDB && iDb==1 ){
     zMasterSchema = temp_master_schema;
@@ -94982,11 +95833,15 @@ static int sqlite3InitOne(sqlite3 *db, int iDb, char **pzErrMsg){
   */
   if( meta[BTREE_TEXT_ENCODING-1] ){  /* text encoding */
     if( iDb==0 ){
+#ifndef SQLITE_OMIT_UTF16
       u8 encoding;
       /* If opening the main database, set ENC(db). */
       encoding = (u8)meta[BTREE_TEXT_ENCODING-1] & 3;
       if( encoding==0 ) encoding = SQLITE_UTF8;
       ENC(db) = encoding;
+#else
+      ENC(db) = SQLITE_UTF8;
+#endif
     }else{
       /* If opening an attached database, the encoding much match ENC(db) */
       if( meta[BTREE_TEXT_ENCODING-1]!=ENC(db) ){
@@ -95123,7 +95978,7 @@ SQLITE_PRIVATE int sqlite3Init(sqlite3 *db, char **pzErrMsg){
     }
   }
 
-  /* Once all the other databases have been initialised, load the schema
+  /* Once all the other databases have been initialized, load the schema
   ** for the TEMP database. This is loaded last, as the TEMP database
   ** schema may contain references to objects in other databases.
   */
@@ -95146,7 +96001,7 @@ SQLITE_PRIVATE int sqlite3Init(sqlite3 *db, char **pzErrMsg){
 }
 
 /*
-** This routine is a no-op if the database schema is already initialised.
+** This routine is a no-op if the database schema is already initialized.
 ** Otherwise, the schema is loaded. An error code is returned.
 */
 SQLITE_PRIVATE int sqlite3ReadSchema(Parse *pParse){
@@ -95311,7 +96166,7 @@ static int sqlite3Prepare(
   sqlite3VtabUnlockList(db);
 
   pParse->db = db;
-  pParse->nQueryLoop = (double)1;
+  pParse->nQueryLoop = 0;  /* Logarithmic, so 0 really means 1 */
   if( nBytes>=0 && (nBytes==0 || zSql[nBytes-1]!=0) ){
     char *zSqlCopy;
     int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
@@ -95333,7 +96188,7 @@ static int sqlite3Prepare(
   }else{
     sqlite3RunParser(pParse, zSql, &zErrMsg);
   }
-  assert( 1==(int)pParse->nQueryLoop );
+  assert( 0==pParse->nQueryLoop );
 
   if( db->mallocFailed ){
     pParse->rc = SQLITE_NOMEM;
@@ -95373,7 +96228,6 @@ static int sqlite3Prepare(
   }
 #endif
 
-  assert( db->init.busy==0 || saveSqlFlag==0 );
   if( db->init.busy==0 ){
     Vdbe *pVdbe = pParse->pVdbe;
     sqlite3VdbeSetSql(pVdbe, zSql, (int)(pParse->zTail-zSql), saveSqlFlag);
@@ -95530,6 +96384,12 @@ static int sqlite3Prepare16(
   if( !sqlite3SafetyCheckOk(db) ){
     return SQLITE_MISUSE_BKPT;
   }
+  if( nBytes>=0 ){
+    int sz;
+    const char *z = (const char*)zSql;
+    for(sz=0; sz<nBytes && (z[sz]!=0 || z[sz+1]!=0); sz += 2){}
+    nBytes = sz;
+  }
   sqlite3_mutex_enter(db->mutex);
   zSql8 = sqlite3Utf16to8(db, zSql, nBytes, SQLITE_UTF16NATIVE);
   if( zSql8 ){
@@ -95625,10 +96485,10 @@ static void clearSelect(sqlite3 *db, Select *p){
 */
 SQLITE_PRIVATE void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iParm){
   pDest->eDest = (u8)eDest;
-  pDest->iParm = iParm;
-  pDest->affinity = 0;
-  pDest->iMem = 0;
-  pDest->nMem = 0;
+  pDest->iSDParm = iParm;
+  pDest->affSdst = 0;
+  pDest->iSdst = 0;
+  pDest->nSdst = 0;
 }
 
 
@@ -95644,7 +96504,7 @@ SQLITE_PRIVATE Select *sqlite3SelectNew(
   ExprList *pGroupBy,   /* the GROUP BY clause */
   Expr *pHaving,        /* the HAVING clause */
   ExprList *pOrderBy,   /* the ORDER BY clause */
-  int isDistinct,       /* true if the DISTINCT keyword is present */
+  u16 selFlags,         /* Flag parameters, such as SF_Distinct */
   Expr *pLimit,         /* LIMIT value.  NULL means not used */
   Expr *pOffset         /* OFFSET value.  NULL means no offset */
 ){
@@ -95668,7 +96528,7 @@ SQLITE_PRIVATE Select *sqlite3SelectNew(
   pNew->pGroupBy = pGroupBy;
   pNew->pHaving = pHaving;
   pNew->pOrderBy = pOrderBy;
-  pNew->selFlags = isDistinct ? SF_Distinct : 0;
+  pNew->selFlags = selFlags;
   pNew->op = TK_SELECT;
   pNew->pLimit = pLimit;
   pNew->pOffset = pOffset;
@@ -95698,7 +96558,7 @@ SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3 *db, Select *p){
 }
 
 /*
-** Given 1 to 3 identifiers preceeding the JOIN keyword, determine the
+** Given 1 to 3 identifiers preceding the JOIN keyword, determine the
 ** type of join.  Return an integer constant that expresses that type
 ** in terms of the following bit values:
 **
@@ -96114,6 +96974,19 @@ static int checkForMultiColumnSelectError(
 }
 #endif
 
+/*
+** An instance of the following object is used to record information about
+** how to process the DISTINCT keyword, to simplify passing that information
+** into the selectInnerLoop() routine.
+*/
+typedef struct DistinctCtx DistinctCtx;
+struct DistinctCtx {
+  u8 isTnct;      /* True if the DISTINCT keyword is present */
+  u8 eTnctType;   /* One of the WHERE_DISTINCT_* operators */
+  int tabTnct;    /* Ephemeral table used for DISTINCT processing */
+  int addrTnct;   /* Address of OP_OpenEphemeral opcode for tabTnct */
+};
+
 /*
 ** This routine generates the code for the inside of the inner loop
 ** of a SELECT.
@@ -96130,7 +97003,7 @@ static void selectInnerLoop(
   int srcTab,             /* Pull data from this table */
   int nColumn,            /* Number of columns in the source table */
   ExprList *pOrderBy,     /* If not NULL, sort results using this key */
-  int distinct,           /* If >=0, make sure results are distinct */
+  DistinctCtx *pDistinct, /* If not NULL, info on how to process DISTINCT */
   SelectDest *pDest,      /* How to dispose of the results */
   int iContinue,          /* Jump here to continue with next row */
   int iBreak              /* Jump here to break out of the inner loop */
@@ -96140,13 +97013,13 @@ static void selectInnerLoop(
   int hasDistinct;        /* True if the DISTINCT keyword is present */
   int regResult;              /* Start of memory holding result set */
   int eDest = pDest->eDest;   /* How to dispose of results */
-  int iParm = pDest->iParm;   /* First argument to disposal method */
+  int iParm = pDest->iSDParm; /* First argument to disposal method */
   int nResultCol;             /* Number of result columns */
 
   assert( v );
   if( NEVER(v==0) ) return;
   assert( pEList!=0 );
-  hasDistinct = distinct>=0;
+  hasDistinct = pDistinct ? pDistinct->eTnctType : WHERE_DISTINCT_NOOP;
   if( pOrderBy==0 && !hasDistinct ){
     codeOffset(v, p, iContinue);
   }
@@ -96158,14 +97031,14 @@ static void selectInnerLoop(
   }else{
     nResultCol = pEList->nExpr;
   }
-  if( pDest->iMem==0 ){
-    pDest->iMem = pParse->nMem+1;
-    pDest->nMem = nResultCol;
+  if( pDest->iSdst==0 ){
+    pDest->iSdst = pParse->nMem+1;
+    pDest->nSdst = nResultCol;
     pParse->nMem += nResultCol;
   }else{ 
-    assert( pDest->nMem==nResultCol );
+    assert( pDest->nSdst==nResultCol );
   }
-  regResult = pDest->iMem;
+  regResult = pDest->iSdst;
   if( nColumn>0 ){
     for(i=0; i<nColumn; i++){
       sqlite3VdbeAddOp3(v, OP_Column, srcTab, i, regResult+i);
@@ -96186,7 +97059,55 @@ static void selectInnerLoop(
   if( hasDistinct ){
     assert( pEList!=0 );
     assert( pEList->nExpr==nColumn );
-    codeDistinct(pParse, distinct, iContinue, nColumn, regResult);
+    switch( pDistinct->eTnctType ){
+      case WHERE_DISTINCT_ORDERED: {
+        VdbeOp *pOp;            /* No longer required OpenEphemeral instr. */
+        int iJump;              /* Jump destination */
+        int regPrev;            /* Previous row content */
+
+        /* Allocate space for the previous row */
+        regPrev = pParse->nMem+1;
+        pParse->nMem += nColumn;
+
+        /* Change the OP_OpenEphemeral coded earlier to an OP_Null
+        ** sets the MEM_Cleared bit on the first register of the
+        ** previous value.  This will cause the OP_Ne below to always
+        ** fail on the first iteration of the loop even if the first
+        ** row is all NULLs.
+        */
+        sqlite3VdbeChangeToNoop(v, pDistinct->addrTnct);
+        pOp = sqlite3VdbeGetOp(v, pDistinct->addrTnct);
+        pOp->opcode = OP_Null;
+        pOp->p1 = 1;
+        pOp->p2 = regPrev;
+
+        iJump = sqlite3VdbeCurrentAddr(v) + nColumn;
+        for(i=0; i<nColumn; i++){
+          CollSeq *pColl = sqlite3ExprCollSeq(pParse, pEList->a[i].pExpr);
+          if( i<nColumn-1 ){
+            sqlite3VdbeAddOp3(v, OP_Ne, regResult+i, iJump, regPrev+i);
+          }else{
+            sqlite3VdbeAddOp3(v, OP_Eq, regResult+i, iContinue, regPrev+i);
+          }
+          sqlite3VdbeChangeP4(v, -1, (const char *)pColl, P4_COLLSEQ);
+          sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
+        }
+        assert( sqlite3VdbeCurrentAddr(v)==iJump );
+        sqlite3VdbeAddOp3(v, OP_Copy, regResult, regPrev, nColumn-1);
+        break;
+      }
+
+      case WHERE_DISTINCT_UNIQUE: {
+        sqlite3VdbeChangeToNoop(v, pDistinct->addrTnct);
+        break;
+      }
+
+      default: {
+        assert( pDistinct->eTnctType==WHERE_DISTINCT_UNORDERED );
+        codeDistinct(pParse, pDistinct->tabTnct, iContinue, nColumn, regResult);
+        break;
+      }
+    }
     if( pOrderBy==0 ){
       codeOffset(v, p, iContinue);
     }
@@ -96244,7 +97165,8 @@ static void selectInnerLoop(
     */
     case SRT_Set: {
       assert( nColumn==1 );
-      p->affinity = sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affinity);
+      pDest->affSdst =
+                  sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affSdst);
       if( pOrderBy ){
         /* At first glance you would think we could optimize out the
         ** ORDER BY in this case since the order of entries in the set
@@ -96253,7 +97175,7 @@ static void selectInnerLoop(
         pushOntoSorter(pParse, pOrderBy, p, regResult);
       }else{
         int r1 = sqlite3GetTempReg(pParse);
-        sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult, 1, r1, &p->affinity, 1);
+        sqlite3VdbeAddOp4(v, OP_MakeRecord, regResult,1,r1, &pDest->affSdst, 1);
         sqlite3ExprCacheAffinityChange(pParse, regResult, 1);
         sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, r1);
         sqlite3ReleaseTempReg(pParse, r1);
@@ -96299,7 +97221,7 @@ static void selectInnerLoop(
         pushOntoSorter(pParse, pOrderBy, p, r1);
         sqlite3ReleaseTempReg(pParse, r1);
       }else if( eDest==SRT_Coroutine ){
-        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
+        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
       }else{
         sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nColumn);
         sqlite3ExprCacheAffinityChange(pParse, regResult, nColumn);
@@ -96329,6 +97251,25 @@ static void selectInnerLoop(
   }
 }
 
+/*
+** Allocate a KeyInfo object sufficient for an index of N columns.
+**
+** Actually, always allocate one extra column for the rowid at the end
+** of the index.  So the KeyInfo returned will have space sufficient for
+** N+1 columns.
+*/
+SQLITE_PRIVATE KeyInfo *sqlite3KeyInfoAlloc(sqlite3 *db, int N){
+  KeyInfo *p = sqlite3DbMallocZero(db, 
+                   sizeof(KeyInfo) + (N+1)*(sizeof(CollSeq*)+1));
+  if( p ){
+    p->aSortOrder = (u8*)&p->aColl[N+1];
+    p->nField = (u16)N;
+    p->enc = ENC(db);
+    p->db = db;
+  }
+  return p;
+}
+
 /*
 ** Given an expression list, generate a KeyInfo structure that records
 ** the collating sequence for each expression in that expression list.
@@ -96345,25 +97286,19 @@ static void selectInnerLoop(
 ** P4_KEYINFO_HANDOFF is the usual way of dealing with this.
 */
 static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList){
-  sqlite3 *db = pParse->db;
   int nExpr;
   KeyInfo *pInfo;
   struct ExprList_item *pItem;
+  sqlite3 *db = pParse->db;
   int i;
 
   nExpr = pList->nExpr;
-  pInfo = sqlite3DbMallocZero(db, sizeof(*pInfo) + nExpr*(sizeof(CollSeq*)+1) );
+  pInfo = sqlite3KeyInfoAlloc(db, nExpr);
   if( pInfo ){
-    pInfo->aSortOrder = (u8*)&pInfo->aColl[nExpr];
-    pInfo->nField = (u16)nExpr;
-    pInfo->enc = ENC(db);
-    pInfo->db = db;
     for(i=0, pItem=pList->a; i<nExpr; i++, pItem++){
       CollSeq *pColl;
       pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
-      if( !pColl ){
-        pColl = db->pDfltColl;
-      }
+      if( !pColl ) pColl = db->pDfltColl;
       pInfo->aColl[i] = pColl;
       pInfo->aSortOrder[i] = pItem->sortOrder;
     }
@@ -96479,7 +97414,7 @@ static void generateSortTail(
   ExprList *pOrderBy = p->pOrderBy;
 
   int eDest = pDest->eDest;
-  int iParm = pDest->iParm;
+  int iParm = pDest->iSDParm;
 
   int regRow;
   int regRowid;
@@ -96520,7 +97455,8 @@ static void generateSortTail(
 #ifndef SQLITE_OMIT_SUBQUERY
     case SRT_Set: {
       assert( nColumn==1 );
-      sqlite3VdbeAddOp4(v, OP_MakeRecord, regRow, 1, regRowid, &p->affinity, 1);
+      sqlite3VdbeAddOp4(v, OP_MakeRecord, regRow, 1, regRowid,
+                        &pDest->affSdst, 1);
       sqlite3ExprCacheAffinityChange(pParse, regRow, 1);
       sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm, regRowid);
       break;
@@ -96538,17 +97474,17 @@ static void generateSortTail(
       testcase( eDest==SRT_Output );
       testcase( eDest==SRT_Coroutine );
       for(i=0; i<nColumn; i++){
-        assert( regRow!=pDest->iMem+i );
-        sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iMem+i);
+        assert( regRow!=pDest->iSdst+i );
+        sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iSdst+i);
         if( i==0 ){
           sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE);
         }
       }
       if( eDest==SRT_Output ){
-        sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iMem, nColumn);
-        sqlite3ExprCacheAffinityChange(pParse, pDest->iMem, nColumn);
+        sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iSdst, nColumn);
+        sqlite3ExprCacheAffinityChange(pParse, pDest->iSdst, nColumn);
       }else{
-        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
+        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
       }
       break;
     }
@@ -96835,7 +97771,7 @@ static void generateColumnNames(
 static int selectColumnsFromExprList(
   Parse *pParse,          /* Parsing context */
   ExprList *pEList,       /* Expr list from which to derive column names */
-  int *pnCol,             /* Write the number of columns here */
+  i16 *pnCol,             /* Write the number of columns here */
   Column **paCol          /* Write the new column list here */
 ){
   sqlite3 *db = pParse->db;   /* Database connection */
@@ -96861,9 +97797,7 @@ static int selectColumnsFromExprList(
   for(i=0, pCol=aCol; i<nCol; i++, pCol++){
     /* Get an appropriate name for the column
     */
-    p = pEList->a[i].pExpr;
-    assert( p->pRight==0 || ExprHasProperty(p->pRight, EP_IntValue)
-               || p->pRight->u.zToken==0 || p->pRight->u.zToken[0]!=0 );
+    p = sqlite3ExprSkipCollate(pEList->a[i].pExpr);
     if( (zName = pEList->a[i].zName)!=0 ){
       /* If the column contains an "AS <name>" phrase, use <name> as the name */
       zName = sqlite3DbStrDup(db, zName);
@@ -96901,6 +97835,9 @@ static int selectColumnsFromExprList(
     for(j=cnt=0; j<i; j++){
       if( sqlite3StrICmp(aCol[j].zName, zName)==0 ){
         char *zNewName;
+        int k;
+        for(k=nName-1; k>1 && sqlite3Isdigit(zName[k]); k--){}
+        if( zName[k]==':' ) nName = k;
         zName[nName] = 0;
         zNewName = sqlite3MPrintf(db, "%s:%d", zName, ++cnt);
         sqlite3DbFree(db, zName);
@@ -97048,7 +97985,7 @@ static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){
 
   /* 
   ** "LIMIT -1" always shows all rows.  There is some
-  ** contraversy about what the correct behavior should be.
+  ** controversy about what the correct behavior should be.
   ** The current implementation interprets "LIMIT 0" to mean
   ** no rows.
   */
@@ -97063,8 +98000,8 @@ static void computeLimitRegisters(Parse *pParse, Select *p, int iBreak){
       VdbeComment((v, "LIMIT counter"));
       if( n==0 ){
         sqlite3VdbeAddOp2(v, OP_Goto, 0, iBreak);
-      }else{
-        if( p->nSelectRow > (double)n ) p->nSelectRow = (double)n;
+      }else if( n>=0 && p->nSelectRow>(u64)n ){
+        p->nSelectRow = n;
       }
     }else{
       sqlite3ExprCode(pParse, p->pLimit, iLimit);
@@ -97199,7 +98136,7 @@ static int multiSelect(
   */
   if( dest.eDest==SRT_EphemTab ){
     assert( p->pEList );
-    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iParm, p->pEList->nExpr);
+    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iSDParm, p->pEList->nExpr);
     sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
     dest.eDest = SRT_Table;
   }
@@ -97232,6 +98169,8 @@ static int multiSelect(
       int addr = 0;
       int nLimit;
       assert( !pPrior->pLimit );
+      pPrior->iLimit = p->iLimit;
+      pPrior->iOffset = p->iOffset;
       pPrior->pLimit = p->pLimit;
       pPrior->pOffset = p->pOffset;
       explainSetInteger(iSub1, pParse->iNextSelectId);
@@ -97256,9 +98195,9 @@ static int multiSelect(
       p->nSelectRow += pPrior->nSelectRow;
       if( pPrior->pLimit
        && sqlite3ExprIsInteger(pPrior->pLimit, &nLimit)
-       && p->nSelectRow > (double)nLimit 
+       && nLimit>0 && p->nSelectRow > (u64)nLimit 
       ){
-        p->nSelectRow = (double)nLimit;
+        p->nSelectRow = nLimit;
       }
       if( addr ){
         sqlite3VdbeJumpHere(v, addr);
@@ -97285,7 +98224,7 @@ static int multiSelect(
                                      ** of a 3-way or more compound */
         assert( p->pLimit==0 );      /* Not allowed on leftward elements */
         assert( p->pOffset==0 );     /* Not allowed on leftward elements */
-        unionTab = dest.iParm;
+        unionTab = dest.iSDParm;
       }else{
         /* We will need to create our own temporary table to hold the
         ** intermediate results.
@@ -97342,7 +98281,7 @@ static int multiSelect(
       /* Convert the data in the temporary table into whatever form
       ** it is that we currently need.
       */
-      assert( unionTab==dest.iParm || dest.eDest!=priorOp );
+      assert( unionTab==dest.iSDParm || dest.eDest!=priorOp );
       if( dest.eDest!=priorOp ){
         int iCont, iBreak, iStart;
         assert( p->pEList );
@@ -97357,7 +98296,7 @@ static int multiSelect(
         sqlite3VdbeAddOp2(v, OP_Rewind, unionTab, iBreak);
         iStart = sqlite3VdbeCurrentAddr(v);
         selectInnerLoop(pParse, p, p->pEList, unionTab, p->pEList->nExpr,
-                        0, -1, &dest, iCont, iBreak);
+                        0, 0, &dest, iCont, iBreak);
         sqlite3VdbeResolveLabel(v, iCont);
         sqlite3VdbeAddOp2(v, OP_Next, unionTab, iStart);
         sqlite3VdbeResolveLabel(v, iBreak);
@@ -97406,7 +98345,7 @@ static int multiSelect(
       p->pLimit = 0;
       pOffset = p->pOffset;
       p->pOffset = 0;
-      intersectdest.iParm = tab2;
+      intersectdest.iSDParm = tab2;
       explainSetInteger(iSub2, pParse->iNextSelectId);
       rc = sqlite3Select(pParse, p, &intersectdest);
       testcase( rc!=SQLITE_OK );
@@ -97435,7 +98374,7 @@ static int multiSelect(
       sqlite3VdbeAddOp4Int(v, OP_NotFound, tab2, iCont, r1, 0);
       sqlite3ReleaseTempReg(pParse, r1);
       selectInnerLoop(pParse, p, p->pEList, tab1, p->pEList->nExpr,
-                      0, -1, &dest, iCont, iBreak);
+                      0, 0, &dest, iCont, iBreak);
       sqlite3VdbeResolveLabel(v, iCont);
       sqlite3VdbeAddOp2(v, OP_Next, tab1, iStart);
       sqlite3VdbeResolveLabel(v, iBreak);
@@ -97465,16 +98404,11 @@ static int multiSelect(
 
     assert( p->pRightmost==p );
     nCol = p->pEList->nExpr;
-    pKeyInfo = sqlite3DbMallocZero(db,
-                       sizeof(*pKeyInfo)+nCol*(sizeof(CollSeq*) + 1));
+    pKeyInfo = sqlite3KeyInfoAlloc(db, nCol);
     if( !pKeyInfo ){
       rc = SQLITE_NOMEM;
       goto multi_select_end;
     }
-
-    pKeyInfo->enc = ENC(db);
-    pKeyInfo->nField = (u16)nCol;
-
     for(i=0, apColl=pKeyInfo->aColl; i<nCol; i++, apColl++){
       *apColl = multiSelectCollSeq(pParse, p, i);
       if( 0==*apColl ){
@@ -97500,8 +98434,8 @@ static int multiSelect(
   }
 
 multi_select_end:
-  pDest->iMem = dest.iMem;
-  pDest->nMem = dest.nMem;
+  pDest->iSdst = dest.iSdst;
+  pDest->nSdst = dest.nSdst;
   sqlite3SelectDelete(db, pDelete);
   return rc;
 }
@@ -97511,8 +98445,8 @@ multi_select_end:
 ** Code an output subroutine for a coroutine implementation of a
 ** SELECT statment.
 **
-** The data to be output is contained in pIn->iMem.  There are
-** pIn->nMem columns to be output.  pDest is where the output should
+** The data to be output is contained in pIn->iSdst.  There are
+** pIn->nSdst columns to be output.  pDest is where the output should
 ** be sent.
 **
 ** regReturn is the number of the register holding the subroutine
@@ -97550,16 +98484,16 @@ static int generateOutputSubroutine(
   if( regPrev ){
     int j1, j2;
     j1 = sqlite3VdbeAddOp1(v, OP_IfNot, regPrev);
-    j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iMem, regPrev+1, pIn->nMem,
+    j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iSdst, regPrev+1, pIn->nSdst,
                               (char*)pKeyInfo, p4type);
     sqlite3VdbeAddOp3(v, OP_Jump, j2+2, iContinue, j2+2);
     sqlite3VdbeJumpHere(v, j1);
-    sqlite3ExprCodeCopy(pParse, pIn->iMem, regPrev+1, pIn->nMem);
+    sqlite3VdbeAddOp3(v, OP_Copy, pIn->iSdst, regPrev+1, pIn->nSdst-1);
     sqlite3VdbeAddOp2(v, OP_Integer, 1, regPrev);
   }
   if( pParse->db->mallocFailed ) return 0;
 
-  /* Suppress the the first OFFSET entries if there is an OFFSET clause
+  /* Suppress the first OFFSET entries if there is an OFFSET clause
   */
   codeOffset(v, p, iContinue);
 
@@ -97572,9 +98506,9 @@ static int generateOutputSubroutine(
       int r2 = sqlite3GetTempReg(pParse);
       testcase( pDest->eDest==SRT_Table );
       testcase( pDest->eDest==SRT_EphemTab );
-      sqlite3VdbeAddOp3(v, OP_MakeRecord, pIn->iMem, pIn->nMem, r1);
-      sqlite3VdbeAddOp2(v, OP_NewRowid, pDest->iParm, r2);
-      sqlite3VdbeAddOp3(v, OP_Insert, pDest->iParm, r1, r2);
+      sqlite3VdbeAddOp3(v, OP_MakeRecord, pIn->iSdst, pIn->nSdst, r1);
+      sqlite3VdbeAddOp2(v, OP_NewRowid, pDest->iSDParm, r2);
+      sqlite3VdbeAddOp3(v, OP_Insert, pDest->iSDParm, r1, r2);
       sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
       sqlite3ReleaseTempReg(pParse, r2);
       sqlite3ReleaseTempReg(pParse, r1);
@@ -97588,13 +98522,13 @@ static int generateOutputSubroutine(
     */
     case SRT_Set: {
       int r1;
-      assert( pIn->nMem==1 );
-      p->affinity = 
-         sqlite3CompareAffinity(p->pEList->a[0].pExpr, pDest->affinity);
+      assert( pIn->nSdst==1 );
+      pDest->affSdst = 
+         sqlite3CompareAffinity(p->pEList->a[0].pExpr, pDest->affSdst);
       r1 = sqlite3GetTempReg(pParse);
-      sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iMem, 1, r1, &p->affinity, 1);
-      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, 1);
-      sqlite3VdbeAddOp2(v, OP_IdxInsert, pDest->iParm, r1);
+      sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iSdst, 1, r1, &pDest->affSdst,1);
+      sqlite3ExprCacheAffinityChange(pParse, pIn->iSdst, 1);
+      sqlite3VdbeAddOp2(v, OP_IdxInsert, pDest->iSDParm, r1);
       sqlite3ReleaseTempReg(pParse, r1);
       break;
     }
@@ -97603,7 +98537,7 @@ static int generateOutputSubroutine(
     /* If any row exist in the result set, record that fact and abort.
     */
     case SRT_Exists: {
-      sqlite3VdbeAddOp2(v, OP_Integer, 1, pDest->iParm);
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, pDest->iSDParm);
       /* The LIMIT clause will terminate the loop for us */
       break;
     }
@@ -97614,23 +98548,23 @@ static int generateOutputSubroutine(
     ** of the scan loop.
     */
     case SRT_Mem: {
-      assert( pIn->nMem==1 );
-      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iParm, 1);
+      assert( pIn->nSdst==1 );
+      sqlite3ExprCodeMove(pParse, pIn->iSdst, pDest->iSDParm, 1);
       /* The LIMIT clause will jump out of the loop for us */
       break;
     }
 #endif /* #ifndef SQLITE_OMIT_SUBQUERY */
 
     /* The results are stored in a sequence of registers
-    ** starting at pDest->iMem.  Then the co-routine yields.
+    ** starting at pDest->iSdst.  Then the co-routine yields.
     */
     case SRT_Coroutine: {
-      if( pDest->iMem==0 ){
-        pDest->iMem = sqlite3GetTempRange(pParse, pIn->nMem);
-        pDest->nMem = pIn->nMem;
+      if( pDest->iSdst==0 ){
+        pDest->iSdst = sqlite3GetTempRange(pParse, pIn->nSdst);
+        pDest->nSdst = pIn->nSdst;
       }
-      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iMem, pDest->nMem);
-      sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
+      sqlite3ExprCodeMove(pParse, pIn->iSdst, pDest->iSdst, pDest->nSdst);
+      sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
       break;
     }
 
@@ -97644,8 +98578,8 @@ static int generateOutputSubroutine(
     */
     default: {
       assert( pDest->eDest==SRT_Output );
-      sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iMem, pIn->nMem);
-      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, pIn->nMem);
+      sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iSdst, pIn->nSdst);
+      sqlite3ExprCacheAffinityChange(pParse, pIn->iSdst, pIn->nSdst);
       break;
     }
   }
@@ -97849,21 +98783,18 @@ static int multiSelectOrderBy(
       assert( pItem->iOrderByCol>0  && pItem->iOrderByCol<=p->pEList->nExpr );
       aPermute[i] = pItem->iOrderByCol - 1;
     }
-    pKeyMerge =
-      sqlite3DbMallocRaw(db, sizeof(*pKeyMerge)+nOrderBy*(sizeof(CollSeq*)+1));
+    pKeyMerge = sqlite3KeyInfoAlloc(db, nOrderBy);
     if( pKeyMerge ){
-      pKeyMerge->aSortOrder = (u8*)&pKeyMerge->aColl[nOrderBy];
-      pKeyMerge->nField = (u16)nOrderBy;
-      pKeyMerge->enc = ENC(db);
       for(i=0; i<nOrderBy; i++){
         CollSeq *pColl;
         Expr *pTerm = pOrderBy->a[i].pExpr;
-        if( pTerm->flags & EP_ExpCollate ){
-          pColl = pTerm->pColl;
+        if( pTerm->flags & EP_Collate ){
+          pColl = sqlite3ExprCollSeq(pParse, pTerm);
         }else{
           pColl = multiSelectCollSeq(pParse, p, aPermute[i]);
-          pTerm->flags |= EP_ExpCollate;
-          pTerm->pColl = pColl;
+          if( pColl==0 ) pColl = db->pDfltColl;
+          pOrderBy->a[i].pExpr =
+             sqlite3ExprAddCollateString(pParse, pTerm, pColl->zName);
         }
         pKeyMerge->aColl[i] = pColl;
         pKeyMerge->aSortOrder[i] = pOrderBy->a[i].sortOrder;
@@ -97887,14 +98818,11 @@ static int multiSelectOrderBy(
   }else{
     int nExpr = p->pEList->nExpr;
     assert( nOrderBy>=nExpr || db->mallocFailed );
-    regPrev = sqlite3GetTempRange(pParse, nExpr+1);
+    regPrev = pParse->nMem+1;
+    pParse->nMem += nExpr+1;
     sqlite3VdbeAddOp2(v, OP_Integer, 0, regPrev);
-    pKeyDup = sqlite3DbMallocZero(db,
-                  sizeof(*pKeyDup) + nExpr*(sizeof(CollSeq*)+1) );
+    pKeyDup = sqlite3KeyInfoAlloc(db, nExpr);
     if( pKeyDup ){
-      pKeyDup->aSortOrder = (u8*)&pKeyDup->aColl[nExpr];
-      pKeyDup->nField = (u16)nExpr;
-      pKeyDup->enc = ENC(db);
       for(i=0; i<nExpr; i++){
         pKeyDup->aColl[i] = multiSelectCollSeq(pParse, p, i);
         pKeyDup->aSortOrder[i] = 0;
@@ -98064,16 +98992,11 @@ static int multiSelectOrderBy(
   */
   sqlite3VdbeResolveLabel(v, labelCmpr);
   sqlite3VdbeAddOp4(v, OP_Permutation, 0, 0, 0, (char*)aPermute, P4_INTARRAY);
-  sqlite3VdbeAddOp4(v, OP_Compare, destA.iMem, destB.iMem, nOrderBy,
+  sqlite3VdbeAddOp4(v, OP_Compare, destA.iSdst, destB.iSdst, nOrderBy,
                          (char*)pKeyMerge, P4_KEYINFO_HANDOFF);
+  sqlite3VdbeChangeP5(v, OPFLAG_PERMUTE);
   sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);
 
-  /* Release temporary registers
-  */
-  if( regPrev ){
-    sqlite3ReleaseTempRange(pParse, regPrev, nOrderBy+1);
-  }
-
   /* Jump to the this point in order to terminate the query.
   */
   sqlite3VdbeResolveLabel(v, labelEnd);
@@ -98133,9 +99056,6 @@ static Expr *substExpr(
       assert( pEList!=0 && pExpr->iColumn<pEList->nExpr );
       assert( pExpr->pLeft==0 && pExpr->pRight==0 );
       pNew = sqlite3ExprDup(db, pEList->a[pExpr->iColumn].pExpr, 0);
-      if( pNew && pExpr->pColl ){
-        pNew->pColl = pExpr->pColl;
-      }
       sqlite3ExprDelete(db, pExpr);
       pExpr = pNew;
     }
@@ -98278,6 +99198,12 @@ static void substSelect(
 **        operators have an implied DISTINCT which is disallowed by
 **        restriction (4).
 **
+**        Also, each component of the sub-query must return the same number
+**        of result columns. This is actually a requirement for any compound
+**        SELECT statement, but all the code here does is make sure that no
+**        such (illegal) sub-query is flattened. The caller will detect the
+**        syntax error and return a detailed message.
+**
 **  (18)  If the sub-query is a compound select, then all terms of the
 **        ORDER by clause of the parent must be simple references to 
 **        columns of the sub-query.
@@ -98328,7 +99254,7 @@ static int flattenSubquery(
   */
   assert( p!=0 );
   assert( p->pPrior==0 );  /* Unable to flatten compound queries */
-  if( db->flags & SQLITE_QueryFlattener ) return 0;
+  if( OptimizationDisabled(db, SQLITE_QueryFlattener) ) return 0;
   pSrc = p->pSrc;
   assert( pSrc && iFrom>=0 && iFrom<pSrc->nSrc );
   pSubitem = &pSrc->a[iFrom];
@@ -98421,6 +99347,7 @@ static int flattenSubquery(
       if( (pSub1->selFlags & (SF_Distinct|SF_Aggregate))!=0
        || (pSub1->pPrior && pSub1->op!=TK_ALL) 
        || pSub1->pSrc->nSrc<1
+       || pSub->pEList->nExpr!=pSub1->pEList->nExpr
       ){
         return 0;
       }
@@ -98481,12 +99408,15 @@ static int flattenSubquery(
     Select *pNew;
     ExprList *pOrderBy = p->pOrderBy;
     Expr *pLimit = p->pLimit;
+    Expr *pOffset = p->pOffset;
     Select *pPrior = p->pPrior;
     p->pOrderBy = 0;
     p->pSrc = 0;
     p->pPrior = 0;
     p->pLimit = 0;
+    p->pOffset = 0;
     pNew = sqlite3SelectDup(db, p, 0);
+    p->pOffset = pOffset;
     p->pLimit = pLimit;
     p->pOrderBy = pOrderBy;
     p->pSrc = pSrc;
@@ -98616,10 +99546,9 @@ static int flattenSubquery(
     pList = pParent->pEList;
     for(i=0; i<pList->nExpr; i++){
       if( pList->a[i].zName==0 ){
-        const char *zSpan = pList->a[i].zSpan;
-        if( ALWAYS(zSpan) ){
-          pList->a[i].zName = sqlite3DbStrDup(db, zSpan);
-        }
+        char *zName = sqlite3DbStrDup(db, pList->a[i].zSpan);
+        sqlite3Dequote(zName);
+        pList->a[i].zName = zName;
       }
     }
     substExprList(db, pParent->pEList, iParent, pSub->pEList);
@@ -98680,34 +99609,43 @@ static int flattenSubquery(
 #endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
 
 /*
-** Analyze the SELECT statement passed as an argument to see if it
-** is a min() or max() query. Return WHERE_ORDERBY_MIN or WHERE_ORDERBY_MAX if 
-** it is, or 0 otherwise. At present, a query is considered to be
-** a min()/max() query if:
+** Based on the contents of the AggInfo structure indicated by the first
+** argument, this function checks if the following are true:
 **
-**   1. There is a single object in the FROM clause.
+**    * the query contains just a single aggregate function,
+**    * the aggregate function is either min() or max(), and
+**    * the argument to the aggregate function is a column value.
 **
-**   2. There is a single expression in the result set, and it is
-**      either min(x) or max(x), where x is a column reference.
+** If all of the above are true, then WHERE_ORDERBY_MIN or WHERE_ORDERBY_MAX
+** is returned as appropriate. Also, *ppMinMax is set to point to the 
+** list of arguments passed to the aggregate before returning.
+**
+** Or, if the conditions above are not met, *ppMinMax is set to 0 and
+** WHERE_ORDERBY_NORMAL is returned.
 */
-static u8 minMaxQuery(Select *p){
-  Expr *pExpr;
-  ExprList *pEList = p->pEList;
+static u8 minMaxQuery(AggInfo *pAggInfo, ExprList **ppMinMax){
+  int eRet = WHERE_ORDERBY_NORMAL;          /* Return value */
 
-  if( pEList->nExpr!=1 ) return WHERE_ORDERBY_NORMAL;
-  pExpr = pEList->a[0].pExpr;
-  if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
-  if( NEVER(ExprHasProperty(pExpr, EP_xIsSelect)) ) return 0;
-  pEList = pExpr->x.pList;
-  if( pEList==0 || pEList->nExpr!=1 ) return 0;
-  if( pEList->a[0].pExpr->op!=TK_AGG_COLUMN ) return WHERE_ORDERBY_NORMAL;
-  assert( !ExprHasProperty(pExpr, EP_IntValue) );
-  if( sqlite3StrICmp(pExpr->u.zToken,"min")==0 ){
-    return WHERE_ORDERBY_MIN;
-  }else if( sqlite3StrICmp(pExpr->u.zToken,"max")==0 ){
-    return WHERE_ORDERBY_MAX;
+  *ppMinMax = 0;
+  if( pAggInfo->nFunc==1 ){
+    Expr *pExpr = pAggInfo->aFunc[0].pExpr; /* Aggregate function */
+    ExprList *pEList = pExpr->x.pList;      /* Arguments to agg function */
+
+    assert( pExpr->op==TK_AGG_FUNCTION );
+    if( pEList && pEList->nExpr==1 && pEList->a[0].pExpr->op==TK_AGG_COLUMN ){
+      const char *zFunc = pExpr->u.zToken;
+      if( sqlite3StrICmp(zFunc, "min")==0 ){
+        eRet = WHERE_ORDERBY_MIN;
+        *ppMinMax = pEList;
+      }else if( sqlite3StrICmp(zFunc, "max")==0 ){
+        eRet = WHERE_ORDERBY_MAX;
+        *ppMinMax = pEList;
+      }
+    }
   }
-  return WHERE_ORDERBY_NORMAL;
+
+  assert( *ppMinMax==0 || (*ppMinMax)->nExpr==1 );
+  return eRet;
 }
 
 /*
@@ -98738,7 +99676,7 @@ static Table *isSimpleCount(Select *p, AggInfo *pAggInfo){
 
   if( IsVirtual(pTab) ) return 0;
   if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
-  if( pAggInfo->nFunc==0 ) return 0;
+  if( NEVER(pAggInfo->nFunc==0) ) return 0;
   if( (pAggInfo->aFunc[0].pFunc->flags&SQLITE_FUNC_COUNT)==0 ) return 0;
   if( pExpr->flags&EP_Distinct ) return 0;
 
@@ -98770,6 +99708,69 @@ SQLITE_PRIVATE int sqlite3IndexedByLookup(Parse *pParse, struct SrcList_item *pF
   }
   return SQLITE_OK;
 }
+/*
+** Detect compound SELECT statements that use an ORDER BY clause with 
+** an alternative collating sequence.
+**
+**    SELECT ... FROM t1 EXCEPT SELECT ... FROM t2 ORDER BY .. COLLATE ...
+**
+** These are rewritten as a subquery:
+**
+**    SELECT * FROM (SELECT ... FROM t1 EXCEPT SELECT ... FROM t2)
+**     ORDER BY ... COLLATE ...
+**
+** This transformation is necessary because the multiSelectOrderBy() routine
+** above that generates the code for a compound SELECT with an ORDER BY clause
+** uses a merge algorithm that requires the same collating sequence on the
+** result columns as on the ORDER BY clause.  See ticket
+** http://www.sqlite.org/src/info/6709574d2a
+**
+** This transformation is only needed for EXCEPT, INTERSECT, and UNION.
+** The UNION ALL operator works fine with multiSelectOrderBy() even when
+** there are COLLATE terms in the ORDER BY.
+*/
+static int convertCompoundSelectToSubquery(Walker *pWalker, Select *p){
+  int i;
+  Select *pNew;
+  Select *pX;
+  sqlite3 *db;
+  struct ExprList_item *a;
+  SrcList *pNewSrc;
+  Parse *pParse;
+  Token dummy;
+
+  if( p->pPrior==0 ) return WRC_Continue;
+  if( p->pOrderBy==0 ) return WRC_Continue;
+  for(pX=p; pX && (pX->op==TK_ALL || pX->op==TK_SELECT); pX=pX->pPrior){}
+  if( pX==0 ) return WRC_Continue;
+  a = p->pOrderBy->a;
+  for(i=p->pOrderBy->nExpr-1; i>=0; i--){
+    if( a[i].pExpr->flags & EP_Collate ) break;
+  }
+  if( i<0 ) return WRC_Continue;
+
+  /* If we reach this point, that means the transformation is required. */
+
+  pParse = pWalker->pParse;
+  db = pParse->db;
+  pNew = sqlite3DbMallocZero(db, sizeof(*pNew) );
+  if( pNew==0 ) return WRC_Abort;
+  memset(&dummy, 0, sizeof(dummy));
+  pNewSrc = sqlite3SrcListAppendFromTerm(pParse,0,0,0,&dummy,pNew,0,0);
+  if( pNewSrc==0 ) return WRC_Abort;
+  *pNew = *p;
+  p->pSrc = pNewSrc;
+  p->pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db, TK_ALL, 0));
+  p->op = TK_SELECT;
+  p->pWhere = 0;
+  pNew->pGroupBy = 0;
+  pNew->pHaving = 0;
+  pNew->pOrderBy = 0;
+  p->pPrior = 0;
+  pNew->pLimit = 0;
+  pNew->pOffset = 0;
+  return WRC_Continue;
+}
 
 /*
 ** This routine is a Walker callback for "expanding" a SELECT statement.
@@ -98802,14 +99803,16 @@ static int selectExpander(Walker *pWalker, Select *p){
   ExprList *pEList;
   struct SrcList_item *pFrom;
   sqlite3 *db = pParse->db;
+  Expr *pE, *pRight, *pExpr;
+  u16 selFlags = p->selFlags;
 
+  p->selFlags |= SF_Expanded;
   if( db->mallocFailed  ){
     return WRC_Abort;
   }
-  if( NEVER(p->pSrc==0) || (p->selFlags & SF_Expanded)!=0 ){
+  if( NEVER(p->pSrc==0) || (selFlags & SF_Expanded)!=0 ){
     return WRC_Prune;
   }
-  p->selFlags |= SF_Expanded;
   pTabList = p->pSrc;
   pEList = p->pEList;
 
@@ -98850,9 +99853,14 @@ static int selectExpander(Walker *pWalker, Select *p){
     }else{
       /* An ordinary table or view name in the FROM clause */
       assert( pFrom->pTab==0 );
-      pFrom->pTab = pTab = 
-        sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase);
+      pFrom->pTab = pTab = sqlite3LocateTableItem(pParse, 0, pFrom);
       if( pTab==0 ) return WRC_Abort;
+      if( pTab->nRef==0xffff ){
+        sqlite3ErrorMsg(pParse, "too many references to \"%s\": max 65535",
+           pTab->zName);
+        pFrom->pTab = 0;
+        return WRC_Abort;
+      }
       pTab->nRef++;
 #if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
       if( pTab->pSelect || IsVirtual(pTab) ){
@@ -98888,7 +99896,7 @@ static int selectExpander(Walker *pWalker, Select *p){
   ** that need expanding.
   */
   for(k=0; k<pEList->nExpr; k++){
-    Expr *pE = pEList->a[k].pExpr;
+    pE = pEList->a[k].pExpr;
     if( pE->op==TK_ALL ) break;
     assert( pE->op!=TK_DOT || pE->pRight!=0 );
     assert( pE->op!=TK_DOT || (pE->pLeft!=0 && pE->pLeft->op==TK_ID) );
@@ -98906,10 +99914,18 @@ static int selectExpander(Walker *pWalker, Select *p){
     int longNames = (flags & SQLITE_FullColNames)!=0
                       && (flags & SQLITE_ShortColNames)==0;
 
+    /* When processing FROM-clause subqueries, it is always the case
+    ** that full_column_names=OFF and short_column_names=ON.  The
+    ** sqlite3ResultSetOfSelect() routine makes it so. */
+    assert( (p->selFlags & SF_NestedFrom)==0
+          || ((flags & SQLITE_FullColNames)==0 &&
+              (flags & SQLITE_ShortColNames)!=0) );
+
     for(k=0; k<pEList->nExpr; k++){
-      Expr *pE = a[k].pExpr;
-      assert( pE->op!=TK_DOT || pE->pRight!=0 );
-      if( pE->op!=TK_ALL && (pE->op!=TK_DOT || pE->pRight->op!=TK_ALL) ){
+      pE = a[k].pExpr;
+      pRight = pE->pRight;
+      assert( pE->op!=TK_DOT || pRight!=0 );
+      if( pE->op!=TK_ALL && (pE->op!=TK_DOT || pRight->op!=TK_ALL) ){
         /* This particular expression does not need to be expanded.
         */
         pNew = sqlite3ExprListAppend(pParse, pNew, a[k].pExpr);
@@ -98924,32 +99940,43 @@ static int selectExpander(Walker *pWalker, Select *p){
         /* This expression is a "*" or a "TABLE.*" and needs to be
         ** expanded. */
         int tableSeen = 0;      /* Set to 1 when TABLE matches */
-        char *zTName;            /* text of name of TABLE */
+        char *zTName = 0;       /* text of name of TABLE */
         if( pE->op==TK_DOT ){
           assert( pE->pLeft!=0 );
           assert( !ExprHasProperty(pE->pLeft, EP_IntValue) );
           zTName = pE->pLeft->u.zToken;
-        }else{
-          zTName = 0;
         }
         for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
           Table *pTab = pFrom->pTab;
+          Select *pSub = pFrom->pSelect;
           char *zTabName = pFrom->zAlias;
+          const char *zSchemaName = 0;
+          int iDb;
           if( zTabName==0 ){
             zTabName = pTab->zName;
           }
           if( db->mallocFailed ) break;
-          if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){
-            continue;
+          if( pSub==0 || (pSub->selFlags & SF_NestedFrom)==0 ){
+            pSub = 0;
+            if( zTName && sqlite3StrICmp(zTName, zTabName)!=0 ){
+              continue;
+            }
+            iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+            zSchemaName = iDb>=0 ? db->aDb[iDb].zName : "*";
           }
-          tableSeen = 1;
           for(j=0; j<pTab->nCol; j++){
-            Expr *pExpr, *pRight;
             char *zName = pTab->aCol[j].zName;
             char *zColname;  /* The computed column name */
             char *zToFree;   /* Malloced string that needs to be freed */
             Token sColname;  /* Computed column name as a token */
 
+            assert( zName );
+            if( zTName && pSub
+             && sqlite3MatchSpanName(pSub->pEList->a[j].zSpan, 0, zTName, 0)==0
+            ){
+              continue;
+            }
+
             /* If a column is marked as 'hidden' (currently only possible
             ** for virtual tables), do not include it in the expanded
             ** result-set list.
@@ -98958,6 +99985,7 @@ static int selectExpander(Walker *pWalker, Select *p){
               assert(IsVirtual(pTab));
               continue;
             }
+            tableSeen = 1;
 
             if( i>0 && zTName==0 ){
               if( (pFrom->jointype & JT_NATURAL)!=0
@@ -98980,6 +100008,10 @@ static int selectExpander(Walker *pWalker, Select *p){
               Expr *pLeft;
               pLeft = sqlite3Expr(db, TK_ID, zTabName);
               pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pRight, 0);
+              if( zSchemaName ){
+                pLeft = sqlite3Expr(db, TK_ID, zSchemaName);
+                pExpr = sqlite3PExpr(pParse, TK_DOT, pLeft, pExpr, 0);
+              }
               if( longNames ){
                 zColname = sqlite3MPrintf(db, "%s.%s", zTabName, zName);
                 zToFree = zColname;
@@ -98991,6 +100023,18 @@ static int selectExpander(Walker *pWalker, Select *p){
             sColname.z = zColname;
             sColname.n = sqlite3Strlen30(zColname);
             sqlite3ExprListSetName(pParse, pNew, &sColname, 0);
+            if( pNew && (p->selFlags & SF_NestedFrom)!=0 ){
+              struct ExprList_item *pX = &pNew->a[pNew->nExpr-1];
+              if( pSub ){
+                pX->zSpan = sqlite3DbStrDup(db, pSub->pEList->a[j].zSpan);
+                testcase( pX->zSpan==0 );
+              }else{
+                pX->zSpan = sqlite3MPrintf(db, "%s.%s.%s",
+                                           zSchemaName, zTabName, zColname);
+                testcase( pX->zSpan==0 );
+              }
+              pX->bSpanIsTab = 1;
+            }
             sqlite3DbFree(db, zToFree);
           }
         }
@@ -99043,9 +100087,14 @@ static int exprWalkNoop(Walker *NotUsed, Expr *NotUsed2){
 */
 static void sqlite3SelectExpand(Parse *pParse, Select *pSelect){
   Walker w;
-  w.xSelectCallback = selectExpander;
+  memset(&w, 0, sizeof(w));
   w.xExprCallback = exprWalkNoop;
   w.pParse = pParse;
+  if( pParse->hasCompound ){
+    w.xSelectCallback = convertCompoundSelectToSubquery;
+    sqlite3WalkSelect(&w, pSelect);
+  }
+  w.xSelectCallback = selectExpander;
   sqlite3WalkSelect(&w, pSelect);
 }
 
@@ -99101,16 +100150,18 @@ static int selectAddSubqueryTypeInfo(Walker *pWalker, Select *p){
 static void sqlite3SelectAddTypeInfo(Parse *pParse, Select *pSelect){
 #ifndef SQLITE_OMIT_SUBQUERY
   Walker w;
+  memset(&w, 0, sizeof(w));
   w.xSelectCallback = selectAddSubqueryTypeInfo;
   w.xExprCallback = exprWalkNoop;
   w.pParse = pParse;
+  w.bSelectDepthFirst = 1;
   sqlite3WalkSelect(&w, pSelect);
 #endif
 }
 
 
 /*
-** This routine sets of a SELECT statement for processing.  The
+** This routine sets up a SELECT statement for processing.  The
 ** following is accomplished:
 **
 **     *  VDBE Cursor numbers are assigned to all FROM-clause terms.
@@ -99129,6 +100180,7 @@ SQLITE_PRIVATE void sqlite3SelectPrep(
   sqlite3 *db;
   if( NEVER(p==0) ) return;
   db = pParse->db;
+  if( db->mallocFailed ) return;
   if( p->selFlags & SF_HasTypeInfo ) return;
   sqlite3SelectExpand(pParse, p);
   if( pParse->nErr || db->mallocFailed ) return;
@@ -99142,7 +100194,8 @@ SQLITE_PRIVATE void sqlite3SelectPrep(
 **
 ** The aggregate accumulator is a set of memory cells that hold
 ** intermediate results while calculating an aggregate.  This
-** routine simply stores NULLs in all of those memory cells.
+** routine generates code that stores NULLs in all of those memory
+** cells.
 */
 static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
   Vdbe *v = pParse->pVdbe;
@@ -99281,11 +100334,10 @@ static void explainSimpleCount(
   Index *pIdx                     /* Index used to optimize scan, or NULL */
 ){
   if( pParse->explain==2 ){
-    char *zEqp = sqlite3MPrintf(pParse->db, "SCAN TABLE %s %s%s(~%d rows)",
+    char *zEqp = sqlite3MPrintf(pParse->db, "SCAN TABLE %s%s%s",
         pTab->zName, 
-        pIdx ? "USING COVERING INDEX " : "",
-        pIdx ? pIdx->zName : "",
-        pTab->nRowEst
+        pIdx ? " USING COVERING INDEX " : "",
+        pIdx ? pIdx->zName : ""
     );
     sqlite3VdbeAddOp4(
         pParse->pVdbe, OP_Explain, pParse->iSelectId, 0, 0, zEqp, P4_DYNAMIC
@@ -99310,23 +100362,24 @@ static void explainSimpleCount(
 **
 **     SRT_Mem         Only valid if the result is a single column.
 **                     Store the first column of the first result row
-**                     in register pDest->iParm then abandon the rest
+**                     in register pDest->iSDParm then abandon the rest
 **                     of the query.  This destination implies "LIMIT 1".
 **
 **     SRT_Set         The result must be a single column.  Store each
-**                     row of result as the key in table pDest->iParm. 
-**                     Apply the affinity pDest->affinity before storing
+**                     row of result as the key in table pDest->iSDParm. 
+**                     Apply the affinity pDest->affSdst before storing
 **                     results.  Used to implement "IN (SELECT ...)".
 **
-**     SRT_Union       Store results as a key in a temporary table pDest->iParm.
+**     SRT_Union       Store results as a key in a temporary table 
+**                     identified by pDest->iSDParm.
 **
-**     SRT_Except      Remove results from the temporary table pDest->iParm.
+**     SRT_Except      Remove results from the temporary table pDest->iSDParm.
 **
-**     SRT_Table       Store results in temporary table pDest->iParm.
+**     SRT_Table       Store results in temporary table pDest->iSDParm.
 **                     This is like SRT_EphemTab except that the table
 **                     is assumed to already be open.
 **
-**     SRT_EphemTab    Create an temporary table pDest->iParm and store
+**     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
 **                     the result there. The cursor is left open after
 **                     returning.  This is like SRT_Table except that
 **                     this destination uses OP_OpenEphemeral to create
@@ -99334,9 +100387,9 @@ static void explainSimpleCount(
 **
 **     SRT_Coroutine   Generate a co-routine that returns a new row of
 **                     results each time it is invoked.  The entry point
-**                     of the co-routine is stored in register pDest->iParm.
+**                     of the co-routine is stored in register pDest->iSDParm.
 **
-**     SRT_Exists      Store a 1 in memory cell pDest->iParm if the result
+**     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
 **                     set is not empty.
 **
 **     SRT_Discard     Throw the results away.  This is used by SELECT
@@ -99365,11 +100418,9 @@ SQLITE_PRIVATE int sqlite3Select(
   ExprList *pOrderBy;    /* The ORDER BY clause.  May be NULL */
   ExprList *pGroupBy;    /* The GROUP BY clause.  May be NULL */
   Expr *pHaving;         /* The HAVING clause.  May be NULL */
-  int isDistinct;        /* True if the DISTINCT keyword is present */
-  int distinct;          /* Table to use for the distinct set */
   int rc = 1;            /* Value to return from this function */
   int addrSortIndex;     /* Address of an OP_OpenEphemeral instruction */
-  int addrDistinctIndex; /* Address of an OP_OpenEphemeral instruction */
+  DistinctCtx sDistinct; /* Info on how to code the DISTINCT keyword */
   AggInfo sAggInfo;      /* Information used by aggregate queries */
   int iEnd;              /* Address of the end of the query */
   sqlite3 *db;           /* The database connection */
@@ -99429,13 +100480,22 @@ SQLITE_PRIVATE int sqlite3Select(
     int isAggSub;
 
     if( pSub==0 ) continue;
+
+    /* Sometimes the code for a subquery will be generated more than
+    ** once, if the subquery is part of the WHERE clause in a LEFT JOIN,
+    ** for example.  In that case, do not regenerate the code to manifest
+    ** a view or the co-routine to implement a view.  The first instance
+    ** is sufficient, though the subroutine to manifest the view does need
+    ** to be invoked again. */
     if( pItem->addrFillSub ){
-      sqlite3VdbeAddOp2(v, OP_Gosub, pItem->regReturn, pItem->addrFillSub);
+      if( pItem->viaCoroutine==0 ){
+        sqlite3VdbeAddOp2(v, OP_Gosub, pItem->regReturn, pItem->addrFillSub);
+      }
       continue;
     }
 
     /* Increment Parse.nHeight by the height of the largest expression
-    ** tree refered to by this, the parent select. The child select
+    ** tree referred to by this, the parent select. The child select
     ** may contain expression trees of at most
     ** (SQLITE_MAX_EXPR_DEPTH-Parse.nHeight) height. This is a bit
     ** more conservative than necessary, but much easier than enforcing
@@ -99451,6 +100511,44 @@ SQLITE_PRIVATE int sqlite3Select(
         p->selFlags |= SF_Aggregate;
       }
       i = -1;
+    }else if( pTabList->nSrc==1 && (p->selFlags & SF_Materialize)==0
+      && OptimizationEnabled(db, SQLITE_SubqCoroutine)
+    ){
+      /* Implement a co-routine that will return a single row of the result
+      ** set on each invocation.
+      */
+      int addrTop;
+      int addrEof;
+      pItem->regReturn = ++pParse->nMem;
+      addrEof = ++pParse->nMem;
+      /* Before coding the OP_Goto to jump to the start of the main routine,
+      ** ensure that the jump to the verify-schema routine has already
+      ** been coded. Otherwise, the verify-schema would likely be coded as 
+      ** part of the co-routine. If the main routine then accessed the 
+      ** database before invoking the co-routine for the first time (for 
+      ** example to initialize a LIMIT register from a sub-select), it would 
+      ** be doing so without having verified the schema version and obtained 
+      ** the required db locks. See ticket d6b36be38.  */
+      sqlite3CodeVerifySchema(pParse, -1);
+      sqlite3VdbeAddOp0(v, OP_Goto);
+      addrTop = sqlite3VdbeAddOp1(v, OP_OpenPseudo, pItem->iCursor);
+      sqlite3VdbeChangeP5(v, 1);
+      VdbeComment((v, "coroutine for %s", pItem->pTab->zName));
+      pItem->addrFillSub = addrTop;
+      sqlite3VdbeAddOp2(v, OP_Integer, 0, addrEof);
+      sqlite3VdbeChangeP5(v, 1);
+      sqlite3SelectDestInit(&dest, SRT_Coroutine, pItem->regReturn);
+      explainSetInteger(pItem->iSelectId, (u8)pParse->iNextSelectId);
+      sqlite3Select(pParse, pSub, &dest);
+      pItem->pTab->nRowEst = (unsigned)pSub->nSelectRow;
+      pItem->viaCoroutine = 1;
+      sqlite3VdbeChangeP2(v, addrTop, dest.iSdst);
+      sqlite3VdbeChangeP3(v, addrTop, dest.nSdst);
+      sqlite3VdbeAddOp2(v, OP_Integer, 1, addrEof);
+      sqlite3VdbeAddOp1(v, OP_Yield, pItem->regReturn);
+      VdbeComment((v, "end %s", pItem->pTab->zName));
+      sqlite3VdbeJumpHere(v, addrTop-1);
+      sqlite3ClearTempRegCache(pParse);
     }else{
       /* Generate a subroutine that will fill an ephemeral table with
       ** the content of this subquery.  pItem->addrFillSub will point
@@ -99466,7 +100564,7 @@ SQLITE_PRIVATE int sqlite3Select(
       pItem->addrFillSub = topAddr+1;
       VdbeNoopComment((v, "materialize %s", pItem->pTab->zName));
       if( pItem->isCorrelated==0 ){
-        /* If the subquery is no correlated and if we are not inside of
+        /* If the subquery is not correlated and if we are not inside of
         ** a trigger, then we only need to compute the value of the subquery
         ** once. */
         onceAddr = sqlite3CodeOnce(pParse);
@@ -99495,7 +100593,7 @@ SQLITE_PRIVATE int sqlite3Select(
   pWhere = p->pWhere;
   pGroupBy = p->pGroupBy;
   pHaving = p->pHaving;
-  isDistinct = (p->selFlags & SF_Distinct)!=0;
+  sDistinct.isTnct = (p->selFlags & SF_Distinct)!=0;
 
 #ifndef SQLITE_OMIT_COMPOUND_SELECT
   /* If there is are a sequence of queries, do the earlier ones first.
@@ -99529,8 +100627,8 @@ SQLITE_PRIVATE int sqlite3Select(
   ** Use the SQLITE_GroupByOrder flag with SQLITE_TESTCTRL_OPTIMIZER
   ** to disable this optimization for testing purposes.
   */
-  if( sqlite3ExprListCompare(p->pGroupBy, pOrderBy)==0
-         && (db->flags & SQLITE_GroupByOrder)==0 ){
+  if( sqlite3ExprListCompare(p->pGroupBy, pOrderBy, -1)==0
+         && OptimizationEnabled(db, SQLITE_GroupByOrder) ){
     pOrderBy = 0;
   }
 
@@ -99550,12 +100648,16 @@ SQLITE_PRIVATE int sqlite3Select(
   ** BY and DISTINCT, and an index or separate temp-table for the other.
   */
   if( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct 
-   && sqlite3ExprListCompare(pOrderBy, p->pEList)==0
+   && sqlite3ExprListCompare(pOrderBy, p->pEList, -1)==0
   ){
     p->selFlags &= ~SF_Distinct;
     p->pGroupBy = sqlite3ExprListDup(db, p->pEList, 0);
     pGroupBy = p->pGroupBy;
     pOrderBy = 0;
+    /* Notice that even thought SF_Distinct has been cleared from p->selFlags,
+    ** the sDistinct.isTnct is still set.  Hence, isTnct represents the
+    ** original setting of the SF_Distinct flag, not the current setting */
+    assert( sDistinct.isTnct );
   }
 
   /* If there is an ORDER BY clause, then this sorting
@@ -99580,13 +100682,13 @@ SQLITE_PRIVATE int sqlite3Select(
   /* If the output is destined for a temporary table, open that table.
   */
   if( pDest->eDest==SRT_EphemTab ){
-    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iParm, pEList->nExpr);
+    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iSDParm, pEList->nExpr);
   }
 
   /* Set the limiter.
   */
   iEnd = sqlite3VdbeMakeLabel(v);
-  p->nSelectRow = (double)LARGEST_INT64;
+  p->nSelectRow = LARGEST_INT64;
   computeLimitRegisters(pParse, p, iEnd);
   if( p->iLimit==0 && addrSortIndex>=0 ){
     sqlite3VdbeGetOp(v, addrSortIndex)->opcode = OP_SorterOpen;
@@ -99596,24 +100698,32 @@ SQLITE_PRIVATE int sqlite3Select(
   /* Open a virtual index to use for the distinct set.
   */
   if( p->selFlags & SF_Distinct ){
-    KeyInfo *pKeyInfo;
-    distinct = pParse->nTab++;
-    pKeyInfo = keyInfoFromExprList(pParse, p->pEList);
-    addrDistinctIndex = sqlite3VdbeAddOp4(v, OP_OpenEphemeral, distinct, 0, 0,
-        (char*)pKeyInfo, P4_KEYINFO_HANDOFF);
+    sDistinct.tabTnct = pParse->nTab++;
+    sDistinct.addrTnct = sqlite3VdbeAddOp4(v, OP_OpenEphemeral,
+                                sDistinct.tabTnct, 0, 0,
+                                (char*)keyInfoFromExprList(pParse, p->pEList),
+                                P4_KEYINFO_HANDOFF);
     sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
+    sDistinct.eTnctType = WHERE_DISTINCT_UNORDERED;
   }else{
-    distinct = addrDistinctIndex = -1;
+    sDistinct.eTnctType = WHERE_DISTINCT_NOOP;
   }
 
-  /* Aggregate and non-aggregate queries are handled differently */
   if( !isAgg && pGroupBy==0 ){
-    ExprList *pDist = (isDistinct ? p->pEList : 0);
+    /* No aggregate functions and no GROUP BY clause */
+    u16 wctrlFlags = (sDistinct.isTnct ? WHERE_WANT_DISTINCT : 0);
 
     /* Begin the database scan. */
-    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pOrderBy, pDist, 0);
+    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pOrderBy, p->pEList,
+                               wctrlFlags, 0);
     if( pWInfo==0 ) goto select_end;
-    if( pWInfo->nRowOut < p->nSelectRow ) p->nSelectRow = pWInfo->nRowOut;
+    if( sqlite3WhereOutputRowCount(pWInfo) < p->nSelectRow ){
+      p->nSelectRow = sqlite3WhereOutputRowCount(pWInfo);
+    }
+    if( sDistinct.isTnct && sqlite3WhereIsDistinct(pWInfo) ){
+      sDistinct.eTnctType = sqlite3WhereIsDistinct(pWInfo);
+    }
+    if( pOrderBy && sqlite3WhereIsOrdered(pWInfo) ) pOrderBy = 0;
 
     /* If sorting index that was created by a prior OP_OpenEphemeral 
     ** instruction ended up not being needed, then change the OP_OpenEphemeral
@@ -99624,59 +100734,17 @@ SQLITE_PRIVATE int sqlite3Select(
       p->addrOpenEphm[2] = -1;
     }
 
-    if( pWInfo->eDistinct ){
-      VdbeOp *pOp;                /* No longer required OpenEphemeral instr. */
-     
-      assert( addrDistinctIndex>=0 );
-      pOp = sqlite3VdbeGetOp(v, addrDistinctIndex);
-
-      assert( isDistinct );
-      assert( pWInfo->eDistinct==WHERE_DISTINCT_ORDERED 
-           || pWInfo->eDistinct==WHERE_DISTINCT_UNIQUE 
-      );
-      distinct = -1;
-      if( pWInfo->eDistinct==WHERE_DISTINCT_ORDERED ){
-        int iJump;
-        int iExpr;
-        int iFlag = ++pParse->nMem;
-        int iBase = pParse->nMem+1;
-        int iBase2 = iBase + pEList->nExpr;
-        pParse->nMem += (pEList->nExpr*2);
-
-        /* Change the OP_OpenEphemeral coded earlier to an OP_Integer. The
-        ** OP_Integer initializes the "first row" flag.  */
-        pOp->opcode = OP_Integer;
-        pOp->p1 = 1;
-        pOp->p2 = iFlag;
-
-        sqlite3ExprCodeExprList(pParse, pEList, iBase, 1);
-        iJump = sqlite3VdbeCurrentAddr(v) + 1 + pEList->nExpr + 1 + 1;
-        sqlite3VdbeAddOp2(v, OP_If, iFlag, iJump-1);
-        for(iExpr=0; iExpr<pEList->nExpr; iExpr++){
-          CollSeq *pColl = sqlite3ExprCollSeq(pParse, pEList->a[iExpr].pExpr);
-          sqlite3VdbeAddOp3(v, OP_Ne, iBase+iExpr, iJump, iBase2+iExpr);
-          sqlite3VdbeChangeP4(v, -1, (const char *)pColl, P4_COLLSEQ);
-          sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
-        }
-        sqlite3VdbeAddOp2(v, OP_Goto, 0, pWInfo->iContinue);
-
-        sqlite3VdbeAddOp2(v, OP_Integer, 0, iFlag);
-        assert( sqlite3VdbeCurrentAddr(v)==iJump );
-        sqlite3VdbeAddOp3(v, OP_Move, iBase, iBase2, pEList->nExpr);
-      }else{
-        pOp->opcode = OP_Noop;
-      }
-    }
-
     /* Use the standard inner loop. */
-    selectInnerLoop(pParse, p, pEList, 0, 0, pOrderBy, distinct, pDest,
-                    pWInfo->iContinue, pWInfo->iBreak);
+    selectInnerLoop(pParse, p, pEList, 0, 0, pOrderBy, &sDistinct, pDest,
+                    sqlite3WhereContinueLabel(pWInfo),
+                    sqlite3WhereBreakLabel(pWInfo));
 
     /* End the database scan loop.
     */
     sqlite3WhereEnd(pWInfo);
   }else{
-    /* This is the processing for aggregate queries */
+    /* This case when there exist aggregate functions or a GROUP BY clause
+    ** or both */
     NameContext sNC;    /* Name context for processing aggregate information */
     int iAMem;          /* First Mem address for storing current GROUP BY */
     int iBMem;          /* First Mem address for previous GROUP BY */
@@ -99702,9 +100770,9 @@ SQLITE_PRIVATE int sqlite3Select(
       for(k=pGroupBy->nExpr, pItem=pGroupBy->a; k>0; k--, pItem++){
         pItem->iAlias = 0;
       }
-      if( p->nSelectRow>(double)100 ) p->nSelectRow = (double)100;
+      if( p->nSelectRow>100 ) p->nSelectRow = 100;
     }else{
-      p->nSelectRow = (double)1;
+      p->nSelectRow = 1;
     }
 
  
@@ -99784,14 +100852,14 @@ SQLITE_PRIVATE int sqlite3Select(
       ** in the right order to begin with.
       */
       sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
-      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pGroupBy, 0, 0);
+      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, 0, 
+                                 WHERE_GROUPBY, 0);
       if( pWInfo==0 ) goto select_end;
-      if( pGroupBy==0 ){
+      if( sqlite3WhereIsOrdered(pWInfo) ){
         /* The optimizer is able to deliver rows in group by order so
         ** we do not have to sort.  The OP_OpenEphemeral table will be
         ** cancelled later because we still need to use the pKeyInfo
         */
-        pGroupBy = p->pGroupBy;
         groupBySort = 0;
       }else{
         /* Rows are coming out in undetermined order.  We have to push
@@ -99805,7 +100873,8 @@ SQLITE_PRIVATE int sqlite3Select(
         int nGroupBy;
 
         explainTempTable(pParse, 
-            isDistinct && !(p->selFlags&SF_Distinct)?"DISTINCT":"GROUP BY");
+            (sDistinct.isTnct && (p->selFlags&SF_Distinct)==0) ?
+                    "DISTINCT" : "GROUP BY");
 
         groupBySort = 1;
         nGroupBy = pGroupBy->nExpr;
@@ -99937,7 +101006,7 @@ SQLITE_PRIVATE int sqlite3Select(
       finalizeAggFunctions(pParse, &sAggInfo);
       sqlite3ExprIfFalse(pParse, pHaving, addrOutputRow+1, SQLITE_JUMPIFNULL);
       selectInnerLoop(pParse, p, p->pEList, 0, 0, pOrderBy,
-                      distinct, pDest,
+                      &sDistinct, pDest,
                       addrOutputRow+1, addrSetAbort);
       sqlite3VdbeAddOp1(v, OP_Return, regOutputRow);
       VdbeComment((v, "end groupby result generator"));
@@ -100025,7 +101094,7 @@ SQLITE_PRIVATE int sqlite3Select(
         ** value of x, the only row required).
         **
         ** A special flag must be passed to sqlite3WhereBegin() to slightly
-        ** modify behaviour as follows:
+        ** modify behavior as follows:
         **
         **   + If the query is a "SELECT min(x)", then the loop coded by
         **     where.c should not iterate over any values with a NULL value
@@ -100037,10 +101106,17 @@ SQLITE_PRIVATE int sqlite3Select(
         **     Refer to code and comments in where.c for details.
         */
         ExprList *pMinMax = 0;
-        u8 flag = minMaxQuery(p);
+        u8 flag = WHERE_ORDERBY_NORMAL;
+        
+        assert( p->pGroupBy==0 );
+        assert( flag==0 );
+        if( p->pHaving==0 ){
+          flag = minMaxQuery(&sAggInfo, &pMinMax);
+        }
+        assert( flag==0 || (pMinMax!=0 && pMinMax->nExpr==1) );
+
         if( flag ){
-          assert( !ExprHasProperty(p->pEList->a[0].pExpr, EP_xIsSelect) );
-          pMinMax = sqlite3ExprListDup(db, p->pEList->a[0].pExpr->x.pList,0);
+          pMinMax = sqlite3ExprListDup(db, pMinMax, 0);
           pDel = pMinMax;
           if( pMinMax && !db->mallocFailed ){
             pMinMax->a[0].sortOrder = flag!=WHERE_ORDERBY_MIN ?1:0;
@@ -100053,14 +101129,15 @@ SQLITE_PRIVATE int sqlite3Select(
         ** of output.
         */
         resetAccumulator(pParse, &sAggInfo);
-        pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pMinMax, 0, flag);
+        pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pMinMax,0,flag,0);
         if( pWInfo==0 ){
           sqlite3ExprListDelete(db, pDel);
           goto select_end;
         }
         updateAccumulator(pParse, &sAggInfo);
-        if( !pMinMax && flag ){
-          sqlite3VdbeAddOp2(v, OP_Goto, 0, pWInfo->iBreak);
+        assert( pMinMax==0 || pMinMax->nExpr==1 );
+        if( sqlite3WhereIsOrdered(pWInfo) ){
+          sqlite3VdbeAddOp2(v, OP_Goto, 0, sqlite3WhereBreakLabel(pWInfo));
           VdbeComment((v, "%s() by index",
                 (flag==WHERE_ORDERBY_MIN?"min":"max")));
         }
@@ -100070,7 +101147,7 @@ SQLITE_PRIVATE int sqlite3Select(
 
       pOrderBy = 0;
       sqlite3ExprIfFalse(pParse, pHaving, addrEnd, SQLITE_JUMPIFNULL);
-      selectInnerLoop(pParse, p, p->pEList, 0, 0, 0, -1, 
+      selectInnerLoop(pParse, p, p->pEList, 0, 0, 0, 0, 
                       pDest, addrEnd, addrEnd);
       sqlite3ExprListDelete(db, pDel);
     }
@@ -100078,7 +101155,7 @@ SQLITE_PRIVATE int sqlite3Select(
     
   } /* endif aggregate query */
 
-  if( distinct>=0 ){
+  if( sDistinct.eTnctType==WHERE_DISTINCT_UNORDERED ){
     explainTempTable(pParse, "DISTINCT");
   }
 
@@ -100195,7 +101272,10 @@ SQLITE_PRIVATE void sqlite3ExplainSelect(Vdbe *pVdbe, Select *p){
     sqlite3ExplainPrintf(pVdbe, "(null-select)");
     return;
   }
-  while( p->pPrior ) p = p->pPrior;
+  while( p->pPrior ){
+    p->pPrior->pNext = p;
+    p = p->pPrior;
+  }
   sqlite3ExplainPush(pVdbe);
   while( p ){
     explainOneSelect(pVdbe, p);
@@ -100525,7 +101605,7 @@ SQLITE_PRIVATE void sqlite3BeginTrigger(
     iDb = 1;
     pName = pName1;
   }else{
-    /* Figure out the db that the the trigger will be created in */
+    /* Figure out the db that the trigger will be created in */
     iDb = sqlite3TwoPartName(pParse, pName1, pName2, &pName);
     if( iDb<0 ){
       goto trigger_cleanup;
@@ -101143,6 +102223,15 @@ static int codeTriggerProgram(
     */
     pParse->eOrconf = (orconf==OE_Default)?pStep->orconf:(u8)orconf;
 
+    /* Clear the cookieGoto flag. When coding triggers, the cookieGoto 
+    ** variable is used as a flag to indicate to sqlite3ExprCodeConstants()
+    ** that it is not safe to refactor constants (this happens after the
+    ** start of the first loop in the SQL statement is coded - at that 
+    ** point code may be conditionally executed, so it is no longer safe to 
+    ** initialize constant register values).  */
+    assert( pParse->cookieGoto==0 || pParse->cookieGoto==-1 );
+    pParse->cookieGoto = 0;
+
     switch( pStep->op ){
       case TK_UPDATE: {
         sqlite3Update(pParse, 
@@ -101407,7 +102496,7 @@ SQLITE_PRIVATE void sqlite3CodeRowTriggerDirect(
 /*
 ** This is called to code the required FOR EACH ROW triggers for an operation
 ** on table pTab. The operation to code triggers for (INSERT, UPDATE or DELETE)
-** is given by the op paramater. The tr_tm parameter determines whether the
+** is given by the op parameter. The tr_tm parameter determines whether the
 ** BEFORE or AFTER triggers are coded. If the operation is an UPDATE, then
 ** parameter pChanges is passed the list of columns being modified.
 **
@@ -101748,6 +102837,7 @@ SQLITE_PRIVATE void sqlite3Update(
     }
     if( j>=pTab->nCol ){
       if( sqlite3IsRowid(pChanges->a[i].zName) ){
+        j = -1;
         chngRowid = 1;
         pRowidExpr = pChanges->a[i].pExpr;
       }else{
@@ -101760,7 +102850,8 @@ SQLITE_PRIVATE void sqlite3Update(
     {
       int rc;
       rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
-                           pTab->aCol[j].zName, db->aDb[iDb].zName);
+                            j<0 ? "ROWID" : pTab->aCol[j].zName,
+                            db->aDb[iDb].zName);
       if( rc==SQLITE_DENY ){
         goto update_cleanup;
       }else if( rc==SQLITE_IGNORE ){
@@ -101784,7 +102875,7 @@ SQLITE_PRIVATE void sqlite3Update(
   }
   for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
     int reg;
-    if( hasFK || chngRowid ){
+    if( hasFK || chngRowid || pIdx->pPartIdxWhere ){
       reg = ++pParse->nMem;
     }else{
       reg = 0;
@@ -101853,10 +102944,10 @@ SQLITE_PRIVATE void sqlite3Update(
   */
   sqlite3VdbeAddOp3(v, OP_Null, 0, regRowSet, regOldRowid);
   pWInfo = sqlite3WhereBegin(
-      pParse, pTabList, pWhere, 0, 0, WHERE_ONEPASS_DESIRED
+      pParse, pTabList, pWhere, 0, 0, WHERE_ONEPASS_DESIRED, 0
   );
   if( pWInfo==0 ) goto update_cleanup;
-  okOnePass = pWInfo->okOnePass;
+  okOnePass = sqlite3WhereOkOnePass(pWInfo);
 
   /* Remember the rowid of every item to be updated.
   */
@@ -101998,7 +103089,7 @@ SQLITE_PRIVATE void sqlite3Update(
 
     /* The row-trigger may have deleted the row being updated. In this
     ** case, jump to the next row. No updates or AFTER triggers are 
-    ** required. This behaviour - what happens when the row being updated
+    ** required. This behavior - what happens when the row being updated
     ** is deleted or renamed by a BEFORE trigger - is left undefined in the
     ** documentation.
     */
@@ -102299,6 +103390,7 @@ SQLITE_PRIVATE void sqlite3Vacuum(Parse *pParse){
   Vdbe *v = sqlite3GetVdbe(pParse);
   if( v ){
     sqlite3VdbeAddOp2(v, OP_Vacuum, 0, 0);
+    sqlite3VdbeUsesBtree(v, 0);
   }
   return;
 }
@@ -102324,7 +103416,7 @@ SQLITE_PRIVATE int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
     sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction");
     return SQLITE_ERROR;
   }
-  if( db->activeVdbeCnt>1 ){
+  if( db->nVdbeActive>1 ){
     sqlite3SetString(pzErrMsg, db,"cannot VACUUM - SQL statements in progress");
     return SQLITE_ERROR;
   }
@@ -102502,6 +103594,7 @@ SQLITE_PRIVATE int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
        BTREE_DEFAULT_CACHE_SIZE, 0,  /* Preserve the default page cache size */
        BTREE_TEXT_ENCODING,      0,  /* Preserve the text encoding */
        BTREE_USER_VERSION,       0,  /* Preserve the user version */
+       BTREE_APPLICATION_ID,     0,  /* Preserve the application id */
     };
 
     assert( 1==sqlite3BtreeIsInTrans(pTemp) );
@@ -102694,7 +103787,7 @@ SQLITE_PRIVATE void sqlite3VtabUnlock(VTable *pVTab){
 
   assert( db );
   assert( pVTab->nRef>0 );
-  assert( sqlite3SafetyCheckOk(db) );
+  assert( db->magic==SQLITE_MAGIC_OPEN || db->magic==SQLITE_MAGIC_ZOMBIE );
 
   pVTab->nRef--;
   if( pVTab->nRef==0 ){
@@ -102827,7 +103920,7 @@ SQLITE_PRIVATE void sqlite3VtabClear(sqlite3 *db, Table *p){
   if( p->azModuleArg ){
     int i;
     for(i=0; i<p->nModuleArg; i++){
-      sqlite3DbFree(db, p->azModuleArg[i]);
+      if( i!=1 ) sqlite3DbFree(db, p->azModuleArg[i]);
     }
     sqlite3DbFree(db, p->azModuleArg);
   }
@@ -102887,7 +103980,7 @@ SQLITE_PRIVATE void sqlite3VtabBeginParse(
   pTable->tabFlags |= TF_Virtual;
   pTable->nModuleArg = 0;
   addModuleArgument(db, pTable, sqlite3NameFromToken(db, pModuleName));
-  addModuleArgument(db, pTable, sqlite3DbStrDup(db, db->aDb[iDb].zName));
+  addModuleArgument(db, pTable, 0);
   addModuleArgument(db, pTable, sqlite3DbStrDup(db, pTable->zName));
   pParse->sNameToken.n = (int)(&pModuleName->z[pModuleName->n] - pName1->z);
 
@@ -103044,6 +104137,7 @@ static int vtabCallConstructor(
   int nArg = pTab->nModuleArg;
   char *zErr = 0;
   char *zModuleName = sqlite3MPrintf(db, "%s", pTab->zName);
+  int iDb;
 
   if( !zModuleName ){
     return SQLITE_NOMEM;
@@ -103057,6 +104151,9 @@ static int vtabCallConstructor(
   pVTable->db = db;
   pVTable->pMod = pMod;
 
+  iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+  pTab->azModuleArg[1] = db->aDb[iDb].zName;
+
   /* Invoke the virtual table constructor */
   assert( &db->pVtabCtx );
   assert( xConstruct );
@@ -103091,7 +104188,7 @@ static int vtabCallConstructor(
       /* If everything went according to plan, link the new VTable structure
       ** into the linked list headed by pTab->pVTable. Then loop through the 
       ** columns of the table to see if any of them contain the token "hidden".
-      ** If so, set the Column.isHidden flag and remove the token from
+      ** If so, set the Column COLFLAG_HIDDEN flag and remove the token from
       ** the type string.  */
       pVTable->pNext = pTab->pVTable;
       pTab->pVTable = pVTable;
@@ -103122,7 +104219,7 @@ static int vtabCallConstructor(
             assert(zType[i-1]==' ');
             zType[i-1] = '\0';
           }
-          pTab->aCol[iCol].isHidden = 1;
+          pTab->aCol[iCol].colFlags |= COLFLAG_HIDDEN;
         }
       }
     }
@@ -103369,10 +104466,9 @@ static void callFinaliser(sqlite3 *db, int offset){
 ** array. Return the error code for the first error that occurs, or
 ** SQLITE_OK if all xSync operations are successful.
 **
-** Set *pzErrmsg to point to a buffer that should be released using 
-** sqlite3DbFree() containing an error message, if one is available.
+** If an error message is available, leave it in p->zErrMsg.
 */
-SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, char **pzErrmsg){
+SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, Vdbe *p){
   int i;
   int rc = SQLITE_OK;
   VTable **aVTrans = db->aVTrans;
@@ -103383,9 +104479,7 @@ SQLITE_PRIVATE int sqlite3VtabSync(sqlite3 *db, char **pzErrmsg){
     sqlite3_vtab *pVtab = aVTrans[i]->pVtab;
     if( pVtab && (x = pVtab->pModule->xSync)!=0 ){
       rc = x(pVtab);
-      sqlite3DbFree(db, *pzErrmsg);
-      *pzErrmsg = sqlite3DbStrDup(db, pVtab->zErrMsg);
-      sqlite3_free(pVtab->zErrMsg);
+      sqlite3VtabImportErrmsg(p, pVtab);
     }
   }
   db->aVTrans = aVTrans;
@@ -103683,21 +104777,190 @@ SQLITE_API int sqlite3_vtab_config(sqlite3 *db, int op, ...){
 ** Trace output macros
 */
 #if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
-SQLITE_PRIVATE int sqlite3WhereTrace = 0;
+/***/ int sqlite3WhereTrace = 0;
 #endif
-#if defined(SQLITE_TEST) && defined(SQLITE_DEBUG)
-# define WHERETRACE(X)  if(sqlite3WhereTrace) sqlite3DebugPrintf X
+#if defined(SQLITE_DEBUG) \
+    && (defined(SQLITE_TEST) || defined(SQLITE_ENABLE_WHERETRACE))
+# define WHERETRACE(K,X)  if(sqlite3WhereTrace&(K)) sqlite3DebugPrintf X
+# define WHERETRACE_ENABLED 1
 #else
-# define WHERETRACE(X)
+# define WHERETRACE(K,X)
 #endif
 
-/* Forward reference
+/* Forward references
 */
 typedef struct WhereClause WhereClause;
 typedef struct WhereMaskSet WhereMaskSet;
 typedef struct WhereOrInfo WhereOrInfo;
 typedef struct WhereAndInfo WhereAndInfo;
-typedef struct WhereCost WhereCost;
+typedef struct WhereLevel WhereLevel;
+typedef struct WhereLoop WhereLoop;
+typedef struct WherePath WherePath;
+typedef struct WhereTerm WhereTerm;
+typedef struct WhereLoopBuilder WhereLoopBuilder;
+typedef struct WhereScan WhereScan;
+typedef struct WhereOrCost WhereOrCost;
+typedef struct WhereOrSet WhereOrSet;
+
+/*
+** Cost X is tracked as 10*log2(X) stored in a 16-bit integer.  The
+** maximum cost for ordinary tables is 64*(2**63) which becomes 6900.
+** (Virtual tables can return a larger cost, but let's assume they do not.)
+** So all costs can be stored in a 16-bit unsigned integer without risk
+** of overflow.
+**
+** Costs are estimates, so no effort is made to compute 10*log2(X) exactly.
+** Instead, a close estimate is used.  Any value of X<=1 is stored as 0.
+** X=2 is 10.  X=3 is 16.  X=1000 is 99. etc.
+**
+** The tool/wherecosttest.c source file implements a command-line program
+** that will convert WhereCosts to integers, convert integers to WhereCosts
+** and do addition and multiplication on WhereCost values.  The wherecosttest
+** command-line program is a useful utility to have around when working with
+** this module.
+*/
+typedef unsigned short int WhereCost;
+
+/*
+** This object contains information needed to implement a single nested
+** loop in WHERE clause.
+**
+** Contrast this object with WhereLoop.  This object describes the
+** implementation of the loop.  WhereLoop describes the algorithm.
+** This object contains a pointer to the WhereLoop algorithm as one of
+** its elements.
+**
+** The WhereInfo object contains a single instance of this object for
+** each term in the FROM clause (which is to say, for each of the
+** nested loops as implemented).  The order of WhereLevel objects determines
+** the loop nested order, with WhereInfo.a[0] being the outer loop and
+** WhereInfo.a[WhereInfo.nLevel-1] being the inner loop.
+*/
+struct WhereLevel {
+  int iLeftJoin;        /* Memory cell used to implement LEFT OUTER JOIN */
+  int iTabCur;          /* The VDBE cursor used to access the table */
+  int iIdxCur;          /* The VDBE cursor used to access pIdx */
+  int addrBrk;          /* Jump here to break out of the loop */
+  int addrNxt;          /* Jump here to start the next IN combination */
+  int addrCont;         /* Jump here to continue with the next loop cycle */
+  int addrFirst;        /* First instruction of interior of the loop */
+  int addrBody;         /* Beginning of the body of this loop */
+  u8 iFrom;             /* Which entry in the FROM clause */
+  u8 op, p5;            /* Opcode and P5 of the opcode that ends the loop */
+  int p1, p2;           /* Operands of the opcode used to ends the loop */
+  union {               /* Information that depends on pWLoop->wsFlags */
+    struct {
+      int nIn;              /* Number of entries in aInLoop[] */
+      struct InLoop {
+        int iCur;              /* The VDBE cursor used by this IN operator */
+        int addrInTop;         /* Top of the IN loop */
+        u8 eEndLoopOp;         /* IN Loop terminator. OP_Next or OP_Prev */
+      } *aInLoop;           /* Information about each nested IN operator */
+    } in;                 /* Used when pWLoop->wsFlags&WHERE_IN_ABLE */
+    Index *pCovidx;       /* Possible covering index for WHERE_MULTI_OR */
+  } u;
+  struct WhereLoop *pWLoop;  /* The selected WhereLoop object */
+};
+
+/*
+** Each instance of this object represents an algorithm for evaluating one
+** term of a join.  Every term of the FROM clause will have at least
+** one corresponding WhereLoop object (unless INDEXED BY constraints
+** prevent a query solution - which is an error) and many terms of the
+** FROM clause will have multiple WhereLoop objects, each describing a
+** potential way of implementing that FROM-clause term, together with
+** dependencies and cost estimates for using the chosen algorithm.
+**
+** Query planning consists of building up a collection of these WhereLoop
+** objects, then computing a particular sequence of WhereLoop objects, with
+** one WhereLoop object per FROM clause term, that satisfy all dependencies
+** and that minimize the overall cost.
+*/
+struct WhereLoop {
+  Bitmask prereq;       /* Bitmask of other loops that must run first */
+  Bitmask maskSelf;     /* Bitmask identifying table iTab */
+#ifdef SQLITE_DEBUG
+  char cId;             /* Symbolic ID of this loop for debugging use */
+#endif
+  u8 iTab;              /* Position in FROM clause of table for this loop */
+  u8 iSortIdx;          /* Sorting index number.  0==None */
+  WhereCost rSetup;     /* One-time setup cost (ex: create transient index) */
+  WhereCost rRun;       /* Cost of running each loop */
+  WhereCost nOut;       /* Estimated number of output rows */
+  union {
+    struct {               /* Information for internal btree tables */
+      int nEq;               /* Number of equality constraints */
+      Index *pIndex;         /* Index used, or NULL */
+    } btree;
+    struct {               /* Information for virtual tables */
+      int idxNum;            /* Index number */
+      u8 needFree;           /* True if sqlite3_free(idxStr) is needed */
+      u8 isOrdered;          /* True if satisfies ORDER BY */
+      u16 omitMask;          /* Terms that may be omitted */
+      char *idxStr;          /* Index identifier string */
+    } vtab;
+  } u;
+  u32 wsFlags;          /* WHERE_* flags describing the plan */
+  u16 nLTerm;           /* Number of entries in aLTerm[] */
+  /**** whereLoopXfer() copies fields above ***********************/
+# define WHERE_LOOP_XFER_SZ offsetof(WhereLoop,nLSlot)
+  u16 nLSlot;           /* Number of slots allocated for aLTerm[] */
+  WhereTerm **aLTerm;   /* WhereTerms used */
+  WhereLoop *pNextLoop; /* Next WhereLoop object in the WhereClause */
+  WhereTerm *aLTermSpace[4];  /* Initial aLTerm[] space */
+};
+
+/* This object holds the prerequisites and the cost of running a
+** subquery on one operand of an OR operator in the WHERE clause.
+** See WhereOrSet for additional information 
+*/
+struct WhereOrCost {
+  Bitmask prereq;     /* Prerequisites */
+  WhereCost rRun;     /* Cost of running this subquery */
+  WhereCost nOut;     /* Number of outputs for this subquery */
+};
+
+/* The WhereOrSet object holds a set of possible WhereOrCosts that
+** correspond to the subquery(s) of OR-clause processing.  Only the
+** best N_OR_COST elements are retained.
+*/
+#define N_OR_COST 3
+struct WhereOrSet {
+  u16 n;                      /* Number of valid a[] entries */
+  WhereOrCost a[N_OR_COST];   /* Set of best costs */
+};
+
+
+/* Forward declaration of methods */
+static int whereLoopResize(sqlite3*, WhereLoop*, int);
+
+/*
+** Each instance of this object holds a sequence of WhereLoop objects
+** that implement some or all of a query plan.
+**
+** Think of each WhereLoop object as a node in a graph with arcs
+** showing dependences and costs for travelling between nodes.  (That is
+** not a completely accurate description because WhereLoop costs are a
+** vector, not a scalar, and because dependences are many-to-one, not
+** one-to-one as are graph nodes.  But it is a useful visualization aid.)
+** Then a WherePath object is a path through the graph that visits some
+** or all of the WhereLoop objects once.
+**
+** The "solver" works by creating the N best WherePath objects of length
+** 1.  Then using those as a basis to compute the N best WherePath objects
+** of length 2.  And so forth until the length of WherePaths equals the
+** number of nodes in the FROM clause.  The best (lowest cost) WherePath
+** at the end is the choosen query plan.
+*/
+struct WherePath {
+  Bitmask maskLoop;     /* Bitmask of all WhereLoop objects in this path */
+  Bitmask revLoop;      /* aLoop[]s that should be reversed for ORDER BY */
+  WhereCost nRow;       /* Estimated number of rows generated by this path */
+  WhereCost rCost;      /* Total cost of this path */
+  u8 isOrdered;         /* True if this path satisfies ORDER BY */
+  u8 isOrderedValid;    /* True if the isOrdered field is valid */
+  WhereLoop **aLoop;    /* Array of WhereLoop objects implementing this path */
+};
 
 /*
 ** The query generator uses an array of instances of this structure to
@@ -103725,9 +104988,9 @@ typedef struct WhereCost WhereCost;
 **
 **         (t1.X <op> <expr>) OR (t1.Y <op> <expr>) OR ....
 **
-** In this second case, wtFlag as the TERM_ORINFO set and eOperator==WO_OR
+** In this second case, wtFlag has the TERM_ORINFO bit set and eOperator==WO_OR
 ** and the WhereTerm.u.pOrInfo field points to auxiliary information that
-** is collected about the
+** is collected about the OR clause.
 **
 ** If a term in the WHERE clause does not match either of the two previous
 ** categories, then eOperator==0.  The WhereTerm.pExpr field is still set
@@ -103750,15 +105013,14 @@ typedef struct WhereCost WhereCost;
 ** in prereqRight and prereqAll.  The default is 64 bits, hence SQLite
 ** is only able to process joins with 64 or fewer tables.
 */
-typedef struct WhereTerm WhereTerm;
 struct WhereTerm {
   Expr *pExpr;            /* Pointer to the subexpression that is this term */
   int iParent;            /* Disable pWC->a[iParent] when this term disabled */
   int leftCursor;         /* Cursor number of X in "X <op> <expr>" */
   union {
     int leftColumn;         /* Column number of X in "X <op> <expr>" */
-    WhereOrInfo *pOrInfo;   /* Extra information if eOperator==WO_OR */
-    WhereAndInfo *pAndInfo; /* Extra information if eOperator==WO_AND */
+    WhereOrInfo *pOrInfo;   /* Extra information if (eOperator & WO_OR)!=0 */
+    WhereAndInfo *pAndInfo; /* Extra information if (eOperator& WO_AND)!=0 */
   } u;
   u16 eOperator;          /* A WO_xx value describing <op> */
   u8 wtFlags;             /* TERM_xxx bit flags.  See below */
@@ -103784,6 +105046,22 @@ struct WhereTerm {
 #  define TERM_VNULL    0x00   /* Disabled if not using stat3 */
 #endif
 
+/*
+** An instance of the WhereScan object is used as an iterator for locating
+** terms in the WHERE clause that are useful to the query planner.
+*/
+struct WhereScan {
+  WhereClause *pOrigWC;      /* Original, innermost WhereClause */
+  WhereClause *pWC;          /* WhereClause currently being scanned */
+  char *zCollName;           /* Required collating sequence, if not NULL */
+  char idxaff;               /* Must match this affinity, if zCollName!=NULL */
+  unsigned char nEquiv;      /* Number of entries in aEquiv[] */
+  unsigned char iEquiv;      /* Next unused slot in aEquiv[] */
+  u32 opMask;                /* Acceptable operators */
+  int k;                     /* Resume scanning at this->pWC->a[this->k] */
+  int aEquiv[22];            /* Cursor,Column pairs for equivalence classes */
+};
+
 /*
 ** An instance of the following structure holds all information about a
 ** WHERE clause.  Mostly this is a container for one or more WhereTerms.
@@ -103797,12 +105075,9 @@ struct WhereTerm {
 ** subclauses points to the WhereClause object for the whole clause.
 */
 struct WhereClause {
-  Parse *pParse;           /* The parser context */
-  WhereMaskSet *pMaskSet;  /* Mapping of table cursor numbers to bitmasks */
-  Bitmask vmask;           /* Bitmask identifying virtual table cursors */
+  WhereInfo *pWInfo;       /* WHERE clause processing context */
   WhereClause *pOuter;     /* Outer conjunction */
   u8 op;                   /* Split operator.  TK_AND or TK_OR */
-  u16 wctrlFlags;          /* Might include WHERE_AND_ONLY */
   int nTerm;               /* Number of terms */
   int nSlot;               /* Number of entries in a[] */
   WhereTerm *a;            /* Each a[] describes a term of the WHERE cluase */
@@ -103862,19 +105137,55 @@ struct WhereMaskSet {
 };
 
 /*
-** A WhereCost object records a lookup strategy and the estimated
-** cost of pursuing that strategy.
+** This object is a convenience wrapper holding all information needed
+** to construct WhereLoop objects for a particular query.
 */
-struct WhereCost {
-  WherePlan plan;    /* The lookup strategy */
-  double rCost;      /* Overall cost of pursuing this search strategy */
-  Bitmask used;      /* Bitmask of cursors used by this plan */
+struct WhereLoopBuilder {
+  WhereInfo *pWInfo;        /* Information about this WHERE */
+  WhereClause *pWC;         /* WHERE clause terms */
+  ExprList *pOrderBy;       /* ORDER BY clause */
+  WhereLoop *pNew;          /* Template WhereLoop */
+  WhereOrSet *pOrSet;       /* Record best loops here, if not NULL */
 };
 
 /*
-** Bitmasks for the operators that indices are able to exploit.  An
+** The WHERE clause processing routine has two halves.  The
+** first part does the start of the WHERE loop and the second
+** half does the tail of the WHERE loop.  An instance of
+** this structure is returned by the first half and passed
+** into the second half to give some continuity.
+**
+** An instance of this object holds the complete state of the query
+** planner.
+*/
+struct WhereInfo {
+  Parse *pParse;            /* Parsing and code generating context */
+  SrcList *pTabList;        /* List of tables in the join */
+  ExprList *pOrderBy;       /* The ORDER BY clause or NULL */
+  ExprList *pResultSet;     /* Result set. DISTINCT operates on these */
+  WhereLoop *pLoops;        /* List of all WhereLoop objects */
+  Bitmask revMask;          /* Mask of ORDER BY terms that need reversing */
+  WhereCost nRowOut;        /* Estimated number of output rows */
+  u16 wctrlFlags;           /* Flags originally passed to sqlite3WhereBegin() */
+  u8 bOBSat;                /* ORDER BY satisfied by indices */
+  u8 okOnePass;             /* Ok to use one-pass algorithm for UPDATE/DELETE */
+  u8 untestedTerms;         /* Not all WHERE terms resolved by outer loop */
+  u8 eDistinct;             /* One of the WHERE_DISTINCT_* values below */
+  u8 nLevel;                /* Number of nested loop */
+  int iTop;                 /* The very beginning of the WHERE loop */
+  int iContinue;            /* Jump here to continue with next record */
+  int iBreak;               /* Jump here to break out of the loop */
+  int savedNQueryLoop;      /* pParse->nQueryLoop outside the WHERE loop */
+  WhereMaskSet sMaskSet;    /* Map cursor numbers to bitmasks */
+  WhereClause sWC;          /* Decomposition of the WHERE clause */
+  WhereLevel a[1];          /* Information about each nest loop in WHERE */
+};
+
+/*
+** Bitmasks for the operators on WhereTerm objects.  These are all
+** operators that are of interest to the query planner.  An
 ** OR-ed combination of these values can be used when searching for
-** terms in the where clause.
+** particular WhereTerms within a WhereClause.
 */
 #define WO_IN     0x001
 #define WO_EQ     0x002
@@ -103886,62 +105197,157 @@ struct WhereCost {
 #define WO_ISNULL 0x080
 #define WO_OR     0x100       /* Two or more OR-connected terms */
 #define WO_AND    0x200       /* Two or more AND-connected terms */
+#define WO_EQUIV  0x400       /* Of the form A==B, both columns */
 #define WO_NOOP   0x800       /* This term does not restrict search space */
 
 #define WO_ALL    0xfff       /* Mask of all possible WO_* values */
 #define WO_SINGLE 0x0ff       /* Mask of all non-compound WO_* values */
 
 /*
-** Value for wsFlags returned by bestIndex() and stored in
-** WhereLevel.wsFlags.  These flags determine which search
-** strategies are appropriate.
-**
-** The least significant 12 bits is reserved as a mask for WO_ values above.
-** The WhereLevel.wsFlags field is usually set to WO_IN|WO_EQ|WO_ISNULL.
-** But if the table is the right table of a left join, WhereLevel.wsFlags
-** is set to WO_IN|WO_EQ.  The WhereLevel.wsFlags field can then be used as
-** the "op" parameter to findTerm when we are resolving equality constraints.
-** ISNULL constraints will then not be used on the right table of a left
-** join.  Tickets #2177 and #2189.
+** These are definitions of bits in the WhereLoop.wsFlags field.
+** The particular combination of bits in each WhereLoop help to
+** determine the algorithm that WhereLoop represents.
 */
-#define WHERE_ROWID_EQ     0x00001000  /* rowid=EXPR or rowid IN (...) */
-#define WHERE_ROWID_RANGE  0x00002000  /* rowid<EXPR and/or rowid>EXPR */
-#define WHERE_COLUMN_EQ    0x00010000  /* x=EXPR or x IN (...) or x IS NULL */
-#define WHERE_COLUMN_RANGE 0x00020000  /* x<EXPR and/or x>EXPR */
-#define WHERE_COLUMN_IN    0x00040000  /* x IN (...) */
-#define WHERE_COLUMN_NULL  0x00080000  /* x IS NULL */
-#define WHERE_INDEXED      0x000f0000  /* Anything that uses an index */
-#define WHERE_NOT_FULLSCAN 0x100f3000  /* Does not do a full table scan */
-#define WHERE_IN_ABLE      0x000f1000  /* Able to support an IN operator */
-#define WHERE_TOP_LIMIT    0x00100000  /* x<EXPR or x<=EXPR constraint */
-#define WHERE_BTM_LIMIT    0x00200000  /* x>EXPR or x>=EXPR constraint */
-#define WHERE_BOTH_LIMIT   0x00300000  /* Both x>EXPR and x<EXPR */
-#define WHERE_IDX_ONLY     0x00800000  /* Use index only - omit table */
-#define WHERE_ORDERBY      0x01000000  /* Output will appear in correct order */
-#define WHERE_REVERSE      0x02000000  /* Scan in reverse order */
-#define WHERE_UNIQUE       0x04000000  /* Selects no more than one row */
-#define WHERE_VIRTUALTABLE 0x08000000  /* Use virtual-table processing */
-#define WHERE_MULTI_OR     0x10000000  /* OR using multiple indices */
-#define WHERE_TEMP_INDEX   0x20000000  /* Uses an ephemeral index */
-#define WHERE_DISTINCT     0x40000000  /* Correct order for DISTINCT */
+#define WHERE_COLUMN_EQ    0x00000001  /* x=EXPR */
+#define WHERE_COLUMN_RANGE 0x00000002  /* x<EXPR and/or x>EXPR */
+#define WHERE_COLUMN_IN    0x00000004  /* x IN (...) */
+#define WHERE_COLUMN_NULL  0x00000008  /* x IS NULL */
+#define WHERE_CONSTRAINT   0x0000000f  /* Any of the WHERE_COLUMN_xxx values */
+#define WHERE_TOP_LIMIT    0x00000010  /* x<EXPR or x<=EXPR constraint */
+#define WHERE_BTM_LIMIT    0x00000020  /* x>EXPR or x>=EXPR constraint */
+#define WHERE_BOTH_LIMIT   0x00000030  /* Both x>EXPR and x<EXPR */
+#define WHERE_IDX_ONLY     0x00000040  /* Use index only - omit table */
+#define WHERE_IPK          0x00000100  /* x is the INTEGER PRIMARY KEY */
+#define WHERE_INDEXED      0x00000200  /* WhereLoop.u.btree.pIndex is valid */
+#define WHERE_VIRTUALTABLE 0x00000400  /* WhereLoop.u.vtab is valid */
+#define WHERE_IN_ABLE      0x00000800  /* Able to support an IN operator */
+#define WHERE_ONEROW       0x00001000  /* Selects no more than one row */
+#define WHERE_MULTI_OR     0x00002000  /* OR using multiple indices */
+#define WHERE_AUTO_INDEX   0x00004000  /* Uses an ephemeral index */
+
+
+/* Convert a WhereCost value (10 times log2(X)) into its integer value X.
+** A rough approximation is used.  The value returned is not exact.
+*/
+static u64 whereCostToInt(WhereCost x){
+  u64 n;
+  if( x<10 ) return 1;
+  n = x%10;
+  x /= 10;
+  if( n>=5 ) n -= 2;
+  else if( n>=1 ) n -= 1;
+  if( x>=3 ) return (n+8)<<(x-3);
+  return (n+8)>>(3-x);
+}
+
+/*
+** Return the estimated number of output rows from a WHERE clause
+*/
+SQLITE_PRIVATE u64 sqlite3WhereOutputRowCount(WhereInfo *pWInfo){
+  return whereCostToInt(pWInfo->nRowOut);
+}
+
+/*
+** Return one of the WHERE_DISTINCT_xxxxx values to indicate how this
+** WHERE clause returns outputs for DISTINCT processing.
+*/
+SQLITE_PRIVATE int sqlite3WhereIsDistinct(WhereInfo *pWInfo){
+  return pWInfo->eDistinct;
+}
+
+/*
+** Return TRUE if the WHERE clause returns rows in ORDER BY order.
+** Return FALSE if the output needs to be sorted.
+*/
+SQLITE_PRIVATE int sqlite3WhereIsOrdered(WhereInfo *pWInfo){
+  return pWInfo->bOBSat!=0;
+}
+
+/*
+** Return the VDBE address or label to jump to in order to continue
+** immediately with the next row of a WHERE clause.
+*/
+SQLITE_PRIVATE int sqlite3WhereContinueLabel(WhereInfo *pWInfo){
+  return pWInfo->iContinue;
+}
+
+/*
+** Return the VDBE address or label to jump to in order to break
+** out of a WHERE loop.
+*/
+SQLITE_PRIVATE int sqlite3WhereBreakLabel(WhereInfo *pWInfo){
+  return pWInfo->iBreak;
+}
+
+/*
+** Return TRUE if an UPDATE or DELETE statement can operate directly on
+** the rowids returned by a WHERE clause.  Return FALSE if doing an
+** UPDATE or DELETE might change subsequent WHERE clause results.
+*/
+SQLITE_PRIVATE int sqlite3WhereOkOnePass(WhereInfo *pWInfo){
+  return pWInfo->okOnePass;
+}
+
+/*
+** Move the content of pSrc into pDest
+*/
+static void whereOrMove(WhereOrSet *pDest, WhereOrSet *pSrc){
+  pDest->n = pSrc->n;
+  memcpy(pDest->a, pSrc->a, pDest->n*sizeof(pDest->a[0]));
+}
+
+/*
+** Try to insert a new prerequisite/cost entry into the WhereOrSet pSet.
+**
+** The new entry might overwrite an existing entry, or it might be
+** appended, or it might be discarded.  Do whatever is the right thing
+** so that pSet keeps the N_OR_COST best entries seen so far.
+*/
+static int whereOrInsert(
+  WhereOrSet *pSet,      /* The WhereOrSet to be updated */
+  Bitmask prereq,        /* Prerequisites of the new entry */
+  WhereCost rRun,        /* Run-cost of the new entry */
+  WhereCost nOut         /* Number of outputs for the new entry */
+){
+  u16 i;
+  WhereOrCost *p;
+  for(i=pSet->n, p=pSet->a; i>0; i--, p++){
+    if( rRun<=p->rRun && (prereq & p->prereq)==prereq ){
+      goto whereOrInsert_done;
+    }
+    if( p->rRun<=rRun && (p->prereq & prereq)==p->prereq ){
+      return 0;
+    }
+  }
+  if( pSet->n<N_OR_COST ){
+    p = &pSet->a[pSet->n++];
+    p->nOut = nOut;
+  }else{
+    p = pSet->a;
+    for(i=1; i<pSet->n; i++){
+      if( p->rRun>pSet->a[i].rRun ) p = pSet->a + i;
+    }
+    if( p->rRun<=rRun ) return 0;
+  }
+whereOrInsert_done:
+  p->prereq = prereq;
+  p->rRun = rRun;
+  if( p->nOut>nOut ) p->nOut = nOut;
+  return 1;
+}
 
 /*
 ** Initialize a preallocated WhereClause structure.
 */
 static void whereClauseInit(
   WhereClause *pWC,        /* The WhereClause to be initialized */
-  Parse *pParse,           /* The parsing context */
-  WhereMaskSet *pMaskSet,  /* Mapping from table cursor numbers to bitmasks */
-  u16 wctrlFlags           /* Might include WHERE_AND_ONLY */
+  WhereInfo *pWInfo        /* The WHERE processing context */
 ){
-  pWC->pParse = pParse;
-  pWC->pMaskSet = pMaskSet;
+  pWC->pWInfo = pWInfo;
   pWC->pOuter = 0;
   pWC->nTerm = 0;
   pWC->nSlot = ArraySize(pWC->aStatic);
   pWC->a = pWC->aStatic;
-  pWC->vmask = 0;
-  pWC->wctrlFlags = wctrlFlags;
 }
 
 /* Forward reference */
@@ -103970,7 +105376,7 @@ static void whereAndInfoDelete(sqlite3 *db, WhereAndInfo *p){
 static void whereClauseClear(WhereClause *pWC){
   int i;
   WhereTerm *a;
-  sqlite3 *db = pWC->pParse->db;
+  sqlite3 *db = pWC->pWInfo->pParse->db;
   for(i=pWC->nTerm-1, a=pWC->a; i>=0; i--, a++){
     if( a->wtFlags & TERM_DYNAMIC ){
       sqlite3ExprDelete(db, a->pExpr);
@@ -104008,10 +105414,10 @@ static void whereClauseClear(WhereClause *pWC){
 static int whereClauseInsert(WhereClause *pWC, Expr *p, u8 wtFlags){
   WhereTerm *pTerm;
   int idx;
-  testcase( wtFlags & TERM_VIRTUAL );  /* EV: R-00211-15100 */
+  testcase( wtFlags & TERM_VIRTUAL );
   if( pWC->nTerm>=pWC->nSlot ){
     WhereTerm *pOld = pWC->a;
-    sqlite3 *db = pWC->pParse->db;
+    sqlite3 *db = pWC->pWInfo->pParse->db;
     pWC->a = sqlite3DbMallocRaw(db, sizeof(pWC->a[0])*pWC->nSlot*2 );
     if( pWC->a==0 ){
       if( wtFlags & TERM_DYNAMIC ){
@@ -104027,7 +105433,7 @@ static int whereClauseInsert(WhereClause *pWC, Expr *p, u8 wtFlags){
     pWC->nSlot = sqlite3DbMallocSize(db, pWC->a)/sizeof(pWC->a[0]);
   }
   pTerm = &pWC->a[idx = pWC->nTerm++];
-  pTerm->pExpr = p;
+  pTerm->pExpr = sqlite3ExprSkipCollate(p);
   pTerm->wtFlags = wtFlags;
   pTerm->pWC = pWC;
   pTerm->iParent = -1;
@@ -104051,8 +105457,8 @@ static int whereClauseInsert(WhereClause *pWC, Expr *p, u8 wtFlags){
 ** the WhereClause.a[] array.  The slot[] array grows as needed to contain
 ** all terms of the WHERE clause.
 */
-static void whereSplit(WhereClause *pWC, Expr *pExpr, int op){
-  pWC->op = (u8)op;
+static void whereSplit(WhereClause *pWC, Expr *pExpr, u8 op){
+  pWC->op = op;
   if( pExpr==0 ) return;
   if( pExpr->op!=op ){
     whereClauseInsert(pWC, pExpr, 0);
@@ -104063,9 +105469,9 @@ static void whereSplit(WhereClause *pWC, Expr *pExpr, int op){
 }
 
 /*
-** Initialize an expression mask set (a WhereMaskSet object)
+** Initialize a WhereMaskSet object
 */
-#define initMaskSet(P)  memset(P, 0, sizeof(*P))
+#define initMaskSet(P)  (P)->n=0
 
 /*
 ** Return the bitmask for the given cursor number.  Return 0 if
@@ -104076,7 +105482,7 @@ static Bitmask getMask(WhereMaskSet *pMaskSet, int iCursor){
   assert( pMaskSet->n<=(int)sizeof(Bitmask)*8 );
   for(i=0; i<pMaskSet->n; i++){
     if( pMaskSet->ix[i]==iCursor ){
-      return ((Bitmask)1)<<i;
+      return MASKBIT(i);
     }
   }
   return 0;
@@ -104096,18 +105502,9 @@ static void createMask(WhereMaskSet *pMaskSet, int iCursor){
 }
 
 /*
-** This routine walks (recursively) an expression tree and generates
+** These routines walk (recursively) an expression tree and generate
 ** a bitmask indicating which tables are used in that expression
 ** tree.
-**
-** In order for this routine to work, the calling function must have
-** previously invoked sqlite3ResolveExprNames() on the expression.  See
-** the header comment on that routine for additional information.
-** The sqlite3ResolveExprNames() routines looks for column names and
-** sets their opcodes to TK_COLUMN and their Expr.iTable fields to
-** the VDBE cursor number of the table.  This routine just has to
-** translate the cursor numbers into bitmask values and OR all
-** the bitmasks together.
 */
 static Bitmask exprListTableUsage(WhereMaskSet*, ExprList*);
 static Bitmask exprSelectTableUsage(WhereMaskSet*, Select*);
@@ -104161,14 +105558,7 @@ static Bitmask exprSelectTableUsage(WhereMaskSet *pMaskSet, Select *pS){
 /*
 ** Return TRUE if the given operator is one of the operators that is
 ** allowed for an indexable WHERE clause term.  The allowed operators are
-** "=", "<", ">", "<=", ">=", and "IN".
-**
-** IMPLEMENTATION-OF: R-59926-26393 To be usable by an index a term must be
-** of one of the following forms: column = expression column > expression
-** column >= expression column < expression column <= expression
-** expression = column expression > column expression >= column
-** expression < column expression <= column column IN
-** (expression-list) column IN (subquery) column IS NULL
+** "=", "<", ">", "<=", ">=", "IN", and "IS NULL"
 */
 static int allowedOp(int op){
   assert( TK_GT>TK_EQ && TK_GT<TK_GE );
@@ -104187,23 +105577,31 @@ static int allowedOp(int op){
 ** Commute a comparison operator.  Expressions of the form "X op Y"
 ** are converted into "Y op X".
 **
-** If a collation sequence is associated with either the left or right
-** side of the comparison, it remains associated with the same side after
-** the commutation. So "Y collate NOCASE op X" becomes 
-** "X collate NOCASE op Y". This is because any collation sequence on
+** If left/right precedence rules come into play when determining the
+** collating sequence, then COLLATE operators are adjusted to ensure
+** that the collating sequence does not change.  For example:
+** "Y collate NOCASE op X" becomes "X op Y" because any collation sequence on
 ** the left hand side of a comparison overrides any collation sequence 
-** attached to the right. For the same reason the EP_ExpCollate flag
+** attached to the right. For the same reason the EP_Collate flag
 ** is not commuted.
 */
 static void exprCommute(Parse *pParse, Expr *pExpr){
-  u16 expRight = (pExpr->pRight->flags & EP_ExpCollate);
-  u16 expLeft = (pExpr->pLeft->flags & EP_ExpCollate);
+  u16 expRight = (pExpr->pRight->flags & EP_Collate);
+  u16 expLeft = (pExpr->pLeft->flags & EP_Collate);
   assert( allowedOp(pExpr->op) && pExpr->op!=TK_IN );
-  pExpr->pRight->pColl = sqlite3ExprCollSeq(pParse, pExpr->pRight);
-  pExpr->pLeft->pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft);
-  SWAP(CollSeq*,pExpr->pRight->pColl,pExpr->pLeft->pColl);
-  pExpr->pRight->flags = (pExpr->pRight->flags & ~EP_ExpCollate) | expLeft;
-  pExpr->pLeft->flags = (pExpr->pLeft->flags & ~EP_ExpCollate) | expRight;
+  if( expRight==expLeft ){
+    /* Either X and Y both have COLLATE operator or neither do */
+    if( expRight ){
+      /* Both X and Y have COLLATE operators.  Make sure X is always
+      ** used by clearing the EP_Collate flag from Y. */
+      pExpr->pRight->flags &= ~EP_Collate;
+    }else if( sqlite3ExprCollSeq(pParse, pExpr->pLeft)!=0 ){
+      /* Neither X nor Y have COLLATE operators, but X has a non-default
+      ** collating sequence.  So add the EP_Collate marker on X to cause
+      ** it to be searched first. */
+      pExpr->pLeft->flags |= EP_Collate;
+    }
+  }
   SWAP(Expr*,pExpr->pRight,pExpr->pLeft);
   if( pExpr->op>=TK_GT ){
     assert( TK_LT==TK_GT+2 );
@@ -104239,11 +105637,152 @@ static u16 operatorMask(int op){
   return c;
 }
 
+/*
+** Advance to the next WhereTerm that matches according to the criteria
+** established when the pScan object was initialized by whereScanInit().
+** Return NULL if there are no more matching WhereTerms.
+*/
+static WhereTerm *whereScanNext(WhereScan *pScan){
+  int iCur;            /* The cursor on the LHS of the term */
+  int iColumn;         /* The column on the LHS of the term.  -1 for IPK */
+  Expr *pX;            /* An expression being tested */
+  WhereClause *pWC;    /* Shorthand for pScan->pWC */
+  WhereTerm *pTerm;    /* The term being tested */
+  int k = pScan->k;    /* Where to start scanning */
+
+  while( pScan->iEquiv<=pScan->nEquiv ){
+    iCur = pScan->aEquiv[pScan->iEquiv-2];
+    iColumn = pScan->aEquiv[pScan->iEquiv-1];
+    while( (pWC = pScan->pWC)!=0 ){
+      for(pTerm=pWC->a+k; k<pWC->nTerm; k++, pTerm++){
+        if( pTerm->leftCursor==iCur && pTerm->u.leftColumn==iColumn ){
+          if( (pTerm->eOperator & WO_EQUIV)!=0
+           && pScan->nEquiv<ArraySize(pScan->aEquiv)
+          ){
+            int j;
+            pX = sqlite3ExprSkipCollate(pTerm->pExpr->pRight);
+            assert( pX->op==TK_COLUMN );
+            for(j=0; j<pScan->nEquiv; j+=2){
+              if( pScan->aEquiv[j]==pX->iTable
+               && pScan->aEquiv[j+1]==pX->iColumn ){
+                  break;
+              }
+            }
+            if( j==pScan->nEquiv ){
+              pScan->aEquiv[j] = pX->iTable;
+              pScan->aEquiv[j+1] = pX->iColumn;
+              pScan->nEquiv += 2;
+            }
+          }
+          if( (pTerm->eOperator & pScan->opMask)!=0 ){
+            /* Verify the affinity and collating sequence match */
+            if( pScan->zCollName && (pTerm->eOperator & WO_ISNULL)==0 ){
+              CollSeq *pColl;
+              Parse *pParse = pWC->pWInfo->pParse;
+              pX = pTerm->pExpr;
+              if( !sqlite3IndexAffinityOk(pX, pScan->idxaff) ){
+                continue;
+              }
+              assert(pX->pLeft);
+              pColl = sqlite3BinaryCompareCollSeq(pParse,
+                                                  pX->pLeft, pX->pRight);
+              if( pColl==0 ) pColl = pParse->db->pDfltColl;
+              if( sqlite3StrICmp(pColl->zName, pScan->zCollName) ){
+                continue;
+              }
+            }
+            if( (pTerm->eOperator & WO_EQ)!=0
+             && (pX = pTerm->pExpr->pRight)->op==TK_COLUMN
+             && pX->iTable==pScan->aEquiv[0]
+             && pX->iColumn==pScan->aEquiv[1]
+            ){
+              continue;
+            }
+            pScan->k = k+1;
+            return pTerm;
+          }
+        }
+      }
+      pScan->pWC = pScan->pWC->pOuter;
+      k = 0;
+    }
+    pScan->pWC = pScan->pOrigWC;
+    k = 0;
+    pScan->iEquiv += 2;
+  }
+  return 0;
+}
+
+/*
+** Initialize a WHERE clause scanner object.  Return a pointer to the
+** first match.  Return NULL if there are no matches.
+**
+** The scanner will be searching the WHERE clause pWC.  It will look
+** for terms of the form "X <op> <expr>" where X is column iColumn of table
+** iCur.  The <op> must be one of the operators described by opMask.
+**
+** If the search is for X and the WHERE clause contains terms of the
+** form X=Y then this routine might also return terms of the form
+** "Y <op> <expr>".  The number of levels of transitivity is limited,
+** but is enough to handle most commonly occurring SQL statements.
+**
+** If X is not the INTEGER PRIMARY KEY then X must be compatible with
+** index pIdx.
+*/
+static WhereTerm *whereScanInit(
+  WhereScan *pScan,       /* The WhereScan object being initialized */
+  WhereClause *pWC,       /* The WHERE clause to be scanned */
+  int iCur,               /* Cursor to scan for */
+  int iColumn,            /* Column to scan for */
+  u32 opMask,             /* Operator(s) to scan for */
+  Index *pIdx             /* Must be compatible with this index */
+){
+  int j;
+
+  /* memset(pScan, 0, sizeof(*pScan)); */
+  pScan->pOrigWC = pWC;
+  pScan->pWC = pWC;
+  if( pIdx && iColumn>=0 ){
+    pScan->idxaff = pIdx->pTable->aCol[iColumn].affinity;
+    for(j=0; pIdx->aiColumn[j]!=iColumn; j++){
+      if( NEVER(j>=pIdx->nColumn) ) return 0;
+    }
+    pScan->zCollName = pIdx->azColl[j];
+  }else{
+    pScan->idxaff = 0;
+    pScan->zCollName = 0;
+  }
+  pScan->opMask = opMask;
+  pScan->k = 0;
+  pScan->aEquiv[0] = iCur;
+  pScan->aEquiv[1] = iColumn;
+  pScan->nEquiv = 2;
+  pScan->iEquiv = 2;
+  return whereScanNext(pScan);
+}
+
 /*
 ** Search for a term in the WHERE clause that is of the form "X <op> <expr>"
 ** where X is a reference to the iColumn of table iCur and <op> is one of
 ** the WO_xx operator codes specified by the op parameter.
 ** Return a pointer to the term.  Return 0 if not found.
+**
+** The term returned might by Y=<expr> if there is another constraint in
+** the WHERE clause that specifies that X=Y.  Any such constraints will be
+** identified by the WO_EQUIV bit in the pTerm->eOperator field.  The
+** aEquiv[] array holds X and all its equivalents, with each SQL variable
+** taking up two slots in aEquiv[].  The first slot is for the cursor number
+** and the second is for the column number.  There are 22 slots in aEquiv[]
+** so that means we can look for X plus up to 10 other equivalent values.
+** Hence a search for X will return <expr> if X=A1 and A1=A2 and A2=A3
+** and ... and A9=A10 and A10=<expr>.
+**
+** If there are multiple terms in the WHERE clause of the form "X <op> <expr>"
+** then try for the one with no dependencies on <expr> - in other words where
+** <expr> is a constant expression of some kind.  Only return entries of
+** the form "X <op> Y" where Y is a column in another table if no terms of
+** the form "X <op> <const-expr>" exist.   If no terms with a constant RHS
+** exist, try to return a term that does not use WO_EQUIV.
 */
 static WhereTerm *findTerm(
   WhereClause *pWC,     /* The WHERE clause to be searched */
@@ -104253,45 +105792,21 @@ static WhereTerm *findTerm(
   u32 op,               /* Mask of WO_xx values describing operator */
   Index *pIdx           /* Must be compatible with this index, if not NULL */
 ){
-  WhereTerm *pTerm;
-  int k;
-  assert( iCur>=0 );
-  op &= WO_ALL;
-  for(; pWC; pWC=pWC->pOuter){
-    for(pTerm=pWC->a, k=pWC->nTerm; k; k--, pTerm++){
-      if( pTerm->leftCursor==iCur
-         && (pTerm->prereqRight & notReady)==0
-         && pTerm->u.leftColumn==iColumn
-         && (pTerm->eOperator & op)!=0
-      ){
-        if( iColumn>=0 && pIdx && pTerm->eOperator!=WO_ISNULL ){
-          Expr *pX = pTerm->pExpr;
-          CollSeq *pColl;
-          char idxaff;
-          int j;
-          Parse *pParse = pWC->pParse;
-  
-          idxaff = pIdx->pTable->aCol[iColumn].affinity;
-          if( !sqlite3IndexAffinityOk(pX, idxaff) ) continue;
-  
-          /* Figure out the collation sequence required from an index for
-          ** it to be useful for optimising expression pX. Store this
-          ** value in variable pColl.
-          */
-          assert(pX->pLeft);
-          pColl = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pX->pRight);
-          assert(pColl || pParse->nErr);
-  
-          for(j=0; pIdx->aiColumn[j]!=iColumn; j++){
-            if( NEVER(j>=pIdx->nColumn) ) return 0;
-          }
-          if( pColl && sqlite3StrICmp(pColl->zName, pIdx->azColl[j]) ) continue;
-        }
-        return pTerm;
+  WhereTerm *pResult = 0;
+  WhereTerm *p;
+  WhereScan scan;
+
+  p = whereScanInit(&scan, pWC, iCur, iColumn, op, pIdx);
+  while( p ){
+    if( (p->prereqRight & notReady)==0 ){
+      if( p->prereqRight==0 && (p->eOperator&WO_EQ)!=0 ){
+        return p;
       }
+      if( pResult==0 ) pResult = p;
     }
+    p = whereScanNext(&scan);
   }
-  return 0;
+  return pResult;
 }
 
 /* Forward reference */
@@ -104299,8 +105814,6 @@ static void exprAnalyze(SrcList*, WhereClause*, int);
 
 /*
 ** Call exprAnalyze on all terms in a WHERE clause.  
-**
-**
 */
 static void exprAnalyzeAll(
   SrcList *pTabList,       /* the FROM clause */
@@ -104364,7 +105877,7 @@ static int isLikeOrGlob(
   if( op==TK_VARIABLE ){
     Vdbe *pReprepare = pParse->pReprepare;
     int iCol = pRight->iColumn;
-    pVal = sqlite3VdbeGetValue(pReprepare, iCol, SQLITE_AFF_NONE);
+    pVal = sqlite3VdbeGetBoundValue(pReprepare, iCol, SQLITE_AFF_NONE);
     if( pVal && sqlite3_value_type(pVal)==SQLITE_TEXT ){
       z = (char *)sqlite3_value_text(pVal);
     }
@@ -104446,8 +105959,10 @@ static int isMatchOfColumn(
 ** a join, then transfer the appropriate markings over to derived.
 */
 static void transferJoinMarkings(Expr *pDerived, Expr *pBase){
-  pDerived->flags |= pBase->flags & EP_FromJoin;
-  pDerived->iRightJoinTable = pBase->iRightJoinTable;
+  if( pDerived ){
+    pDerived->flags |= pBase->flags & EP_FromJoin;
+    pDerived->iRightJoinTable = pBase->iRightJoinTable;
+  }
 }
 
 #if !defined(SQLITE_OMIT_OR_OPTIMIZATION) && !defined(SQLITE_OMIT_SUBQUERY)
@@ -104477,7 +105992,7 @@ static void transferJoinMarkings(Expr *pDerived, Expr *pBase){
 **
 ** CASE 1:
 **
-** If all subterms are of the form T.C=expr for some single column of C
+** If all subterms are of the form T.C=expr for some single column of C and
 ** a single table T (as shown in example B above) then create a new virtual
 ** term that is an equivalent IN expression.  In other words, if the term
 ** being analyzed is:
@@ -104506,10 +106021,10 @@ static void transferJoinMarkings(Expr *pDerived, Expr *pBase){
 ** From another point of view, "indexable" means that the subterm could
 ** potentially be used with an index if an appropriate index exists.
 ** This analysis does not consider whether or not the index exists; that
-** is something the bestIndex() routine will determine.  This analysis
-** only looks at whether subterms appropriate for indexing exist.
+** is decided elsewhere.  This analysis only looks at whether subterms
+** appropriate for indexing exist.
 **
-** All examples A through E above all satisfy case 2.  But if a term
+** All examples A through E above satisfy case 2.  But if a term
 ** also statisfies case 1 (such as B) we know that the optimizer will
 ** always prefer case 1, so in that case we pretend that case 2 is not
 ** satisfied.
@@ -104532,11 +106047,11 @@ static void exprAnalyzeOrTerm(
   WhereClause *pWC,         /* the complete WHERE clause */
   int idxTerm               /* Index of the OR-term to be analyzed */
 ){
-  Parse *pParse = pWC->pParse;            /* Parser context */
+  WhereInfo *pWInfo = pWC->pWInfo;        /* WHERE clause processing context */
+  Parse *pParse = pWInfo->pParse;         /* Parser context */
   sqlite3 *db = pParse->db;               /* Database connection */
   WhereTerm *pTerm = &pWC->a[idxTerm];    /* The term to be analyzed */
   Expr *pExpr = pTerm->pExpr;             /* The expression of the term */
-  WhereMaskSet *pMaskSet = pWC->pMaskSet; /* Table use masks */
   int i;                                  /* Loop counters */
   WhereClause *pOrWc;       /* Breakup of pTerm into subterms */
   WhereTerm *pOrTerm;       /* A Sub-term within the pOrWc */
@@ -104555,7 +106070,7 @@ static void exprAnalyzeOrTerm(
   if( pOrInfo==0 ) return;
   pTerm->wtFlags |= TERM_ORINFO;
   pOrWc = &pOrInfo->wc;
-  whereClauseInit(pOrWc, pWC->pParse, pMaskSet, pWC->wctrlFlags);
+  whereClauseInit(pOrWc, pWInfo);
   whereSplit(pOrWc, pExpr, TK_OR);
   exprAnalyzeAll(pSrc, pOrWc);
   if( db->mallocFailed ) return;
@@ -104565,11 +106080,10 @@ static void exprAnalyzeOrTerm(
   ** Compute the set of tables that might satisfy cases 1 or 2.
   */
   indexable = ~(Bitmask)0;
-  chngToIN = ~(pWC->vmask);
+  chngToIN = ~(Bitmask)0;
   for(i=pOrWc->nTerm-1, pOrTerm=pOrWc->a; i>=0 && indexable; i--, pOrTerm++){
     if( (pOrTerm->eOperator & WO_SINGLE)==0 ){
       WhereAndInfo *pAndInfo;
-      assert( pOrTerm->eOperator==0 );
       assert( (pOrTerm->wtFlags & (TERM_ANDINFO|TERM_ORINFO))==0 );
       chngToIN = 0;
       pAndInfo = sqlite3DbMallocRaw(db, sizeof(*pAndInfo));
@@ -104582,7 +106096,7 @@ static void exprAnalyzeOrTerm(
         pOrTerm->wtFlags |= TERM_ANDINFO;
         pOrTerm->eOperator = WO_AND;
         pAndWC = &pAndInfo->wc;
-        whereClauseInit(pAndWC, pWC->pParse, pMaskSet, pWC->wctrlFlags);
+        whereClauseInit(pAndWC, pWC->pWInfo);
         whereSplit(pAndWC, pOrTerm->pExpr, TK_AND);
         exprAnalyzeAll(pSrc, pAndWC);
         pAndWC->pOuter = pWC;
@@ -104591,7 +106105,7 @@ static void exprAnalyzeOrTerm(
           for(j=0, pAndTerm=pAndWC->a; j<pAndWC->nTerm; j++, pAndTerm++){
             assert( pAndTerm->pExpr );
             if( allowedOp(pAndTerm->pExpr->op) ){
-              b |= getMask(pMaskSet, pAndTerm->leftCursor);
+              b |= getMask(&pWInfo->sMaskSet, pAndTerm->leftCursor);
             }
           }
         }
@@ -104602,13 +106116,13 @@ static void exprAnalyzeOrTerm(
       ** corresponding TERM_VIRTUAL term */
     }else{
       Bitmask b;
-      b = getMask(pMaskSet, pOrTerm->leftCursor);
+      b = getMask(&pWInfo->sMaskSet, pOrTerm->leftCursor);
       if( pOrTerm->wtFlags & TERM_VIRTUAL ){
         WhereTerm *pOther = &pOrWc->a[pOrTerm->iParent];
-        b |= getMask(pMaskSet, pOther->leftCursor);
+        b |= getMask(&pWInfo->sMaskSet, pOther->leftCursor);
       }
       indexable &= b;
-      if( pOrTerm->eOperator!=WO_EQ ){
+      if( (pOrTerm->eOperator & WO_EQ)==0 ){
         chngToIN = 0;
       }else{
         chngToIN &= b;
@@ -104659,7 +106173,7 @@ static void exprAnalyzeOrTerm(
     for(j=0; j<2 && !okToChngToIN; j++){
       pOrTerm = pOrWc->a;
       for(i=pOrWc->nTerm-1; i>=0; i--, pOrTerm++){
-        assert( pOrTerm->eOperator==WO_EQ );
+        assert( pOrTerm->eOperator & WO_EQ );
         pOrTerm->wtFlags &= ~TERM_OR_OK;
         if( pOrTerm->leftCursor==iCursor ){
           /* This is the 2-bit case and we are on the second iteration and
@@ -104667,7 +106181,7 @@ static void exprAnalyzeOrTerm(
           assert( j==1 );
           continue;
         }
-        if( (chngToIN & getMask(pMaskSet, pOrTerm->leftCursor))==0 ){
+        if( (chngToIN & getMask(&pWInfo->sMaskSet, pOrTerm->leftCursor))==0 ){
           /* This term must be of the form t1.a==t2.b where t2 is in the
           ** chngToIN set but t1 is not.  This term will be either preceeded
           ** or follwed by an inverted copy (t2.b==t1.a).  Skip this term 
@@ -104685,8 +106199,8 @@ static void exprAnalyzeOrTerm(
         /* No candidate table+column was found.  This can only occur
         ** on the second iteration */
         assert( j==1 );
-        assert( (chngToIN&(chngToIN-1))==0 );
-        assert( chngToIN==getMask(pMaskSet, iCursor) );
+        assert( IsPowerOfTwo(chngToIN) );
+        assert( chngToIN==getMask(&pWInfo->sMaskSet, iCursor) );
         break;
       }
       testcase( j==1 );
@@ -104695,7 +106209,7 @@ static void exprAnalyzeOrTerm(
       ** table and column is common to every term in the OR clause */
       okToChngToIN = 1;
       for(; i>=0 && okToChngToIN; i--, pOrTerm++){
-        assert( pOrTerm->eOperator==WO_EQ );
+        assert( pOrTerm->eOperator & WO_EQ );
         if( pOrTerm->leftCursor!=iCursor ){
           pOrTerm->wtFlags &= ~TERM_OR_OK;
         }else if( pOrTerm->u.leftColumn!=iColumn ){
@@ -104720,8 +106234,6 @@ static void exprAnalyzeOrTerm(
     /* At this point, okToChngToIN is true if original pTerm satisfies
     ** case 1.  In that case, construct a new virtual term that is 
     ** pTerm converted into an IN operator.
-    **
-    ** EV: R-00211-15100
     */
     if( okToChngToIN ){
       Expr *pDup;            /* A transient duplicate expression */
@@ -104731,11 +106243,11 @@ static void exprAnalyzeOrTerm(
 
       for(i=pOrWc->nTerm-1, pOrTerm=pOrWc->a; i>=0; i--, pOrTerm++){
         if( (pOrTerm->wtFlags & TERM_OR_OK)==0 ) continue;
-        assert( pOrTerm->eOperator==WO_EQ );
+        assert( pOrTerm->eOperator & WO_EQ );
         assert( pOrTerm->leftCursor==iCursor );
         assert( pOrTerm->u.leftColumn==iColumn );
         pDup = sqlite3ExprDup(db, pOrTerm->pExpr->pRight, 0);
-        pList = sqlite3ExprListAppend(pWC->pParse, pList, pDup);
+        pList = sqlite3ExprListAppend(pWInfo->pParse, pList, pDup);
         pLeft = pOrTerm->pExpr->pLeft;
       }
       assert( pLeft!=0 );
@@ -104761,7 +106273,6 @@ static void exprAnalyzeOrTerm(
 }
 #endif /* !SQLITE_OMIT_OR_OPTIMIZATION && !SQLITE_OMIT_SUBQUERY */
 
-
 /*
 ** The input to this routine is an WhereTerm structure with only the
 ** "pExpr" field filled in.  The job of this routine is to analyze the
@@ -104785,6 +106296,7 @@ static void exprAnalyze(
   WhereClause *pWC,         /* the WHERE clause */
   int idxTerm               /* Index of the term to be analyzed */
 ){
+  WhereInfo *pWInfo = pWC->pWInfo; /* WHERE clause processing context */
   WhereTerm *pTerm;                /* The term to be analyzed */
   WhereMaskSet *pMaskSet;          /* Set of table index masks */
   Expr *pExpr;                     /* The expression to be analyzed */
@@ -104795,15 +106307,16 @@ static void exprAnalyze(
   int isComplete = 0;              /* RHS of LIKE/GLOB ends with wildcard */
   int noCase = 0;                  /* LIKE/GLOB distinguishes case */
   int op;                          /* Top-level operator.  pExpr->op */
-  Parse *pParse = pWC->pParse;     /* Parsing context */
+  Parse *pParse = pWInfo->pParse;  /* Parsing context */
   sqlite3 *db = pParse->db;        /* Database connection */
 
   if( db->mallocFailed ){
     return;
   }
   pTerm = &pWC->a[idxTerm];
-  pMaskSet = pWC->pMaskSet;
+  pMaskSet = &pWInfo->sMaskSet;
   pExpr = pTerm->pExpr;
+  assert( pExpr->op!=TK_AS && pExpr->op!=TK_COLLATE );
   prereqLeft = exprTableUsage(pMaskSet, pExpr->pLeft);
   op = pExpr->op;
   if( op==TK_IN ){
@@ -104829,17 +106342,19 @@ static void exprAnalyze(
   pTerm->leftCursor = -1;
   pTerm->iParent = -1;
   pTerm->eOperator = 0;
-  if( allowedOp(op) && (pTerm->prereqRight & prereqLeft)==0 ){
-    Expr *pLeft = pExpr->pLeft;
-    Expr *pRight = pExpr->pRight;
+  if( allowedOp(op) ){
+    Expr *pLeft = sqlite3ExprSkipCollate(pExpr->pLeft);
+    Expr *pRight = sqlite3ExprSkipCollate(pExpr->pRight);
+    u16 opMask = (pTerm->prereqRight & prereqLeft)==0 ? WO_ALL : WO_EQUIV;
     if( pLeft->op==TK_COLUMN ){
       pTerm->leftCursor = pLeft->iTable;
       pTerm->u.leftColumn = pLeft->iColumn;
-      pTerm->eOperator = operatorMask(op);
+      pTerm->eOperator = operatorMask(op) & opMask;
     }
     if( pRight && pRight->op==TK_COLUMN ){
       WhereTerm *pNew;
       Expr *pDup;
+      u16 eExtraOp = 0;        /* Extra bits for pNew->eOperator */
       if( pTerm->leftCursor>=0 ){
         int idxNew;
         pDup = sqlite3ExprDup(db, pExpr, 0);
@@ -104854,18 +106369,25 @@ static void exprAnalyze(
         pTerm = &pWC->a[idxTerm];
         pTerm->nChild = 1;
         pTerm->wtFlags |= TERM_COPIED;
+        if( pExpr->op==TK_EQ
+         && !ExprHasProperty(pExpr, EP_FromJoin)
+         && OptimizationEnabled(db, SQLITE_Transitive)
+        ){
+          pTerm->eOperator |= WO_EQUIV;
+          eExtraOp = WO_EQUIV;
+        }
       }else{
         pDup = pExpr;
         pNew = pTerm;
       }
       exprCommute(pParse, pDup);
-      pLeft = pDup->pLeft;
+      pLeft = sqlite3ExprSkipCollate(pDup->pLeft);
       pNew->leftCursor = pLeft->iTable;
       pNew->u.leftColumn = pLeft->iColumn;
       testcase( (prereqLeft | extraRight) != prereqLeft );
       pNew->prereqRight = prereqLeft | extraRight;
       pNew->prereqAll = prereqAll;
-      pNew->eOperator = operatorMask(pDup->op);
+      pNew->eOperator = (operatorMask(pDup->op) + eExtraOp) & opMask;
     }
   }
 
@@ -104897,6 +106419,7 @@ static void exprAnalyze(
       pNewExpr = sqlite3PExpr(pParse, ops[i], 
                              sqlite3ExprDup(db, pExpr->pLeft, 0),
                              sqlite3ExprDup(db, pList->a[i].pExpr, 0), 0);
+      transferJoinMarkings(pNewExpr, pExpr);
       idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
       testcase( idxNew==0 );
       exprAnalyze(pSrc, pWC, idxNew);
@@ -104938,7 +106461,7 @@ static void exprAnalyze(
     Expr *pNewExpr2;
     int idxNew1;
     int idxNew2;
-    CollSeq *pColl;    /* Collating sequence to use */
+    Token sCollSeqName;  /* Name of collating sequence */
 
     pLeft = pExpr->x.pList->a[1].pExpr;
     pStr2 = sqlite3ExprDup(db, pStr1, 0);
@@ -104953,23 +106476,26 @@ static void exprAnalyze(
         ** inequality.  To avoid this, make sure to also run the full
         ** LIKE on all candidate expressions by clearing the isComplete flag
         */
-        if( c=='A'-1 ) isComplete = 0;   /* EV: R-64339-08207 */
-
-
+        if( c=='A'-1 ) isComplete = 0;
         c = sqlite3UpperToLower[c];
       }
       *pC = c + 1;
     }
-    pColl = sqlite3FindCollSeq(db, SQLITE_UTF8, noCase ? "NOCASE" : "BINARY",0);
+    sCollSeqName.z = noCase ? "NOCASE" : "BINARY";
+    sCollSeqName.n = 6;
+    pNewExpr1 = sqlite3ExprDup(db, pLeft, 0);
     pNewExpr1 = sqlite3PExpr(pParse, TK_GE, 
-                     sqlite3ExprSetColl(sqlite3ExprDup(db,pLeft,0), pColl),
-                     pStr1, 0);
+           sqlite3ExprAddCollateToken(pParse,pNewExpr1,&sCollSeqName),
+           pStr1, 0);
+    transferJoinMarkings(pNewExpr1, pExpr);
     idxNew1 = whereClauseInsert(pWC, pNewExpr1, TERM_VIRTUAL|TERM_DYNAMIC);
     testcase( idxNew1==0 );
     exprAnalyze(pSrc, pWC, idxNew1);
+    pNewExpr2 = sqlite3ExprDup(db, pLeft, 0);
     pNewExpr2 = sqlite3PExpr(pParse, TK_LT,
-                     sqlite3ExprSetColl(sqlite3ExprDup(db,pLeft,0), pColl),
-                     pStr2, 0);
+           sqlite3ExprAddCollateToken(pParse,pNewExpr2,&sCollSeqName),
+           pStr2, 0);
+    transferJoinMarkings(pNewExpr2, pExpr);
     idxNew2 = whereClauseInsert(pWC, pNewExpr2, TERM_VIRTUAL|TERM_DYNAMIC);
     testcase( idxNew2==0 );
     exprAnalyze(pSrc, pWC, idxNew2);
@@ -105033,6 +106559,7 @@ static void exprAnalyze(
   if( pExpr->op==TK_NOTNULL
    && pExpr->pLeft->op==TK_COLUMN
    && pExpr->pLeft->iColumn>=0
+   && OptimizationEnabled(db, SQLITE_Stat3)
   ){
     Expr *pNewExpr;
     Expr *pLeft = pExpr->pLeft;
@@ -105067,30 +106594,8 @@ static void exprAnalyze(
 }
 
 /*
-** Return TRUE if any of the expressions in pList->a[iFirst...] contain
-** a reference to any table other than the iBase table.
-*/
-static int referencesOtherTables(
-  ExprList *pList,          /* Search expressions in ths list */
-  WhereMaskSet *pMaskSet,   /* Mapping from tables to bitmaps */
-  int iFirst,               /* Be searching with the iFirst-th expression */
-  int iBase                 /* Ignore references to this table */
-){
-  Bitmask allowed = ~getMask(pMaskSet, iBase);
-  while( iFirst<pList->nExpr ){
-    if( (exprTableUsage(pMaskSet, pList->a[iFirst++].pExpr)&allowed)!=0 ){
-      return 1;
-    }
-  }
-  return 0;
-}
-
-/*
-** This function searches the expression list passed as the second argument
-** for an expression of type TK_COLUMN that refers to the same column and
-** uses the same collation sequence as the iCol'th column of index pIdx.
-** Argument iBase is the cursor number used for the table that pIdx refers
-** to.
+** This function searches pList for a entry that matches the iCol-th column
+** of index pIdx.
 **
 ** If such an expression is found, its index in pList->a[] is returned. If
 ** no expression is found, -1 is returned.
@@ -105106,12 +106611,12 @@ static int findIndexCol(
   const char *zColl = pIdx->azColl[iCol];
 
   for(i=0; i<pList->nExpr; i++){
-    Expr *p = pList->a[i].pExpr;
+    Expr *p = sqlite3ExprSkipCollate(pList->a[i].pExpr);
     if( p->op==TK_COLUMN
      && p->iColumn==pIdx->aiColumn[iCol]
      && p->iTable==iBase
     ){
-      CollSeq *pColl = sqlite3ExprCollSeq(pParse, p);
+      CollSeq *pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);
       if( ALWAYS(pColl) && 0==sqlite3StrICmp(pColl->zName, zColl) ){
         return i;
       }
@@ -105121,76 +106626,18 @@ static int findIndexCol(
   return -1;
 }
 
-/*
-** This routine determines if pIdx can be used to assist in processing a
-** DISTINCT qualifier. In other words, it tests whether or not using this
-** index for the outer loop guarantees that rows with equal values for
-** all expressions in the pDistinct list are delivered grouped together.
-**
-** For example, the query 
-**
-**   SELECT DISTINCT a, b, c FROM tbl WHERE a = ?
-**
-** can benefit from any index on columns "b" and "c".
-*/
-static int isDistinctIndex(
-  Parse *pParse,                  /* Parsing context */
-  WhereClause *pWC,               /* The WHERE clause */
-  Index *pIdx,                    /* The index being considered */
-  int base,                       /* Cursor number for the table pIdx is on */
-  ExprList *pDistinct,            /* The DISTINCT expressions */
-  int nEqCol                      /* Number of index columns with == */
-){
-  Bitmask mask = 0;               /* Mask of unaccounted for pDistinct exprs */
-  int i;                          /* Iterator variable */
-
-  if( pIdx->zName==0 || pDistinct==0 || pDistinct->nExpr>=BMS ) return 0;
-  testcase( pDistinct->nExpr==BMS-1 );
-
-  /* Loop through all the expressions in the distinct list. If any of them
-  ** are not simple column references, return early. Otherwise, test if the
-  ** WHERE clause contains a "col=X" clause. If it does, the expression
-  ** can be ignored. If it does not, and the column does not belong to the
-  ** same table as index pIdx, return early. Finally, if there is no
-  ** matching "col=X" expression and the column is on the same table as pIdx,
-  ** set the corresponding bit in variable mask.
-  */
-  for(i=0; i<pDistinct->nExpr; i++){
-    WhereTerm *pTerm;
-    Expr *p = pDistinct->a[i].pExpr;
-    if( p->op!=TK_COLUMN ) return 0;
-    pTerm = findTerm(pWC, p->iTable, p->iColumn, ~(Bitmask)0, WO_EQ, 0);
-    if( pTerm ){
-      Expr *pX = pTerm->pExpr;
-      CollSeq *p1 = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pX->pRight);
-      CollSeq *p2 = sqlite3ExprCollSeq(pParse, p);
-      if( p1==p2 ) continue;
-    }
-    if( p->iTable!=base ) return 0;
-    mask |= (((Bitmask)1) << i);
-  }
-
-  for(i=nEqCol; mask && i<pIdx->nColumn; i++){
-    int iExpr = findIndexCol(pParse, pDistinct, base, pIdx, i);
-    if( iExpr<0 ) break;
-    mask &= ~(((Bitmask)1) << iExpr);
-  }
-
-  return (mask==0);
-}
-
-
 /*
 ** Return true if the DISTINCT expression-list passed as the third argument
-** is redundant. A DISTINCT list is redundant if the database contains a
-** UNIQUE index that guarantees that the result of the query will be distinct
-** anyway.
+** is redundant.
+**
+** A DISTINCT list is redundant if the database contains some subset of
+** columns that are unique and non-null.
 */
 static int isDistinctRedundant(
-  Parse *pParse,
-  SrcList *pTabList,
-  WhereClause *pWC,
-  ExprList *pDistinct
+  Parse *pParse,            /* Parsing context */
+  SrcList *pTabList,        /* The FROM clause */
+  WhereClause *pWC,         /* The WHERE clause */
+  ExprList *pDistinct       /* The result set that needs to be DISTINCT */
 ){
   Table *pTab;
   Index *pIdx;
@@ -105209,7 +106656,7 @@ static int isDistinctRedundant(
   ** current SELECT is a correlated sub-query.
   */
   for(i=0; i<pDistinct->nExpr; i++){
-    Expr *p = pDistinct->a[i].pExpr;
+    Expr *p = sqlite3ExprSkipCollate(pDistinct->a[i].pExpr);
     if( p->op==TK_COLUMN && p->iTable==iBase && p->iColumn<0 ) return 1;
   }
 
@@ -105246,180 +106693,76 @@ static int isDistinctRedundant(
   return 0;
 }
 
-/*
-** This routine decides if pIdx can be used to satisfy the ORDER BY
-** clause.  If it can, it returns 1.  If pIdx cannot satisfy the
-** ORDER BY clause, this routine returns 0.
-**
-** pOrderBy is an ORDER BY clause from a SELECT statement.  pTab is the
-** left-most table in the FROM clause of that same SELECT statement and
-** the table has a cursor number of "base".  pIdx is an index on pTab.
-**
-** nEqCol is the number of columns of pIdx that are used as equality
-** constraints.  Any of these columns may be missing from the ORDER BY
-** clause and the match can still be a success.
-**
-** All terms of the ORDER BY that match against the index must be either
-** ASC or DESC.  (Terms of the ORDER BY clause past the end of a UNIQUE
-** index do not need to satisfy this constraint.)  The *pbRev value is
-** set to 1 if the ORDER BY clause is all DESC and it is set to 0 if
-** the ORDER BY clause is all ASC.
+/* 
+** Find (an approximate) sum of two WhereCosts.  This computation is
+** not a simple "+" operator because WhereCost is stored as a logarithmic
+** value.
+** 
 */
-static int isSortingIndex(
-  Parse *pParse,          /* Parsing context */
-  WhereMaskSet *pMaskSet, /* Mapping from table cursor numbers to bitmaps */
-  Index *pIdx,            /* The index we are testing */
-  int base,               /* Cursor number for the table to be sorted */
-  ExprList *pOrderBy,     /* The ORDER BY clause */
-  int nEqCol,             /* Number of index columns with == constraints */
-  int wsFlags,            /* Index usages flags */
-  int *pbRev              /* Set to 1 if ORDER BY is DESC */
-){
-  int i, j;                       /* Loop counters */
-  int sortOrder = 0;              /* XOR of index and ORDER BY sort direction */
-  int nTerm;                      /* Number of ORDER BY terms */
-  struct ExprList_item *pTerm;    /* A term of the ORDER BY clause */
-  sqlite3 *db = pParse->db;
-
-  if( !pOrderBy ) return 0;
-  if( wsFlags & WHERE_COLUMN_IN ) return 0;
-  if( pIdx->bUnordered ) return 0;
-
-  nTerm = pOrderBy->nExpr;
-  assert( nTerm>0 );
-
-  /* Argument pIdx must either point to a 'real' named index structure, 
-  ** or an index structure allocated on the stack by bestBtreeIndex() to
-  ** represent the rowid index that is part of every table.  */
-  assert( pIdx->zName || (pIdx->nColumn==1 && pIdx->aiColumn[0]==-1) );
-
-  /* Match terms of the ORDER BY clause against columns of
-  ** the index.
-  **
-  ** Note that indices have pIdx->nColumn regular columns plus
-  ** one additional column containing the rowid.  The rowid column
-  ** of the index is also allowed to match against the ORDER BY
-  ** clause.
-  */
-  for(i=j=0, pTerm=pOrderBy->a; j<nTerm && i<=pIdx->nColumn; i++){
-    Expr *pExpr;       /* The expression of the ORDER BY pTerm */
-    CollSeq *pColl;    /* The collating sequence of pExpr */
-    int termSortOrder; /* Sort order for this term */
-    int iColumn;       /* The i-th column of the index.  -1 for rowid */
-    int iSortOrder;    /* 1 for DESC, 0 for ASC on the i-th index term */
-    const char *zColl; /* Name of the collating sequence for i-th index term */
-
-    pExpr = pTerm->pExpr;
-    if( pExpr->op!=TK_COLUMN || pExpr->iTable!=base ){
-      /* Can not use an index sort on anything that is not a column in the
-      ** left-most table of the FROM clause */
-      break;
-    }
-    pColl = sqlite3ExprCollSeq(pParse, pExpr);
-    if( !pColl ){
-      pColl = db->pDfltColl;
-    }
-    if( pIdx->zName && i<pIdx->nColumn ){
-      iColumn = pIdx->aiColumn[i];
-      if( iColumn==pIdx->pTable->iPKey ){
-        iColumn = -1;
-      }
-      iSortOrder = pIdx->aSortOrder[i];
-      zColl = pIdx->azColl[i];
-    }else{
-      iColumn = -1;
-      iSortOrder = 0;
-      zColl = pColl->zName;
-    }
-    if( pExpr->iColumn!=iColumn || sqlite3StrICmp(pColl->zName, zColl) ){
-      /* Term j of the ORDER BY clause does not match column i of the index */
-      if( i<nEqCol ){
-        /* If an index column that is constrained by == fails to match an
-        ** ORDER BY term, that is OK.  Just ignore that column of the index
-        */
-        continue;
-      }else if( i==pIdx->nColumn ){
-        /* Index column i is the rowid.  All other terms match. */
-        break;
-      }else{
-        /* If an index column fails to match and is not constrained by ==
-        ** then the index cannot satisfy the ORDER BY constraint.
-        */
-        return 0;
-      }
-    }
-    assert( pIdx->aSortOrder!=0 || iColumn==-1 );
-    assert( pTerm->sortOrder==0 || pTerm->sortOrder==1 );
-    assert( iSortOrder==0 || iSortOrder==1 );
-    termSortOrder = iSortOrder ^ pTerm->sortOrder;
-    if( i>nEqCol ){
-      if( termSortOrder!=sortOrder ){
-        /* Indices can only be used if all ORDER BY terms past the
-        ** equality constraints are all either DESC or ASC. */
-        return 0;
-      }
-    }else{
-      sortOrder = termSortOrder;
-    }
-    j++;
-    pTerm++;
-    if( iColumn<0 && !referencesOtherTables(pOrderBy, pMaskSet, j, base) ){
-      /* If the indexed column is the primary key and everything matches
-      ** so far and none of the ORDER BY terms to the right reference other
-      ** tables in the join, then we are assured that the index can be used 
-      ** to sort because the primary key is unique and so none of the other
-      ** columns will make any difference
-      */
-      j = nTerm;
-    }
+static WhereCost whereCostAdd(WhereCost a, WhereCost b){
+  static const unsigned char x[] = {
+     10, 10,                         /* 0,1 */
+      9, 9,                          /* 2,3 */
+      8, 8,                          /* 4,5 */
+      7, 7, 7,                       /* 6,7,8 */
+      6, 6, 6,                       /* 9,10,11 */
+      5, 5, 5,                       /* 12-14 */
+      4, 4, 4, 4,                    /* 15-18 */
+      3, 3, 3, 3, 3, 3,              /* 19-24 */
+      2, 2, 2, 2, 2, 2, 2,           /* 25-31 */
+  };
+  if( a>=b ){
+    if( a>b+49 ) return a;
+    if( a>b+31 ) return a+1;
+    return a+x[a-b];
+  }else{
+    if( b>a+49 ) return b;
+    if( b>a+31 ) return b+1;
+    return b+x[b-a];
   }
-
-  *pbRev = sortOrder!=0;
-  if( j>=nTerm ){
-    /* All terms of the ORDER BY clause are covered by this index so
-    ** this index can be used for sorting. */
-    return 1;
-  }
-  if( pIdx->onError!=OE_None && i==pIdx->nColumn
-      && (wsFlags & WHERE_COLUMN_NULL)==0
-      && !referencesOtherTables(pOrderBy, pMaskSet, j, base) 
-  ){
-    Column *aCol = pIdx->pTable->aCol;
-
-    /* All terms of this index match some prefix of the ORDER BY clause,
-    ** the index is UNIQUE, and no terms on the tail of the ORDER BY
-    ** refer to other tables in a join. So, assuming that the index entries
-    ** visited contain no NULL values, then this index delivers rows in
-    ** the required order.
-    **
-    ** It is not possible for any of the first nEqCol index fields to be
-    ** NULL (since the corresponding "=" operator in the WHERE clause would 
-    ** not be true). So if all remaining index columns have NOT NULL 
-    ** constaints attached to them, we can be confident that the visited
-    ** index entries are free of NULLs.  */
-    for(i=nEqCol; i<pIdx->nColumn; i++){
-      if( aCol[pIdx->aiColumn[i]].notNull==0 ) break;
-    }
-    return (i==pIdx->nColumn);
-  }
-  return 0;
 }
 
 /*
-** Prepare a crude estimate of the logarithm of the input value.
-** The results need not be exact.  This is only used for estimating
-** the total cost of performing operations with O(logN) or O(NlogN)
-** complexity.  Because N is just a guess, it is no great tragedy if
-** logN is a little off.
+** Convert an integer into a WhereCost.  In other words, compute a
+** good approximatation for 10*log2(x).
 */
-static double estLog(double N){
-  double logN = 1;
-  double x = 10;
-  while( N>x ){
-    logN += 1;
-    x *= 10;
+static WhereCost whereCost(tRowcnt x){
+  static WhereCost a[] = { 0, 2, 3, 5, 6, 7, 8, 9 };
+  WhereCost y = 40;
+  if( x<8 ){
+    if( x<2 ) return 0;
+    while( x<8 ){  y -= 10; x <<= 1; }
+  }else{
+    while( x>255 ){ y += 40; x >>= 4; }
+    while( x>15 ){  y += 10; x >>= 1; }
   }
-  return logN;
+  return a[x&7] + y - 10;
+}
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/*
+** Convert a double (as received from xBestIndex of a virtual table)
+** into a WhereCost.  In other words, compute an approximation for
+** 10*log2(x).
+*/
+static WhereCost whereCostFromDouble(double x){
+  u64 a;
+  WhereCost e;
+  assert( sizeof(x)==8 && sizeof(a)==8 );
+  if( x<=1 ) return 0;
+  if( x<=2000000000 ) return whereCost((tRowcnt)x);
+  memcpy(&a, &x, 8);
+  e = (a>>52) - 1022;
+  return e*10;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+
+/*
+** Estimate the logarithm of the input value to base 2.
+*/
+static WhereCost estLog(WhereCost N){
+  WhereCost x = whereCost(N);
+  return x>33 ? x - 33 : 0;
 }
 
 /*
@@ -105428,7 +106771,7 @@ static double estLog(double N){
 ** SQLITE_TEST or SQLITE_DEBUG are defined, then these routines
 ** are no-ops.
 */
-#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_DEBUG)
+#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(WHERETRACE_ENABLED)
 static void TRACE_IDX_INPUTS(sqlite3_index_info *p){
   int i;
   if( !sqlite3WhereTrace ) return;
@@ -105466,109 +106809,6 @@ static void TRACE_IDX_OUTPUTS(sqlite3_index_info *p){
 #define TRACE_IDX_OUTPUTS(A)
 #endif
 
-/* 
-** Required because bestIndex() is called by bestOrClauseIndex() 
-*/
-static void bestIndex(
-    Parse*, WhereClause*, struct SrcList_item*,
-    Bitmask, Bitmask, ExprList*, WhereCost*);
-
-/*
-** This routine attempts to find an scanning strategy that can be used 
-** to optimize an 'OR' expression that is part of a WHERE clause. 
-**
-** The table associated with FROM clause term pSrc may be either a
-** regular B-Tree table or a virtual table.
-*/
-static void bestOrClauseIndex(
-  Parse *pParse,              /* The parsing context */
-  WhereClause *pWC,           /* The WHERE clause */
-  struct SrcList_item *pSrc,  /* The FROM clause term to search */
-  Bitmask notReady,           /* Mask of cursors not available for indexing */
-  Bitmask notValid,           /* Cursors not available for any purpose */
-  ExprList *pOrderBy,         /* The ORDER BY clause */
-  WhereCost *pCost            /* Lowest cost query plan */
-){
-#ifndef SQLITE_OMIT_OR_OPTIMIZATION
-  const int iCur = pSrc->iCursor;   /* The cursor of the table to be accessed */
-  const Bitmask maskSrc = getMask(pWC->pMaskSet, iCur);  /* Bitmask for pSrc */
-  WhereTerm * const pWCEnd = &pWC->a[pWC->nTerm];        /* End of pWC->a[] */
-  WhereTerm *pTerm;                 /* A single term of the WHERE clause */
-
-  /* The OR-clause optimization is disallowed if the INDEXED BY or
-  ** NOT INDEXED clauses are used or if the WHERE_AND_ONLY bit is set. */
-  if( pSrc->notIndexed || pSrc->pIndex!=0 ){
-    return;
-  }
-  if( pWC->wctrlFlags & WHERE_AND_ONLY ){
-    return;
-  }
-
-  /* Search the WHERE clause terms for a usable WO_OR term. */
-  for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){
-    if( pTerm->eOperator==WO_OR 
-     && ((pTerm->prereqAll & ~maskSrc) & notReady)==0
-     && (pTerm->u.pOrInfo->indexable & maskSrc)!=0 
-    ){
-      WhereClause * const pOrWC = &pTerm->u.pOrInfo->wc;
-      WhereTerm * const pOrWCEnd = &pOrWC->a[pOrWC->nTerm];
-      WhereTerm *pOrTerm;
-      int flags = WHERE_MULTI_OR;
-      double rTotal = 0;
-      double nRow = 0;
-      Bitmask used = 0;
-
-      for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){
-        WhereCost sTermCost;
-        WHERETRACE(("... Multi-index OR testing for term %d of %d....\n", 
-          (pOrTerm - pOrWC->a), (pTerm - pWC->a)
-        ));
-        if( pOrTerm->eOperator==WO_AND ){
-          WhereClause *pAndWC = &pOrTerm->u.pAndInfo->wc;
-          bestIndex(pParse, pAndWC, pSrc, notReady, notValid, 0, &sTermCost);
-        }else if( pOrTerm->leftCursor==iCur ){
-          WhereClause tempWC;
-          tempWC.pParse = pWC->pParse;
-          tempWC.pMaskSet = pWC->pMaskSet;
-          tempWC.pOuter = pWC;
-          tempWC.op = TK_AND;
-          tempWC.a = pOrTerm;
-          tempWC.wctrlFlags = 0;
-          tempWC.nTerm = 1;
-          bestIndex(pParse, &tempWC, pSrc, notReady, notValid, 0, &sTermCost);
-        }else{
-          continue;
-        }
-        rTotal += sTermCost.rCost;
-        nRow += sTermCost.plan.nRow;
-        used |= sTermCost.used;
-        if( rTotal>=pCost->rCost ) break;
-      }
-
-      /* If there is an ORDER BY clause, increase the scan cost to account 
-      ** for the cost of the sort. */
-      if( pOrderBy!=0 ){
-        WHERETRACE(("... sorting increases OR cost %.9g to %.9g\n",
-                    rTotal, rTotal+nRow*estLog(nRow)));
-        rTotal += nRow*estLog(nRow);
-      }
-
-      /* If the cost of scanning using this OR term for optimization is
-      ** less than the current cost stored in pCost, replace the contents
-      ** of pCost. */
-      WHERETRACE(("... multi-index OR cost=%.9g nrow=%.9g\n", rTotal, nRow));
-      if( rTotal<pCost->rCost ){
-        pCost->rCost = rTotal;
-        pCost->used = used;
-        pCost->plan.nRow = nRow;
-        pCost->plan.wsFlags = flags;
-        pCost->plan.u.pTerm = pTerm;
-      }
-    }
-  }
-#endif /* SQLITE_OMIT_OR_OPTIMIZATION */
-}
-
 #ifndef SQLITE_OMIT_AUTOMATIC_INDEX
 /*
 ** Return TRUE if the WHERE clause term pTerm is of a form where it
@@ -105582,87 +106822,15 @@ static int termCanDriveIndex(
 ){
   char aff;
   if( pTerm->leftCursor!=pSrc->iCursor ) return 0;
-  if( pTerm->eOperator!=WO_EQ ) return 0;
+  if( (pTerm->eOperator & WO_EQ)==0 ) return 0;
   if( (pTerm->prereqRight & notReady)!=0 ) return 0;
+  if( pTerm->u.leftColumn<0 ) return 0;
   aff = pSrc->pTab->aCol[pTerm->u.leftColumn].affinity;
   if( !sqlite3IndexAffinityOk(pTerm->pExpr, aff) ) return 0;
   return 1;
 }
 #endif
 
-#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
-/*
-** If the query plan for pSrc specified in pCost is a full table scan
-** and indexing is allows (if there is no NOT INDEXED clause) and it
-** possible to construct a transient index that would perform better
-** than a full table scan even when the cost of constructing the index
-** is taken into account, then alter the query plan to use the
-** transient index.
-*/
-static void bestAutomaticIndex(
-  Parse *pParse,              /* The parsing context */
-  WhereClause *pWC,           /* The WHERE clause */
-  struct SrcList_item *pSrc,  /* The FROM clause term to search */
-  Bitmask notReady,           /* Mask of cursors that are not available */
-  WhereCost *pCost            /* Lowest cost query plan */
-){
-  double nTableRow;           /* Rows in the input table */
-  double logN;                /* log(nTableRow) */
-  double costTempIdx;         /* per-query cost of the transient index */
-  WhereTerm *pTerm;           /* A single term of the WHERE clause */
-  WhereTerm *pWCEnd;          /* End of pWC->a[] */
-  Table *pTable;              /* Table tht might be indexed */
-
-  if( pParse->nQueryLoop<=(double)1 ){
-    /* There is no point in building an automatic index for a single scan */
-    return;
-  }
-  if( (pParse->db->flags & SQLITE_AutoIndex)==0 ){
-    /* Automatic indices are disabled at run-time */
-    return;
-  }
-  if( (pCost->plan.wsFlags & WHERE_NOT_FULLSCAN)!=0 ){
-    /* We already have some kind of index in use for this query. */
-    return;
-  }
-  if( pSrc->notIndexed ){
-    /* The NOT INDEXED clause appears in the SQL. */
-    return;
-  }
-  if( pSrc->isCorrelated ){
-    /* The source is a correlated sub-query. No point in indexing it. */
-    return;
-  }
-
-  assert( pParse->nQueryLoop >= (double)1 );
-  pTable = pSrc->pTab;
-  nTableRow = pTable->nRowEst;
-  logN = estLog(nTableRow);
-  costTempIdx = 2*logN*(nTableRow/pParse->nQueryLoop + 1);
-  if( costTempIdx>=pCost->rCost ){
-    /* The cost of creating the transient table would be greater than
-    ** doing the full table scan */
-    return;
-  }
-
-  /* Search for any equality comparison term */
-  pWCEnd = &pWC->a[pWC->nTerm];
-  for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){
-    if( termCanDriveIndex(pTerm, pSrc, notReady) ){
-      WHERETRACE(("auto-index reduces cost from %.1f to %.1f\n",
-                    pCost->rCost, costTempIdx));
-      pCost->rCost = costTempIdx;
-      pCost->plan.nRow = logN + 1;
-      pCost->plan.wsFlags = WHERE_TEMP_INDEX;
-      pCost->used = pTerm->prereqRight;
-      break;
-    }
-  }
-}
-#else
-# define bestAutomaticIndex(A,B,C,D,E)  /* no-op */
-#endif /* SQLITE_OMIT_AUTOMATIC_INDEX */
-
 
 #ifndef SQLITE_OMIT_AUTOMATIC_INDEX
 /*
@@ -105692,8 +106860,10 @@ static void constructAutomaticIndex(
   int i;                      /* Loop counter */
   int mxBitCol;               /* Maximum column in pSrc->colUsed */
   CollSeq *pColl;             /* Collating sequence to on a column */
+  WhereLoop *pLoop;           /* The Loop object */
   Bitmask idxCols;            /* Bitmap of columns used for indexing */
   Bitmask extraCols;          /* Bitmap of additional columns */
+  u8 sentWarning = 0;         /* True if a warnning has been issued */
 
   /* Generate code to skip over the creation and initialization of the
   ** transient index on 2nd and subsequent iterations of the loop. */
@@ -105706,21 +106876,31 @@ static void constructAutomaticIndex(
   nColumn = 0;
   pTable = pSrc->pTab;
   pWCEnd = &pWC->a[pWC->nTerm];
+  pLoop = pLevel->pWLoop;
   idxCols = 0;
   for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){
     if( termCanDriveIndex(pTerm, pSrc, notReady) ){
       int iCol = pTerm->u.leftColumn;
-      Bitmask cMask = iCol>=BMS ? ((Bitmask)1)<<(BMS-1) : ((Bitmask)1)<<iCol;
+      Bitmask cMask = iCol>=BMS ? MASKBIT(BMS-1) : MASKBIT(iCol);
       testcase( iCol==BMS );
       testcase( iCol==BMS-1 );
+      if( !sentWarning ){
+        sqlite3_log(SQLITE_WARNING_AUTOINDEX,
+            "automatic index on %s(%s)", pTable->zName,
+            pTable->aCol[iCol].zName);
+        sentWarning = 1;
+      }
       if( (idxCols & cMask)==0 ){
-        nColumn++;
+        if( whereLoopResize(pParse->db, pLoop, nColumn+1) ) return;
+        pLoop->aLTerm[nColumn++] = pTerm;
         idxCols |= cMask;
       }
     }
   }
   assert( nColumn>0 );
-  pLevel->plan.nEq = nColumn;
+  pLoop->u.btree.nEq = pLoop->nLTerm = nColumn;
+  pLoop->wsFlags = WHERE_COLUMN_EQ | WHERE_IDX_ONLY | WHERE_INDEXED
+                     | WHERE_AUTO_INDEX;
 
   /* Count the number of additional columns needed to create a
   ** covering index.  A "covering index" is an index that contains all
@@ -105730,17 +106910,17 @@ static void constructAutomaticIndex(
   ** original table changes and the index and table cannot both be used
   ** if they go out of sync.
   */
-  extraCols = pSrc->colUsed & (~idxCols | (((Bitmask)1)<<(BMS-1)));
+  extraCols = pSrc->colUsed & (~idxCols | MASKBIT(BMS-1));
   mxBitCol = (pTable->nCol >= BMS-1) ? BMS-1 : pTable->nCol;
   testcase( pTable->nCol==BMS-1 );
   testcase( pTable->nCol==BMS-2 );
   for(i=0; i<mxBitCol; i++){
-    if( extraCols & (((Bitmask)1)<<i) ) nColumn++;
+    if( extraCols & MASKBIT(i) ) nColumn++;
   }
-  if( pSrc->colUsed & (((Bitmask)1)<<(BMS-1)) ){
+  if( pSrc->colUsed & MASKBIT(BMS-1) ){
     nColumn += pTable->nCol - BMS + 1;
   }
-  pLevel->plan.wsFlags |= WHERE_COLUMN_EQ | WHERE_IDX_ONLY | WO_EQ;
+  pLoop->wsFlags |= WHERE_COLUMN_EQ | WHERE_IDX_ONLY;
 
   /* Construct the Index object to describe this index */
   nByte = sizeof(Index);
@@ -105749,7 +106929,7 @@ static void constructAutomaticIndex(
   nByte += nColumn;                 /* Index.aSortOrder */
   pIdx = sqlite3DbMallocZero(pParse->db, nByte);
   if( pIdx==0 ) return;
-  pLevel->plan.u.pIdx = pIdx;
+  pLoop->u.btree.pIndex = pIdx;
   pIdx->azColl = (char**)&pIdx[1];
   pIdx->aiColumn = (int*)&pIdx->azColl[nColumn];
   pIdx->aSortOrder = (u8*)&pIdx->aiColumn[nColumn];
@@ -105761,7 +106941,9 @@ static void constructAutomaticIndex(
   for(pTerm=pWC->a; pTerm<pWCEnd; pTerm++){
     if( termCanDriveIndex(pTerm, pSrc, notReady) ){
       int iCol = pTerm->u.leftColumn;
-      Bitmask cMask = iCol>=BMS ? ((Bitmask)1)<<(BMS-1) : ((Bitmask)1)<<iCol;
+      Bitmask cMask = iCol>=BMS ? MASKBIT(BMS-1) : MASKBIT(iCol);
+      testcase( iCol==BMS-1 );
+      testcase( iCol==BMS );
       if( (idxCols & cMask)==0 ){
         Expr *pX = pTerm->pExpr;
         idxCols |= cMask;
@@ -105772,18 +106954,18 @@ static void constructAutomaticIndex(
       }
     }
   }
-  assert( (u32)n==pLevel->plan.nEq );
+  assert( (u32)n==pLoop->u.btree.nEq );
 
   /* Add additional columns needed to make the automatic index into
   ** a covering index */
   for(i=0; i<mxBitCol; i++){
-    if( extraCols & (((Bitmask)1)<<i) ){
+    if( extraCols & MASKBIT(i) ){
       pIdx->aiColumn[n] = i;
       pIdx->azColl[n] = "BINARY";
       n++;
     }
   }
-  if( pSrc->colUsed & (((Bitmask)1)<<(BMS-1)) ){
+  if( pSrc->colUsed & MASKBIT(BMS-1) ){
     for(i=BMS-1; i<pTable->nCol; i++){
       pIdx->aiColumn[n] = i;
       pIdx->azColl[n] = "BINARY";
@@ -105795,6 +106977,7 @@ static void constructAutomaticIndex(
   /* Create the automatic index */
   pKeyinfo = sqlite3IndexKeyinfo(pParse, pIdx);
   assert( pLevel->iIdxCur>=0 );
+  pLevel->iIdxCur = pParse->nTab++;
   sqlite3VdbeAddOp4(v, OP_OpenAutoindex, pLevel->iIdxCur, nColumn+1, 0,
                     (char*)pKeyinfo, P4_KEYINFO_HANDOFF);
   VdbeComment((v, "for %s", pTable->zName));
@@ -105802,7 +106985,7 @@ static void constructAutomaticIndex(
   /* Fill the automatic index with content */
   addrTop = sqlite3VdbeAddOp1(v, OP_Rewind, pLevel->iTabCur);
   regRecord = sqlite3GetTempReg(pParse);
-  sqlite3GenerateIndexKey(pParse, pIdx, pLevel->iTabCur, regRecord, 1);
+  sqlite3GenerateIndexKey(pParse, pIdx, pLevel->iTabCur, regRecord, 1, 0);
   sqlite3VdbeAddOp2(v, OP_IdxInsert, pLevel->iIdxCur, regRecord);
   sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
   sqlite3VdbeAddOp2(v, OP_Next, pLevel->iTabCur, addrTop+1);
@@ -105822,7 +107005,7 @@ static void constructAutomaticIndex(
 ** by passing the pointer returned by this function to sqlite3_free().
 */
 static sqlite3_index_info *allocateIndexInfo(
-  Parse *pParse, 
+  Parse *pParse,
   WhereClause *pWC,
   struct SrcList_item *pSrc,
   ExprList *pOrderBy
@@ -105836,16 +107019,14 @@ static sqlite3_index_info *allocateIndexInfo(
   int nOrderBy;
   sqlite3_index_info *pIdxInfo;
 
-  WHERETRACE(("Recomputing index info for %s...\n", pSrc->pTab->zName));
-
   /* Count the number of possible WHERE clause constraints referring
   ** to this virtual table */
   for(i=nTerm=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
     if( pTerm->leftCursor != pSrc->iCursor ) continue;
-    assert( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
-    testcase( pTerm->eOperator==WO_IN );
-    testcase( pTerm->eOperator==WO_ISNULL );
-    if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
+    assert( IsPowerOfTwo(pTerm->eOperator & ~WO_EQUIV) );
+    testcase( pTerm->eOperator & WO_IN );
+    testcase( pTerm->eOperator & WO_ISNULL );
+    if( pTerm->eOperator & (WO_ISNULL) ) continue;
     if( pTerm->wtFlags & TERM_VNULL ) continue;
     nTerm++;
   }
@@ -105856,12 +107037,13 @@ static sqlite3_index_info *allocateIndexInfo(
   */
   nOrderBy = 0;
   if( pOrderBy ){
-    for(i=0; i<pOrderBy->nExpr; i++){
+    int n = pOrderBy->nExpr;
+    for(i=0; i<n; i++){
       Expr *pExpr = pOrderBy->a[i].pExpr;
       if( pExpr->op!=TK_COLUMN || pExpr->iTable!=pSrc->iCursor ) break;
     }
-    if( i==pOrderBy->nExpr ){
-      nOrderBy = pOrderBy->nExpr;
+    if( i==n){
+      nOrderBy = n;
     }
   }
 
@@ -105872,7 +107054,6 @@ static sqlite3_index_info *allocateIndexInfo(
                            + sizeof(*pIdxOrderBy)*nOrderBy );
   if( pIdxInfo==0 ){
     sqlite3ErrorMsg(pParse, "out of memory");
-    /* (double)0 In case of SQLITE_OMIT_FLOATING_POINT... */
     return 0;
   }
 
@@ -105892,15 +107073,18 @@ static sqlite3_index_info *allocateIndexInfo(
                                                                    pUsage;
 
   for(i=j=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
+    u8 op;
     if( pTerm->leftCursor != pSrc->iCursor ) continue;
-    assert( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
-    testcase( pTerm->eOperator==WO_IN );
-    testcase( pTerm->eOperator==WO_ISNULL );
-    if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
+    assert( IsPowerOfTwo(pTerm->eOperator & ~WO_EQUIV) );
+    testcase( pTerm->eOperator & WO_IN );
+    testcase( pTerm->eOperator & WO_ISNULL );
+    if( pTerm->eOperator & (WO_ISNULL) ) continue;
     if( pTerm->wtFlags & TERM_VNULL ) continue;
     pIdxCons[j].iColumn = pTerm->u.leftColumn;
     pIdxCons[j].iTermOffset = i;
-    pIdxCons[j].op = (u8)pTerm->eOperator;
+    op = (u8)pTerm->eOperator & WO_ALL;
+    if( op==WO_IN ) op = WO_EQ;
+    pIdxCons[j].op = op;
     /* The direct assignment in the previous line is possible only because
     ** the WO_ and SQLITE_INDEX_CONSTRAINT_ codes are identical.  The
     ** following asserts verify this fact. */
@@ -105910,7 +107094,7 @@ static sqlite3_index_info *allocateIndexInfo(
     assert( WO_GT==SQLITE_INDEX_CONSTRAINT_GT );
     assert( WO_GE==SQLITE_INDEX_CONSTRAINT_GE );
     assert( WO_MATCH==SQLITE_INDEX_CONSTRAINT_MATCH );
-    assert( pTerm->eOperator & (WO_EQ|WO_LT|WO_LE|WO_GT|WO_GE|WO_MATCH) );
+    assert( pTerm->eOperator & (WO_IN|WO_EQ|WO_LT|WO_LE|WO_GT|WO_GE|WO_MATCH) );
     j++;
   }
   for(i=0; i<nOrderBy; i++){
@@ -105925,8 +107109,8 @@ static sqlite3_index_info *allocateIndexInfo(
 /*
 ** The table object reference passed as the second argument to this function
 ** must represent a virtual table. This function invokes the xBestIndex()
-** method of the virtual table with the sqlite3_index_info pointer passed
-** as the argument.
+** method of the virtual table with the sqlite3_index_info object that
+** comes in as the 3rd argument to this function.
 **
 ** If an error occurs, pParse is populated with an error message and a
 ** non-zero value is returned. Otherwise, 0 is returned and the output
@@ -105941,7 +107125,6 @@ static int vtabBestIndex(Parse *pParse, Table *pTab, sqlite3_index_info *p){
   int i;
   int rc;
 
-  WHERETRACE(("xBestIndex for %s\n", pTab->zName));
   TRACE_IDX_INPUTS(p);
   rc = pVtab->pModule->xBestIndex(pVtab, p);
   TRACE_IDX_OUTPUTS(p);
@@ -105967,163 +107150,9 @@ static int vtabBestIndex(Parse *pParse, Table *pTab, sqlite3_index_info *p){
 
   return pParse->nErr;
 }
+#endif /* !defined(SQLITE_OMIT_VIRTUALTABLE) */
 
 
-/*
-** Compute the best index for a virtual table.
-**
-** The best index is computed by the xBestIndex method of the virtual
-** table module.  This routine is really just a wrapper that sets up
-** the sqlite3_index_info structure that is used to communicate with
-** xBestIndex.
-**
-** In a join, this routine might be called multiple times for the
-** same virtual table.  The sqlite3_index_info structure is created
-** and initialized on the first invocation and reused on all subsequent
-** invocations.  The sqlite3_index_info structure is also used when
-** code is generated to access the virtual table.  The whereInfoDelete() 
-** routine takes care of freeing the sqlite3_index_info structure after
-** everybody has finished with it.
-*/
-static void bestVirtualIndex(
-  Parse *pParse,                  /* The parsing context */
-  WhereClause *pWC,               /* The WHERE clause */
-  struct SrcList_item *pSrc,      /* The FROM clause term to search */
-  Bitmask notReady,               /* Mask of cursors not available for index */
-  Bitmask notValid,               /* Cursors not valid for any purpose */
-  ExprList *pOrderBy,             /* The order by clause */
-  WhereCost *pCost,               /* Lowest cost query plan */
-  sqlite3_index_info **ppIdxInfo  /* Index information passed to xBestIndex */
-){
-  Table *pTab = pSrc->pTab;
-  sqlite3_index_info *pIdxInfo;
-  struct sqlite3_index_constraint *pIdxCons;
-  struct sqlite3_index_constraint_usage *pUsage;
-  WhereTerm *pTerm;
-  int i, j;
-  int nOrderBy;
-  double rCost;
-
-  /* Make sure wsFlags is initialized to some sane value. Otherwise, if the 
-  ** malloc in allocateIndexInfo() fails and this function returns leaving
-  ** wsFlags in an uninitialized state, the caller may behave unpredictably.
-  */
-  memset(pCost, 0, sizeof(*pCost));
-  pCost->plan.wsFlags = WHERE_VIRTUALTABLE;
-
-  /* If the sqlite3_index_info structure has not been previously
-  ** allocated and initialized, then allocate and initialize it now.
-  */
-  pIdxInfo = *ppIdxInfo;
-  if( pIdxInfo==0 ){
-    *ppIdxInfo = pIdxInfo = allocateIndexInfo(pParse, pWC, pSrc, pOrderBy);
-  }
-  if( pIdxInfo==0 ){
-    return;
-  }
-
-  /* At this point, the sqlite3_index_info structure that pIdxInfo points
-  ** to will have been initialized, either during the current invocation or
-  ** during some prior invocation.  Now we just have to customize the
-  ** details of pIdxInfo for the current invocation and pass it to
-  ** xBestIndex.
-  */
-
-  /* The module name must be defined. Also, by this point there must
-  ** be a pointer to an sqlite3_vtab structure. Otherwise
-  ** sqlite3ViewGetColumnNames() would have picked up the error. 
-  */
-  assert( pTab->azModuleArg && pTab->azModuleArg[0] );
-  assert( sqlite3GetVTable(pParse->db, pTab) );
-
-  /* Set the aConstraint[].usable fields and initialize all 
-  ** output variables to zero.
-  **
-  ** aConstraint[].usable is true for constraints where the right-hand
-  ** side contains only references to tables to the left of the current
-  ** table.  In other words, if the constraint is of the form:
-  **
-  **           column = expr
-  **
-  ** and we are evaluating a join, then the constraint on column is 
-  ** only valid if all tables referenced in expr occur to the left
-  ** of the table containing column.
-  **
-  ** The aConstraints[] array contains entries for all constraints
-  ** on the current table.  That way we only have to compute it once
-  ** even though we might try to pick the best index multiple times.
-  ** For each attempt at picking an index, the order of tables in the
-  ** join might be different so we have to recompute the usable flag
-  ** each time.
-  */
-  pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
-  pUsage = pIdxInfo->aConstraintUsage;
-  for(i=0; i<pIdxInfo->nConstraint; i++, pIdxCons++){
-    j = pIdxCons->iTermOffset;
-    pTerm = &pWC->a[j];
-    pIdxCons->usable = (pTerm->prereqRight&notReady) ? 0 : 1;
-  }
-  memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
-  if( pIdxInfo->needToFreeIdxStr ){
-    sqlite3_free(pIdxInfo->idxStr);
-  }
-  pIdxInfo->idxStr = 0;
-  pIdxInfo->idxNum = 0;
-  pIdxInfo->needToFreeIdxStr = 0;
-  pIdxInfo->orderByConsumed = 0;
-  /* ((double)2) In case of SQLITE_OMIT_FLOATING_POINT... */
-  pIdxInfo->estimatedCost = SQLITE_BIG_DBL / ((double)2);
-  nOrderBy = pIdxInfo->nOrderBy;
-  if( !pOrderBy ){
-    pIdxInfo->nOrderBy = 0;
-  }
-
-  if( vtabBestIndex(pParse, pTab, pIdxInfo) ){
-    return;
-  }
-
-  pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
-  for(i=0; i<pIdxInfo->nConstraint; i++){
-    if( pUsage[i].argvIndex>0 ){
-      pCost->used |= pWC->a[pIdxCons[i].iTermOffset].prereqRight;
-    }
-  }
-
-  /* If there is an ORDER BY clause, and the selected virtual table index
-  ** does not satisfy it, increase the cost of the scan accordingly. This
-  ** matches the processing for non-virtual tables in bestBtreeIndex().
-  */
-  rCost = pIdxInfo->estimatedCost;
-  if( pOrderBy && pIdxInfo->orderByConsumed==0 ){
-    rCost += estLog(rCost)*rCost;
-  }
-
-  /* The cost is not allowed to be larger than SQLITE_BIG_DBL (the
-  ** inital value of lowestCost in this loop. If it is, then the
-  ** (cost<lowestCost) test below will never be true.
-  ** 
-  ** Use "(double)2" instead of "2.0" in case OMIT_FLOATING_POINT 
-  ** is defined.
-  */
-  if( (SQLITE_BIG_DBL/((double)2))<rCost ){
-    pCost->rCost = (SQLITE_BIG_DBL/((double)2));
-  }else{
-    pCost->rCost = rCost;
-  }
-  pCost->plan.u.pVtabIdx = pIdxInfo;
-  if( pIdxInfo->orderByConsumed ){
-    pCost->plan.wsFlags |= WHERE_ORDERBY;
-  }
-  pCost->plan.nEq = 0;
-  pIdxInfo->nOrderBy = nOrderBy;
-
-  /* Try to find a more efficient access pattern by using multiple indexes
-  ** to optimize an OR expression within the WHERE clause. 
-  */
-  bestOrClauseIndex(pParse, pWC, pSrc, notReady, notValid, pOrderBy, pCost);
-}
-#endif /* SQLITE_OMIT_VIRTUALTABLE */
-
 #ifdef SQLITE_ENABLE_STAT3
 /*
 ** Estimate the location of a particular key among all keys in an
@@ -106208,12 +107237,11 @@ static int whereKeyStats(
         pColl = db->pDfltColl;
         assert( pColl->enc==SQLITE_UTF8 );
       }else{
-        pColl = sqlite3GetCollSeq(db, SQLITE_UTF8, 0, *pIdx->azColl);
-        if( pColl==0 ){
-          sqlite3ErrorMsg(pParse, "no such collation sequence: %s",
-                          *pIdx->azColl);
-          return SQLITE_ERROR;
-        }
+        pColl = sqlite3GetCollSeq(pParse, SQLITE_UTF8, 0, *pIdx->azColl);
+        /* If the collating sequence was unavailable, we should have failed
+        ** long ago and never reached this point.  But we'll check just to
+        ** be doubly sure. */
+        if( NEVER(pColl==0) ) return SQLITE_ERROR;
         z = (const u8 *)sqlite3ValueText(pVal, pColl->enc);
         if( !z ){
           return SQLITE_NOMEM;
@@ -106314,7 +107342,7 @@ static int valueFromExpr(
   ){
     int iVar = pExpr->iColumn;
     sqlite3VdbeSetVarmask(pParse->pVdbe, iVar);
-    *pp = sqlite3VdbeGetValue(pParse->pReprepare, iVar, aff);
+    *pp = sqlite3VdbeGetBoundValue(pParse->pReprepare, iVar, aff);
     return SQLITE_OK;
   }
   return sqlite3ValueFromExpr(pParse->db, pExpr, SQLITE_UTF8, aff, pp);
@@ -106366,13 +107394,13 @@ static int whereRangeScanEst(
   int nEq,             /* index into p->aCol[] of the range-compared column */
   WhereTerm *pLower,   /* Lower bound on the range. ex: "x>123" Might be NULL */
   WhereTerm *pUpper,   /* Upper bound on the range. ex: "x<455" Might be NULL */
-  double *pRangeDiv   /* OUT: Reduce search space by this divisor */
+  WhereCost *pRangeDiv /* OUT: Reduce search space by this divisor */
 ){
   int rc = SQLITE_OK;
 
 #ifdef SQLITE_ENABLE_STAT3
 
-  if( nEq==0 && p->nSample ){
+  if( nEq==0 && p->nSample && OptimizationEnabled(pParse->db, SQLITE_Stat3) ){
     sqlite3_value *pRangeVal;
     tRowcnt iLower = 0;
     tRowcnt iUpper = p->aiRowEst[0];
@@ -106382,35 +107410,35 @@ static int whereRangeScanEst(
     if( pLower ){
       Expr *pExpr = pLower->pExpr->pRight;
       rc = valueFromExpr(pParse, pExpr, aff, &pRangeVal);
-      assert( pLower->eOperator==WO_GT || pLower->eOperator==WO_GE );
+      assert( (pLower->eOperator & (WO_GT|WO_GE))!=0 );
       if( rc==SQLITE_OK
        && whereKeyStats(pParse, p, pRangeVal, 0, a)==SQLITE_OK
       ){
         iLower = a[0];
-        if( pLower->eOperator==WO_GT ) iLower += a[1];
+        if( (pLower->eOperator & WO_GT)!=0 ) iLower += a[1];
       }
       sqlite3ValueFree(pRangeVal);
     }
     if( rc==SQLITE_OK && pUpper ){
       Expr *pExpr = pUpper->pExpr->pRight;
       rc = valueFromExpr(pParse, pExpr, aff, &pRangeVal);
-      assert( pUpper->eOperator==WO_LT || pUpper->eOperator==WO_LE );
+      assert( (pUpper->eOperator & (WO_LT|WO_LE))!=0 );
       if( rc==SQLITE_OK
        && whereKeyStats(pParse, p, pRangeVal, 1, a)==SQLITE_OK
       ){
         iUpper = a[0];
-        if( pUpper->eOperator==WO_LE ) iUpper += a[1];
+        if( (pUpper->eOperator & WO_LE)!=0 ) iUpper += a[1];
       }
       sqlite3ValueFree(pRangeVal);
     }
     if( rc==SQLITE_OK ){
-      if( iUpper<=iLower ){
-        *pRangeDiv = (double)p->aiRowEst[0];
-      }else{
-        *pRangeDiv = (double)p->aiRowEst[0]/(double)(iUpper - iLower);
+      WhereCost iBase = whereCost(p->aiRowEst[0]);
+      if( iUpper>iLower ){
+        iBase -= whereCost(iUpper - iLower);
       }
-      WHERETRACE(("range scan regions: %u..%u  div=%g\n",
-                  (u32)iLower, (u32)iUpper, *pRangeDiv));
+      *pRangeDiv = iBase;
+      WHERETRACE(0x100, ("range scan regions: %u..%u  div=%d\n",
+                         (u32)iLower, (u32)iUpper, *pRangeDiv));
       return SQLITE_OK;
     }
   }
@@ -106420,9 +107448,15 @@ static int whereRangeScanEst(
   UNUSED_PARAMETER(nEq);
 #endif
   assert( pLower || pUpper );
-  *pRangeDiv = (double)1;
-  if( pLower && (pLower->wtFlags & TERM_VNULL)==0 ) *pRangeDiv *= (double)4;
-  if( pUpper ) *pRangeDiv *= (double)4;
+  *pRangeDiv = 0;
+  /* TUNING:  Each inequality constraint reduces the search space 4-fold.
+  ** A BETWEEN operator, therefore, reduces the search space 16-fold */
+  if( pLower && (pLower->wtFlags & TERM_VNULL)==0 ){
+    *pRangeDiv += 20;  assert( 20==whereCost(4) );
+  }
+  if( pUpper ){
+    *pRangeDiv += 20;  assert( 20==whereCost(4) );
+  }
   return rc;
 }
 
@@ -106448,7 +107482,7 @@ static int whereEqualScanEst(
   Parse *pParse,       /* Parsing & code generating context */
   Index *p,            /* The index whose left-most column is pTerm */
   Expr *pExpr,         /* Expression for VALUE in the x=VALUE constraint */
-  double *pnRow        /* Write the revised row estimate here */
+  tRowcnt *pnRow       /* Write the revised row estimate here */
 ){
   sqlite3_value *pRhs = 0;  /* VALUE on right-hand side of pTerm */
   u8 aff;                   /* Column affinity */
@@ -106467,7 +107501,7 @@ static int whereEqualScanEst(
   if( pRhs==0 ) return SQLITE_NOTFOUND;
   rc = whereKeyStats(pParse, p, pRhs, 0, a);
   if( rc==SQLITE_OK ){
-    WHERETRACE(("equality scan regions: %d\n", (int)a[1]));
+    WHERETRACE(0x100,("equality scan regions: %d\n", (int)a[1]));
     *pnRow = a[1];
   }
 whereEqualScanEst_cancel:
@@ -106497,12 +107531,12 @@ static int whereInScanEst(
   Parse *pParse,       /* Parsing & code generating context */
   Index *p,            /* The index whose left-most column is pTerm */
   ExprList *pList,     /* The value list on the RHS of "x IN (v1,v2,v3,...)" */
-  double *pnRow        /* Write the revised row estimate here */
+  tRowcnt *pnRow       /* Write the revised row estimate here */
 ){
-  int rc = SQLITE_OK;         /* Subfunction return code */
-  double nEst;                /* Number of rows for a single term */
-  double nRowEst = (double)0; /* New estimate of the number of rows */
-  int i;                      /* Loop counter */
+  int rc = SQLITE_OK;     /* Subfunction return code */
+  tRowcnt nEst;           /* Number of rows for a single term */
+  tRowcnt nRowEst = 0;    /* New estimate of the number of rows */
+  int i;                  /* Loop counter */
 
   assert( p->aSample!=0 );
   for(i=0; rc==SQLITE_OK && i<pList->nExpr; i++){
@@ -106513,550 +107547,12 @@ static int whereInScanEst(
   if( rc==SQLITE_OK ){
     if( nRowEst > p->aiRowEst[0] ) nRowEst = p->aiRowEst[0];
     *pnRow = nRowEst;
-    WHERETRACE(("IN row estimate: est=%g\n", nRowEst));
+    WHERETRACE(0x100,("IN row estimate: est=%g\n", nRowEst));
   }
   return rc;
 }
 #endif /* defined(SQLITE_ENABLE_STAT3) */
 
-
-/*
-** Find the best query plan for accessing a particular table.  Write the
-** best query plan and its cost into the WhereCost object supplied as the
-** last parameter.
-**
-** The lowest cost plan wins.  The cost is an estimate of the amount of
-** CPU and disk I/O needed to process the requested result.
-** Factors that influence cost include:
-**
-**    *  The estimated number of rows that will be retrieved.  (The
-**       fewer the better.)
-**
-**    *  Whether or not sorting must occur.
-**
-**    *  Whether or not there must be separate lookups in the
-**       index and in the main table.
-**
-** If there was an INDEXED BY clause (pSrc->pIndex) attached to the table in
-** the SQL statement, then this function only considers plans using the 
-** named index. If no such plan is found, then the returned cost is
-** SQLITE_BIG_DBL. If a plan is found that uses the named index, 
-** then the cost is calculated in the usual way.
-**
-** If a NOT INDEXED clause (pSrc->notIndexed!=0) was attached to the table 
-** in the SELECT statement, then no indexes are considered. However, the 
-** selected plan may still take advantage of the built-in rowid primary key
-** index.
-*/
-static void bestBtreeIndex(
-  Parse *pParse,              /* The parsing context */
-  WhereClause *pWC,           /* The WHERE clause */
-  struct SrcList_item *pSrc,  /* The FROM clause term to search */
-  Bitmask notReady,           /* Mask of cursors not available for indexing */
-  Bitmask notValid,           /* Cursors not available for any purpose */
-  ExprList *pOrderBy,         /* The ORDER BY clause */
-  ExprList *pDistinct,        /* The select-list if query is DISTINCT */
-  WhereCost *pCost            /* Lowest cost query plan */
-){
-  int iCur = pSrc->iCursor;   /* The cursor of the table to be accessed */
-  Index *pProbe;              /* An index we are evaluating */
-  Index *pIdx;                /* Copy of pProbe, or zero for IPK index */
-  int eqTermMask;             /* Current mask of valid equality operators */
-  int idxEqTermMask;          /* Index mask of valid equality operators */
-  Index sPk;                  /* A fake index object for the primary key */
-  tRowcnt aiRowEstPk[2];      /* The aiRowEst[] value for the sPk index */
-  int aiColumnPk = -1;        /* The aColumn[] value for the sPk index */
-  int wsFlagMask;             /* Allowed flags in pCost->plan.wsFlag */
-
-  /* Initialize the cost to a worst-case value */
-  memset(pCost, 0, sizeof(*pCost));
-  pCost->rCost = SQLITE_BIG_DBL;
-
-  /* If the pSrc table is the right table of a LEFT JOIN then we may not
-  ** use an index to satisfy IS NULL constraints on that table.  This is
-  ** because columns might end up being NULL if the table does not match -
-  ** a circumstance which the index cannot help us discover.  Ticket #2177.
-  */
-  if( pSrc->jointype & JT_LEFT ){
-    idxEqTermMask = WO_EQ|WO_IN;
-  }else{
-    idxEqTermMask = WO_EQ|WO_IN|WO_ISNULL;
-  }
-
-  if( pSrc->pIndex ){
-    /* An INDEXED BY clause specifies a particular index to use */
-    pIdx = pProbe = pSrc->pIndex;
-    wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
-    eqTermMask = idxEqTermMask;
-  }else{
-    /* There is no INDEXED BY clause.  Create a fake Index object in local
-    ** variable sPk to represent the rowid primary key index.  Make this
-    ** fake index the first in a chain of Index objects with all of the real
-    ** indices to follow */
-    Index *pFirst;                  /* First of real indices on the table */
-    memset(&sPk, 0, sizeof(Index));
-    sPk.nColumn = 1;
-    sPk.aiColumn = &aiColumnPk;
-    sPk.aiRowEst = aiRowEstPk;
-    sPk.onError = OE_Replace;
-    sPk.pTable = pSrc->pTab;
-    aiRowEstPk[0] = pSrc->pTab->nRowEst;
-    aiRowEstPk[1] = 1;
-    pFirst = pSrc->pTab->pIndex;
-    if( pSrc->notIndexed==0 ){
-      /* The real indices of the table are only considered if the
-      ** NOT INDEXED qualifier is omitted from the FROM clause */
-      sPk.pNext = pFirst;
-    }
-    pProbe = &sPk;
-    wsFlagMask = ~(
-        WHERE_COLUMN_IN|WHERE_COLUMN_EQ|WHERE_COLUMN_NULL|WHERE_COLUMN_RANGE
-    );
-    eqTermMask = WO_EQ|WO_IN;
-    pIdx = 0;
-  }
-
-  /* Loop over all indices looking for the best one to use
-  */
-  for(; pProbe; pIdx=pProbe=pProbe->pNext){
-    const tRowcnt * const aiRowEst = pProbe->aiRowEst;
-    double cost;                /* Cost of using pProbe */
-    double nRow;                /* Estimated number of rows in result set */
-    double log10N = (double)1;  /* base-10 logarithm of nRow (inexact) */
-    int rev;                    /* True to scan in reverse order */
-    int wsFlags = 0;
-    Bitmask used = 0;
-
-    /* The following variables are populated based on the properties of
-    ** index being evaluated. They are then used to determine the expected
-    ** cost and number of rows returned.
-    **
-    **  nEq: 
-    **    Number of equality terms that can be implemented using the index.
-    **    In other words, the number of initial fields in the index that
-    **    are used in == or IN or NOT NULL constraints of the WHERE clause.
-    **
-    **  nInMul:  
-    **    The "in-multiplier". This is an estimate of how many seek operations 
-    **    SQLite must perform on the index in question. For example, if the 
-    **    WHERE clause is:
-    **
-    **      WHERE a IN (1, 2, 3) AND b IN (4, 5, 6)
-    **
-    **    SQLite must perform 9 lookups on an index on (a, b), so nInMul is 
-    **    set to 9. Given the same schema and either of the following WHERE 
-    **    clauses:
-    **
-    **      WHERE a =  1
-    **      WHERE a >= 2
-    **
-    **    nInMul is set to 1.
-    **
-    **    If there exists a WHERE term of the form "x IN (SELECT ...)", then 
-    **    the sub-select is assumed to return 25 rows for the purposes of 
-    **    determining nInMul.
-    **
-    **  bInEst:  
-    **    Set to true if there was at least one "x IN (SELECT ...)" term used 
-    **    in determining the value of nInMul.  Note that the RHS of the
-    **    IN operator must be a SELECT, not a value list, for this variable
-    **    to be true.
-    **
-    **  rangeDiv:
-    **    An estimate of a divisor by which to reduce the search space due
-    **    to inequality constraints.  In the absence of sqlite_stat3 ANALYZE
-    **    data, a single inequality reduces the search space to 1/4rd its
-    **    original size (rangeDiv==4).  Two inequalities reduce the search
-    **    space to 1/16th of its original size (rangeDiv==16).
-    **
-    **  bSort:   
-    **    Boolean. True if there is an ORDER BY clause that will require an 
-    **    external sort (i.e. scanning the index being evaluated will not 
-    **    correctly order records).
-    **
-    **  bLookup: 
-    **    Boolean. True if a table lookup is required for each index entry
-    **    visited.  In other words, true if this is not a covering index.
-    **    This is always false for the rowid primary key index of a table.
-    **    For other indexes, it is true unless all the columns of the table
-    **    used by the SELECT statement are present in the index (such an
-    **    index is sometimes described as a covering index).
-    **    For example, given the index on (a, b), the second of the following 
-    **    two queries requires table b-tree lookups in order to find the value
-    **    of column c, but the first does not because columns a and b are
-    **    both available in the index.
-    **
-    **             SELECT a, b    FROM tbl WHERE a = 1;
-    **             SELECT a, b, c FROM tbl WHERE a = 1;
-    */
-    int nEq;                      /* Number of == or IN terms matching index */
-    int bInEst = 0;               /* True if "x IN (SELECT...)" seen */
-    int nInMul = 1;               /* Number of distinct equalities to lookup */
-    double rangeDiv = (double)1;  /* Estimated reduction in search space */
-    int nBound = 0;               /* Number of range constraints seen */
-    int bSort = !!pOrderBy;       /* True if external sort required */
-    int bDist = !!pDistinct;      /* True if index cannot help with DISTINCT */
-    int bLookup = 0;              /* True if not a covering index */
-    WhereTerm *pTerm;             /* A single term of the WHERE clause */
-#ifdef SQLITE_ENABLE_STAT3
-    WhereTerm *pFirstTerm = 0;    /* First term matching the index */
-#endif
-
-    /* Determine the values of nEq and nInMul */
-    for(nEq=0; nEq<pProbe->nColumn; nEq++){
-      int j = pProbe->aiColumn[nEq];
-      pTerm = findTerm(pWC, iCur, j, notReady, eqTermMask, pIdx);
-      if( pTerm==0 ) break;
-      wsFlags |= (WHERE_COLUMN_EQ|WHERE_ROWID_EQ);
-      testcase( pTerm->pWC!=pWC );
-      if( pTerm->eOperator & WO_IN ){
-        Expr *pExpr = pTerm->pExpr;
-        wsFlags |= WHERE_COLUMN_IN;
-        if( ExprHasProperty(pExpr, EP_xIsSelect) ){
-          /* "x IN (SELECT ...)":  Assume the SELECT returns 25 rows */
-          nInMul *= 25;
-          bInEst = 1;
-        }else if( ALWAYS(pExpr->x.pList && pExpr->x.pList->nExpr) ){
-          /* "x IN (value, value, ...)" */
-          nInMul *= pExpr->x.pList->nExpr;
-        }
-      }else if( pTerm->eOperator & WO_ISNULL ){
-        wsFlags |= WHERE_COLUMN_NULL;
-      }
-#ifdef SQLITE_ENABLE_STAT3
-      if( nEq==0 && pProbe->aSample ) pFirstTerm = pTerm;
-#endif
-      used |= pTerm->prereqRight;
-    }
- 
-    /* If the index being considered is UNIQUE, and there is an equality 
-    ** constraint for all columns in the index, then this search will find
-    ** at most a single row. In this case set the WHERE_UNIQUE flag to 
-    ** indicate this to the caller.
-    **
-    ** Otherwise, if the search may find more than one row, test to see if
-    ** there is a range constraint on indexed column (nEq+1) that can be 
-    ** optimized using the index. 
-    */
-    if( nEq==pProbe->nColumn && pProbe->onError!=OE_None ){
-      testcase( wsFlags & WHERE_COLUMN_IN );
-      testcase( wsFlags & WHERE_COLUMN_NULL );
-      if( (wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_NULL))==0 ){
-        wsFlags |= WHERE_UNIQUE;
-      }
-    }else if( pProbe->bUnordered==0 ){
-      int j = (nEq==pProbe->nColumn ? -1 : pProbe->aiColumn[nEq]);
-      if( findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE|WO_GT|WO_GE, pIdx) ){
-        WhereTerm *pTop = findTerm(pWC, iCur, j, notReady, WO_LT|WO_LE, pIdx);
-        WhereTerm *pBtm = findTerm(pWC, iCur, j, notReady, WO_GT|WO_GE, pIdx);
-        whereRangeScanEst(pParse, pProbe, nEq, pBtm, pTop, &rangeDiv);
-        if( pTop ){
-          nBound = 1;
-          wsFlags |= WHERE_TOP_LIMIT;
-          used |= pTop->prereqRight;
-          testcase( pTop->pWC!=pWC );
-        }
-        if( pBtm ){
-          nBound++;
-          wsFlags |= WHERE_BTM_LIMIT;
-          used |= pBtm->prereqRight;
-          testcase( pBtm->pWC!=pWC );
-        }
-        wsFlags |= (WHERE_COLUMN_RANGE|WHERE_ROWID_RANGE);
-      }
-    }
-
-    /* If there is an ORDER BY clause and the index being considered will
-    ** naturally scan rows in the required order, set the appropriate flags
-    ** in wsFlags. Otherwise, if there is an ORDER BY clause but the index
-    ** will scan rows in a different order, set the bSort variable.  */
-    if( isSortingIndex(
-          pParse, pWC->pMaskSet, pProbe, iCur, pOrderBy, nEq, wsFlags, &rev)
-    ){
-      bSort = 0;
-      wsFlags |= WHERE_ROWID_RANGE|WHERE_COLUMN_RANGE|WHERE_ORDERBY;
-      wsFlags |= (rev ? WHERE_REVERSE : 0);
-    }
-
-    /* If there is a DISTINCT qualifier and this index will scan rows in
-    ** order of the DISTINCT expressions, clear bDist and set the appropriate
-    ** flags in wsFlags. */
-    if( isDistinctIndex(pParse, pWC, pProbe, iCur, pDistinct, nEq)
-     && (wsFlags & WHERE_COLUMN_IN)==0
-    ){
-      bDist = 0;
-      wsFlags |= WHERE_ROWID_RANGE|WHERE_COLUMN_RANGE|WHERE_DISTINCT;
-    }
-
-    /* If currently calculating the cost of using an index (not the IPK
-    ** index), determine if all required column data may be obtained without 
-    ** using the main table (i.e. if the index is a covering
-    ** index for this query). If it is, set the WHERE_IDX_ONLY flag in
-    ** wsFlags. Otherwise, set the bLookup variable to true.  */
-    if( pIdx && wsFlags ){
-      Bitmask m = pSrc->colUsed;
-      int j;
-      for(j=0; j<pIdx->nColumn; j++){
-        int x = pIdx->aiColumn[j];
-        if( x<BMS-1 ){
-          m &= ~(((Bitmask)1)<<x);
-        }
-      }
-      if( m==0 ){
-        wsFlags |= WHERE_IDX_ONLY;
-      }else{
-        bLookup = 1;
-      }
-    }
-
-    /*
-    ** Estimate the number of rows of output.  For an "x IN (SELECT...)"
-    ** constraint, do not let the estimate exceed half the rows in the table.
-    */
-    nRow = (double)(aiRowEst[nEq] * nInMul);
-    if( bInEst && nRow*2>aiRowEst[0] ){
-      nRow = aiRowEst[0]/2;
-      nInMul = (int)(nRow / aiRowEst[nEq]);
-    }
-
-#ifdef SQLITE_ENABLE_STAT3
-    /* If the constraint is of the form x=VALUE or x IN (E1,E2,...)
-    ** and we do not think that values of x are unique and if histogram
-    ** data is available for column x, then it might be possible
-    ** to get a better estimate on the number of rows based on
-    ** VALUE and how common that value is according to the histogram.
-    */
-    if( nRow>(double)1 && nEq==1 && pFirstTerm!=0 && aiRowEst[1]>1 ){
-      assert( (pFirstTerm->eOperator & (WO_EQ|WO_ISNULL|WO_IN))!=0 );
-      if( pFirstTerm->eOperator & (WO_EQ|WO_ISNULL) ){
-        testcase( pFirstTerm->eOperator==WO_EQ );
-        testcase( pFirstTerm->eOperator==WO_ISNULL );
-        whereEqualScanEst(pParse, pProbe, pFirstTerm->pExpr->pRight, &nRow);
-      }else if( bInEst==0 ){
-        assert( pFirstTerm->eOperator==WO_IN );
-        whereInScanEst(pParse, pProbe, pFirstTerm->pExpr->x.pList, &nRow);
-      }
-    }
-#endif /* SQLITE_ENABLE_STAT3 */
-
-    /* Adjust the number of output rows and downward to reflect rows
-    ** that are excluded by range constraints.
-    */
-    nRow = nRow/rangeDiv;
-    if( nRow<1 ) nRow = 1;
-
-    /* Experiments run on real SQLite databases show that the time needed
-    ** to do a binary search to locate a row in a table or index is roughly
-    ** log10(N) times the time to move from one row to the next row within
-    ** a table or index.  The actual times can vary, with the size of
-    ** records being an important factor.  Both moves and searches are
-    ** slower with larger records, presumably because fewer records fit
-    ** on one page and hence more pages have to be fetched.
-    **
-    ** The ANALYZE command and the sqlite_stat1 and sqlite_stat3 tables do
-    ** not give us data on the relative sizes of table and index records.
-    ** So this computation assumes table records are about twice as big
-    ** as index records
-    */
-    if( (wsFlags & WHERE_NOT_FULLSCAN)==0 ){
-      /* The cost of a full table scan is a number of move operations equal
-      ** to the number of rows in the table.
-      **
-      ** We add an additional 4x penalty to full table scans.  This causes
-      ** the cost function to err on the side of choosing an index over
-      ** choosing a full scan.  This 4x full-scan penalty is an arguable
-      ** decision and one which we expect to revisit in the future.  But
-      ** it seems to be working well enough at the moment.
-      */
-      cost = aiRowEst[0]*4;
-    }else{
-      log10N = estLog(aiRowEst[0]);
-      cost = nRow;
-      if( pIdx ){
-        if( bLookup ){
-          /* For an index lookup followed by a table lookup:
-          **    nInMul index searches to find the start of each index range
-          **  + nRow steps through the index
-          **  + nRow table searches to lookup the table entry using the rowid
-          */
-          cost += (nInMul + nRow)*log10N;
-        }else{
-          /* For a covering index:
-          **     nInMul index searches to find the initial entry 
-          **   + nRow steps through the index
-          */
-          cost += nInMul*log10N;
-        }
-      }else{
-        /* For a rowid primary key lookup:
-        **    nInMult table searches to find the initial entry for each range
-        **  + nRow steps through the table
-        */
-        cost += nInMul*log10N;
-      }
-    }
-
-    /* Add in the estimated cost of sorting the result.  Actual experimental
-    ** measurements of sorting performance in SQLite show that sorting time
-    ** adds C*N*log10(N) to the cost, where N is the number of rows to be 
-    ** sorted and C is a factor between 1.95 and 4.3.  We will split the
-    ** difference and select C of 3.0.
-    */
-    if( bSort ){
-      cost += nRow*estLog(nRow)*3;
-    }
-    if( bDist ){
-      cost += nRow*estLog(nRow)*3;
-    }
-
-    /**** Cost of using this index has now been computed ****/
-
-    /* If there are additional constraints on this table that cannot
-    ** be used with the current index, but which might lower the number
-    ** of output rows, adjust the nRow value accordingly.  This only 
-    ** matters if the current index is the least costly, so do not bother
-    ** with this step if we already know this index will not be chosen.
-    ** Also, never reduce the output row count below 2 using this step.
-    **
-    ** It is critical that the notValid mask be used here instead of
-    ** the notReady mask.  When computing an "optimal" index, the notReady
-    ** mask will only have one bit set - the bit for the current table.
-    ** The notValid mask, on the other hand, always has all bits set for
-    ** tables that are not in outer loops.  If notReady is used here instead
-    ** of notValid, then a optimal index that depends on inner joins loops
-    ** might be selected even when there exists an optimal index that has
-    ** no such dependency.
-    */
-    if( nRow>2 && cost<=pCost->rCost ){
-      int k;                       /* Loop counter */
-      int nSkipEq = nEq;           /* Number of == constraints to skip */
-      int nSkipRange = nBound;     /* Number of < constraints to skip */
-      Bitmask thisTab;             /* Bitmap for pSrc */
-
-      thisTab = getMask(pWC->pMaskSet, iCur);
-      for(pTerm=pWC->a, k=pWC->nTerm; nRow>2 && k; k--, pTerm++){
-        if( pTerm->wtFlags & TERM_VIRTUAL ) continue;
-        if( (pTerm->prereqAll & notValid)!=thisTab ) continue;
-        if( pTerm->eOperator & (WO_EQ|WO_IN|WO_ISNULL) ){
-          if( nSkipEq ){
-            /* Ignore the first nEq equality matches since the index
-            ** has already accounted for these */
-            nSkipEq--;
-          }else{
-            /* Assume each additional equality match reduces the result
-            ** set size by a factor of 10 */
-            nRow /= 10;
-          }
-        }else if( pTerm->eOperator & (WO_LT|WO_LE|WO_GT|WO_GE) ){
-          if( nSkipRange ){
-            /* Ignore the first nSkipRange range constraints since the index
-            ** has already accounted for these */
-            nSkipRange--;
-          }else{
-            /* Assume each additional range constraint reduces the result
-            ** set size by a factor of 3.  Indexed range constraints reduce
-            ** the search space by a larger factor: 4.  We make indexed range
-            ** more selective intentionally because of the subjective 
-            ** observation that indexed range constraints really are more
-            ** selective in practice, on average. */
-            nRow /= 3;
-          }
-        }else if( pTerm->eOperator!=WO_NOOP ){
-          /* Any other expression lowers the output row count by half */
-          nRow /= 2;
-        }
-      }
-      if( nRow<2 ) nRow = 2;
-    }
-
-
-    WHERETRACE((
-      "%s(%s): nEq=%d nInMul=%d rangeDiv=%d bSort=%d bLookup=%d wsFlags=0x%x\n"
-      "         notReady=0x%llx log10N=%.1f nRow=%.1f cost=%.1f used=0x%llx\n",
-      pSrc->pTab->zName, (pIdx ? pIdx->zName : "ipk"), 
-      nEq, nInMul, (int)rangeDiv, bSort, bLookup, wsFlags,
-      notReady, log10N, nRow, cost, used
-    ));
-
-    /* If this index is the best we have seen so far, then record this
-    ** index and its cost in the pCost structure.
-    */
-    if( (!pIdx || wsFlags)
-     && (cost<pCost->rCost || (cost<=pCost->rCost && nRow<pCost->plan.nRow))
-    ){
-      pCost->rCost = cost;
-      pCost->used = used;
-      pCost->plan.nRow = nRow;
-      pCost->plan.wsFlags = (wsFlags&wsFlagMask);
-      pCost->plan.nEq = nEq;
-      pCost->plan.u.pIdx = pIdx;
-    }
-
-    /* If there was an INDEXED BY clause, then only that one index is
-    ** considered. */
-    if( pSrc->pIndex ) break;
-
-    /* Reset masks for the next index in the loop */
-    wsFlagMask = ~(WHERE_ROWID_EQ|WHERE_ROWID_RANGE);
-    eqTermMask = idxEqTermMask;
-  }
-
-  /* If there is no ORDER BY clause and the SQLITE_ReverseOrder flag
-  ** is set, then reverse the order that the index will be scanned
-  ** in. This is used for application testing, to help find cases
-  ** where application behaviour depends on the (undefined) order that
-  ** SQLite outputs rows in in the absence of an ORDER BY clause.  */
-  if( !pOrderBy && pParse->db->flags & SQLITE_ReverseOrder ){
-    pCost->plan.wsFlags |= WHERE_REVERSE;
-  }
-
-  assert( pOrderBy || (pCost->plan.wsFlags&WHERE_ORDERBY)==0 );
-  assert( pCost->plan.u.pIdx==0 || (pCost->plan.wsFlags&WHERE_ROWID_EQ)==0 );
-  assert( pSrc->pIndex==0 
-       || pCost->plan.u.pIdx==0 
-       || pCost->plan.u.pIdx==pSrc->pIndex 
-  );
-
-  WHERETRACE(("best index is: %s\n", 
-    ((pCost->plan.wsFlags & WHERE_NOT_FULLSCAN)==0 ? "none" : 
-         pCost->plan.u.pIdx ? pCost->plan.u.pIdx->zName : "ipk")
-  ));
-  
-  bestOrClauseIndex(pParse, pWC, pSrc, notReady, notValid, pOrderBy, pCost);
-  bestAutomaticIndex(pParse, pWC, pSrc, notReady, pCost);
-  pCost->plan.wsFlags |= eqTermMask;
-}
-
-/*
-** Find the query plan for accessing table pSrc->pTab. Write the
-** best query plan and its cost into the WhereCost object supplied 
-** as the last parameter. This function may calculate the cost of
-** both real and virtual table scans.
-*/
-static void bestIndex(
-  Parse *pParse,              /* The parsing context */
-  WhereClause *pWC,           /* The WHERE clause */
-  struct SrcList_item *pSrc,  /* The FROM clause term to search */
-  Bitmask notReady,           /* Mask of cursors not available for indexing */
-  Bitmask notValid,           /* Cursors not available for any purpose */
-  ExprList *pOrderBy,         /* The ORDER BY clause */
-  WhereCost *pCost            /* Lowest cost query plan */
-){
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-  if( IsVirtual(pSrc->pTab) ){
-    sqlite3_index_info *p = 0;
-    bestVirtualIndex(pParse, pWC, pSrc, notReady, notValid, pOrderBy, pCost,&p);
-    if( p->needToFreeIdxStr ){
-      sqlite3_free(p->idxStr);
-    }
-    sqlite3DbFree(pParse->db, p);
-  }else
-#endif
-  {
-    bestBtreeIndex(pParse, pWC, pSrc, notReady, notValid, pOrderBy, 0, pCost);
-  }
-}
-
 /*
 ** Disable a term in the WHERE clause.  Except, do not disable the term
 ** if it controls a LEFT OUTER JOIN and it did not originate in the ON
@@ -107072,9 +107568,6 @@ static void bestIndex(
 ** in the ON clause.  The term is disabled in (3) because it is not part
 ** of a LEFT OUTER JOIN.  In (1), the term is not disabled.
 **
-** IMPLEMENTATION-OF: R-24597-58655 No tests are done for terms that are
-** completely satisfied by indices.
-**
 ** Disabling a term causes that term to not be tested in the inner loop
 ** of the join.  Disabling is an optimization.  When terms are satisfied
 ** by indices, we disable them to prevent redundant tests in the inner
@@ -107152,7 +107645,9 @@ static void codeApplyAffinity(Parse *pParse, int base, int n, char *zAff){
 static int codeEqualityTerm(
   Parse *pParse,      /* The parsing context */
   WhereTerm *pTerm,   /* The term of the WHERE clause to be coded */
-  WhereLevel *pLevel, /* When level of the FROM clause we are working on */
+  WhereLevel *pLevel, /* The level of the FROM clause we are working on */
+  int iEq,            /* Index of the equality term within this level */
+  int bRev,           /* True for reverse-order IN operations */
   int iTarget         /* Attempt to leave results in this register */
 ){
   Expr *pX = pTerm->pExpr;
@@ -107170,13 +107665,27 @@ static int codeEqualityTerm(
     int eType;
     int iTab;
     struct InLoop *pIn;
+    WhereLoop *pLoop = pLevel->pWLoop;
 
+    if( (pLoop->wsFlags & WHERE_VIRTUALTABLE)==0
+      && pLoop->u.btree.pIndex!=0
+      && pLoop->u.btree.pIndex->aSortOrder[iEq]
+    ){
+      testcase( iEq==0 );
+      testcase( bRev );
+      bRev = !bRev;
+    }
     assert( pX->op==TK_IN );
     iReg = iTarget;
     eType = sqlite3FindInIndex(pParse, pX, 0);
+    if( eType==IN_INDEX_INDEX_DESC ){
+      testcase( bRev );
+      bRev = !bRev;
+    }
     iTab = pX->iTable;
-    sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
-    assert( pLevel->plan.wsFlags & WHERE_IN_ABLE );
+    sqlite3VdbeAddOp2(v, bRev ? OP_Last : OP_Rewind, iTab, 0);
+    assert( (pLoop->wsFlags & WHERE_MULTI_OR)==0 );
+    pLoop->wsFlags |= WHERE_IN_ABLE;
     if( pLevel->u.in.nIn==0 ){
       pLevel->addrNxt = sqlite3VdbeMakeLabel(v);
     }
@@ -107193,6 +107702,7 @@ static int codeEqualityTerm(
       }else{
         pIn->addrInTop = sqlite3VdbeAddOp3(v, OP_Column, iTab, 0, iReg);
       }
+      pIn->eEndLoopOp = bRev ? OP_Prev : OP_Next;
       sqlite3VdbeAddOp1(v, OP_IsNull, iReg);
     }else{
       pLevel->u.in.nIn = 0;
@@ -107245,29 +107755,31 @@ static int codeEqualityTerm(
 static int codeAllEqualityTerms(
   Parse *pParse,        /* Parsing context */
   WhereLevel *pLevel,   /* Which nested loop of the FROM we are coding */
-  WhereClause *pWC,     /* The WHERE clause */
-  Bitmask notReady,     /* Which parts of FROM have not yet been coded */
+  int bRev,             /* Reverse the order of IN operators */
   int nExtraReg,        /* Number of extra registers to allocate */
   char **pzAff          /* OUT: Set to point to affinity string */
 ){
-  int nEq = pLevel->plan.nEq;   /* The number of == or IN constraints to code */
+  int nEq;                      /* The number of == or IN constraints to code */
   Vdbe *v = pParse->pVdbe;      /* The vm under construction */
   Index *pIdx;                  /* The index being used for this loop */
-  int iCur = pLevel->iTabCur;   /* The cursor of the table */
   WhereTerm *pTerm;             /* A single constraint term */
+  WhereLoop *pLoop;             /* The WhereLoop object */
   int j;                        /* Loop counter */
   int regBase;                  /* Base register */
   int nReg;                     /* Number of registers to allocate */
   char *zAff;                   /* Affinity string to return */
 
   /* This module is only called on query plans that use an index. */
-  assert( pLevel->plan.wsFlags & WHERE_INDEXED );
-  pIdx = pLevel->plan.u.pIdx;
+  pLoop = pLevel->pWLoop;
+  assert( (pLoop->wsFlags & WHERE_VIRTUALTABLE)==0 );
+  nEq = pLoop->u.btree.nEq;
+  pIdx = pLoop->u.btree.pIndex;
+  assert( pIdx!=0 );
 
   /* Figure out how many memory cells we will need then allocate them.
   */
   regBase = pParse->nMem + 1;
-  nReg = pLevel->plan.nEq + nExtraReg;
+  nReg = pLoop->u.btree.nEq + nExtraReg;
   pParse->nMem += nReg;
 
   zAff = sqlite3DbStrDup(pParse->db, sqlite3IndexAffinityStr(v, pIdx));
@@ -107277,17 +107789,16 @@ static int codeAllEqualityTerms(
 
   /* Evaluate the equality constraints
   */
-  assert( pIdx->nColumn>=nEq );
+  assert( zAff==0 || strlen(zAff)>=nEq );
   for(j=0; j<nEq; j++){
     int r1;
-    int k = pIdx->aiColumn[j];
-    pTerm = findTerm(pWC, iCur, k, notReady, pLevel->plan.wsFlags, pIdx);
-    if( NEVER(pTerm==0) ) break;
+    pTerm = pLoop->aLTerm[j];
+    assert( pTerm!=0 );
     /* The following true for indices with redundant columns. 
     ** Ex: CREATE INDEX i1 ON t1(a,b,a); SELECT * FROM t1 WHERE a=0 AND b=0; */
     testcase( (pTerm->wtFlags & TERM_CODED)!=0 );
-    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
-    r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
+    testcase( pTerm->wtFlags & TERM_VIRTUAL );
+    r1 = codeEqualityTerm(pParse, pTerm, pLevel, j, bRev, regBase+j);
     if( r1!=regBase+j ){
       if( nReg==1 ){
         sqlite3ReleaseTempReg(pParse, regBase);
@@ -107355,31 +107866,31 @@ static void explainAppendTerm(
 ** It is the responsibility of the caller to free the buffer when it is
 ** no longer required.
 */
-static char *explainIndexRange(sqlite3 *db, WhereLevel *pLevel, Table *pTab){
-  WherePlan *pPlan = &pLevel->plan;
-  Index *pIndex = pPlan->u.pIdx;
-  int nEq = pPlan->nEq;
+static char *explainIndexRange(sqlite3 *db, WhereLoop *pLoop, Table *pTab){
+  Index *pIndex = pLoop->u.btree.pIndex;
+  int nEq = pLoop->u.btree.nEq;
   int i, j;
   Column *aCol = pTab->aCol;
   int *aiColumn = pIndex->aiColumn;
   StrAccum txt;
 
-  if( nEq==0 && (pPlan->wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))==0 ){
+  if( nEq==0 && (pLoop->wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))==0 ){
     return 0;
   }
   sqlite3StrAccumInit(&txt, 0, 0, SQLITE_MAX_LENGTH);
   txt.db = db;
   sqlite3StrAccumAppend(&txt, " (", 2);
   for(i=0; i<nEq; i++){
-    explainAppendTerm(&txt, i, aCol[aiColumn[i]].zName, "=");
+    char *z = (i==pIndex->nColumn ) ? "rowid" : aCol[aiColumn[i]].zName;
+    explainAppendTerm(&txt, i, z, "=");
   }
 
   j = i;
-  if( pPlan->wsFlags&WHERE_BTM_LIMIT ){
+  if( pLoop->wsFlags&WHERE_BTM_LIMIT ){
     char *z = (j==pIndex->nColumn ) ? "rowid" : aCol[aiColumn[j]].zName;
     explainAppendTerm(&txt, i++, z, ">");
   }
-  if( pPlan->wsFlags&WHERE_TOP_LIMIT ){
+  if( pLoop->wsFlags&WHERE_TOP_LIMIT ){
     char *z = (j==pIndex->nColumn ) ? "rowid" : aCol[aiColumn[j]].zName;
     explainAppendTerm(&txt, i, z, "<");
   }
@@ -107402,20 +107913,22 @@ static void explainOneScan(
   u16 wctrlFlags                  /* Flags passed to sqlite3WhereBegin() */
 ){
   if( pParse->explain==2 ){
-    u32 flags = pLevel->plan.wsFlags;
     struct SrcList_item *pItem = &pTabList->a[pLevel->iFrom];
     Vdbe *v = pParse->pVdbe;      /* VM being constructed */
     sqlite3 *db = pParse->db;     /* Database handle */
     char *zMsg;                   /* Text to add to EQP output */
-    sqlite3_int64 nRow;           /* Expected number of rows visited by scan */
     int iId = pParse->iSelectId;  /* Select id (left-most output column) */
     int isSearch;                 /* True for a SEARCH. False for SCAN. */
+    WhereLoop *pLoop;             /* The controlling WhereLoop object */
+    u32 flags;                    /* Flags that describe this loop */
 
+    pLoop = pLevel->pWLoop;
+    flags = pLoop->wsFlags;
     if( (flags&WHERE_MULTI_OR) || (wctrlFlags&WHERE_ONETABLE_ONLY) ) return;
 
-    isSearch = (pLevel->plan.nEq>0)
-             || (flags&(WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0
-             || (wctrlFlags&(WHERE_ORDERBY_MIN|WHERE_ORDERBY_MAX));
+    isSearch = (flags&(WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0
+            || ((flags&WHERE_VIRTUALTABLE)==0 && (pLoop->u.btree.nEq>0))
+            || (wctrlFlags&(WHERE_ORDERBY_MIN|WHERE_ORDERBY_MAX));
 
     zMsg = sqlite3MPrintf(db, "%s", isSearch?"SEARCH":"SCAN");
     if( pItem->pSelect ){
@@ -107427,43 +107940,37 @@ static void explainOneScan(
     if( pItem->zAlias ){
       zMsg = sqlite3MAppendf(db, zMsg, "%s AS %s", zMsg, pItem->zAlias);
     }
-    if( (flags & WHERE_INDEXED)!=0 ){
-      char *zWhere = explainIndexRange(db, pLevel, pItem->pTab);
-      zMsg = sqlite3MAppendf(db, zMsg, "%s USING %s%sINDEX%s%s%s", zMsg, 
-          ((flags & WHERE_TEMP_INDEX)?"AUTOMATIC ":""),
-          ((flags & WHERE_IDX_ONLY)?"COVERING ":""),
-          ((flags & WHERE_TEMP_INDEX)?"":" "),
-          ((flags & WHERE_TEMP_INDEX)?"": pLevel->plan.u.pIdx->zName),
-          zWhere
-      );
+    if( (flags & (WHERE_IPK|WHERE_VIRTUALTABLE))==0
+     && ALWAYS(pLoop->u.btree.pIndex!=0)
+    ){
+      char *zWhere = explainIndexRange(db, pLoop, pItem->pTab);
+      zMsg = sqlite3MAppendf(db, zMsg,
+               ((flags & WHERE_AUTO_INDEX) ? 
+                   "%s USING AUTOMATIC %sINDEX%.0s%s" :
+                   "%s USING %sINDEX %s%s"), 
+               zMsg, ((flags & WHERE_IDX_ONLY) ? "COVERING " : ""),
+               pLoop->u.btree.pIndex->zName, zWhere);
       sqlite3DbFree(db, zWhere);
-    }else if( flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
+    }else if( (flags & WHERE_IPK)!=0 && (flags & WHERE_CONSTRAINT)!=0 ){
       zMsg = sqlite3MAppendf(db, zMsg, "%s USING INTEGER PRIMARY KEY", zMsg);
 
-      if( flags&WHERE_ROWID_EQ ){
+      if( flags&(WHERE_COLUMN_EQ|WHERE_COLUMN_IN) ){
         zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid=?)", zMsg);
       }else if( (flags&WHERE_BOTH_LIMIT)==WHERE_BOTH_LIMIT ){
         zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid>? AND rowid<?)", zMsg);
       }else if( flags&WHERE_BTM_LIMIT ){
         zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid>?)", zMsg);
-      }else if( flags&WHERE_TOP_LIMIT ){
+      }else if( ALWAYS(flags&WHERE_TOP_LIMIT) ){
         zMsg = sqlite3MAppendf(db, zMsg, "%s (rowid<?)", zMsg);
       }
     }
 #ifndef SQLITE_OMIT_VIRTUALTABLE
     else if( (flags & WHERE_VIRTUALTABLE)!=0 ){
-      sqlite3_index_info *pVtabIdx = pLevel->plan.u.pVtabIdx;
       zMsg = sqlite3MAppendf(db, zMsg, "%s VIRTUAL TABLE INDEX %d:%s", zMsg,
-                  pVtabIdx->idxNum, pVtabIdx->idxStr);
+                  pLoop->u.vtab.idxNum, pLoop->u.vtab.idxStr);
     }
 #endif
-    if( wctrlFlags&(WHERE_ORDERBY_MIN|WHERE_ORDERBY_MAX) ){
-      testcase( wctrlFlags & WHERE_ORDERBY_MIN );
-      nRow = 1;
-    }else{
-      nRow = (sqlite3_int64)pLevel->plan.nRow;
-    }
-    zMsg = sqlite3MAppendf(db, zMsg, "%s (~%lld rows)", zMsg, nRow);
+    zMsg = sqlite3MAppendf(db, zMsg, "%s", zMsg);
     sqlite3VdbeAddOp4(v, OP_Explain, iId, iLevel, iFrom, zMsg, P4_DYNAMIC);
   }
 }
@@ -107479,7 +107986,6 @@ static void explainOneScan(
 static Bitmask codeOneLoopStart(
   WhereInfo *pWInfo,   /* Complete information about the WHERE clause */
   int iLevel,          /* Which level of pWInfo->a[] should be coded */
-  u16 wctrlFlags,      /* One of the WHERE_* flags defined in sqliteInt.h */
   Bitmask notReady     /* Which tables are currently available */
 ){
   int j, k;            /* Loop counters */
@@ -107488,25 +107994,31 @@ static Bitmask codeOneLoopStart(
   int omitTable;       /* True if we use the index only */
   int bRev;            /* True if we need to scan in reverse order */
   WhereLevel *pLevel;  /* The where level to be coded */
+  WhereLoop *pLoop;    /* The WhereLoop object being coded */
   WhereClause *pWC;    /* Decomposition of the entire WHERE clause */
   WhereTerm *pTerm;               /* A WHERE clause term */
   Parse *pParse;                  /* Parsing context */
+  sqlite3 *db;                    /* Database connection */
   Vdbe *v;                        /* The prepared stmt under constructions */
   struct SrcList_item *pTabItem;  /* FROM clause term being coded */
   int addrBrk;                    /* Jump here to break out of the loop */
   int addrCont;                   /* Jump here to continue with next cycle */
   int iRowidReg = 0;        /* Rowid is stored in this register, if not zero */
   int iReleaseReg = 0;      /* Temp register to free before returning */
+  Bitmask newNotReady;      /* Return value */
 
   pParse = pWInfo->pParse;
   v = pParse->pVdbe;
-  pWC = pWInfo->pWC;
+  pWC = &pWInfo->sWC;
+  db = pParse->db;
   pLevel = &pWInfo->a[iLevel];
+  pLoop = pLevel->pWLoop;
   pTabItem = &pWInfo->pTabList->a[pLevel->iFrom];
   iCur = pTabItem->iCursor;
-  bRev = (pLevel->plan.wsFlags & WHERE_REVERSE)!=0;
-  omitTable = (pLevel->plan.wsFlags & WHERE_IDX_ONLY)!=0 
-           && (wctrlFlags & WHERE_FORCE_TABLE)==0;
+  bRev = (pWInfo->revMask>>iLevel)&1;
+  omitTable = (pLoop->wsFlags & WHERE_IDX_ONLY)!=0 
+           && (pWInfo->wctrlFlags & WHERE_FORCE_TABLE)==0;
+  VdbeNoopComment((v, "Begin Join Loop %d", iLevel));
 
   /* Create labels for the "break" and "continue" instructions
   ** for the current loop.  Jump to addrBrk to break out of a loop.
@@ -107531,40 +108043,48 @@ static Bitmask codeOneLoopStart(
     VdbeComment((v, "init LEFT JOIN no-match flag"));
   }
 
+  /* Special case of a FROM clause subquery implemented as a co-routine */
+  if( pTabItem->viaCoroutine ){
+    int regYield = pTabItem->regReturn;
+    sqlite3VdbeAddOp2(v, OP_Integer, pTabItem->addrFillSub-1, regYield);
+    pLevel->p2 =  sqlite3VdbeAddOp1(v, OP_Yield, regYield);
+    VdbeComment((v, "next row of co-routine %s", pTabItem->pTab->zName));
+    sqlite3VdbeAddOp2(v, OP_If, regYield+1, addrBrk);
+    pLevel->op = OP_Goto;
+  }else
+
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  if(  (pLevel->plan.wsFlags & WHERE_VIRTUALTABLE)!=0 ){
-    /* Case 0:  The table is a virtual-table.  Use the VFilter and VNext
+  if(  (pLoop->wsFlags & WHERE_VIRTUALTABLE)!=0 ){
+    /* Case 1:  The table is a virtual-table.  Use the VFilter and VNext
     **          to access the data.
     */
     int iReg;   /* P3 Value for OP_VFilter */
-    sqlite3_index_info *pVtabIdx = pLevel->plan.u.pVtabIdx;
-    int nConstraint = pVtabIdx->nConstraint;
-    struct sqlite3_index_constraint_usage *aUsage =
-                                                pVtabIdx->aConstraintUsage;
-    const struct sqlite3_index_constraint *aConstraint =
-                                                pVtabIdx->aConstraint;
+    int addrNotFound;
+    int nConstraint = pLoop->nLTerm;
 
     sqlite3ExprCachePush(pParse);
     iReg = sqlite3GetTempRange(pParse, nConstraint+2);
-    for(j=1; j<=nConstraint; j++){
-      for(k=0; k<nConstraint; k++){
-        if( aUsage[k].argvIndex==j ){
-          int iTerm = aConstraint[k].iTermOffset;
-          sqlite3ExprCode(pParse, pWC->a[iTerm].pExpr->pRight, iReg+j+1);
-          break;
-        }
-      }
-      if( k==nConstraint ) break;
-    }
-    sqlite3VdbeAddOp2(v, OP_Integer, pVtabIdx->idxNum, iReg);
-    sqlite3VdbeAddOp2(v, OP_Integer, j-1, iReg+1);
-    sqlite3VdbeAddOp4(v, OP_VFilter, iCur, addrBrk, iReg, pVtabIdx->idxStr,
-                      pVtabIdx->needToFreeIdxStr ? P4_MPRINTF : P4_STATIC);
-    pVtabIdx->needToFreeIdxStr = 0;
+    addrNotFound = pLevel->addrBrk;
     for(j=0; j<nConstraint; j++){
-      if( aUsage[j].omit ){
-        int iTerm = aConstraint[j].iTermOffset;
-        disableTerm(pLevel, &pWC->a[iTerm]);
+      int iTarget = iReg+j+2;
+      pTerm = pLoop->aLTerm[j];
+      if( pTerm==0 ) continue;
+      if( pTerm->eOperator & WO_IN ){
+        codeEqualityTerm(pParse, pTerm, pLevel, j, bRev, iTarget);
+        addrNotFound = pLevel->addrNxt;
+      }else{
+        sqlite3ExprCode(pParse, pTerm->pExpr->pRight, iTarget);
+      }
+    }
+    sqlite3VdbeAddOp2(v, OP_Integer, pLoop->u.vtab.idxNum, iReg);
+    sqlite3VdbeAddOp2(v, OP_Integer, nConstraint, iReg+1);
+    sqlite3VdbeAddOp4(v, OP_VFilter, iCur, addrNotFound, iReg,
+                      pLoop->u.vtab.idxStr,
+                      pLoop->u.vtab.needFree ? P4_MPRINTF : P4_STATIC);
+    pLoop->u.vtab.needFree = 0;
+    for(j=0; j<nConstraint && j<16; j++){
+      if( (pLoop->u.vtab.omitMask>>j)&1 ){
+        disableTerm(pLevel, pLoop->aLTerm[j]);
       }
     }
     pLevel->op = OP_VNext;
@@ -107575,28 +108095,33 @@ static Bitmask codeOneLoopStart(
   }else
 #endif /* SQLITE_OMIT_VIRTUALTABLE */
 
-  if( pLevel->plan.wsFlags & WHERE_ROWID_EQ ){
-    /* Case 1:  We can directly reference a single row using an
+  if( (pLoop->wsFlags & WHERE_IPK)!=0
+   && (pLoop->wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_EQ))!=0
+  ){
+    /* Case 2:  We can directly reference a single row using an
     **          equality comparison against the ROWID field.  Or
     **          we reference multiple rows using a "rowid IN (...)"
     **          construct.
     */
+    assert( pLoop->u.btree.nEq==1 );
     iReleaseReg = sqlite3GetTempReg(pParse);
-    pTerm = findTerm(pWC, iCur, -1, notReady, WO_EQ|WO_IN, 0);
+    pTerm = pLoop->aLTerm[0];
     assert( pTerm!=0 );
     assert( pTerm->pExpr!=0 );
-    assert( pTerm->leftCursor==iCur );
     assert( omitTable==0 );
-    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
-    iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, iReleaseReg);
+    testcase( pTerm->wtFlags & TERM_VIRTUAL );
+    iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, 0, bRev, iReleaseReg);
     addrNxt = pLevel->addrNxt;
     sqlite3VdbeAddOp2(v, OP_MustBeInt, iRowidReg, addrNxt);
     sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addrNxt, iRowidReg);
+    sqlite3ExprCacheAffinityChange(pParse, iRowidReg, 1);
     sqlite3ExprCacheStore(pParse, iCur, -1, iRowidReg);
     VdbeComment((v, "pk"));
     pLevel->op = OP_Noop;
-  }else if( pLevel->plan.wsFlags & WHERE_ROWID_RANGE ){
-    /* Case 2:  We have an inequality comparison against the ROWID field.
+  }else if( (pLoop->wsFlags & WHERE_IPK)!=0
+         && (pLoop->wsFlags & WHERE_COLUMN_RANGE)!=0
+  ){
+    /* Case 3:  We have an inequality comparison against the ROWID field.
     */
     int testOp = OP_Noop;
     int start;
@@ -107604,8 +108129,11 @@ static Bitmask codeOneLoopStart(
     WhereTerm *pStart, *pEnd;
 
     assert( omitTable==0 );
-    pStart = findTerm(pWC, iCur, -1, notReady, WO_GT|WO_GE, 0);
-    pEnd = findTerm(pWC, iCur, -1, notReady, WO_LT|WO_LE, 0);
+    j = 0;
+    pStart = pEnd = 0;
+    if( pLoop->wsFlags & WHERE_BTM_LIMIT ) pStart = pLoop->aLTerm[j++];
+    if( pLoop->wsFlags & WHERE_TOP_LIMIT ) pEnd = pLoop->aLTerm[j++];
+    assert( pStart!=0 || pEnd!=0 );
     if( bRev ){
       pTerm = pStart;
       pStart = pEnd;
@@ -107628,10 +108156,11 @@ static Bitmask codeOneLoopStart(
       assert( TK_LT==TK_GT+2 );      /*  ... of the TK_xx values... */
       assert( TK_GE==TK_GT+3 );      /*  ... is correcct. */
 
-      testcase( pStart->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
+      assert( (pStart->wtFlags & TERM_VNULL)==0 );
+      testcase( pStart->wtFlags & TERM_VIRTUAL );
       pX = pStart->pExpr;
       assert( pX!=0 );
-      assert( pStart->leftCursor==iCur );
+      testcase( pStart->leftCursor!=iCur ); /* transitive constraints */
       r1 = sqlite3ExprCodeTemp(pParse, pX->pRight, &rTemp);
       sqlite3VdbeAddOp3(v, aMoveOp[pX->op-TK_GT], iCur, addrBrk, r1);
       VdbeComment((v, "pk"));
@@ -107645,8 +108174,9 @@ static Bitmask codeOneLoopStart(
       Expr *pX;
       pX = pEnd->pExpr;
       assert( pX!=0 );
-      assert( pEnd->leftCursor==iCur );
-      testcase( pEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
+      assert( (pEnd->wtFlags & TERM_VNULL)==0 );
+      testcase( pEnd->leftCursor!=iCur ); /* Transitive constraints */
+      testcase( pEnd->wtFlags & TERM_VIRTUAL );
       memEndValue = ++pParse->nMem;
       sqlite3ExprCode(pParse, pX->pRight, memEndValue);
       if( pX->op==TK_LT || pX->op==TK_GT ){
@@ -107660,11 +108190,7 @@ static Bitmask codeOneLoopStart(
     pLevel->op = bRev ? OP_Prev : OP_Next;
     pLevel->p1 = iCur;
     pLevel->p2 = start;
-    if( pStart==0 && pEnd==0 ){
-      pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP;
-    }else{
-      assert( pLevel->p5==0 );
-    }
+    assert( pLevel->p5==0 );
     if( testOp!=OP_Noop ){
       iRowidReg = iReleaseReg = sqlite3GetTempReg(pParse);
       sqlite3VdbeAddOp2(v, OP_Rowid, iCur, iRowidReg);
@@ -107672,8 +108198,8 @@ static Bitmask codeOneLoopStart(
       sqlite3VdbeAddOp3(v, testOp, memEndValue, addrBrk, iRowidReg);
       sqlite3VdbeChangeP5(v, SQLITE_AFF_NUMERIC | SQLITE_JUMPIFNULL);
     }
-  }else if( pLevel->plan.wsFlags & (WHERE_COLUMN_RANGE|WHERE_COLUMN_EQ) ){
-    /* Case 3: A scan using an index.
+  }else if( pLoop->wsFlags & WHERE_INDEXED ){
+    /* Case 4: A scan using an index.
     **
     **         The WHERE clause may contain zero or more equality 
     **         terms ("==" or "IN" operators) that refer to the N
@@ -107719,8 +108245,8 @@ static Bitmask codeOneLoopStart(
       OP_IdxGE,            /* 1: (end_constraints && !bRev) */
       OP_IdxLT             /* 2: (end_constraints && bRev) */
     };
-    int nEq = pLevel->plan.nEq;  /* Number of == or IN terms */
-    int isMinQuery = 0;          /* If this is an optimized SELECT min(x).. */
+    int nEq = pLoop->u.btree.nEq;  /* Number of == or IN terms */
+    int isMinQuery = 0;            /* If this is an optimized SELECT min(x).. */
     int regBase;                 /* Base register holding constraint values */
     int r1;                      /* Temp register */
     WhereTerm *pRangeStart = 0;  /* Inequality constraint at range start */
@@ -107736,9 +108262,8 @@ static Bitmask codeOneLoopStart(
     char *zStartAff;             /* Affinity for start of range constraint */
     char *zEndAff;               /* Affinity for end of range constraint */
 
-    pIdx = pLevel->plan.u.pIdx;
+    pIdx = pLoop->u.btree.pIndex;
     iIdxCur = pLevel->iIdxCur;
-    k = (nEq==pIdx->nColumn ? -1 : pIdx->aiColumn[nEq]);
 
     /* If this loop satisfies a sort order (pOrderBy) request that 
     ** was passed to this function to implement a "SELECT min(x) ..." 
@@ -107748,8 +108273,8 @@ static Bitmask codeOneLoopStart(
     ** the first one after the nEq equality constraints in the index,
     ** this requires some special handling.
     */
-    if( (wctrlFlags&WHERE_ORDERBY_MIN)!=0
-     && (pLevel->plan.wsFlags&WHERE_ORDERBY)
+    if( (pWInfo->wctrlFlags&WHERE_ORDERBY_MIN)!=0
+     && (pWInfo->bOBSat!=0)
      && (pIdx->nColumn>nEq)
     ){
       /* assert( pOrderBy->nExpr==1 ); */
@@ -107761,12 +108286,13 @@ static Bitmask codeOneLoopStart(
     /* Find any inequality constraint terms for the start and end 
     ** of the range. 
     */
-    if( pLevel->plan.wsFlags & WHERE_TOP_LIMIT ){
-      pRangeEnd = findTerm(pWC, iCur, k, notReady, (WO_LT|WO_LE), pIdx);
+    j = nEq;
+    if( pLoop->wsFlags & WHERE_BTM_LIMIT ){
+      pRangeStart = pLoop->aLTerm[j++];
       nExtraReg = 1;
     }
-    if( pLevel->plan.wsFlags & WHERE_BTM_LIMIT ){
-      pRangeStart = findTerm(pWC, iCur, k, notReady, (WO_GT|WO_GE), pIdx);
+    if( pLoop->wsFlags & WHERE_TOP_LIMIT ){
+      pRangeEnd = pLoop->aLTerm[j++];
       nExtraReg = 1;
     }
 
@@ -107774,10 +108300,8 @@ static Bitmask codeOneLoopStart(
     ** and store the values of those terms in an array of registers
     ** starting at regBase.
     */
-    regBase = codeAllEqualityTerms(
-        pParse, pLevel, pWC, notReady, nExtraReg, &zStartAff
-    );
-    zEndAff = sqlite3DbStrDup(pParse->db, zStartAff);
+    regBase = codeAllEqualityTerms(pParse,pLevel,bRev,nExtraReg,&zStartAff);
+    zEndAff = sqlite3DbStrDup(db, zStartAff);
     addrNxt = pLevel->addrNxt;
 
     /* If we are doing a reverse order scan on an ascending index, or
@@ -107790,10 +108314,10 @@ static Bitmask codeOneLoopStart(
       SWAP(WhereTerm *, pRangeEnd, pRangeStart);
     }
 
-    testcase( pRangeStart && pRangeStart->eOperator & WO_LE );
-    testcase( pRangeStart && pRangeStart->eOperator & WO_GE );
-    testcase( pRangeEnd && pRangeEnd->eOperator & WO_LE );
-    testcase( pRangeEnd && pRangeEnd->eOperator & WO_GE );
+    testcase( pRangeStart && (pRangeStart->eOperator & WO_LE)!=0 );
+    testcase( pRangeStart && (pRangeStart->eOperator & WO_GE)!=0 );
+    testcase( pRangeEnd && (pRangeEnd->eOperator & WO_LE)!=0 );
+    testcase( pRangeEnd && (pRangeEnd->eOperator & WO_GE)!=0 );
     startEq = !pRangeStart || pRangeStart->eOperator & (WO_LE|WO_GE);
     endEq =   !pRangeEnd || pRangeEnd->eOperator & (WO_LE|WO_GE);
     start_constraints = pRangeStart || nEq>0;
@@ -107818,7 +108342,7 @@ static Bitmask codeOneLoopStart(
         }
       }  
       nConstraint++;
-      testcase( pRangeStart->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
+      testcase( pRangeStart->wtFlags & TERM_VIRTUAL );
     }else if( isMinQuery ){
       sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
       nConstraint++;
@@ -107860,10 +108384,10 @@ static Bitmask codeOneLoopStart(
       }  
       codeApplyAffinity(pParse, regBase, nEq+1, zEndAff);
       nConstraint++;
-      testcase( pRangeEnd->wtFlags & TERM_VIRTUAL ); /* EV: R-30575-11662 */
+      testcase( pRangeEnd->wtFlags & TERM_VIRTUAL );
     }
-    sqlite3DbFree(pParse->db, zStartAff);
-    sqlite3DbFree(pParse->db, zEndAff);
+    sqlite3DbFree(db, zStartAff);
+    sqlite3DbFree(db, zEndAff);
 
     /* Top of the loop body */
     pLevel->p2 = sqlite3VdbeCurrentAddr(v);
@@ -107883,9 +108407,9 @@ static Bitmask codeOneLoopStart(
     ** If it is, jump to the next iteration of the loop.
     */
     r1 = sqlite3GetTempReg(pParse);
-    testcase( pLevel->plan.wsFlags & WHERE_BTM_LIMIT );
-    testcase( pLevel->plan.wsFlags & WHERE_TOP_LIMIT );
-    if( (pLevel->plan.wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0 ){
+    testcase( pLoop->wsFlags & WHERE_BTM_LIMIT );
+    testcase( pLoop->wsFlags & WHERE_TOP_LIMIT );
+    if( (pLoop->wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0 ){
       sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, nEq, r1);
       sqlite3VdbeAddOp2(v, OP_IsNull, r1, addrCont);
     }
@@ -107904,7 +108428,7 @@ static Bitmask codeOneLoopStart(
     /* Record the instruction used to terminate the loop. Disable 
     ** WHERE clause terms made redundant by the index range scan.
     */
-    if( pLevel->plan.wsFlags & WHERE_UNIQUE ){
+    if( pLoop->wsFlags & WHERE_ONEROW ){
       pLevel->op = OP_Noop;
     }else if( bRev ){
       pLevel->op = OP_Prev;
@@ -107912,11 +108436,16 @@ static Bitmask codeOneLoopStart(
       pLevel->op = OP_Next;
     }
     pLevel->p1 = iIdxCur;
+    if( (pLoop->wsFlags & WHERE_CONSTRAINT)==0 ){
+      pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP;
+    }else{
+      assert( pLevel->p5==0 );
+    }
   }else
 
 #ifndef SQLITE_OMIT_OR_OPTIMIZATION
-  if( pLevel->plan.wsFlags & WHERE_MULTI_OR ){
-    /* Case 4:  Two or more separately indexed terms connected by OR
+  if( pLoop->wsFlags & WHERE_MULTI_OR ){
+    /* Case 5:  Two or more separately indexed terms connected by OR
     **
     ** Example:
     **
@@ -107957,6 +108486,8 @@ static Bitmask codeOneLoopStart(
     */
     WhereClause *pOrWc;    /* The OR-clause broken out into subterms */
     SrcList *pOrTab;       /* Shortened table list or OR-clause generation */
+    Index *pCov = 0;             /* Potential covering index (or NULL) */
+    int iCovCur = pParse->nTab++;  /* Cursor used for index scans (if any) */
 
     int regReturn = ++pParse->nMem;           /* Register used with OP_Gosub */
     int regRowset = 0;                        /* Register for RowSet object */
@@ -107967,15 +108498,15 @@ static Bitmask codeOneLoopStart(
     int ii;                            /* Loop counter */
     Expr *pAndExpr = 0;                /* An ".. AND (...)" expression */
    
-    pTerm = pLevel->plan.u.pTerm;
+    pTerm = pLoop->aLTerm[0];
     assert( pTerm!=0 );
-    assert( pTerm->eOperator==WO_OR );
+    assert( pTerm->eOperator & WO_OR );
     assert( (pTerm->wtFlags & TERM_ORINFO)!=0 );
     pOrWc = &pTerm->u.pOrInfo->wc;
     pLevel->op = OP_Return;
     pLevel->p1 = regReturn;
 
-    /* Set up a new SrcList ni pOrTab containing the table being scanned
+    /* Set up a new SrcList in pOrTab containing the table being scanned
     ** by this loop in the a[0] slot and all notReady tables in a[1..] slots.
     ** This becomes the SrcList in the recursive call to sqlite3WhereBegin().
     */
@@ -107983,10 +108514,10 @@ static Bitmask codeOneLoopStart(
       int nNotReady;                 /* The number of notReady tables */
       struct SrcList_item *origSrc;     /* Original list of tables */
       nNotReady = pWInfo->nLevel - iLevel - 1;
-      pOrTab = sqlite3StackAllocRaw(pParse->db,
+      pOrTab = sqlite3StackAllocRaw(db,
                             sizeof(*pOrTab)+ nNotReady*sizeof(pOrTab->a[0]));
       if( pOrTab==0 ) return notReady;
-      pOrTab->nAlloc = (i16)(nNotReady + 1);
+      pOrTab->nAlloc = (u8)(nNotReady + 1);
       pOrTab->nSrc = pOrTab->nAlloc;
       memcpy(pOrTab->a, pTabItem, sizeof(*pTabItem));
       origSrc = pWInfo->pTabList->a;
@@ -108008,7 +108539,7 @@ static Bitmask codeOneLoopStart(
     ** fall through to the next instruction, just as an OP_Next does if
     ** called on an uninitialized cursor.
     */
-    if( (wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
+    if( (pWInfo->wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
       regRowset = ++pParse->nMem;
       regRowid = ++pParse->nMem;
       sqlite3VdbeAddOp2(v, OP_Null, 0, regRowset);
@@ -108024,16 +108555,21 @@ static Bitmask codeOneLoopStart(
     ** the "interesting" terms of z - terms that did not originate in the
     ** ON or USING clause of a LEFT JOIN, and terms that are usable as 
     ** indices.
+    **
+    ** This optimization also only applies if the (x1 OR x2 OR ...) term
+    ** is not contained in the ON clause of a LEFT JOIN.
+    ** See ticket http://www.sqlite.org/src/info/f2369304e4
     */
     if( pWC->nTerm>1 ){
       int iTerm;
       for(iTerm=0; iTerm<pWC->nTerm; iTerm++){
         Expr *pExpr = pWC->a[iTerm].pExpr;
+        if( &pWC->a[iTerm] == pTerm ) continue;
         if( ExprHasProperty(pExpr, EP_FromJoin) ) continue;
-        if( pWC->a[iTerm].wtFlags & (TERM_VIRTUAL|TERM_ORINFO) ) continue;
+        if( pWC->a[iTerm].wtFlags & (TERM_ORINFO) ) continue;
         if( (pWC->a[iTerm].eOperator & WO_ALL)==0 ) continue;
-        pExpr = sqlite3ExprDup(pParse->db, pExpr, 0);
-        pAndExpr = sqlite3ExprAnd(pParse->db, pAndExpr, pExpr);
+        pExpr = sqlite3ExprDup(db, pExpr, 0);
+        pAndExpr = sqlite3ExprAnd(db, pAndExpr, pExpr);
       }
       if( pAndExpr ){
         pAndExpr = sqlite3PExpr(pParse, TK_AND, 0, pAndExpr, 0);
@@ -108042,22 +108578,24 @@ static Bitmask codeOneLoopStart(
 
     for(ii=0; ii<pOrWc->nTerm; ii++){
       WhereTerm *pOrTerm = &pOrWc->a[ii];
-      if( pOrTerm->leftCursor==iCur || pOrTerm->eOperator==WO_AND ){
+      if( pOrTerm->leftCursor==iCur || (pOrTerm->eOperator & WO_AND)!=0 ){
         WhereInfo *pSubWInfo;          /* Info for single OR-term scan */
         Expr *pOrExpr = pOrTerm->pExpr;
-        if( pAndExpr ){
+        if( pAndExpr && !ExprHasProperty(pOrExpr, EP_FromJoin) ){
           pAndExpr->pLeft = pOrExpr;
           pOrExpr = pAndExpr;
         }
         /* Loop through table entries that match term pOrTerm. */
         pSubWInfo = sqlite3WhereBegin(pParse, pOrTab, pOrExpr, 0, 0,
                         WHERE_OMIT_OPEN_CLOSE | WHERE_AND_ONLY |
-                        WHERE_FORCE_TABLE | WHERE_ONETABLE_ONLY);
+                        WHERE_FORCE_TABLE | WHERE_ONETABLE_ONLY, iCovCur);
+        assert( pSubWInfo || pParse->nErr || db->mallocFailed );
         if( pSubWInfo ){
+          WhereLoop *pSubLoop;
           explainOneScan(
               pParse, pOrTab, &pSubWInfo->a[0], iLevel, pLevel->iFrom, 0
           );
-          if( (wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
+          if( (pWInfo->wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
             int iSet = ((ii==pOrWc->nTerm-1)?-1:ii);
             int r;
             r = sqlite3ExprCodeGetColumn(pParse, pTabItem->pTab, -1, iCur, 
@@ -108074,52 +108612,72 @@ static Bitmask codeOneLoopStart(
           */
           if( pSubWInfo->untestedTerms ) untestedTerms = 1;
 
+          /* If all of the OR-connected terms are optimized using the same
+          ** index, and the index is opened using the same cursor number
+          ** by each call to sqlite3WhereBegin() made by this loop, it may
+          ** be possible to use that index as a covering index.
+          **
+          ** If the call to sqlite3WhereBegin() above resulted in a scan that
+          ** uses an index, and this is either the first OR-connected term
+          ** processed or the index is the same as that used by all previous
+          ** terms, set pCov to the candidate covering index. Otherwise, set 
+          ** pCov to NULL to indicate that no candidate covering index will 
+          ** be available.
+          */
+          pSubLoop = pSubWInfo->a[0].pWLoop;
+          assert( (pSubLoop->wsFlags & WHERE_AUTO_INDEX)==0 );
+          if( (pSubLoop->wsFlags & WHERE_INDEXED)!=0
+           && (ii==0 || pSubLoop->u.btree.pIndex==pCov)
+          ){
+            assert( pSubWInfo->a[0].iIdxCur==iCovCur );
+            pCov = pSubLoop->u.btree.pIndex;
+          }else{
+            pCov = 0;
+          }
+
           /* Finish the loop through table entries that match term pOrTerm. */
           sqlite3WhereEnd(pSubWInfo);
         }
       }
     }
+    pLevel->u.pCovidx = pCov;
+    if( pCov ) pLevel->iIdxCur = iCovCur;
     if( pAndExpr ){
       pAndExpr->pLeft = 0;
-      sqlite3ExprDelete(pParse->db, pAndExpr);
+      sqlite3ExprDelete(db, pAndExpr);
     }
     sqlite3VdbeChangeP1(v, iRetInit, sqlite3VdbeCurrentAddr(v));
     sqlite3VdbeAddOp2(v, OP_Goto, 0, pLevel->addrBrk);
     sqlite3VdbeResolveLabel(v, iLoopBody);
 
-    if( pWInfo->nLevel>1 ) sqlite3StackFree(pParse->db, pOrTab);
+    if( pWInfo->nLevel>1 ) sqlite3StackFree(db, pOrTab);
     if( !untestedTerms ) disableTerm(pLevel, pTerm);
   }else
 #endif /* SQLITE_OMIT_OR_OPTIMIZATION */
 
   {
-    /* Case 5:  There is no usable index.  We must do a complete
+    /* Case 6:  There is no usable index.  We must do a complete
     **          scan of the entire table.
     */
     static const u8 aStep[] = { OP_Next, OP_Prev };
     static const u8 aStart[] = { OP_Rewind, OP_Last };
     assert( bRev==0 || bRev==1 );
-    assert( omitTable==0 );
     pLevel->op = aStep[bRev];
     pLevel->p1 = iCur;
     pLevel->p2 = 1 + sqlite3VdbeAddOp2(v, aStart[bRev], iCur, addrBrk);
     pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP;
   }
-  notReady &= ~getMask(pWC->pMaskSet, iCur);
+  newNotReady = notReady & ~getMask(&pWInfo->sMaskSet, iCur);
 
   /* Insert code to test every subexpression that can be completely
   ** computed using the current set of tables.
-  **
-  ** IMPLEMENTATION-OF: R-49525-50935 Terms that cannot be satisfied through
-  ** the use of indices become tests that are evaluated against each row of
-  ** the relevant input tables.
   */
   for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
     Expr *pE;
-    testcase( pTerm->wtFlags & TERM_VIRTUAL ); /* IMP: R-30575-11662 */
+    testcase( pTerm->wtFlags & TERM_VIRTUAL );
     testcase( pTerm->wtFlags & TERM_CODED );
     if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
-    if( (pTerm->prereqAll & notReady)!=0 ){
+    if( (pTerm->prereqAll & newNotReady)!=0 ){
       testcase( pWInfo->untestedTerms==0
                && (pWInfo->wctrlFlags & WHERE_ONETABLE_ONLY)!=0 );
       pWInfo->untestedTerms = 1;
@@ -108134,6 +108692,39 @@ static Bitmask codeOneLoopStart(
     pTerm->wtFlags |= TERM_CODED;
   }
 
+  /* Insert code to test for implied constraints based on transitivity
+  ** of the "==" operator.
+  **
+  ** Example: If the WHERE clause contains "t1.a=t2.b" and "t2.b=123"
+  ** and we are coding the t1 loop and the t2 loop has not yet coded,
+  ** then we cannot use the "t1.a=t2.b" constraint, but we can code
+  ** the implied "t1.a=123" constraint.
+  */
+  for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
+    Expr *pE, *pEAlt;
+    WhereTerm *pAlt;
+    if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
+    if( pTerm->eOperator!=(WO_EQUIV|WO_EQ) ) continue;
+    if( pTerm->leftCursor!=iCur ) continue;
+    if( pLevel->iLeftJoin ) continue;
+    pE = pTerm->pExpr;
+    assert( !ExprHasProperty(pE, EP_FromJoin) );
+    assert( (pTerm->prereqRight & newNotReady)!=0 );
+    pAlt = findTerm(pWC, iCur, pTerm->u.leftColumn, notReady, WO_EQ|WO_IN, 0);
+    if( pAlt==0 ) continue;
+    if( pAlt->wtFlags & (TERM_CODED) ) continue;
+    testcase( pAlt->eOperator & WO_EQ );
+    testcase( pAlt->eOperator & WO_IN );
+    VdbeNoopComment((v, "begin transitive constraint"));
+    pEAlt = sqlite3StackAllocRaw(db, sizeof(*pEAlt));
+    if( pEAlt ){
+      *pEAlt = *pAlt->pExpr;
+      pEAlt->pLeft = pE->pLeft;
+      sqlite3ExprIfFalse(pParse, pEAlt, addrCont, SQLITE_JUMPIFNULL);
+      sqlite3StackFree(db, pEAlt);
+    }
+  }
+
   /* For a LEFT OUTER JOIN, generate code that will record the fact that
   ** at least one row of the right table has matched the left table.  
   */
@@ -108143,10 +108734,10 @@ static Bitmask codeOneLoopStart(
     VdbeComment((v, "record LEFT JOIN hit"));
     sqlite3ExprCacheClear(pParse);
     for(pTerm=pWC->a, j=0; j<pWC->nTerm; j++, pTerm++){
-      testcase( pTerm->wtFlags & TERM_VIRTUAL );  /* IMP: R-30575-11662 */
+      testcase( pTerm->wtFlags & TERM_VIRTUAL );
       testcase( pTerm->wtFlags & TERM_CODED );
       if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
-      if( (pTerm->prereqAll & notReady)!=0 ){
+      if( (pTerm->prereqAll & newNotReady)!=0 ){
         assert( pWInfo->untestedTerms );
         continue;
       }
@@ -108157,50 +108748,1604 @@ static Bitmask codeOneLoopStart(
   }
   sqlite3ReleaseTempReg(pParse, iReleaseReg);
 
-  return notReady;
+  return newNotReady;
 }
 
-#if defined(SQLITE_TEST)
+#ifdef WHERETRACE_ENABLED
 /*
-** The following variable holds a text description of query plan generated
-** by the most recent call to sqlite3WhereBegin().  Each call to WhereBegin
-** overwrites the previous.  This information is used for testing and
-** analysis only.
+** Print a WhereLoop object for debugging purposes
 */
-SQLITE_API char sqlite3_query_plan[BMS*2*40];  /* Text of the join */
-static int nQPlan = 0;              /* Next free slow in _query_plan[] */
+static void whereLoopPrint(WhereLoop *p, SrcList *pTabList){
+  int nb = 1+(pTabList->nSrc+7)/8;
+  struct SrcList_item *pItem = pTabList->a + p->iTab;
+  Table *pTab = pItem->pTab;
+  sqlite3DebugPrintf("%c%2d.%0*llx.%0*llx", p->cId,
+                     p->iTab, nb, p->maskSelf, nb, p->prereq);
+  sqlite3DebugPrintf(" %12s",
+                     pItem->zAlias ? pItem->zAlias : pTab->zName);
+  if( (p->wsFlags & WHERE_VIRTUALTABLE)==0 ){
+    if( p->u.btree.pIndex ){
+      const char *zName = p->u.btree.pIndex->zName;
+      if( zName==0 ) zName = "ipk";
+      if( strncmp(zName, "sqlite_autoindex_", 17)==0 ){
+        int i = sqlite3Strlen30(zName) - 1;
+        while( zName[i]!='_' ) i--;
+        zName += i;
+      }
+      sqlite3DebugPrintf(".%-16s %2d", zName, p->u.btree.nEq);
+    }else{
+      sqlite3DebugPrintf("%20s","");
+    }
+  }else{
+    char *z;
+    if( p->u.vtab.idxStr ){
+      z = sqlite3_mprintf("(%d,\"%s\",%x)",
+                p->u.vtab.idxNum, p->u.vtab.idxStr, p->u.vtab.omitMask);
+    }else{
+      z = sqlite3_mprintf("(%d,%x)", p->u.vtab.idxNum, p->u.vtab.omitMask);
+    }
+    sqlite3DebugPrintf(" %-19s", z);
+    sqlite3_free(z);
+  }
+  sqlite3DebugPrintf(" f %04x N %d", p->wsFlags, p->nLTerm);
+  sqlite3DebugPrintf(" cost %d,%d,%d\n", p->rSetup, p->rRun, p->nOut);
+}
+#endif
 
-#endif /* SQLITE_TEST */
+/*
+** Convert bulk memory into a valid WhereLoop that can be passed
+** to whereLoopClear harmlessly.
+*/
+static void whereLoopInit(WhereLoop *p){
+  p->aLTerm = p->aLTermSpace;
+  p->nLTerm = 0;
+  p->nLSlot = ArraySize(p->aLTermSpace);
+  p->wsFlags = 0;
+}
 
+/*
+** Clear the WhereLoop.u union.  Leave WhereLoop.pLTerm intact.
+*/
+static void whereLoopClearUnion(sqlite3 *db, WhereLoop *p){
+  if( p->wsFlags & (WHERE_VIRTUALTABLE|WHERE_AUTO_INDEX) ){
+    if( (p->wsFlags & WHERE_VIRTUALTABLE)!=0 && p->u.vtab.needFree ){
+      sqlite3_free(p->u.vtab.idxStr);
+      p->u.vtab.needFree = 0;
+      p->u.vtab.idxStr = 0;
+    }else if( (p->wsFlags & WHERE_AUTO_INDEX)!=0 && p->u.btree.pIndex!=0 ){
+      sqlite3DbFree(db, p->u.btree.pIndex->zColAff);
+      sqlite3DbFree(db, p->u.btree.pIndex);
+      p->u.btree.pIndex = 0;
+    }
+  }
+}
+
+/*
+** Deallocate internal memory used by a WhereLoop object
+*/
+static void whereLoopClear(sqlite3 *db, WhereLoop *p){
+  if( p->aLTerm!=p->aLTermSpace ) sqlite3DbFree(db, p->aLTerm);
+  whereLoopClearUnion(db, p);
+  whereLoopInit(p);
+}
+
+/*
+** Increase the memory allocation for pLoop->aLTerm[] to be at least n.
+*/
+static int whereLoopResize(sqlite3 *db, WhereLoop *p, int n){
+  WhereTerm **paNew;
+  if( p->nLSlot>=n ) return SQLITE_OK;
+  n = (n+7)&~7;
+  paNew = sqlite3DbMallocRaw(db, sizeof(p->aLTerm[0])*n);
+  if( paNew==0 ) return SQLITE_NOMEM;
+  memcpy(paNew, p->aLTerm, sizeof(p->aLTerm[0])*p->nLSlot);
+  if( p->aLTerm!=p->aLTermSpace ) sqlite3DbFree(db, p->aLTerm);
+  p->aLTerm = paNew;
+  p->nLSlot = n;
+  return SQLITE_OK;
+}
+
+/*
+** Transfer content from the second pLoop into the first.
+*/
+static int whereLoopXfer(sqlite3 *db, WhereLoop *pTo, WhereLoop *pFrom){
+  if( whereLoopResize(db, pTo, pFrom->nLTerm) ) return SQLITE_NOMEM;
+  whereLoopClearUnion(db, pTo);
+  memcpy(pTo, pFrom, WHERE_LOOP_XFER_SZ);
+  memcpy(pTo->aLTerm, pFrom->aLTerm, pTo->nLTerm*sizeof(pTo->aLTerm[0]));
+  if( pFrom->wsFlags & WHERE_VIRTUALTABLE ){
+    pFrom->u.vtab.needFree = 0;
+  }else if( (pFrom->wsFlags & WHERE_AUTO_INDEX)!=0 ){
+    pFrom->u.btree.pIndex = 0;
+  }
+  return SQLITE_OK;
+}
+
+/*
+** Delete a WhereLoop object
+*/
+static void whereLoopDelete(sqlite3 *db, WhereLoop *p){
+  whereLoopClear(db, p);
+  sqlite3DbFree(db, p);
+}
 
 /*
 ** Free a WhereInfo structure
 */
 static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
   if( ALWAYS(pWInfo) ){
-    int i;
-    for(i=0; i<pWInfo->nLevel; i++){
-      sqlite3_index_info *pInfo = pWInfo->a[i].pIdxInfo;
-      if( pInfo ){
-        /* assert( pInfo->needToFreeIdxStr==0 || db->mallocFailed ); */
-        if( pInfo->needToFreeIdxStr ){
-          sqlite3_free(pInfo->idxStr);
-        }
-        sqlite3DbFree(db, pInfo);
-      }
-      if( pWInfo->a[i].plan.wsFlags & WHERE_TEMP_INDEX ){
-        Index *pIdx = pWInfo->a[i].plan.u.pIdx;
-        if( pIdx ){
-          sqlite3DbFree(db, pIdx->zColAff);
-          sqlite3DbFree(db, pIdx);
-        }
-      }
+    whereClauseClear(&pWInfo->sWC);
+    while( pWInfo->pLoops ){
+      WhereLoop *p = pWInfo->pLoops;
+      pWInfo->pLoops = p->pNextLoop;
+      whereLoopDelete(db, p);
     }
-    whereClauseClear(pWInfo->pWC);
     sqlite3DbFree(db, pWInfo);
   }
 }
 
+/*
+** Insert or replace a WhereLoop entry using the template supplied.
+**
+** An existing WhereLoop entry might be overwritten if the new template
+** is better and has fewer dependencies.  Or the template will be ignored
+** and no insert will occur if an existing WhereLoop is faster and has
+** fewer dependencies than the template.  Otherwise a new WhereLoop is
+** added based on the template.
+**
+** If pBuilder->pOrSet is not NULL then we only care about only the
+** prerequisites and rRun and nOut costs of the N best loops.  That
+** information is gathered in the pBuilder->pOrSet object.  This special
+** processing mode is used only for OR clause processing.
+**
+** When accumulating multiple loops (when pBuilder->pOrSet is NULL) we
+** still might overwrite similar loops with the new template if the
+** template is better.  Loops may be overwritten if the following 
+** conditions are met:
+**
+**    (1)  They have the same iTab.
+**    (2)  They have the same iSortIdx.
+**    (3)  The template has same or fewer dependencies than the current loop
+**    (4)  The template has the same or lower cost than the current loop
+**    (5)  The template uses more terms of the same index but has no additional
+**         dependencies          
+*/
+static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
+  WhereLoop **ppPrev, *p, *pNext = 0;
+  WhereInfo *pWInfo = pBuilder->pWInfo;
+  sqlite3 *db = pWInfo->pParse->db;
+
+  /* If pBuilder->pOrSet is defined, then only keep track of the costs
+  ** and prereqs.
+  */
+  if( pBuilder->pOrSet!=0 ){
+#if WHERETRACE_ENABLED
+    u16 n = pBuilder->pOrSet->n;
+    int x =
+#endif
+    whereOrInsert(pBuilder->pOrSet, pTemplate->prereq, pTemplate->rRun,
+                                    pTemplate->nOut);
+#if WHERETRACE_ENABLED
+    if( sqlite3WhereTrace & 0x8 ){
+      sqlite3DebugPrintf(x?"   or-%d:  ":"   or-X:  ", n);
+      whereLoopPrint(pTemplate, pWInfo->pTabList);
+    }
+#endif
+    return SQLITE_OK;
+  }
+
+  /* Search for an existing WhereLoop to overwrite, or which takes
+  ** priority over pTemplate.
+  */
+  for(ppPrev=&pWInfo->pLoops, p=*ppPrev; p; ppPrev=&p->pNextLoop, p=*ppPrev){
+    if( p->iTab!=pTemplate->iTab || p->iSortIdx!=pTemplate->iSortIdx ){
+      /* If either the iTab or iSortIdx values for two WhereLoop are different
+      ** then those WhereLoops need to be considered separately.  Neither is
+      ** a candidate to replace the other. */
+      continue;
+    }
+    /* In the current implementation, the rSetup value is either zero
+    ** or the cost of building an automatic index (NlogN) and the NlogN
+    ** is the same for compatible WhereLoops. */
+    assert( p->rSetup==0 || pTemplate->rSetup==0 
+                 || p->rSetup==pTemplate->rSetup );
+
+    /* whereLoopAddBtree() always generates and inserts the automatic index
+    ** case first.  Hence compatible candidate WhereLoops never have a larger
+    ** rSetup. Call this SETUP-INVARIANT */
+    assert( p->rSetup>=pTemplate->rSetup );
+
+    if( (p->prereq & pTemplate->prereq)==p->prereq
+     && p->rSetup<=pTemplate->rSetup
+     && p->rRun<=pTemplate->rRun
+    ){
+      /* This branch taken when p is equal or better than pTemplate in 
+      ** all of (1) dependences (2) setup-cost, and (3) run-cost. */
+      assert( p->rSetup==pTemplate->rSetup );
+      if( p->nLTerm<pTemplate->nLTerm
+       && (p->wsFlags & WHERE_INDEXED)!=0
+       && (pTemplate->wsFlags & WHERE_INDEXED)!=0
+       && p->u.btree.pIndex==pTemplate->u.btree.pIndex
+       && p->prereq==pTemplate->prereq
+      ){
+        /* Overwrite an existing WhereLoop with an similar one that uses
+        ** more terms of the index */
+        pNext = p->pNextLoop;
+        break;
+      }else{
+        /* pTemplate is not helpful.
+        ** Return without changing or adding anything */
+        goto whereLoopInsert_noop;
+      }
+    }
+    if( (p->prereq & pTemplate->prereq)==pTemplate->prereq
+     && p->rRun>=pTemplate->rRun
+     && ALWAYS(p->rSetup>=pTemplate->rSetup) /* See SETUP-INVARIANT above */
+    ){
+      /* Overwrite an existing WhereLoop with a better one: one that is
+      ** better at one of (1) dependences, (2) setup-cost, or (3) run-cost
+      ** and is no worse in any of those categories. */
+      pNext = p->pNextLoop;
+      break;
+    }
+  }
+
+  /* If we reach this point it means that either p[] should be overwritten
+  ** with pTemplate[] if p[] exists, or if p==NULL then allocate a new
+  ** WhereLoop and insert it.
+  */
+#if WHERETRACE_ENABLED
+  if( sqlite3WhereTrace & 0x8 ){
+    if( p!=0 ){
+      sqlite3DebugPrintf("ins-del:  ");
+      whereLoopPrint(p, pWInfo->pTabList);
+    }
+    sqlite3DebugPrintf("ins-new:  ");
+    whereLoopPrint(pTemplate, pWInfo->pTabList);
+  }
+#endif
+  if( p==0 ){
+    p = sqlite3DbMallocRaw(db, sizeof(WhereLoop));
+    if( p==0 ) return SQLITE_NOMEM;
+    whereLoopInit(p);
+  }
+  whereLoopXfer(db, p, pTemplate);
+  p->pNextLoop = pNext;
+  *ppPrev = p;
+  if( (p->wsFlags & WHERE_VIRTUALTABLE)==0 ){
+    Index *pIndex = p->u.btree.pIndex;
+    if( pIndex && pIndex->tnum==0 ){
+      p->u.btree.pIndex = 0;
+    }
+  }
+  return SQLITE_OK;
+
+  /* Jump here if the insert is a no-op */
+whereLoopInsert_noop:
+#if WHERETRACE_ENABLED
+  if( sqlite3WhereTrace & 0x8 ){
+    sqlite3DebugPrintf("ins-noop: ");
+    whereLoopPrint(pTemplate, pWInfo->pTabList);
+  }
+#endif
+  return SQLITE_OK;  
+}
+
+/*
+** We have so far matched pBuilder->pNew->u.btree.nEq terms of the index pIndex.
+** Try to match one more.
+**
+** If pProbe->tnum==0, that means pIndex is a fake index used for the
+** INTEGER PRIMARY KEY.
+*/
+static int whereLoopAddBtreeIndex(
+  WhereLoopBuilder *pBuilder,     /* The WhereLoop factory */
+  struct SrcList_item *pSrc,      /* FROM clause term being analyzed */
+  Index *pProbe,                  /* An index on pSrc */
+  WhereCost nInMul                /* log(Number of iterations due to IN) */
+){
+  WhereInfo *pWInfo = pBuilder->pWInfo;  /* WHERE analyse context */
+  Parse *pParse = pWInfo->pParse;        /* Parsing context */
+  sqlite3 *db = pParse->db;       /* Database connection malloc context */
+  WhereLoop *pNew;                /* Template WhereLoop under construction */
+  WhereTerm *pTerm;               /* A WhereTerm under consideration */
+  int opMask;                     /* Valid operators for constraints */
+  WhereScan scan;                 /* Iterator for WHERE terms */
+  Bitmask saved_prereq;           /* Original value of pNew->prereq */
+  u16 saved_nLTerm;               /* Original value of pNew->nLTerm */
+  int saved_nEq;                  /* Original value of pNew->u.btree.nEq */
+  u32 saved_wsFlags;              /* Original value of pNew->wsFlags */
+  WhereCost saved_nOut;           /* Original value of pNew->nOut */
+  int iCol;                       /* Index of the column in the table */
+  int rc = SQLITE_OK;             /* Return code */
+  WhereCost nRowEst;              /* Estimated index selectivity */
+  WhereCost rLogSize;             /* Logarithm of table size */
+  WhereTerm *pTop = 0, *pBtm = 0; /* Top and bottom range constraints */
+
+  pNew = pBuilder->pNew;
+  if( db->mallocFailed ) return SQLITE_NOMEM;
+
+  assert( (pNew->wsFlags & WHERE_VIRTUALTABLE)==0 );
+  assert( (pNew->wsFlags & WHERE_TOP_LIMIT)==0 );
+  if( pNew->wsFlags & WHERE_BTM_LIMIT ){
+    opMask = WO_LT|WO_LE;
+  }else if( pProbe->tnum<=0 || (pSrc->jointype & JT_LEFT)!=0 ){
+    opMask = WO_EQ|WO_IN|WO_GT|WO_GE|WO_LT|WO_LE;
+  }else{
+    opMask = WO_EQ|WO_IN|WO_ISNULL|WO_GT|WO_GE|WO_LT|WO_LE;
+  }
+  if( pProbe->bUnordered ) opMask &= ~(WO_GT|WO_GE|WO_LT|WO_LE);
+
+  assert( pNew->u.btree.nEq<=pProbe->nColumn );
+  if( pNew->u.btree.nEq < pProbe->nColumn ){
+    iCol = pProbe->aiColumn[pNew->u.btree.nEq];
+    nRowEst = whereCost(pProbe->aiRowEst[pNew->u.btree.nEq+1]);
+    if( nRowEst==0 && pProbe->onError==OE_None ) nRowEst = 1;
+  }else{
+    iCol = -1;
+    nRowEst = 0;
+  }
+  pTerm = whereScanInit(&scan, pBuilder->pWC, pSrc->iCursor, iCol,
+                        opMask, pProbe);
+  saved_nEq = pNew->u.btree.nEq;
+  saved_nLTerm = pNew->nLTerm;
+  saved_wsFlags = pNew->wsFlags;
+  saved_prereq = pNew->prereq;
+  saved_nOut = pNew->nOut;
+  pNew->rSetup = 0;
+  rLogSize = estLog(whereCost(pProbe->aiRowEst[0]));
+  for(; rc==SQLITE_OK && pTerm!=0; pTerm = whereScanNext(&scan)){
+    int nIn = 0;
+    if( pTerm->prereqRight & pNew->maskSelf ) continue;
+    if( (pTerm->eOperator==WO_ISNULL || (pTerm->wtFlags&TERM_VNULL)!=0)
+     && (iCol<0 || pSrc->pTab->aCol[iCol].notNull)
+    ){
+      continue; /* ignore IS [NOT] NULL constraints on NOT NULL columns */
+    }
+    pNew->wsFlags = saved_wsFlags;
+    pNew->u.btree.nEq = saved_nEq;
+    pNew->nLTerm = saved_nLTerm;
+    if( whereLoopResize(db, pNew, pNew->nLTerm+1) ) break; /* OOM */
+    pNew->aLTerm[pNew->nLTerm++] = pTerm;
+    pNew->prereq = (saved_prereq | pTerm->prereqRight) & ~pNew->maskSelf;
+    pNew->rRun = rLogSize; /* Baseline cost is log2(N).  Adjustments below */
+    if( pTerm->eOperator & WO_IN ){
+      Expr *pExpr = pTerm->pExpr;
+      pNew->wsFlags |= WHERE_COLUMN_IN;
+      if( ExprHasProperty(pExpr, EP_xIsSelect) ){
+        /* "x IN (SELECT ...)":  TUNING: the SELECT returns 25 rows */
+        nIn = 46;  assert( 46==whereCost(25) );
+      }else if( ALWAYS(pExpr->x.pList && pExpr->x.pList->nExpr) ){
+        /* "x IN (value, value, ...)" */
+        nIn = whereCost(pExpr->x.pList->nExpr);
+      }
+      pNew->rRun += nIn;
+      pNew->u.btree.nEq++;
+      pNew->nOut = nRowEst + nInMul + nIn;
+    }else if( pTerm->eOperator & (WO_EQ) ){
+      assert( (pNew->wsFlags & (WHERE_COLUMN_NULL|WHERE_COLUMN_IN))!=0
+                  || nInMul==0 );
+      pNew->wsFlags |= WHERE_COLUMN_EQ;
+      if( iCol<0  
+       || (pProbe->onError!=OE_None && nInMul==0
+           && pNew->u.btree.nEq==pProbe->nColumn-1)
+      ){
+        assert( (pNew->wsFlags & WHERE_COLUMN_IN)==0 || iCol<0 );
+        pNew->wsFlags |= WHERE_ONEROW;
+      }
+      pNew->u.btree.nEq++;
+      pNew->nOut = nRowEst + nInMul;
+    }else if( pTerm->eOperator & (WO_ISNULL) ){
+      pNew->wsFlags |= WHERE_COLUMN_NULL;
+      pNew->u.btree.nEq++;
+      /* TUNING: IS NULL selects 2 rows */
+      nIn = 10;  assert( 10==whereCost(2) );
+      pNew->nOut = nRowEst + nInMul + nIn;
+    }else if( pTerm->eOperator & (WO_GT|WO_GE) ){
+      testcase( pTerm->eOperator & WO_GT );
+      testcase( pTerm->eOperator & WO_GE );
+      pNew->wsFlags |= WHERE_COLUMN_RANGE|WHERE_BTM_LIMIT;
+      pBtm = pTerm;
+      pTop = 0;
+    }else{
+      assert( pTerm->eOperator & (WO_LT|WO_LE) );
+      testcase( pTerm->eOperator & WO_LT );
+      testcase( pTerm->eOperator & WO_LE );
+      pNew->wsFlags |= WHERE_COLUMN_RANGE|WHERE_TOP_LIMIT;
+      pTop = pTerm;
+      pBtm = (pNew->wsFlags & WHERE_BTM_LIMIT)!=0 ?
+                     pNew->aLTerm[pNew->nLTerm-2] : 0;
+    }
+    if( pNew->wsFlags & WHERE_COLUMN_RANGE ){
+      /* Adjust nOut and rRun for STAT3 range values */
+      WhereCost rDiv;
+      whereRangeScanEst(pParse, pProbe, pNew->u.btree.nEq,
+                        pBtm, pTop, &rDiv);
+      pNew->nOut = saved_nOut>rDiv+10 ? saved_nOut - rDiv : 10;
+    }
+#ifdef SQLITE_ENABLE_STAT3
+    if( pNew->u.btree.nEq==1 && pProbe->nSample
+     &&  OptimizationEnabled(db, SQLITE_Stat3) ){
+      tRowcnt nOut = 0;
+      if( (pTerm->eOperator & (WO_EQ|WO_ISNULL))!=0 ){
+        testcase( pTerm->eOperator & WO_EQ );
+        testcase( pTerm->eOperator & WO_ISNULL );
+        rc = whereEqualScanEst(pParse, pProbe, pTerm->pExpr->pRight, &nOut);
+      }else if( (pTerm->eOperator & WO_IN)
+             &&  !ExprHasProperty(pTerm->pExpr, EP_xIsSelect)  ){
+        rc = whereInScanEst(pParse, pProbe, pTerm->pExpr->x.pList, &nOut);
+      }
+      assert( nOut==0 || rc==SQLITE_OK );
+      if( nOut ) pNew->nOut = whereCost(nOut);
+    }
+#endif
+    if( (pNew->wsFlags & (WHERE_IDX_ONLY|WHERE_IPK))==0 ){
+      /* Each row involves a step of the index, then a binary search of
+      ** the main table */
+      pNew->rRun =  whereCostAdd(pNew->rRun, rLogSize>27 ? rLogSize-17 : 10);
+    }
+    /* Step cost for each output row */
+    pNew->rRun = whereCostAdd(pNew->rRun, pNew->nOut);
+    /* TBD: Adjust nOut for additional constraints */
+    rc = whereLoopInsert(pBuilder, pNew);
+    if( (pNew->wsFlags & WHERE_TOP_LIMIT)==0
+     && pNew->u.btree.nEq<(pProbe->nColumn + (pProbe->zName!=0))
+    ){
+      whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, nInMul+nIn);
+    }
+  }
+  pNew->prereq = saved_prereq;
+  pNew->u.btree.nEq = saved_nEq;
+  pNew->wsFlags = saved_wsFlags;
+  pNew->nOut = saved_nOut;
+  pNew->nLTerm = saved_nLTerm;
+  return rc;
+}
+
+/*
+** Return True if it is possible that pIndex might be useful in
+** implementing the ORDER BY clause in pBuilder.
+**
+** Return False if pBuilder does not contain an ORDER BY clause or
+** if there is no way for pIndex to be useful in implementing that
+** ORDER BY clause.
+*/
+static int indexMightHelpWithOrderBy(
+  WhereLoopBuilder *pBuilder,
+  Index *pIndex,
+  int iCursor
+){
+  ExprList *pOB;
+  int ii, jj;
+
+  if( pIndex->bUnordered ) return 0;
+  if( (pOB = pBuilder->pWInfo->pOrderBy)==0 ) return 0;
+  for(ii=0; ii<pOB->nExpr; ii++){
+    Expr *pExpr = sqlite3ExprSkipCollate(pOB->a[ii].pExpr);
+    if( pExpr->op!=TK_COLUMN ) return 0;
+    if( pExpr->iTable==iCursor ){
+      for(jj=0; jj<pIndex->nColumn; jj++){
+        if( pExpr->iColumn==pIndex->aiColumn[jj] ) return 1;
+      }
+    }
+  }
+  return 0;
+}
+
+/*
+** Return a bitmask where 1s indicate that the corresponding column of
+** the table is used by an index.  Only the first 63 columns are considered.
+*/
+static Bitmask columnsInIndex(Index *pIdx){
+  Bitmask m = 0;
+  int j;
+  for(j=pIdx->nColumn-1; j>=0; j--){
+    int x = pIdx->aiColumn[j];
+    assert( x>=0 );
+    testcase( x==BMS-1 );
+    testcase( x==BMS-2 );
+    if( x<BMS-1 ) m |= MASKBIT(x);
+  }
+  return m;
+}
+
+/* Check to see if a partial index with pPartIndexWhere can be used
+** in the current query.  Return true if it can be and false if not.
+*/
+static int whereUsablePartialIndex(int iTab, WhereClause *pWC, Expr *pWhere){
+  int i;
+  WhereTerm *pTerm;
+  for(i=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
+    if( sqlite3ExprImpliesExpr(pTerm->pExpr, pWhere, iTab) ) return 1;
+  }
+  return 0;
+}
+
+/*
+** Add all WhereLoop objects for a single table of the join where the table
+** is idenfied by pBuilder->pNew->iTab.  That table is guaranteed to be
+** a b-tree table, not a virtual table.
+*/
+static int whereLoopAddBtree(
+  WhereLoopBuilder *pBuilder, /* WHERE clause information */
+  Bitmask mExtra              /* Extra prerequesites for using this table */
+){
+  WhereInfo *pWInfo;          /* WHERE analysis context */
+  Index *pProbe;              /* An index we are evaluating */
+  Index sPk;                  /* A fake index object for the primary key */
+  tRowcnt aiRowEstPk[2];      /* The aiRowEst[] value for the sPk index */
+  int aiColumnPk = -1;        /* The aColumn[] value for the sPk index */
+  SrcList *pTabList;          /* The FROM clause */
+  struct SrcList_item *pSrc;  /* The FROM clause btree term to add */
+  WhereLoop *pNew;            /* Template WhereLoop object */
+  int rc = SQLITE_OK;         /* Return code */
+  int iSortIdx = 1;           /* Index number */
+  int b;                      /* A boolean value */
+  WhereCost rSize;            /* number of rows in the table */
+  WhereCost rLogSize;         /* Logarithm of the number of rows in the table */
+  WhereClause *pWC;           /* The parsed WHERE clause */
+  
+  pNew = pBuilder->pNew;
+  pWInfo = pBuilder->pWInfo;
+  pTabList = pWInfo->pTabList;
+  pSrc = pTabList->a + pNew->iTab;
+  pWC = pBuilder->pWC;
+  assert( !IsVirtual(pSrc->pTab) );
+
+  if( pSrc->pIndex ){
+    /* An INDEXED BY clause specifies a particular index to use */
+    pProbe = pSrc->pIndex;
+  }else{
+    /* There is no INDEXED BY clause.  Create a fake Index object in local
+    ** variable sPk to represent the rowid primary key index.  Make this
+    ** fake index the first in a chain of Index objects with all of the real
+    ** indices to follow */
+    Index *pFirst;                  /* First of real indices on the table */
+    memset(&sPk, 0, sizeof(Index));
+    sPk.nColumn = 1;
+    sPk.aiColumn = &aiColumnPk;
+    sPk.aiRowEst = aiRowEstPk;
+    sPk.onError = OE_Replace;
+    sPk.pTable = pSrc->pTab;
+    aiRowEstPk[0] = pSrc->pTab->nRowEst;
+    aiRowEstPk[1] = 1;
+    pFirst = pSrc->pTab->pIndex;
+    if( pSrc->notIndexed==0 ){
+      /* The real indices of the table are only considered if the
+      ** NOT INDEXED qualifier is omitted from the FROM clause */
+      sPk.pNext = pFirst;
+    }
+    pProbe = &sPk;
+  }
+  rSize = whereCost(pSrc->pTab->nRowEst);
+  rLogSize = estLog(rSize);
+
+#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
+  /* Automatic indexes */
+  if( !pBuilder->pOrSet
+   && (pWInfo->pParse->db->flags & SQLITE_AutoIndex)!=0
+   && pSrc->pIndex==0
+   && !pSrc->viaCoroutine
+   && !pSrc->notIndexed
+   && !pSrc->isCorrelated
+  ){
+    /* Generate auto-index WhereLoops */
+    WhereTerm *pTerm;
+    WhereTerm *pWCEnd = pWC->a + pWC->nTerm;
+    for(pTerm=pWC->a; rc==SQLITE_OK && pTerm<pWCEnd; pTerm++){
+      if( pTerm->prereqRight & pNew->maskSelf ) continue;
+      if( termCanDriveIndex(pTerm, pSrc, 0) ){
+        pNew->u.btree.nEq = 1;
+        pNew->u.btree.pIndex = 0;
+        pNew->nLTerm = 1;
+        pNew->aLTerm[0] = pTerm;
+        /* TUNING: One-time cost for computing the automatic index is
+        ** approximately 7*N*log2(N) where N is the number of rows in
+        ** the table being indexed. */
+        pNew->rSetup = rLogSize + rSize + 28;  assert( 28==whereCost(7) );
+        /* TUNING: Each index lookup yields 20 rows in the table.  This
+        ** is more than the usual guess of 10 rows, since we have no way
+        ** of knowning how selective the index will ultimately be.  It would
+        ** not be unreasonable to make this value much larger. */
+        pNew->nOut = 43;  assert( 43==whereCost(20) );
+        pNew->rRun = whereCostAdd(rLogSize,pNew->nOut);
+        pNew->wsFlags = WHERE_AUTO_INDEX;
+        pNew->prereq = mExtra | pTerm->prereqRight;
+        rc = whereLoopInsert(pBuilder, pNew);
+      }
+    }
+  }
+#endif /* SQLITE_OMIT_AUTOMATIC_INDEX */
+
+  /* Loop over all indices
+  */
+  for(; rc==SQLITE_OK && pProbe; pProbe=pProbe->pNext, iSortIdx++){
+    if( pProbe->pPartIdxWhere!=0
+     && !whereUsablePartialIndex(pNew->iTab, pWC, pProbe->pPartIdxWhere) ){
+      continue;  /* Partial index inappropriate for this query */
+    }
+    pNew->u.btree.nEq = 0;
+    pNew->nLTerm = 0;
+    pNew->iSortIdx = 0;
+    pNew->rSetup = 0;
+    pNew->prereq = mExtra;
+    pNew->nOut = rSize;
+    pNew->u.btree.pIndex = pProbe;
+    b = indexMightHelpWithOrderBy(pBuilder, pProbe, pSrc->iCursor);
+    /* The ONEPASS_DESIRED flags never occurs together with ORDER BY */
+    assert( (pWInfo->wctrlFlags & WHERE_ONEPASS_DESIRED)==0 || b==0 );
+    if( pProbe->tnum<=0 ){
+      /* Integer primary key index */
+      pNew->wsFlags = WHERE_IPK;
+
+      /* Full table scan */
+      pNew->iSortIdx = b ? iSortIdx : 0;
+      /* TUNING: Cost of full table scan is 3*(N + log2(N)).
+      **  +  The extra 3 factor is to encourage the use of indexed lookups
+      **     over full scans.  A smaller constant 2 is used for covering
+      **     index scans so that a covering index scan will be favored over
+      **     a table scan. */
+      pNew->rRun = whereCostAdd(rSize,rLogSize) + 16;
+      rc = whereLoopInsert(pBuilder, pNew);
+      if( rc ) break;
+    }else{
+      Bitmask m = pSrc->colUsed & ~columnsInIndex(pProbe);
+      pNew->wsFlags = (m==0) ? (WHERE_IDX_ONLY|WHERE_INDEXED) : WHERE_INDEXED;
+
+      /* Full scan via index */
+      if( b
+       || ( m==0
+         && pProbe->bUnordered==0
+         && (pWInfo->wctrlFlags & WHERE_ONEPASS_DESIRED)==0
+         && sqlite3GlobalConfig.bUseCis
+         && OptimizationEnabled(pWInfo->pParse->db, SQLITE_CoverIdxScan)
+          )
+      ){
+        pNew->iSortIdx = b ? iSortIdx : 0;
+        if( m==0 ){
+          /* TUNING: Cost of a covering index scan is 2*(N + log2(N)).
+          **  +  The extra 2 factor is to encourage the use of indexed lookups
+          **     over index scans.  A table scan uses a factor of 3 so that
+          **     index scans are favored over table scans.
+          **  +  If this covering index might also help satisfy the ORDER BY
+          **     clause, then the cost is fudged down slightly so that this
+          **     index is favored above other indices that have no hope of
+          **     helping with the ORDER BY. */
+          pNew->rRun = 10 + whereCostAdd(rSize,rLogSize) - b;
+        }else{
+          assert( b!=0 ); 
+          /* TUNING: Cost of scanning a non-covering index is (N+1)*log2(N)
+          ** which we will simplify to just N*log2(N) */
+          pNew->rRun = rSize + rLogSize;
+        }
+        rc = whereLoopInsert(pBuilder, pNew);
+        if( rc ) break;
+      }
+    }
+    rc = whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, 0);
+
+    /* If there was an INDEXED BY clause, then only that one index is
+    ** considered. */
+    if( pSrc->pIndex ) break;
+  }
+  return rc;
+}
+
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+/*
+** Add all WhereLoop objects for a table of the join identified by
+** pBuilder->pNew->iTab.  That table is guaranteed to be a virtual table.
+*/
+static int whereLoopAddVirtual(
+  WhereLoopBuilder *pBuilder   /* WHERE clause information */
+){
+  WhereInfo *pWInfo;           /* WHERE analysis context */
+  Parse *pParse;               /* The parsing context */
+  WhereClause *pWC;            /* The WHERE clause */
+  struct SrcList_item *pSrc;   /* The FROM clause term to search */
+  Table *pTab;
+  sqlite3 *db;
+  sqlite3_index_info *pIdxInfo;
+  struct sqlite3_index_constraint *pIdxCons;
+  struct sqlite3_index_constraint_usage *pUsage;
+  WhereTerm *pTerm;
+  int i, j;
+  int iTerm, mxTerm;
+  int nConstraint;
+  int seenIn = 0;              /* True if an IN operator is seen */
+  int seenVar = 0;             /* True if a non-constant constraint is seen */
+  int iPhase;                  /* 0: const w/o IN, 1: const, 2: no IN,  2: IN */
+  WhereLoop *pNew;
+  int rc = SQLITE_OK;
+
+  pWInfo = pBuilder->pWInfo;
+  pParse = pWInfo->pParse;
+  db = pParse->db;
+  pWC = pBuilder->pWC;
+  pNew = pBuilder->pNew;
+  pSrc = &pWInfo->pTabList->a[pNew->iTab];
+  pTab = pSrc->pTab;
+  assert( IsVirtual(pTab) );
+  pIdxInfo = allocateIndexInfo(pParse, pWC, pSrc, pBuilder->pOrderBy);
+  if( pIdxInfo==0 ) return SQLITE_NOMEM;
+  pNew->prereq = 0;
+  pNew->rSetup = 0;
+  pNew->wsFlags = WHERE_VIRTUALTABLE;
+  pNew->nLTerm = 0;
+  pNew->u.vtab.needFree = 0;
+  pUsage = pIdxInfo->aConstraintUsage;
+  nConstraint = pIdxInfo->nConstraint;
+  if( whereLoopResize(db, pNew, nConstraint) ){
+    sqlite3DbFree(db, pIdxInfo);
+    return SQLITE_NOMEM;
+  }
+
+  for(iPhase=0; iPhase<=3; iPhase++){
+    if( !seenIn && (iPhase&1)!=0 ){
+      iPhase++;
+      if( iPhase>3 ) break;
+    }
+    if( !seenVar && iPhase>1 ) break;
+    pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
+    for(i=0; i<pIdxInfo->nConstraint; i++, pIdxCons++){
+      j = pIdxCons->iTermOffset;
+      pTerm = &pWC->a[j];
+      switch( iPhase ){
+        case 0:    /* Constants without IN operator */
+          pIdxCons->usable = 0;
+          if( (pTerm->eOperator & WO_IN)!=0 ){
+            seenIn = 1;
+          }
+          if( pTerm->prereqRight!=0 ){
+            seenVar = 1;
+          }else if( (pTerm->eOperator & WO_IN)==0 ){
+            pIdxCons->usable = 1;
+          }
+          break;
+        case 1:    /* Constants with IN operators */
+          assert( seenIn );
+          pIdxCons->usable = (pTerm->prereqRight==0);
+          break;
+        case 2:    /* Variables without IN */
+          assert( seenVar );
+          pIdxCons->usable = (pTerm->eOperator & WO_IN)==0;
+          break;
+        default:   /* Variables with IN */
+          assert( seenVar && seenIn );
+          pIdxCons->usable = 1;
+          break;
+      }
+    }
+    memset(pUsage, 0, sizeof(pUsage[0])*pIdxInfo->nConstraint);
+    if( pIdxInfo->needToFreeIdxStr ) sqlite3_free(pIdxInfo->idxStr);
+    pIdxInfo->idxStr = 0;
+    pIdxInfo->idxNum = 0;
+    pIdxInfo->needToFreeIdxStr = 0;
+    pIdxInfo->orderByConsumed = 0;
+    pIdxInfo->estimatedCost = SQLITE_BIG_DBL / (double)2;
+    rc = vtabBestIndex(pParse, pTab, pIdxInfo);
+    if( rc ) goto whereLoopAddVtab_exit;
+    pIdxCons = *(struct sqlite3_index_constraint**)&pIdxInfo->aConstraint;
+    pNew->prereq = 0;
+    mxTerm = -1;
+    assert( pNew->nLSlot>=nConstraint );
+    for(i=0; i<nConstraint; i++) pNew->aLTerm[i] = 0;
+    pNew->u.vtab.omitMask = 0;
+    for(i=0; i<nConstraint; i++, pIdxCons++){
+      if( (iTerm = pUsage[i].argvIndex - 1)>=0 ){
+        j = pIdxCons->iTermOffset;
+        if( iTerm>=nConstraint
+         || j<0
+         || j>=pWC->nTerm
+         || pNew->aLTerm[iTerm]!=0
+        ){
+          rc = SQLITE_ERROR;
+          sqlite3ErrorMsg(pParse, "%s.xBestIndex() malfunction", pTab->zName);
+          goto whereLoopAddVtab_exit;
+        }
+        testcase( iTerm==nConstraint-1 );
+        testcase( j==0 );
+        testcase( j==pWC->nTerm-1 );
+        pTerm = &pWC->a[j];
+        pNew->prereq |= pTerm->prereqRight;
+        assert( iTerm<pNew->nLSlot );
+        pNew->aLTerm[iTerm] = pTerm;
+        if( iTerm>mxTerm ) mxTerm = iTerm;
+        testcase( iTerm==15 );
+        testcase( iTerm==16 );
+        if( iTerm<16 && pUsage[i].omit ) pNew->u.vtab.omitMask |= 1<<iTerm;
+        if( (pTerm->eOperator & WO_IN)!=0 ){
+          if( pUsage[i].omit==0 ){
+            /* Do not attempt to use an IN constraint if the virtual table
+            ** says that the equivalent EQ constraint cannot be safely omitted.
+            ** If we do attempt to use such a constraint, some rows might be
+            ** repeated in the output. */
+            break;
+          }
+          /* A virtual table that is constrained by an IN clause may not
+          ** consume the ORDER BY clause because (1) the order of IN terms
+          ** is not necessarily related to the order of output terms and
+          ** (2) Multiple outputs from a single IN value will not merge
+          ** together.  */
+          pIdxInfo->orderByConsumed = 0;
+        }
+      }
+    }
+    if( i>=nConstraint ){
+      pNew->nLTerm = mxTerm+1;
+      assert( pNew->nLTerm<=pNew->nLSlot );
+      pNew->u.vtab.idxNum = pIdxInfo->idxNum;
+      pNew->u.vtab.needFree = pIdxInfo->needToFreeIdxStr;
+      pIdxInfo->needToFreeIdxStr = 0;
+      pNew->u.vtab.idxStr = pIdxInfo->idxStr;
+      pNew->u.vtab.isOrdered = (u8)((pIdxInfo->nOrderBy!=0)
+                                     && pIdxInfo->orderByConsumed);
+      pNew->rSetup = 0;
+      pNew->rRun = whereCostFromDouble(pIdxInfo->estimatedCost);
+      /* TUNING: Every virtual table query returns 25 rows */
+      pNew->nOut = 46;  assert( 46==whereCost(25) );
+      whereLoopInsert(pBuilder, pNew);
+      if( pNew->u.vtab.needFree ){
+        sqlite3_free(pNew->u.vtab.idxStr);
+        pNew->u.vtab.needFree = 0;
+      }
+    }
+  }  
+
+whereLoopAddVtab_exit:
+  if( pIdxInfo->needToFreeIdxStr ) sqlite3_free(pIdxInfo->idxStr);
+  sqlite3DbFree(db, pIdxInfo);
+  return rc;
+}
+#endif /* SQLITE_OMIT_VIRTUALTABLE */
+
+/*
+** Add WhereLoop entries to handle OR terms.  This works for either
+** btrees or virtual tables.
+*/
+static int whereLoopAddOr(WhereLoopBuilder *pBuilder, Bitmask mExtra){
+  WhereInfo *pWInfo = pBuilder->pWInfo;
+  WhereClause *pWC;
+  WhereLoop *pNew;
+  WhereTerm *pTerm, *pWCEnd;
+  int rc = SQLITE_OK;
+  int iCur;
+  WhereClause tempWC;
+  WhereLoopBuilder sSubBuild;
+  WhereOrSet sSum, sCur, sPrev;
+  struct SrcList_item *pItem;
+  
+  pWC = pBuilder->pWC;
+  if( pWInfo->wctrlFlags & WHERE_AND_ONLY ) return SQLITE_OK;
+  pWCEnd = pWC->a + pWC->nTerm;
+  pNew = pBuilder->pNew;
+  memset(&sSum, 0, sizeof(sSum));
+
+  for(pTerm=pWC->a; pTerm<pWCEnd && rc==SQLITE_OK; pTerm++){
+    if( (pTerm->eOperator & WO_OR)!=0
+     && (pTerm->u.pOrInfo->indexable & pNew->maskSelf)!=0 
+    ){
+      WhereClause * const pOrWC = &pTerm->u.pOrInfo->wc;
+      WhereTerm * const pOrWCEnd = &pOrWC->a[pOrWC->nTerm];
+      WhereTerm *pOrTerm;
+      int once = 1;
+      int i, j;
+    
+      pItem = pWInfo->pTabList->a + pNew->iTab;
+      iCur = pItem->iCursor;
+      sSubBuild = *pBuilder;
+      sSubBuild.pOrderBy = 0;
+      sSubBuild.pOrSet = &sCur;
+
+      for(pOrTerm=pOrWC->a; pOrTerm<pOrWCEnd; pOrTerm++){
+        if( (pOrTerm->eOperator & WO_AND)!=0 ){
+          sSubBuild.pWC = &pOrTerm->u.pAndInfo->wc;
+        }else if( pOrTerm->leftCursor==iCur ){
+          tempWC.pWInfo = pWC->pWInfo;
+          tempWC.pOuter = pWC;
+          tempWC.op = TK_AND;
+          tempWC.nTerm = 1;
+          tempWC.a = pOrTerm;
+          sSubBuild.pWC = &tempWC;
+        }else{
+          continue;
+        }
+        sCur.n = 0;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+        if( IsVirtual(pItem->pTab) ){
+          rc = whereLoopAddVirtual(&sSubBuild);
+          for(i=0; i<sCur.n; i++) sCur.a[i].prereq |= mExtra;
+        }else
+#endif
+        {
+          rc = whereLoopAddBtree(&sSubBuild, mExtra);
+        }
+        assert( rc==SQLITE_OK || sCur.n==0 );
+        if( sCur.n==0 ){
+          sSum.n = 0;
+          break;
+        }else if( once ){
+          whereOrMove(&sSum, &sCur);
+          once = 0;
+        }else{
+          whereOrMove(&sPrev, &sSum);
+          sSum.n = 0;
+          for(i=0; i<sPrev.n; i++){
+            for(j=0; j<sCur.n; j++){
+              whereOrInsert(&sSum, sPrev.a[i].prereq | sCur.a[j].prereq,
+                            whereCostAdd(sPrev.a[i].rRun, sCur.a[j].rRun),
+                            whereCostAdd(sPrev.a[i].nOut, sCur.a[j].nOut));
+            }
+          }
+        }
+      }
+      pNew->nLTerm = 1;
+      pNew->aLTerm[0] = pTerm;
+      pNew->wsFlags = WHERE_MULTI_OR;
+      pNew->rSetup = 0;
+      pNew->iSortIdx = 0;
+      memset(&pNew->u, 0, sizeof(pNew->u));
+      for(i=0; rc==SQLITE_OK && i<sSum.n; i++){
+        /* TUNING: Multiple by 3.5 for the secondary table lookup */
+        pNew->rRun = sSum.a[i].rRun + 18;
+        pNew->nOut = sSum.a[i].nOut;
+        pNew->prereq = sSum.a[i].prereq;
+        rc = whereLoopInsert(pBuilder, pNew);
+      }
+    }
+  }
+  return rc;
+}
+
+/*
+** Add all WhereLoop objects for all tables 
+*/
+static int whereLoopAddAll(WhereLoopBuilder *pBuilder){
+  WhereInfo *pWInfo = pBuilder->pWInfo;
+  Bitmask mExtra = 0;
+  Bitmask mPrior = 0;
+  int iTab;
+  SrcList *pTabList = pWInfo->pTabList;
+  struct SrcList_item *pItem;
+  sqlite3 *db = pWInfo->pParse->db;
+  int nTabList = pWInfo->nLevel;
+  int rc = SQLITE_OK;
+  u8 priorJoinType = 0;
+  WhereLoop *pNew;
+
+  /* Loop over the tables in the join, from left to right */
+  pNew = pBuilder->pNew;
+  whereLoopInit(pNew);
+  for(iTab=0, pItem=pTabList->a; iTab<nTabList; iTab++, pItem++){
+    pNew->iTab = iTab;
+    pNew->maskSelf = getMask(&pWInfo->sMaskSet, pItem->iCursor);
+    if( ((pItem->jointype|priorJoinType) & (JT_LEFT|JT_CROSS))!=0 ){
+      mExtra = mPrior;
+    }
+    priorJoinType = pItem->jointype;
+    if( IsVirtual(pItem->pTab) ){
+      rc = whereLoopAddVirtual(pBuilder);
+    }else{
+      rc = whereLoopAddBtree(pBuilder, mExtra);
+    }
+    if( rc==SQLITE_OK ){
+      rc = whereLoopAddOr(pBuilder, mExtra);
+    }
+    mPrior |= pNew->maskSelf;
+    if( rc || db->mallocFailed ) break;
+  }
+  whereLoopClear(db, pNew);
+  return rc;
+}
+
+/*
+** Examine a WherePath (with the addition of the extra WhereLoop of the 5th
+** parameters) to see if it outputs rows in the requested ORDER BY
+** (or GROUP BY) without requiring a separate sort operation.  Return:
+** 
+**    0:  ORDER BY is not satisfied.  Sorting required
+**    1:  ORDER BY is satisfied.      Omit sorting
+**   -1:  Unknown at this time
+**
+** Note that processing for WHERE_GROUPBY and WHERE_DISTINCTBY is not as
+** strict.  With GROUP BY and DISTINCT the only requirement is that
+** equivalent rows appear immediately adjacent to one another.  GROUP BY
+** and DISTINT do not require rows to appear in any particular order as long
+** as equivelent rows are grouped together.  Thus for GROUP BY and DISTINCT
+** the pOrderBy terms can be matched in any order.  With ORDER BY, the 
+** pOrderBy terms must be matched in strict left-to-right order.
+*/
+static int wherePathSatisfiesOrderBy(
+  WhereInfo *pWInfo,    /* The WHERE clause */
+  ExprList *pOrderBy,   /* ORDER BY or GROUP BY or DISTINCT clause to check */
+  WherePath *pPath,     /* The WherePath to check */
+  u16 wctrlFlags,       /* Might contain WHERE_GROUPBY or WHERE_DISTINCTBY */
+  u16 nLoop,            /* Number of entries in pPath->aLoop[] */
+  WhereLoop *pLast,     /* Add this WhereLoop to the end of pPath->aLoop[] */
+  Bitmask *pRevMask     /* OUT: Mask of WhereLoops to run in reverse order */
+){
+  u8 revSet;            /* True if rev is known */
+  u8 rev;               /* Composite sort order */
+  u8 revIdx;            /* Index sort order */
+  u8 isOrderDistinct;   /* All prior WhereLoops are order-distinct */
+  u8 distinctColumns;   /* True if the loop has UNIQUE NOT NULL columns */
+  u8 isMatch;           /* iColumn matches a term of the ORDER BY clause */
+  u16 nColumn;          /* Number of columns in pIndex */
+  u16 nOrderBy;         /* Number terms in the ORDER BY clause */
+  int iLoop;            /* Index of WhereLoop in pPath being processed */
+  int i, j;             /* Loop counters */
+  int iCur;             /* Cursor number for current WhereLoop */
+  int iColumn;          /* A column number within table iCur */
+  WhereLoop *pLoop = 0; /* Current WhereLoop being processed. */
+  WhereTerm *pTerm;     /* A single term of the WHERE clause */
+  Expr *pOBExpr;        /* An expression from the ORDER BY clause */
+  CollSeq *pColl;       /* COLLATE function from an ORDER BY clause term */
+  Index *pIndex;        /* The index associated with pLoop */
+  sqlite3 *db = pWInfo->pParse->db;  /* Database connection */
+  Bitmask obSat = 0;    /* Mask of ORDER BY terms satisfied so far */
+  Bitmask obDone;       /* Mask of all ORDER BY terms */
+  Bitmask orderDistinctMask;  /* Mask of all well-ordered loops */
+  Bitmask ready;              /* Mask of inner loops */
+
+  /*
+  ** We say the WhereLoop is "one-row" if it generates no more than one
+  ** row of output.  A WhereLoop is one-row if all of the following are true:
+  **  (a) All index columns match with WHERE_COLUMN_EQ.
+  **  (b) The index is unique
+  ** Any WhereLoop with an WHERE_COLUMN_EQ constraint on the rowid is one-row.
+  ** Every one-row WhereLoop will have the WHERE_ONEROW bit set in wsFlags.
+  **
+  ** We say the WhereLoop is "order-distinct" if the set of columns from
+  ** that WhereLoop that are in the ORDER BY clause are different for every
+  ** row of the WhereLoop.  Every one-row WhereLoop is automatically
+  ** order-distinct.   A WhereLoop that has no columns in the ORDER BY clause
+  ** is not order-distinct. To be order-distinct is not quite the same as being
+  ** UNIQUE since a UNIQUE column or index can have multiple rows that 
+  ** are NULL and NULL values are equivalent for the purpose of order-distinct.
+  ** To be order-distinct, the columns must be UNIQUE and NOT NULL.
+  **
+  ** The rowid for a table is always UNIQUE and NOT NULL so whenever the
+  ** rowid appears in the ORDER BY clause, the corresponding WhereLoop is
+  ** automatically order-distinct.
+  */
+
+  assert( pOrderBy!=0 );
+
+  /* Sortability of virtual tables is determined by the xBestIndex method
+  ** of the virtual table itself */
+  if( pLast->wsFlags & WHERE_VIRTUALTABLE ){
+    testcase( nLoop>0 );  /* True when outer loops are one-row and match 
+                          ** no ORDER BY terms */
+    return pLast->u.vtab.isOrdered;
+  }
+  if( nLoop && OptimizationDisabled(db, SQLITE_OrderByIdxJoin) ) return 0;
+
+  nOrderBy = pOrderBy->nExpr;
+  testcase( nOrderBy==BMS-1 );
+  if( nOrderBy>BMS-1 ) return 0;  /* Cannot optimize overly large ORDER BYs */
+  isOrderDistinct = 1;
+  obDone = MASKBIT(nOrderBy)-1;
+  orderDistinctMask = 0;
+  ready = 0;
+  for(iLoop=0; isOrderDistinct && obSat<obDone && iLoop<=nLoop; iLoop++){
+    if( iLoop>0 ) ready |= pLoop->maskSelf;
+    pLoop = iLoop<nLoop ? pPath->aLoop[iLoop] : pLast;
+    assert( (pLoop->wsFlags & WHERE_VIRTUALTABLE)==0 );
+    iCur = pWInfo->pTabList->a[pLoop->iTab].iCursor;
+
+    /* Mark off any ORDER BY term X that is a column in the table of
+    ** the current loop for which there is term in the WHERE
+    ** clause of the form X IS NULL or X=? that reference only outer
+    ** loops.
+    */
+    for(i=0; i<nOrderBy; i++){
+      if( MASKBIT(i) & obSat ) continue;
+      pOBExpr = sqlite3ExprSkipCollate(pOrderBy->a[i].pExpr);
+      if( pOBExpr->op!=TK_COLUMN ) continue;
+      if( pOBExpr->iTable!=iCur ) continue;
+      pTerm = findTerm(&pWInfo->sWC, iCur, pOBExpr->iColumn,
+                       ~ready, WO_EQ|WO_ISNULL, 0);
+      if( pTerm==0 ) continue;
+      if( (pTerm->eOperator&WO_EQ)!=0 && pOBExpr->iColumn>=0 ){
+        const char *z1, *z2;
+        pColl = sqlite3ExprCollSeq(pWInfo->pParse, pOrderBy->a[i].pExpr);
+        if( !pColl ) pColl = db->pDfltColl;
+        z1 = pColl->zName;
+        pColl = sqlite3ExprCollSeq(pWInfo->pParse, pTerm->pExpr);
+        if( !pColl ) pColl = db->pDfltColl;
+        z2 = pColl->zName;
+        if( sqlite3StrICmp(z1, z2)!=0 ) continue;
+      }
+      obSat |= MASKBIT(i);
+    }
+
+    if( (pLoop->wsFlags & WHERE_ONEROW)==0 ){
+      if( pLoop->wsFlags & WHERE_IPK ){
+        pIndex = 0;
+        nColumn = 0;
+      }else if( (pIndex = pLoop->u.btree.pIndex)==0 || pIndex->bUnordered ){
+        return 0;
+      }else{
+        nColumn = pIndex->nColumn;
+        isOrderDistinct = pIndex->onError!=OE_None;
+      }
+
+      /* Loop through all columns of the index and deal with the ones
+      ** that are not constrained by == or IN.
+      */
+      rev = revSet = 0;
+      distinctColumns = 0;
+      for(j=0; j<=nColumn; j++){
+        u8 bOnce;   /* True to run the ORDER BY search loop */
+
+        /* Skip over == and IS NULL terms */
+        if( j<pLoop->u.btree.nEq
+         && ((i = pLoop->aLTerm[j]->eOperator) & (WO_EQ|WO_ISNULL))!=0
+        ){
+          if( i & WO_ISNULL ){
+            testcase( isOrderDistinct );
+            isOrderDistinct = 0;
+          }
+          continue;  
+        }
+
+        /* Get the column number in the table (iColumn) and sort order
+        ** (revIdx) for the j-th column of the index.
+        */
+        if( j<nColumn ){
+          /* Normal index columns */
+          iColumn = pIndex->aiColumn[j];
+          revIdx = pIndex->aSortOrder[j];
+          if( iColumn==pIndex->pTable->iPKey ) iColumn = -1;
+        }else{
+          /* The ROWID column at the end */
+          assert( j==nColumn );
+          iColumn = -1;
+          revIdx = 0;
+        }
+
+        /* An unconstrained column that might be NULL means that this
+        ** WhereLoop is not well-ordered 
+        */
+        if( isOrderDistinct
+         && iColumn>=0
+         && j>=pLoop->u.btree.nEq
+         && pIndex->pTable->aCol[iColumn].notNull==0
+        ){
+          isOrderDistinct = 0;
+        }
+
+        /* Find the ORDER BY term that corresponds to the j-th column
+        ** of the index and and mark that ORDER BY term off 
+        */
+        bOnce = 1;
+        isMatch = 0;
+        for(i=0; bOnce && i<nOrderBy; i++){
+          if( MASKBIT(i) & obSat ) continue;
+          pOBExpr = sqlite3ExprSkipCollate(pOrderBy->a[i].pExpr);
+          testcase( wctrlFlags & WHERE_GROUPBY );
+          testcase( wctrlFlags & WHERE_DISTINCTBY );
+          if( (wctrlFlags & (WHERE_GROUPBY|WHERE_DISTINCTBY))==0 ) bOnce = 0;
+          if( pOBExpr->op!=TK_COLUMN ) continue;
+          if( pOBExpr->iTable!=iCur ) continue;
+          if( pOBExpr->iColumn!=iColumn ) continue;
+          if( iColumn>=0 ){
+            pColl = sqlite3ExprCollSeq(pWInfo->pParse, pOrderBy->a[i].pExpr);
+            if( !pColl ) pColl = db->pDfltColl;
+            if( sqlite3StrICmp(pColl->zName, pIndex->azColl[j])!=0 ) continue;
+          }
+          isMatch = 1;
+          break;
+        }
+        if( isMatch ){
+          if( iColumn<0 ){
+            testcase( distinctColumns==0 );
+            distinctColumns = 1;
+          }
+          obSat |= MASKBIT(i);
+          if( (pWInfo->wctrlFlags & WHERE_GROUPBY)==0 ){
+            /* Make sure the sort order is compatible in an ORDER BY clause.
+            ** Sort order is irrelevant for a GROUP BY clause. */
+            if( revSet ){
+              if( (rev ^ revIdx)!=pOrderBy->a[i].sortOrder ) return 0;
+            }else{
+              rev = revIdx ^ pOrderBy->a[i].sortOrder;
+              if( rev ) *pRevMask |= MASKBIT(iLoop);
+              revSet = 1;
+            }
+          }
+        }else{
+          /* No match found */
+          if( j==0 || j<nColumn ){
+            testcase( isOrderDistinct!=0 );
+            isOrderDistinct = 0;
+          }
+          break;
+        }
+      } /* end Loop over all index columns */
+      if( distinctColumns ){
+        testcase( isOrderDistinct==0 );
+        isOrderDistinct = 1;
+      }
+    } /* end-if not one-row */
+
+    /* Mark off any other ORDER BY terms that reference pLoop */
+    if( isOrderDistinct ){
+      orderDistinctMask |= pLoop->maskSelf;
+      for(i=0; i<nOrderBy; i++){
+        Expr *p;
+        if( MASKBIT(i) & obSat ) continue;
+        p = pOrderBy->a[i].pExpr;
+        if( (exprTableUsage(&pWInfo->sMaskSet, p)&~orderDistinctMask)==0 ){
+          obSat |= MASKBIT(i);
+        }
+      }
+    }
+  } /* End the loop over all WhereLoops from outer-most down to inner-most */
+  if( obSat==obDone ) return 1;
+  if( !isOrderDistinct ) return 0;
+  return -1;
+}
+
+#ifdef WHERETRACE_ENABLED
+/* For debugging use only: */
+static const char *wherePathName(WherePath *pPath, int nLoop, WhereLoop *pLast){
+  static char zName[65];
+  int i;
+  for(i=0; i<nLoop; i++){ zName[i] = pPath->aLoop[i]->cId; }
+  if( pLast ) zName[i++] = pLast->cId;
+  zName[i] = 0;
+  return zName;
+}
+#endif
+
+
+/*
+** Given the list of WhereLoop objects at pWInfo->pLoops, this routine
+** attempts to find the lowest cost path that visits each WhereLoop
+** once.  This path is then loaded into the pWInfo->a[].pWLoop fields.
+**
+** Assume that the total number of output rows that will need to be sorted
+** will be nRowEst (in the 10*log2 representation).  Or, ignore sorting
+** costs if nRowEst==0.
+**
+** Return SQLITE_OK on success or SQLITE_NOMEM of a memory allocation
+** error occurs.
+*/
+static int wherePathSolver(WhereInfo *pWInfo, WhereCost nRowEst){
+  int mxChoice;             /* Maximum number of simultaneous paths tracked */
+  int nLoop;                /* Number of terms in the join */
+  Parse *pParse;            /* Parsing context */
+  sqlite3 *db;              /* The database connection */
+  int iLoop;                /* Loop counter over the terms of the join */
+  int ii, jj;               /* Loop counters */
+  WhereCost rCost;             /* Cost of a path */
+  WhereCost mxCost = 0;        /* Maximum cost of a set of paths */
+  WhereCost rSortCost;         /* Cost to do a sort */
+  int nTo, nFrom;           /* Number of valid entries in aTo[] and aFrom[] */
+  WherePath *aFrom;         /* All nFrom paths at the previous level */
+  WherePath *aTo;           /* The nTo best paths at the current level */
+  WherePath *pFrom;         /* An element of aFrom[] that we are working on */
+  WherePath *pTo;           /* An element of aTo[] that we are working on */
+  WhereLoop *pWLoop;        /* One of the WhereLoop objects */
+  WhereLoop **pX;           /* Used to divy up the pSpace memory */
+  char *pSpace;             /* Temporary memory used by this routine */
+
+  pParse = pWInfo->pParse;
+  db = pParse->db;
+  nLoop = pWInfo->nLevel;
+  /* TUNING: For simple queries, only the best path is tracked.
+  ** For 2-way joins, the 5 best paths are followed.
+  ** For joins of 3 or more tables, track the 10 best paths */
+  mxChoice = (nLoop==1) ? 1 : (nLoop==2 ? 5 : 10);
+  assert( nLoop<=pWInfo->pTabList->nSrc );
+  WHERETRACE(0x002, ("---- begin solver\n"));
+
+  /* Allocate and initialize space for aTo and aFrom */
+  ii = (sizeof(WherePath)+sizeof(WhereLoop*)*nLoop)*mxChoice*2;
+  pSpace = sqlite3DbMallocRaw(db, ii);
+  if( pSpace==0 ) return SQLITE_NOMEM;
+  aTo = (WherePath*)pSpace;
+  aFrom = aTo+mxChoice;
+  memset(aFrom, 0, sizeof(aFrom[0]));
+  pX = (WhereLoop**)(aFrom+mxChoice);
+  for(ii=mxChoice*2, pFrom=aTo; ii>0; ii--, pFrom++, pX += nLoop){
+    pFrom->aLoop = pX;
+  }
+
+  /* Seed the search with a single WherePath containing zero WhereLoops.
+  **
+  ** TUNING: Do not let the number of iterations go above 25.  If the cost
+  ** of computing an automatic index is not paid back within the first 25
+  ** rows, then do not use the automatic index. */
+  aFrom[0].nRow = MIN(pParse->nQueryLoop, 46);  assert( 46==whereCost(25) );
+  nFrom = 1;
+
+  /* Precompute the cost of sorting the final result set, if the caller
+  ** to sqlite3WhereBegin() was concerned about sorting */
+  rSortCost = 0;
+  if( pWInfo->pOrderBy==0 || nRowEst==0 ){
+    aFrom[0].isOrderedValid = 1;
+  }else{
+    /* TUNING: Estimated cost of sorting is N*log2(N) where N is the
+    ** number of output rows. */
+    rSortCost = nRowEst + estLog(nRowEst);
+    WHERETRACE(0x002,("---- sort cost=%-3d\n", rSortCost));
+  }
+
+  /* Compute successively longer WherePaths using the previous generation
+  ** of WherePaths as the basis for the next.  Keep track of the mxChoice
+  ** best paths at each generation */
+  for(iLoop=0; iLoop<nLoop; iLoop++){
+    nTo = 0;
+    for(ii=0, pFrom=aFrom; ii<nFrom; ii++, pFrom++){
+      for(pWLoop=pWInfo->pLoops; pWLoop; pWLoop=pWLoop->pNextLoop){
+        Bitmask maskNew;
+        Bitmask revMask = 0;
+        u8 isOrderedValid = pFrom->isOrderedValid;
+        u8 isOrdered = pFrom->isOrdered;
+        if( (pWLoop->prereq & ~pFrom->maskLoop)!=0 ) continue;
+        if( (pWLoop->maskSelf & pFrom->maskLoop)!=0 ) continue;
+        /* At this point, pWLoop is a candidate to be the next loop. 
+        ** Compute its cost */
+        rCost = whereCostAdd(pWLoop->rSetup,pWLoop->rRun + pFrom->nRow);
+        rCost = whereCostAdd(rCost, pFrom->rCost);
+        maskNew = pFrom->maskLoop | pWLoop->maskSelf;
+        if( !isOrderedValid ){
+          switch( wherePathSatisfiesOrderBy(pWInfo,
+                       pWInfo->pOrderBy, pFrom, pWInfo->wctrlFlags,
+                       iLoop, pWLoop, &revMask) ){
+            case 1:  /* Yes.  pFrom+pWLoop does satisfy the ORDER BY clause */
+              isOrdered = 1;
+              isOrderedValid = 1;
+              break;
+            case 0:  /* No.  pFrom+pWLoop will require a separate sort */
+              isOrdered = 0;
+              isOrderedValid = 1;
+              rCost = whereCostAdd(rCost, rSortCost);
+              break;
+            default: /* Cannot tell yet.  Try again on the next iteration */
+              break;
+          }
+        }else{
+          revMask = pFrom->revLoop;
+        }
+        /* Check to see if pWLoop should be added to the mxChoice best so far */
+        for(jj=0, pTo=aTo; jj<nTo; jj++, pTo++){
+          if( pTo->maskLoop==maskNew && pTo->isOrderedValid==isOrderedValid ){
+            testcase( jj==nTo-1 );
+            break;
+          }
+        }
+        if( jj>=nTo ){
+          if( nTo>=mxChoice && rCost>=mxCost ){
+#ifdef WHERETRACE_ENABLED
+            if( sqlite3WhereTrace&0x4 ){
+              sqlite3DebugPrintf("Skip   %s cost=%3d order=%c\n",
+                  wherePathName(pFrom, iLoop, pWLoop), rCost,
+                  isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
+            }
+#endif
+            continue;
+          }
+          /* Add a new Path to the aTo[] set */
+          if( nTo<mxChoice ){
+            /* Increase the size of the aTo set by one */
+            jj = nTo++;
+          }else{
+            /* New path replaces the prior worst to keep count below mxChoice */
+            for(jj=nTo-1; aTo[jj].rCost<mxCost; jj--){ assert(jj>0); }
+          }
+          pTo = &aTo[jj];
+#ifdef WHERETRACE_ENABLED
+          if( sqlite3WhereTrace&0x4 ){
+            sqlite3DebugPrintf("New    %s cost=%-3d order=%c\n",
+                wherePathName(pFrom, iLoop, pWLoop), rCost,
+                isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
+          }
+#endif
+        }else{
+          if( pTo->rCost<=rCost ){
+#ifdef WHERETRACE_ENABLED
+            if( sqlite3WhereTrace&0x4 ){
+              sqlite3DebugPrintf(
+                  "Skip   %s cost=%-3d order=%c",
+                  wherePathName(pFrom, iLoop, pWLoop), rCost,
+                  isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
+              sqlite3DebugPrintf("   vs %s cost=%-3d order=%c\n",
+                  wherePathName(pTo, iLoop+1, 0), pTo->rCost,
+                  pTo->isOrderedValid ? (pTo->isOrdered ? 'Y' : 'N') : '?');
+            }
+#endif
+            testcase( pTo->rCost==rCost );
+            continue;
+          }
+          testcase( pTo->rCost==rCost+1 );
+          /* A new and better score for a previously created equivalent path */
+#ifdef WHERETRACE_ENABLED
+          if( sqlite3WhereTrace&0x4 ){
+            sqlite3DebugPrintf(
+                "Update %s cost=%-3d order=%c",
+                wherePathName(pFrom, iLoop, pWLoop), rCost,
+                isOrderedValid ? (isOrdered ? 'Y' : 'N') : '?');
+            sqlite3DebugPrintf("  was %s cost=%-3d order=%c\n",
+                wherePathName(pTo, iLoop+1, 0), pTo->rCost,
+                pTo->isOrderedValid ? (pTo->isOrdered ? 'Y' : 'N') : '?');
+          }
+#endif
+        }
+        /* pWLoop is a winner.  Add it to the set of best so far */
+        pTo->maskLoop = pFrom->maskLoop | pWLoop->maskSelf;
+        pTo->revLoop = revMask;
+        pTo->nRow = pFrom->nRow + pWLoop->nOut;
+        pTo->rCost = rCost;
+        pTo->isOrderedValid = isOrderedValid;
+        pTo->isOrdered = isOrdered;
+        memcpy(pTo->aLoop, pFrom->aLoop, sizeof(WhereLoop*)*iLoop);
+        pTo->aLoop[iLoop] = pWLoop;
+        if( nTo>=mxChoice ){
+          mxCost = aTo[0].rCost;
+          for(jj=1, pTo=&aTo[1]; jj<mxChoice; jj++, pTo++){
+            if( pTo->rCost>mxCost ) mxCost = pTo->rCost;
+          }
+        }
+      }
+    }
+
+#ifdef WHERETRACE_ENABLED
+    if( sqlite3WhereTrace>=2 ){
+      sqlite3DebugPrintf("---- after round %d ----\n", iLoop);
+      for(ii=0, pTo=aTo; ii<nTo; ii++, pTo++){
+        sqlite3DebugPrintf(" %s cost=%-3d nrow=%-3d order=%c",
+           wherePathName(pTo, iLoop+1, 0), pTo->rCost, pTo->nRow,
+           pTo->isOrderedValid ? (pTo->isOrdered ? 'Y' : 'N') : '?');
+        if( pTo->isOrderedValid && pTo->isOrdered ){
+          sqlite3DebugPrintf(" rev=0x%llx\n", pTo->revLoop);
+        }else{
+          sqlite3DebugPrintf("\n");
+        }
+      }
+    }
+#endif
+
+    /* Swap the roles of aFrom and aTo for the next generation */
+    pFrom = aTo;
+    aTo = aFrom;
+    aFrom = pFrom;
+    nFrom = nTo;
+  }
+
+  if( nFrom==0 ){
+    sqlite3ErrorMsg(pParse, "no query solution");
+    sqlite3DbFree(db, pSpace);
+    return SQLITE_ERROR;
+  }
+  
+  /* Find the lowest cost path.  pFrom will be left pointing to that path */
+  pFrom = aFrom;
+  assert( nFrom==1 );
+#if 0 /* The following is needed if nFrom is ever more than 1 */
+  for(ii=1; ii<nFrom; ii++){
+    if( pFrom->rCost>aFrom[ii].rCost ) pFrom = &aFrom[ii];
+  }
+#endif
+  assert( pWInfo->nLevel==nLoop );
+  /* Load the lowest cost path into pWInfo */
+  for(iLoop=0; iLoop<nLoop; iLoop++){
+    WhereLevel *pLevel = pWInfo->a + iLoop;
+    pLevel->pWLoop = pWLoop = pFrom->aLoop[iLoop];
+    pLevel->iFrom = pWLoop->iTab;
+    pLevel->iTabCur = pWInfo->pTabList->a[pLevel->iFrom].iCursor;
+  }
+  if( (pWInfo->wctrlFlags & WHERE_WANT_DISTINCT)!=0
+   && (pWInfo->wctrlFlags & WHERE_DISTINCTBY)==0
+   && pWInfo->eDistinct==WHERE_DISTINCT_NOOP
+   && nRowEst
+  ){
+    Bitmask notUsed;
+    int rc = wherePathSatisfiesOrderBy(pWInfo, pWInfo->pResultSet, pFrom,
+                 WHERE_DISTINCTBY, nLoop-1, pFrom->aLoop[nLoop-1], &notUsed);
+    if( rc==1 ) pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
+  }
+  if( pFrom->isOrdered ){
+    if( pWInfo->wctrlFlags & WHERE_DISTINCTBY ){
+      pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
+    }else{
+      pWInfo->bOBSat = 1;
+      pWInfo->revMask = pFrom->revLoop;
+    }
+  }
+  pWInfo->nRowOut = pFrom->nRow;
+
+  /* Free temporary memory and return success */
+  sqlite3DbFree(db, pSpace);
+  return SQLITE_OK;
+}
+
+/*
+** Most queries use only a single table (they are not joins) and have
+** simple == constraints against indexed fields.  This routine attempts
+** to plan those simple cases using much less ceremony than the
+** general-purpose query planner, and thereby yield faster sqlite3_prepare()
+** times for the common case.
+**
+** Return non-zero on success, if this query can be handled by this
+** no-frills query planner.  Return zero if this query needs the 
+** general-purpose query planner.
+*/
+static int whereShortCut(WhereLoopBuilder *pBuilder){
+  WhereInfo *pWInfo;
+  struct SrcList_item *pItem;
+  WhereClause *pWC;
+  WhereTerm *pTerm;
+  WhereLoop *pLoop;
+  int iCur;
+  int j;
+  Table *pTab;
+  Index *pIdx;
+  
+  pWInfo = pBuilder->pWInfo;
+  if( pWInfo->wctrlFlags & WHERE_FORCE_TABLE ) return 0;
+  assert( pWInfo->pTabList->nSrc>=1 );
+  pItem = pWInfo->pTabList->a;
+  pTab = pItem->pTab;
+  if( IsVirtual(pTab) ) return 0;
+  if( pItem->zIndex ) return 0;
+  iCur = pItem->iCursor;
+  pWC = &pWInfo->sWC;
+  pLoop = pBuilder->pNew;
+  pLoop->wsFlags = 0;
+  pTerm = findTerm(pWC, iCur, -1, 0, WO_EQ, 0);
+  if( pTerm ){
+    pLoop->wsFlags = WHERE_COLUMN_EQ|WHERE_IPK|WHERE_ONEROW;
+    pLoop->aLTerm[0] = pTerm;
+    pLoop->nLTerm = 1;
+    pLoop->u.btree.nEq = 1;
+    /* TUNING: Cost of a rowid lookup is 10 */
+    pLoop->rRun = 33;  /* 33==whereCost(10) */
+  }else{
+    for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
+      assert( pLoop->aLTermSpace==pLoop->aLTerm );
+      assert( ArraySize(pLoop->aLTermSpace)==4 );
+      if( pIdx->onError==OE_None 
+       || pIdx->pPartIdxWhere!=0 
+       || pIdx->nColumn>ArraySize(pLoop->aLTermSpace) 
+      ) continue;
+      for(j=0; j<pIdx->nColumn; j++){
+        pTerm = findTerm(pWC, iCur, pIdx->aiColumn[j], 0, WO_EQ, pIdx);
+        if( pTerm==0 ) break;
+        pLoop->aLTerm[j] = pTerm;
+      }
+      if( j!=pIdx->nColumn ) continue;
+      pLoop->wsFlags = WHERE_COLUMN_EQ|WHERE_ONEROW|WHERE_INDEXED;
+      if( (pItem->colUsed & ~columnsInIndex(pIdx))==0 ){
+        pLoop->wsFlags |= WHERE_IDX_ONLY;
+      }
+      pLoop->nLTerm = j;
+      pLoop->u.btree.nEq = j;
+      pLoop->u.btree.pIndex = pIdx;
+      /* TUNING: Cost of a unique index lookup is 15 */
+      pLoop->rRun = 39;  /* 39==whereCost(15) */
+      break;
+    }
+  }
+  if( pLoop->wsFlags ){
+    pLoop->nOut = (WhereCost)1;
+    pWInfo->a[0].pWLoop = pLoop;
+    pLoop->maskSelf = getMask(&pWInfo->sMaskSet, iCur);
+    pWInfo->a[0].iTabCur = iCur;
+    pWInfo->nRowOut = 1;
+    if( pWInfo->pOrderBy ) pWInfo->bOBSat =  1;
+    if( pWInfo->wctrlFlags & WHERE_WANT_DISTINCT ){
+      pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
+    }
+#ifdef SQLITE_DEBUG
+    pLoop->cId = '0';
+#endif
+    return 1;
+  }
+  return 0;
+}
 
 /*
 ** Generate the beginning of the loop used for WHERE clause processing.
@@ -108277,40 +110422,44 @@ static void whereInfoFree(sqlite3 *db, WhereInfo *pWInfo){
 **
 ** ORDER BY CLAUSE PROCESSING
 **
-** *ppOrderBy is a pointer to the ORDER BY clause of a SELECT statement,
+** pOrderBy is a pointer to the ORDER BY clause (or the GROUP BY clause
+** if the WHERE_GROUPBY flag is set in wctrlFlags) of a SELECT statement
 ** if there is one.  If there is no ORDER BY clause or if this routine
-** is called from an UPDATE or DELETE statement, then ppOrderBy is NULL.
-**
-** If an index can be used so that the natural output order of the table
-** scan is correct for the ORDER BY clause, then that index is used and
-** *ppOrderBy is set to NULL.  This is an optimization that prevents an
-** unnecessary sort of the result set if an index appropriate for the
-** ORDER BY clause already exists.
-**
-** If the where clause loops cannot be arranged to provide the correct
-** output order, then the *ppOrderBy is unchanged.
+** is called from an UPDATE or DELETE statement, then pOrderBy is NULL.
 */
 SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   Parse *pParse,        /* The parser context */
-  SrcList *pTabList,    /* A list of all tables to be scanned */
+  SrcList *pTabList,    /* FROM clause: A list of all tables to be scanned */
   Expr *pWhere,         /* The WHERE clause */
-  ExprList **ppOrderBy, /* An ORDER BY clause, or NULL */
-  ExprList *pDistinct,  /* The select-list for DISTINCT queries - or NULL */
-  u16 wctrlFlags        /* One of the WHERE_* flags defined in sqliteInt.h */
+  ExprList *pOrderBy,   /* An ORDER BY clause, or NULL */
+  ExprList *pResultSet, /* Result set of the query */
+  u16 wctrlFlags,       /* One of the WHERE_* flags defined in sqliteInt.h */
+  int iIdxCur           /* If WHERE_ONETABLE_ONLY is set, index cursor number */
 ){
-  int i;                     /* Loop counter */
   int nByteWInfo;            /* Num. bytes allocated for WhereInfo struct */
   int nTabList;              /* Number of elements in pTabList */
   WhereInfo *pWInfo;         /* Will become the return value of this function */
   Vdbe *v = pParse->pVdbe;   /* The virtual database engine */
   Bitmask notReady;          /* Cursors that are not yet positioned */
+  WhereLoopBuilder sWLB;     /* The WhereLoop builder */
   WhereMaskSet *pMaskSet;    /* The expression mask set */
-  WhereClause *pWC;               /* Decomposition of the WHERE clause */
-  struct SrcList_item *pTabItem;  /* A single entry from pTabList */
-  WhereLevel *pLevel;             /* A single level in the pWInfo list */
-  int iFrom;                      /* First unused FROM clause element */
-  int andFlags;              /* AND-ed combination of all pWC->a[].wtFlags */
+  WhereLevel *pLevel;        /* A single level in pWInfo->a[] */
+  WhereLoop *pLoop;          /* Pointer to a single WhereLoop object */
+  int ii;                    /* Loop counter */
   sqlite3 *db;               /* Database connection */
+  int rc;                    /* Return code */
+
+
+  /* Variable initialization */
+  db = pParse->db;
+  memset(&sWLB, 0, sizeof(sWLB));
+  sWLB.pOrderBy = pOrderBy;
+
+  /* Disable the DISTINCT optimization if SQLITE_DistinctOpt is set via
+  ** sqlite3_test_ctrl(SQLITE_TESTCTRL_OPTIMIZATIONS,...) */
+  if( OptimizationDisabled(db, SQLITE_DistinctOpt) ){
+    wctrlFlags &= ~WHERE_WANT_DISTINCT;
+  }
 
   /* The number of tables in the FROM clause is limited by the number of
   ** bits in a Bitmask 
@@ -108335,13 +110484,8 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   ** field (type Bitmask) it must be aligned on an 8-byte boundary on
   ** some architectures. Hence the ROUND8() below.
   */
-  db = pParse->db;
   nByteWInfo = ROUND8(sizeof(WhereInfo)+(nTabList-1)*sizeof(WhereLevel));
-  pWInfo = sqlite3DbMallocZero(db, 
-      nByteWInfo + 
-      sizeof(WhereClause) +
-      sizeof(WhereMaskSet)
-  );
+  pWInfo = sqlite3DbMallocZero(db, nByteWInfo + sizeof(WhereLoop));
   if( db->mallocFailed ){
     sqlite3DbFree(db, pWInfo);
     pWInfo = 0;
@@ -108350,23 +110494,29 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   pWInfo->nLevel = nTabList;
   pWInfo->pParse = pParse;
   pWInfo->pTabList = pTabList;
+  pWInfo->pOrderBy = pOrderBy;
+  pWInfo->pResultSet = pResultSet;
   pWInfo->iBreak = sqlite3VdbeMakeLabel(v);
-  pWInfo->pWC = pWC = (WhereClause *)&((u8 *)pWInfo)[nByteWInfo];
   pWInfo->wctrlFlags = wctrlFlags;
   pWInfo->savedNQueryLoop = pParse->nQueryLoop;
-  pMaskSet = (WhereMaskSet*)&pWC[1];
-
-  /* Disable the DISTINCT optimization if SQLITE_DistinctOpt is set via
-  ** sqlite3_test_ctrl(SQLITE_TESTCTRL_OPTIMIZATIONS,...) */
-  if( db->flags & SQLITE_DistinctOpt ) pDistinct = 0;
+  pMaskSet = &pWInfo->sMaskSet;
+  sWLB.pWInfo = pWInfo;
+  sWLB.pWC = &pWInfo->sWC;
+  sWLB.pNew = (WhereLoop*)(((char*)pWInfo)+nByteWInfo);
+  assert( EIGHT_BYTE_ALIGNMENT(sWLB.pNew) );
+  whereLoopInit(sWLB.pNew);
+#ifdef SQLITE_DEBUG
+  sWLB.pNew->cId = '*';
+#endif
 
   /* Split the WHERE clause into separate subexpressions where each
   ** subexpression is separated by an AND operator.
   */
   initMaskSet(pMaskSet);
-  whereClauseInit(pWC, pParse, pMaskSet, wctrlFlags);
+  whereClauseInit(&pWInfo->sWC, pWInfo);
   sqlite3ExprCodeConstants(pParse, pWhere);
-  whereSplit(pWC, pWhere, TK_AND);   /* IMP: R-15842-53296 */
+  whereSplit(&pWInfo->sWC, pWhere, TK_AND);
+  sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
     
   /* Special case: a WHERE clause that is constant.  Evaluate the
   ** expression and either jump over all of the code or fall thru.
@@ -108376,6 +110526,15 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     pWhere = 0;
   }
 
+  /* Special case: No FROM clause
+  */
+  if( nTabList==0 ){
+    if( pOrderBy ) pWInfo->bOBSat = 1;
+    if( wctrlFlags & WHERE_WANT_DISTINCT ){
+      pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
+    }
+  }
+
   /* Assign a bit from the bitmask to every term in the FROM clause.
   **
   ** When assigning bitmask values to FROM clause cursors, it must be
@@ -108387,30 +110546,19 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   ** bitmask for all tables to the left of the join.  Knowing the bitmask
   ** for all tables to the left of a left join is important.  Ticket #3015.
   **
-  ** Configure the WhereClause.vmask variable so that bits that correspond
-  ** to virtual table cursors are set. This is used to selectively disable 
-  ** the OR-to-IN transformation in exprAnalyzeOrTerm(). It is not helpful 
-  ** with virtual tables.
-  **
   ** Note that bitmasks are created for all pTabList->nSrc tables in
   ** pTabList, not just the first nTabList tables.  nTabList is normally
   ** equal to pTabList->nSrc but might be shortened to 1 if the
   ** WHERE_ONETABLE_ONLY flag is set.
   */
-  assert( pWC->vmask==0 && pMaskSet->n==0 );
-  for(i=0; i<pTabList->nSrc; i++){
-    createMask(pMaskSet, pTabList->a[i].iCursor);
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-    if( ALWAYS(pTabList->a[i].pTab) && IsVirtual(pTabList->a[i].pTab) ){
-      pWC->vmask |= ((Bitmask)1 << i);
-    }
-#endif
+  for(ii=0; ii<pTabList->nSrc; ii++){
+    createMask(pMaskSet, pTabList->a[ii].iCursor);
   }
 #ifndef NDEBUG
   {
     Bitmask toTheLeft = 0;
-    for(i=0; i<pTabList->nSrc; i++){
-      Bitmask m = getMask(pMaskSet, pTabList->a[i].iCursor);
+    for(ii=0; ii<pTabList->nSrc; ii++){
+      Bitmask m = getMask(pMaskSet, pTabList->a[ii].iCursor);
       assert( (m-1)==toTheLeft );
       toTheLeft |= m;
     }
@@ -108422,239 +110570,131 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   ** want to analyze these virtual terms, so start analyzing at the end
   ** and work forward so that the added virtual terms are never processed.
   */
-  exprAnalyzeAll(pTabList, pWC);
+  exprAnalyzeAll(pTabList, &pWInfo->sWC);
   if( db->mallocFailed ){
     goto whereBeginError;
   }
 
-  /* Check if the DISTINCT qualifier, if there is one, is redundant. 
-  ** If it is, then set pDistinct to NULL and WhereInfo.eDistinct to
-  ** WHERE_DISTINCT_UNIQUE to tell the caller to ignore the DISTINCT.
+  /* If the ORDER BY (or GROUP BY) clause contains references to general
+  ** expressions, then we won't be able to satisfy it using indices, so
+  ** go ahead and disable it now.
   */
-  if( pDistinct && isDistinctRedundant(pParse, pTabList, pWC, pDistinct) ){
-    pDistinct = 0;
-    pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
+  if( pOrderBy && (wctrlFlags & WHERE_WANT_DISTINCT)!=0 ){
+    for(ii=0; ii<pOrderBy->nExpr; ii++){
+      Expr *pExpr = sqlite3ExprSkipCollate(pOrderBy->a[ii].pExpr);
+      if( pExpr->op!=TK_COLUMN ){
+        pWInfo->pOrderBy = pOrderBy = 0;
+        break;
+      }else if( pExpr->iColumn<0 ){
+        break;
+      }
+    }
   }
 
-  /* Chose the best index to use for each table in the FROM clause.
-  **
-  ** This loop fills in the following fields:
-  **
-  **   pWInfo->a[].pIdx      The index to use for this level of the loop.
-  **   pWInfo->a[].wsFlags   WHERE_xxx flags associated with pIdx
-  **   pWInfo->a[].nEq       The number of == and IN constraints
-  **   pWInfo->a[].iFrom     Which term of the FROM clause is being coded
-  **   pWInfo->a[].iTabCur   The VDBE cursor for the database table
-  **   pWInfo->a[].iIdxCur   The VDBE cursor for the index
-  **   pWInfo->a[].pTerm     When wsFlags==WO_OR, the OR-clause term
-  **
-  ** This loop also figures out the nesting order of tables in the FROM
-  ** clause.
-  */
-  notReady = ~(Bitmask)0;
-  andFlags = ~0;
-  WHERETRACE(("*** Optimizer Start ***\n"));
-  for(i=iFrom=0, pLevel=pWInfo->a; i<nTabList; i++, pLevel++){
-    WhereCost bestPlan;         /* Most efficient plan seen so far */
-    Index *pIdx;                /* Index for FROM table at pTabItem */
-    int j;                      /* For looping over FROM tables */
-    int bestJ = -1;             /* The value of j */
-    Bitmask m;                  /* Bitmask value for j or bestJ */
-    int isOptimal;              /* Iterator for optimal/non-optimal search */
-    int nUnconstrained;         /* Number tables without INDEXED BY */
-    Bitmask notIndexed;         /* Mask of tables that cannot use an index */
+  if( wctrlFlags & WHERE_WANT_DISTINCT ){
+    if( isDistinctRedundant(pParse, pTabList, &pWInfo->sWC, pResultSet) ){
+      /* The DISTINCT marking is pointless.  Ignore it. */
+      pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
+    }else if( pOrderBy==0 ){
+      /* Try to ORDER BY the result set to make distinct processing easier */
+      pWInfo->wctrlFlags |= WHERE_DISTINCTBY;
+      pWInfo->pOrderBy = pResultSet;
+    }
+  }
 
-    memset(&bestPlan, 0, sizeof(bestPlan));
-    bestPlan.rCost = SQLITE_BIG_DBL;
-    WHERETRACE(("*** Begin search for loop %d ***\n", i));
-
-    /* Loop through the remaining entries in the FROM clause to find the
-    ** next nested loop. The loop tests all FROM clause entries
-    ** either once or twice. 
-    **
-    ** The first test is always performed if there are two or more entries
-    ** remaining and never performed if there is only one FROM clause entry
-    ** to choose from.  The first test looks for an "optimal" scan.  In
-    ** this context an optimal scan is one that uses the same strategy
-    ** for the given FROM clause entry as would be selected if the entry
-    ** were used as the innermost nested loop.  In other words, a table
-    ** is chosen such that the cost of running that table cannot be reduced
-    ** by waiting for other tables to run first.  This "optimal" test works
-    ** by first assuming that the FROM clause is on the inner loop and finding
-    ** its query plan, then checking to see if that query plan uses any
-    ** other FROM clause terms that are notReady.  If no notReady terms are
-    ** used then the "optimal" query plan works.
-    **
-    ** Note that the WhereCost.nRow parameter for an optimal scan might
-    ** not be as small as it would be if the table really were the innermost
-    ** join.  The nRow value can be reduced by WHERE clause constraints
-    ** that do not use indices.  But this nRow reduction only happens if the
-    ** table really is the innermost join.  
-    **
-    ** The second loop iteration is only performed if no optimal scan
-    ** strategies were found by the first iteration. This second iteration
-    ** is used to search for the lowest cost scan overall.
-    **
-    ** Previous versions of SQLite performed only the second iteration -
-    ** the next outermost loop was always that with the lowest overall
-    ** cost. However, this meant that SQLite could select the wrong plan
-    ** for scripts such as the following:
-    **   
-    **   CREATE TABLE t1(a, b); 
-    **   CREATE TABLE t2(c, d);
-    **   SELECT * FROM t2, t1 WHERE t2.rowid = t1.a;
-    **
-    ** The best strategy is to iterate through table t1 first. However it
-    ** is not possible to determine this with a simple greedy algorithm.
-    ** Since the cost of a linear scan through table t2 is the same 
-    ** as the cost of a linear scan through table t1, a simple greedy 
-    ** algorithm may choose to use t2 for the outer loop, which is a much
-    ** costlier approach.
-    */
-    nUnconstrained = 0;
-    notIndexed = 0;
-    for(isOptimal=(iFrom<nTabList-1); isOptimal>=0 && bestJ<0; isOptimal--){
-      Bitmask mask;             /* Mask of tables not yet ready */
-      for(j=iFrom, pTabItem=&pTabList->a[j]; j<nTabList; j++, pTabItem++){
-        int doNotReorder;    /* True if this table should not be reordered */
-        WhereCost sCost;     /* Cost information from best[Virtual]Index() */
-        ExprList *pOrderBy;  /* ORDER BY clause for index to optimize */
-        ExprList *pDist;     /* DISTINCT clause for index to optimize */
+  /* Construct the WhereLoop objects */
+  WHERETRACE(0xffff,("*** Optimizer Start ***\n"));
+  if( nTabList!=1 || whereShortCut(&sWLB)==0 ){
+    rc = whereLoopAddAll(&sWLB);
+    if( rc ) goto whereBeginError;
   
-        doNotReorder =  (pTabItem->jointype & (JT_LEFT|JT_CROSS))!=0;
-        if( j!=iFrom && doNotReorder ) break;
-        m = getMask(pMaskSet, pTabItem->iCursor);
-        if( (m & notReady)==0 ){
-          if( j==iFrom ) iFrom++;
-          continue;
-        }
-        mask = (isOptimal ? m : notReady);
-        pOrderBy = ((i==0 && ppOrderBy )?*ppOrderBy:0);
-        pDist = (i==0 ? pDistinct : 0);
-        if( pTabItem->pIndex==0 ) nUnconstrained++;
-  
-        WHERETRACE(("=== trying table %d with isOptimal=%d ===\n",
-                    j, isOptimal));
-        assert( pTabItem->pTab );
-#ifndef SQLITE_OMIT_VIRTUALTABLE
-        if( IsVirtual(pTabItem->pTab) ){
-          sqlite3_index_info **pp = &pWInfo->a[j].pIdxInfo;
-          bestVirtualIndex(pParse, pWC, pTabItem, mask, notReady, pOrderBy,
-                           &sCost, pp);
-        }else 
+    /* Display all of the WhereLoop objects if wheretrace is enabled */
+#ifdef WHERETRACE_ENABLED
+    if( sqlite3WhereTrace ){
+      WhereLoop *p;
+      int i;
+      static char zLabel[] = "0123456789abcdefghijklmnopqrstuvwyxz"
+                                       "ABCDEFGHIJKLMNOPQRSTUVWYXZ";
+      for(p=pWInfo->pLoops, i=0; p; p=p->pNextLoop, i++){
+        p->cId = zLabel[i%sizeof(zLabel)];
+        whereLoopPrint(p, pTabList);
+      }
+    }
 #endif
-        {
-          bestBtreeIndex(pParse, pWC, pTabItem, mask, notReady, pOrderBy,
-              pDist, &sCost);
-        }
-        assert( isOptimal || (sCost.used&notReady)==0 );
-
-        /* If an INDEXED BY clause is present, then the plan must use that
-        ** index if it uses any index at all */
-        assert( pTabItem->pIndex==0 
-                  || (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0
-                  || sCost.plan.u.pIdx==pTabItem->pIndex );
-
-        if( isOptimal && (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)==0 ){
-          notIndexed |= m;
-        }
-
-        /* Conditions under which this table becomes the best so far:
-        **
-        **   (1) The table must not depend on other tables that have not
-        **       yet run.
-        **
-        **   (2) A full-table-scan plan cannot supercede indexed plan unless
-        **       the full-table-scan is an "optimal" plan as defined above.
-        **
-        **   (3) All tables have an INDEXED BY clause or this table lacks an
-        **       INDEXED BY clause or this table uses the specific
-        **       index specified by its INDEXED BY clause.  This rule ensures
-        **       that a best-so-far is always selected even if an impossible
-        **       combination of INDEXED BY clauses are given.  The error
-        **       will be detected and relayed back to the application later.
-        **       The NEVER() comes about because rule (2) above prevents
-        **       An indexable full-table-scan from reaching rule (3).
-        **
-        **   (4) The plan cost must be lower than prior plans or else the
-        **       cost must be the same and the number of rows must be lower.
-        */
-        if( (sCost.used&notReady)==0                       /* (1) */
-            && (bestJ<0 || (notIndexed&m)!=0               /* (2) */
-                || (bestPlan.plan.wsFlags & WHERE_NOT_FULLSCAN)==0
-                || (sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0)
-            && (nUnconstrained==0 || pTabItem->pIndex==0   /* (3) */
-                || NEVER((sCost.plan.wsFlags & WHERE_NOT_FULLSCAN)!=0))
-            && (bestJ<0 || sCost.rCost<bestPlan.rCost      /* (4) */
-                || (sCost.rCost<=bestPlan.rCost 
-                 && sCost.plan.nRow<bestPlan.plan.nRow))
-        ){
-          WHERETRACE(("=== table %d is best so far"
-                      " with cost=%g and nRow=%g\n",
-                      j, sCost.rCost, sCost.plan.nRow));
-          bestPlan = sCost;
-          bestJ = j;
-        }
-        if( doNotReorder ) break;
-      }
-    }
-    assert( bestJ>=0 );
-    assert( notReady & getMask(pMaskSet, pTabList->a[bestJ].iCursor) );
-    WHERETRACE(("*** Optimizer selects table %d for loop %d"
-                " with cost=%g and nRow=%g\n",
-                bestJ, pLevel-pWInfo->a, bestPlan.rCost, bestPlan.plan.nRow));
-    /* The ALWAYS() that follows was added to hush up clang scan-build */
-    if( (bestPlan.plan.wsFlags & WHERE_ORDERBY)!=0 && ALWAYS(ppOrderBy) ){
-      *ppOrderBy = 0;
-    }
-    if( (bestPlan.plan.wsFlags & WHERE_DISTINCT)!=0 ){
-      assert( pWInfo->eDistinct==0 );
-      pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
-    }
-    andFlags &= bestPlan.plan.wsFlags;
-    pLevel->plan = bestPlan.plan;
-    testcase( bestPlan.plan.wsFlags & WHERE_INDEXED );
-    testcase( bestPlan.plan.wsFlags & WHERE_TEMP_INDEX );
-    if( bestPlan.plan.wsFlags & (WHERE_INDEXED|WHERE_TEMP_INDEX) ){
-      pLevel->iIdxCur = pParse->nTab++;
-    }else{
-      pLevel->iIdxCur = -1;
-    }
-    notReady &= ~getMask(pMaskSet, pTabList->a[bestJ].iCursor);
-    pLevel->iFrom = (u8)bestJ;
-    if( bestPlan.plan.nRow>=(double)1 ){
-      pParse->nQueryLoop *= bestPlan.plan.nRow;
-    }
-
-    /* Check that if the table scanned by this loop iteration had an
-    ** INDEXED BY clause attached to it, that the named index is being
-    ** used for the scan. If not, then query compilation has failed.
-    ** Return an error.
-    */
-    pIdx = pTabList->a[bestJ].pIndex;
-    if( pIdx ){
-      if( (bestPlan.plan.wsFlags & WHERE_INDEXED)==0 ){
-        sqlite3ErrorMsg(pParse, "cannot use index: %s", pIdx->zName);
-        goto whereBeginError;
-      }else{
-        /* If an INDEXED BY clause is used, the bestIndex() function is
-        ** guaranteed to find the index specified in the INDEXED BY clause
-        ** if it find an index at all. */
-        assert( bestPlan.plan.u.pIdx==pIdx );
-      }
+  
+    wherePathSolver(pWInfo, 0);
+    if( db->mallocFailed ) goto whereBeginError;
+    if( pWInfo->pOrderBy ){
+       wherePathSolver(pWInfo, pWInfo->nRowOut+1);
+       if( db->mallocFailed ) goto whereBeginError;
     }
   }
-  WHERETRACE(("*** Optimizer Finished ***\n"));
-  if( pParse->nErr || db->mallocFailed ){
+  if( pWInfo->pOrderBy==0 && (db->flags & SQLITE_ReverseOrder)!=0 ){
+     pWInfo->revMask = (Bitmask)(-1);
+  }
+  if( pParse->nErr || NEVER(db->mallocFailed) ){
     goto whereBeginError;
   }
-
-  /* If the total query only selects a single row, then the ORDER BY
-  ** clause is irrelevant.
-  */
-  if( (andFlags & WHERE_UNIQUE)!=0 && ppOrderBy ){
-    *ppOrderBy = 0;
+#ifdef WHERETRACE_ENABLED
+  if( sqlite3WhereTrace ){
+    int ii;
+    sqlite3DebugPrintf("---- Solution nRow=%d", pWInfo->nRowOut);
+    if( pWInfo->bOBSat ){
+      sqlite3DebugPrintf(" ORDERBY=0x%llx", pWInfo->revMask);
+    }
+    switch( pWInfo->eDistinct ){
+      case WHERE_DISTINCT_UNIQUE: {
+        sqlite3DebugPrintf("  DISTINCT=unique");
+        break;
+      }
+      case WHERE_DISTINCT_ORDERED: {
+        sqlite3DebugPrintf("  DISTINCT=ordered");
+        break;
+      }
+      case WHERE_DISTINCT_UNORDERED: {
+        sqlite3DebugPrintf("  DISTINCT=unordered");
+        break;
+      }
+    }
+    sqlite3DebugPrintf("\n");
+    for(ii=0; ii<pWInfo->nLevel; ii++){
+      whereLoopPrint(pWInfo->a[ii].pWLoop, pTabList);
+    }
   }
+#endif
+  /* Attempt to omit tables from the join that do not effect the result */
+  if( pWInfo->nLevel>=2
+   && pResultSet!=0
+   && OptimizationEnabled(db, SQLITE_OmitNoopJoin)
+  ){
+    Bitmask tabUsed = exprListTableUsage(pMaskSet, pResultSet);
+    if( sWLB.pOrderBy ) tabUsed |= exprListTableUsage(pMaskSet, sWLB.pOrderBy);
+    while( pWInfo->nLevel>=2 ){
+      WhereTerm *pTerm, *pEnd;
+      pLoop = pWInfo->a[pWInfo->nLevel-1].pWLoop;
+      if( (pWInfo->pTabList->a[pLoop->iTab].jointype & JT_LEFT)==0 ) break;
+      if( (wctrlFlags & WHERE_WANT_DISTINCT)==0
+       && (pLoop->wsFlags & WHERE_ONEROW)==0
+      ){
+        break;
+      }
+      if( (tabUsed & pLoop->maskSelf)!=0 ) break;
+      pEnd = sWLB.pWC->a + sWLB.pWC->nTerm;
+      for(pTerm=sWLB.pWC->a; pTerm<pEnd; pTerm++){
+        if( (pTerm->prereqAll & pLoop->maskSelf)!=0
+         && !ExprHasProperty(pTerm->pExpr, EP_FromJoin)
+        ){
+          break;
+        }
+      }
+      if( pTerm<pEnd ) break;
+      WHERETRACE(0xffff, ("-> drop loop %c not used\n", pLoop->cId));
+      pWInfo->nLevel--;
+      nTabList--;
+    }
+  }
+  WHERETRACE(0xffff,("*** Optimizer Finished ***\n"));
+  pWInfo->pParse->nQueryLoop += pWInfo->nRowOut;
 
   /* If the caller is an UPDATE or DELETE statement that is requesting
   ** to use a one-pass algorithm, determine if this is appropriate.
@@ -108662,42 +110702,43 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   ** the statement to update a single row.
   */
   assert( (wctrlFlags & WHERE_ONEPASS_DESIRED)==0 || pWInfo->nLevel==1 );
-  if( (wctrlFlags & WHERE_ONEPASS_DESIRED)!=0 && (andFlags & WHERE_UNIQUE)!=0 ){
+  if( (wctrlFlags & WHERE_ONEPASS_DESIRED)!=0 
+   && (pWInfo->a[0].pWLoop->wsFlags & WHERE_ONEROW)!=0 ){
     pWInfo->okOnePass = 1;
-    pWInfo->a[0].plan.wsFlags &= ~WHERE_IDX_ONLY;
+    pWInfo->a[0].pWLoop->wsFlags &= ~WHERE_IDX_ONLY;
   }
 
   /* Open all tables in the pTabList and any indices selected for
   ** searching those tables.
   */
-  sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
   notReady = ~(Bitmask)0;
-  pWInfo->nRowOut = (double)1;
-  for(i=0, pLevel=pWInfo->a; i<nTabList; i++, pLevel++){
+  for(ii=0, pLevel=pWInfo->a; ii<nTabList; ii++, pLevel++){
     Table *pTab;     /* Table to open */
     int iDb;         /* Index of database containing table/index */
+    struct SrcList_item *pTabItem;
 
     pTabItem = &pTabList->a[pLevel->iFrom];
     pTab = pTabItem->pTab;
-    pLevel->iTabCur = pTabItem->iCursor;
-    pWInfo->nRowOut *= pLevel->plan.nRow;
     iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
+    pLoop = pLevel->pWLoop;
     if( (pTab->tabFlags & TF_Ephemeral)!=0 || pTab->pSelect ){
       /* Do nothing */
     }else
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-    if( (pLevel->plan.wsFlags & WHERE_VIRTUALTABLE)!=0 ){
+    if( (pLoop->wsFlags & WHERE_VIRTUALTABLE)!=0 ){
       const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
       int iCur = pTabItem->iCursor;
       sqlite3VdbeAddOp4(v, OP_VOpen, iCur, 0, 0, pVTab, P4_VTAB);
+    }else if( IsVirtual(pTab) ){
+      /* noop */
     }else
 #endif
-    if( (pLevel->plan.wsFlags & WHERE_IDX_ONLY)==0
+    if( (pLoop->wsFlags & WHERE_IDX_ONLY)==0
          && (wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0 ){
       int op = pWInfo->okOnePass ? OP_OpenWrite : OP_OpenRead;
       sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, op);
-      testcase( pTab->nCol==BMS-1 );
-      testcase( pTab->nCol==BMS );
+      testcase( !pWInfo->okOnePass && pTab->nCol==BMS-1 );
+      testcase( !pWInfo->okOnePass && pTab->nCol==BMS );
       if( !pWInfo->okOnePass && pTab->nCol<BMS ){
         Bitmask b = pTabItem->colUsed;
         int n = 0;
@@ -108709,23 +110750,19 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
     }else{
       sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
     }
-#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
-    if( (pLevel->plan.wsFlags & WHERE_TEMP_INDEX)!=0 ){
-      constructAutomaticIndex(pParse, pWC, pTabItem, notReady, pLevel);
-    }else
-#endif
-    if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
-      Index *pIx = pLevel->plan.u.pIdx;
+    if( pLoop->wsFlags & WHERE_INDEXED ){
+      Index *pIx = pLoop->u.btree.pIndex;
       KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIx);
-      int iIdxCur = pLevel->iIdxCur;
+      /* FIXME:  As an optimization use pTabItem->iCursor if WHERE_IDX_ONLY */
+      int iIndexCur = pLevel->iIdxCur = iIdxCur ? iIdxCur : pParse->nTab++;
       assert( pIx->pSchema==pTab->pSchema );
-      assert( iIdxCur>=0 );
-      sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIx->tnum, iDb,
+      assert( iIndexCur>=0 );
+      sqlite3VdbeAddOp4(v, OP_OpenRead, iIndexCur, pIx->tnum, iDb,
                         (char*)pKey, P4_KEYINFO_HANDOFF);
       VdbeComment((v, "%s", pIx->zName));
     }
     sqlite3CodeVerifySchema(pParse, iDb);
-    notReady &= ~getMask(pWC->pMaskSet, pTabItem->iCursor);
+    notReady &= ~getMask(&pWInfo->sMaskSet, pTabItem->iCursor);
   }
   pWInfo->iTop = sqlite3VdbeCurrentAddr(v);
   if( db->mallocFailed ) goto whereBeginError;
@@ -108735,65 +110772,22 @@ SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
   ** program.
   */
   notReady = ~(Bitmask)0;
-  for(i=0; i<nTabList; i++){
-    pLevel = &pWInfo->a[i];
-    explainOneScan(pParse, pTabList, pLevel, i, pLevel->iFrom, wctrlFlags);
-    notReady = codeOneLoopStart(pWInfo, i, wctrlFlags, notReady);
+  for(ii=0; ii<nTabList; ii++){
+    pLevel = &pWInfo->a[ii];
+#ifndef SQLITE_OMIT_AUTOMATIC_INDEX
+    if( (pLevel->pWLoop->wsFlags & WHERE_AUTO_INDEX)!=0 ){
+      constructAutomaticIndex(pParse, &pWInfo->sWC,
+                &pTabList->a[pLevel->iFrom], notReady, pLevel);
+      if( db->mallocFailed ) goto whereBeginError;
+    }
+#endif
+    explainOneScan(pParse, pTabList, pLevel, ii, pLevel->iFrom, wctrlFlags);
+    pLevel->addrBody = sqlite3VdbeCurrentAddr(v);
+    notReady = codeOneLoopStart(pWInfo, ii, notReady);
     pWInfo->iContinue = pLevel->addrCont;
   }
 
-#ifdef SQLITE_TEST  /* For testing and debugging use only */
-  /* Record in the query plan information about the current table
-  ** and the index used to access it (if any).  If the table itself
-  ** is not used, its name is just '{}'.  If no index is used
-  ** the index is listed as "{}".  If the primary key is used the
-  ** index name is '*'.
-  */
-  for(i=0; i<nTabList; i++){
-    char *z;
-    int n;
-    pLevel = &pWInfo->a[i];
-    pTabItem = &pTabList->a[pLevel->iFrom];
-    z = pTabItem->zAlias;
-    if( z==0 ) z = pTabItem->pTab->zName;
-    n = sqlite3Strlen30(z);
-    if( n+nQPlan < sizeof(sqlite3_query_plan)-10 ){
-      if( pLevel->plan.wsFlags & WHERE_IDX_ONLY ){
-        memcpy(&sqlite3_query_plan[nQPlan], "{}", 2);
-        nQPlan += 2;
-      }else{
-        memcpy(&sqlite3_query_plan[nQPlan], z, n);
-        nQPlan += n;
-      }
-      sqlite3_query_plan[nQPlan++] = ' ';
-    }
-    testcase( pLevel->plan.wsFlags & WHERE_ROWID_EQ );
-    testcase( pLevel->plan.wsFlags & WHERE_ROWID_RANGE );
-    if( pLevel->plan.wsFlags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
-      memcpy(&sqlite3_query_plan[nQPlan], "* ", 2);
-      nQPlan += 2;
-    }else if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 ){
-      n = sqlite3Strlen30(pLevel->plan.u.pIdx->zName);
-      if( n+nQPlan < sizeof(sqlite3_query_plan)-2 ){
-        memcpy(&sqlite3_query_plan[nQPlan], pLevel->plan.u.pIdx->zName, n);
-        nQPlan += n;
-        sqlite3_query_plan[nQPlan++] = ' ';
-      }
-    }else{
-      memcpy(&sqlite3_query_plan[nQPlan], "{} ", 3);
-      nQPlan += 3;
-    }
-  }
-  while( nQPlan>0 && sqlite3_query_plan[nQPlan-1]==' ' ){
-    sqlite3_query_plan[--nQPlan] = 0;
-  }
-  sqlite3_query_plan[nQPlan] = 0;
-  nQPlan = 0;
-#endif /* SQLITE_TEST // Testing and debugging use only */
-
-  /* Record the continuation address in the WhereInfo structure.  Then
-  ** clean up and return.
-  */
+  /* Done. */
   return pWInfo;
 
   /* Jump here if malloc fails */
@@ -108814,6 +110808,7 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
   Vdbe *v = pParse->pVdbe;
   int i;
   WhereLevel *pLevel;
+  WhereLoop *pLoop;
   SrcList *pTabList = pWInfo->pTabList;
   sqlite3 *db = pParse->db;
 
@@ -108822,18 +110817,19 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
   sqlite3ExprCacheClear(pParse);
   for(i=pWInfo->nLevel-1; i>=0; i--){
     pLevel = &pWInfo->a[i];
+    pLoop = pLevel->pWLoop;
     sqlite3VdbeResolveLabel(v, pLevel->addrCont);
     if( pLevel->op!=OP_Noop ){
       sqlite3VdbeAddOp2(v, pLevel->op, pLevel->p1, pLevel->p2);
       sqlite3VdbeChangeP5(v, pLevel->p5);
     }
-    if( pLevel->plan.wsFlags & WHERE_IN_ABLE && pLevel->u.in.nIn>0 ){
+    if( pLoop->wsFlags & WHERE_IN_ABLE && pLevel->u.in.nIn>0 ){
       struct InLoop *pIn;
       int j;
       sqlite3VdbeResolveLabel(v, pLevel->addrNxt);
       for(j=pLevel->u.in.nIn, pIn=&pLevel->u.in.aInLoop[j-1]; j>0; j--, pIn--){
         sqlite3VdbeJumpHere(v, pIn->addrInTop+1);
-        sqlite3VdbeAddOp2(v, OP_Next, pIn->iCur, pIn->addrInTop);
+        sqlite3VdbeAddOp2(v, pIn->eEndLoopOp, pIn->iCur, pIn->addrInTop);
         sqlite3VdbeJumpHere(v, pIn->addrInTop-1);
       }
       sqlite3DbFree(db, pLevel->u.in.aInLoop);
@@ -108842,12 +110838,12 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
     if( pLevel->iLeftJoin ){
       int addr;
       addr = sqlite3VdbeAddOp1(v, OP_IfPos, pLevel->iLeftJoin);
-      assert( (pLevel->plan.wsFlags & WHERE_IDX_ONLY)==0
-           || (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 );
-      if( (pLevel->plan.wsFlags & WHERE_IDX_ONLY)==0 ){
+      assert( (pLoop->wsFlags & WHERE_IDX_ONLY)==0
+           || (pLoop->wsFlags & WHERE_INDEXED)!=0 );
+      if( (pLoop->wsFlags & WHERE_IDX_ONLY)==0 ){
         sqlite3VdbeAddOp1(v, OP_NullRow, pTabList->a[i].iCursor);
       }
-      if( pLevel->iIdxCur>=0 ){
+      if( pLoop->wsFlags & WHERE_INDEXED ){
         sqlite3VdbeAddOp1(v, OP_NullRow, pLevel->iIdxCur);
       }
       if( pLevel->op==OP_Return ){
@@ -108866,30 +110862,30 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
 
   /* Close all of the cursors that were opened by sqlite3WhereBegin.
   */
-  assert( pWInfo->nLevel==1 || pWInfo->nLevel==pTabList->nSrc );
+  assert( pWInfo->nLevel<=pTabList->nSrc );
   for(i=0, pLevel=pWInfo->a; i<pWInfo->nLevel; i++, pLevel++){
+    Index *pIdx = 0;
     struct SrcList_item *pTabItem = &pTabList->a[pLevel->iFrom];
     Table *pTab = pTabItem->pTab;
     assert( pTab!=0 );
+    pLoop = pLevel->pWLoop;
     if( (pTab->tabFlags & TF_Ephemeral)==0
      && pTab->pSelect==0
      && (pWInfo->wctrlFlags & WHERE_OMIT_OPEN_CLOSE)==0
     ){
-      int ws = pLevel->plan.wsFlags;
+      int ws = pLoop->wsFlags;
       if( !pWInfo->okOnePass && (ws & WHERE_IDX_ONLY)==0 ){
         sqlite3VdbeAddOp1(v, OP_Close, pTabItem->iCursor);
       }
-      if( (ws & WHERE_INDEXED)!=0 && (ws & WHERE_TEMP_INDEX)==0 ){
+      if( (ws & WHERE_INDEXED)!=0 && (ws & (WHERE_IPK|WHERE_AUTO_INDEX))==0 ){
         sqlite3VdbeAddOp1(v, OP_Close, pLevel->iIdxCur);
       }
     }
 
-    /* If this scan uses an index, make code substitutions to read data
-    ** from the index in preference to the table. Sometimes, this means
-    ** the table need never be read from. This is a performance boost,
-    ** as the vdbe level waits until the table is read before actually
-    ** seeking the table cursor to the record corresponding to the current
-    ** position in the index.
+    /* If this scan uses an index, make VDBE code substitutions to read data
+    ** from the index instead of from the table where possible.  In some cases
+    ** this optimization prevents the table from ever being read, which can
+    ** yield a significant performance boost.
     ** 
     ** Calls to the code generator in between sqlite3WhereBegin and
     ** sqlite3WhereEnd will have created code that references the table
@@ -108897,15 +110893,19 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
     ** that reference the table and converts them into opcodes that
     ** reference the index.
     */
-    if( (pLevel->plan.wsFlags & WHERE_INDEXED)!=0 && !db->mallocFailed){
+    if( pLoop->wsFlags & (WHERE_INDEXED|WHERE_IDX_ONLY) ){
+      pIdx = pLoop->u.btree.pIndex;
+    }else if( pLoop->wsFlags & WHERE_MULTI_OR ){
+      pIdx = pLevel->u.pCovidx;
+    }
+    if( pIdx && !db->mallocFailed ){
       int k, j, last;
       VdbeOp *pOp;
-      Index *pIdx = pLevel->plan.u.pIdx;
 
-      assert( pIdx!=0 );
-      pOp = sqlite3VdbeGetOp(v, pWInfo->iTop);
       last = sqlite3VdbeCurrentAddr(v);
-      for(k=pWInfo->iTop; k<last; k++, pOp++){
+      k = pLevel->addrBody;
+      pOp = sqlite3VdbeGetOp(v, k);
+      for(; k<last; k++, pOp++){
         if( pOp->p1!=pLevel->iTabCur ) continue;
         if( pOp->opcode==OP_Column ){
           for(j=0; j<pIdx->nColumn; j++){
@@ -108915,8 +110915,7 @@ SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
               break;
             }
           }
-          assert( (pLevel->plan.wsFlags & WHERE_IDX_ONLY)==0
-               || j<pIdx->nColumn );
+          assert( (pLoop->wsFlags & WHERE_IDX_ONLY)==0 || j<pIdx->nColumn );
         }else if( pOp->opcode==OP_Rowid ){
           pOp->p1 = pLevel->iIdxCur;
           pOp->opcode = OP_IdxRowid;
@@ -109137,6 +111136,7 @@ typedef union {
   IdList* yy180;
   struct {int value; int mask;} yy207;
   u8 yy258;
+  u16 yy305;
   struct LikeOp yy318;
   TriggerStep* yy327;
   ExprSpan yy342;
@@ -109153,7 +111153,7 @@ typedef union {
 #define sqlite3ParserARG_PDECL ,Parse *pParse
 #define sqlite3ParserARG_FETCH Parse *pParse = yypParser->pParse
 #define sqlite3ParserARG_STORE yypParser->pParse = pParse
-#define YYNSTATE 627
+#define YYNSTATE 628
 #define YYNRULE 327
 #define YYFALLBACK 1
 #define YY_NO_ACTION      (YYNSTATE+YYNRULE+2)
@@ -109226,163 +111226,163 @@ static const YYMINORTYPE yyzerominor = { 0 };
 */
 #define YY_ACTTAB_COUNT (1564)
 static const YYACTIONTYPE yy_action[] = {
- /*     0 */   309,  955,  184,  417,    2,  171,  624,  594,   56,   56,
+ /*     0 */   310,  956,  184,  418,    2,  171,  625,  595,   56,   56,
  /*    10 */    56,   56,   49,   54,   54,   54,   54,   53,   53,   52,
- /*    20 */    52,   52,   51,  233,  620,  619,  298,  620,  619,  234,
- /*    30 */   587,  581,   56,   56,   56,   56,   19,   54,   54,   54,
- /*    40 */    54,   53,   53,   52,   52,   52,   51,  233,  605,   57,
- /*    50 */    58,   48,  579,  578,  580,  580,   55,   55,   56,   56,
- /*    60 */    56,   56,  541,   54,   54,   54,   54,   53,   53,   52,
- /*    70 */    52,   52,   51,  233,  309,  594,  325,  196,  195,  194,
+ /*    20 */    52,   52,   51,  233,  621,  620,  299,  621,  620,  234,
+ /*    30 */   588,  582,   56,   56,   56,   56,   19,   54,   54,   54,
+ /*    40 */    54,   53,   53,   52,   52,   52,   51,  233,  606,   57,
+ /*    50 */    58,   48,  580,  579,  581,  581,   55,   55,   56,   56,
+ /*    60 */    56,   56,  542,   54,   54,   54,   54,   53,   53,   52,
+ /*    70 */    52,   52,   51,  233,  310,  595,  326,  196,  195,  194,
  /*    80 */    33,   54,   54,   54,   54,   53,   53,   52,   52,   52,
- /*    90 */    51,  233,  617,  616,  165,  617,  616,  380,  377,  376,
- /*   100 */   407,  532,  576,  576,  587,  581,  303,  422,  375,   59,
+ /*    90 */    51,  233,  618,  617,  165,  618,  617,  381,  378,  377,
+ /*   100 */   408,  533,  577,  577,  588,  582,  304,  423,  376,   59,
  /*   110 */    53,   53,   52,   52,   52,   51,  233,   50,   47,  146,
- /*   120 */   574,  545,   65,   57,   58,   48,  579,  578,  580,  580,
+ /*   120 */   575,  546,   65,   57,   58,   48,  580,  579,  581,  581,
  /*   130 */    55,   55,   56,   56,   56,   56,  213,   54,   54,   54,
- /*   140 */    54,   53,   53,   52,   52,   52,   51,  233,  309,  223,
- /*   150 */   539,  420,  170,  176,  138,  280,  383,  275,  382,  168,
- /*   160 */   489,  551,  409,  668,  620,  619,  271,  438,  409,  438,
- /*   170 */   550,  604,   67,  482,  507,  618,  599,  412,  587,  581,
- /*   180 */   600,  483,  618,  412,  618,  598,   91,  439,  440,  439,
- /*   190 */   335,  598,   73,  669,  222,  266,  480,   57,   58,   48,
- /*   200 */   579,  578,  580,  580,   55,   55,   56,   56,   56,   56,
- /*   210 */   670,   54,   54,   54,   54,   53,   53,   52,   52,   52,
- /*   220 */    51,  233,  309,  279,  232,  231,    1,  132,  200,  385,
- /*   230 */   620,  619,  617,  616,  278,  435,  289,  563,  175,  262,
- /*   240 */   409,  264,  437,  497,  436,  166,  441,  568,  336,  568,
- /*   250 */   201,  537,  587,  581,  599,  412,  165,  594,  600,  380,
- /*   260 */   377,  376,  597,  598,   92,  523,  618,  569,  569,  592,
- /*   270 */   375,   57,   58,   48,  579,  578,  580,  580,   55,   55,
- /*   280 */    56,   56,   56,   56,  597,   54,   54,   54,   54,   53,
- /*   290 */    53,   52,   52,   52,   51,  233,  309,  463,  617,  616,
- /*   300 */   590,  590,  590,  174,  272,  396,  409,  272,  409,  548,
- /*   310 */   397,  620,  619,   68,  326,  620,  619,  620,  619,  618,
- /*   320 */   546,  412,  618,  412,  471,  594,  587,  581,  472,  598,
- /*   330 */    92,  598,   92,   52,   52,   52,   51,  233,  513,  512,
- /*   340 */   206,  322,  363,  464,  221,   57,   58,   48,  579,  578,
- /*   350 */   580,  580,   55,   55,   56,   56,   56,   56,  529,   54,
+ /*   140 */    54,   53,   53,   52,   52,   52,   51,  233,  310,  223,
+ /*   150 */   540,  421,  170,  176,  138,  281,  384,  276,  383,  168,
+ /*   160 */   490,  552,  410,  669,  621,  620,  272,  439,  410,  439,
+ /*   170 */   551,  605,   67,  483,  508,  619,  600,  413,  588,  582,
+ /*   180 */   601,  484,  619,  413,  619,  599,   91,  440,  441,  440,
+ /*   190 */   336,  599,   73,  670,  222,  267,  481,   57,   58,   48,
+ /*   200 */   580,  579,  581,  581,   55,   55,   56,   56,   56,   56,
+ /*   210 */   671,   54,   54,   54,   54,   53,   53,   52,   52,   52,
+ /*   220 */    51,  233,  310,  280,  232,  231,    1,  132,  200,  386,
+ /*   230 */   621,  620,  618,  617,  279,  436,  290,  564,  175,  263,
+ /*   240 */   410,  265,  438,  498,  437,  166,  442,  569,  337,  569,
+ /*   250 */   201,  538,  588,  582,  600,  413,  165,  595,  601,  381,
+ /*   260 */   378,  377,  598,  599,   92,  524,  619,  570,  570,  593,
+ /*   270 */   376,   57,   58,   48,  580,  579,  581,  581,   55,   55,
+ /*   280 */    56,   56,   56,   56,  598,   54,   54,   54,   54,   53,
+ /*   290 */    53,   52,   52,   52,   51,  233,  310,  464,  618,  617,
+ /*   300 */   591,  591,  591,  174,  273,  397,  410,  273,  410,  549,
+ /*   310 */   398,  621,  620,   68,  327,  621,  620,  621,  620,  619,
+ /*   320 */   547,  413,  619,  413,  472,  595,  588,  582,  473,  599,
+ /*   330 */    92,  599,   92,   52,   52,   52,   51,  233,  514,  513,
+ /*   340 */   206,  323,  364,  465,  221,   57,   58,   48,  580,  579,
+ /*   350 */   581,  581,   55,   55,   56,   56,   56,   56,  530,   54,
  /*   360 */    54,   54,   54,   53,   53,   52,   52,   52,   51,  233,
- /*   370 */   309,  396,  409,  396,  597,  372,  386,  530,  347,  617,
- /*   380 */   616,  575,  202,  617,  616,  617,  616,  412,  620,  619,
- /*   390 */   145,  255,  346,  254,  577,  598,   74,  351,   45,  489,
- /*   400 */   587,  581,  235,  189,  464,  544,  167,  296,  187,  469,
- /*   410 */   479,   67,   62,   39,  618,  546,  597,  345,  573,   57,
- /*   420 */    58,   48,  579,  578,  580,  580,   55,   55,   56,   56,
+ /*   370 */   310,  397,  410,  397,  598,  373,  387,  531,  348,  618,
+ /*   380 */   617,  576,  202,  618,  617,  618,  617,  413,  621,  620,
+ /*   390 */   145,  255,  347,  254,  578,  599,   74,  352,   45,  490,
+ /*   400 */   588,  582,  235,  189,  465,  545,  167,  297,  187,  470,
+ /*   410 */   480,   67,   62,   39,  619,  547,  598,  346,  574,   57,
+ /*   420 */    58,   48,  580,  579,  581,  581,   55,   55,   56,   56,
  /*   430 */    56,   56,    6,   54,   54,   54,   54,   53,   53,   52,
- /*   440 */    52,   52,   51,  233,  309,  562,  558,  407,  528,  576,
- /*   450 */   576,  344,  255,  346,  254,  182,  617,  616,  503,  504,
- /*   460 */   314,  409,  557,  235,  166,  271,  409,  352,  564,  181,
- /*   470 */   407,  546,  576,  576,  587,  581,  412,  537,  556,  561,
- /*   480 */   517,  412,  618,  249,  598,   16,    7,   36,  467,  598,
- /*   490 */    92,  516,  618,   57,   58,   48,  579,  578,  580,  580,
- /*   500 */    55,   55,   56,   56,   56,   56,  541,   54,   54,   54,
- /*   510 */    54,   53,   53,   52,   52,   52,   51,  233,  309,  327,
- /*   520 */   572,  571,  525,  558,  560,  394,  871,  246,  409,  248,
- /*   530 */   171,  392,  594,  219,  407,  409,  576,  576,  502,  557,
- /*   540 */   364,  145,  510,  412,  407,  229,  576,  576,  587,  581,
- /*   550 */   412,  598,   92,  381,  269,  556,  166,  400,  598,   69,
- /*   560 */   501,  419,  945,  199,  945,  198,  546,   57,   58,   48,
- /*   570 */   579,  578,  580,  580,   55,   55,   56,   56,   56,   56,
- /*   580 */   568,   54,   54,   54,   54,   53,   53,   52,   52,   52,
- /*   590 */    51,  233,  309,  317,  419,  944,  508,  944,  308,  597,
- /*   600 */   594,  565,  490,  212,  173,  247,  423,  615,  614,  613,
- /*   610 */   323,  197,  143,  405,  572,  571,  489,   66,   50,   47,
- /*   620 */   146,  594,  587,  581,  232,  231,  559,  427,   67,  555,
- /*   630 */    15,  618,  186,  543,  303,  421,   35,  206,  432,  423,
- /*   640 */   552,   57,   58,   48,  579,  578,  580,  580,   55,   55,
+ /*   440 */    52,   52,   51,  233,  310,  563,  559,  408,  529,  577,
+ /*   450 */   577,  345,  255,  347,  254,  182,  618,  617,  504,  505,
+ /*   460 */   315,  410,  558,  235,  166,  272,  410,  353,  565,  181,
+ /*   470 */   408,  547,  577,  577,  588,  582,  413,  538,  557,  562,
+ /*   480 */   518,  413,  619,  249,  599,   16,    7,   36,  468,  599,
+ /*   490 */    92,  517,  619,   57,   58,   48,  580,  579,  581,  581,
+ /*   500 */    55,   55,   56,   56,   56,   56,  542,   54,   54,   54,
+ /*   510 */    54,   53,   53,   52,   52,   52,   51,  233,  310,  328,
+ /*   520 */   573,  572,  526,  559,  561,  395,  872,  246,  410,  248,
+ /*   530 */   171,  393,  595,  219,  408,  410,  577,  577,  503,  558,
+ /*   540 */   365,  145,  511,  413,  408,  229,  577,  577,  588,  582,
+ /*   550 */   413,  599,   92,  382,  270,  557,  166,  401,  599,   69,
+ /*   560 */   502,  420,  946,  199,  946,  198,  547,   57,   58,   48,
+ /*   570 */   580,  579,  581,  581,   55,   55,   56,   56,   56,   56,
+ /*   580 */   569,   54,   54,   54,   54,   53,   53,   52,   52,   52,
+ /*   590 */    51,  233,  310,  318,  420,  945,  509,  945,  309,  598,
+ /*   600 */   595,  566,  491,  212,  173,  247,  424,  616,  615,  614,
+ /*   610 */   324,  197,  143,  406,  573,  572,  490,   66,   50,   47,
+ /*   620 */   146,  595,  588,  582,  232,  231,  560,  428,   67,  556,
+ /*   630 */    15,  619,  186,  544,  304,  422,   35,  206,  433,  424,
+ /*   640 */   553,   57,   58,   48,  580,  579,  581,  581,   55,   55,
  /*   650 */    56,   56,   56,   56,  205,   54,   54,   54,   54,   53,
- /*   660 */    53,   52,   52,   52,   51,  233,  309,  569,  569,  260,
- /*   670 */   268,  597,   12,  373,  568,  166,  409,  313,  409,  420,
- /*   680 */   409,  473,  473,  365,  618,   50,   47,  146,  597,  594,
- /*   690 */   468,  412,  166,  412,  351,  412,  587,  581,   32,  598,
- /*   700 */    94,  598,   97,  598,   95,  627,  625,  329,  142,   50,
- /*   710 */    47,  146,  333,  349,  358,   57,   58,   48,  579,  578,
- /*   720 */   580,  580,   55,   55,   56,   56,   56,   56,  409,   54,
+ /*   660 */    53,   52,   52,   52,   51,  233,  310,  570,  570,  261,
+ /*   670 */   269,  598,   12,  374,  569,  166,  410,  314,  410,  421,
+ /*   680 */   410,  474,  474,  366,  619,   50,   47,  146,  598,  595,
+ /*   690 */   256,  413,  166,  413,  352,  413,  588,  582,   32,  599,
+ /*   700 */    94,  599,   97,  599,   95,  628,  626,  330,  142,   50,
+ /*   710 */    47,  146,  334,  350,  359,   57,   58,   48,  580,  579,
+ /*   720 */   581,  581,   55,   55,   56,   56,   56,   56,  410,   54,
  /*   730 */    54,   54,   54,   53,   53,   52,   52,   52,   51,  233,
- /*   740 */   309,  409,  388,  412,  409,   22,  565,  404,  212,  362,
- /*   750 */   389,  598,  104,  359,  409,  156,  412,  409,  603,  412,
- /*   760 */   537,  331,  569,  569,  598,  103,  493,  598,  105,  412,
- /*   770 */   587,  581,  412,  260,  549,  618,   11,  598,  106,  521,
- /*   780 */   598,  133,  169,  457,  456,  170,   35,  601,  618,   57,
- /*   790 */    58,   48,  579,  578,  580,  580,   55,   55,   56,   56,
- /*   800 */    56,   56,  409,   54,   54,   54,   54,   53,   53,   52,
- /*   810 */    52,   52,   51,  233,  309,  409,  259,  412,  409,   50,
- /*   820 */    47,  146,  357,  318,  355,  598,  134,  527,  352,  337,
- /*   830 */   412,  409,  356,  412,  357,  409,  357,  618,  598,   98,
- /*   840 */   129,  598,  102,  618,  587,  581,  412,   21,  235,  618,
- /*   850 */   412,  618,  211,  143,  598,  101,   30,  167,  598,   93,
- /*   860 */   350,  535,  203,   57,   58,   48,  579,  578,  580,  580,
- /*   870 */    55,   55,   56,   56,   56,   56,  409,   54,   54,   54,
- /*   880 */    54,   53,   53,   52,   52,   52,   51,  233,  309,  409,
- /*   890 */   526,  412,  409,  425,  215,  305,  597,  551,  141,  598,
- /*   900 */   100,   40,  409,   38,  412,  409,  550,  412,  409,  228,
- /*   910 */   220,  314,  598,   77,  500,  598,   96,  412,  587,  581,
- /*   920 */   412,  338,  253,  412,  218,  598,  137,  379,  598,  136,
- /*   930 */    28,  598,  135,  270,  715,  210,  481,   57,   58,   48,
- /*   940 */   579,  578,  580,  580,   55,   55,   56,   56,   56,   56,
- /*   950 */   409,   54,   54,   54,   54,   53,   53,   52,   52,   52,
- /*   960 */    51,  233,  309,  409,  272,  412,  409,  315,  147,  597,
- /*   970 */   272,  626,    2,  598,   76,  209,  409,  127,  412,  618,
- /*   980 */   126,  412,  409,  621,  235,  618,  598,   90,  374,  598,
- /*   990 */    89,  412,  587,  581,   27,  260,  350,  412,  618,  598,
- /*  1000 */    75,  321,  541,  541,  125,  598,   88,  320,  278,  597,
- /*  1010 */   618,   57,   46,   48,  579,  578,  580,  580,   55,   55,
- /*  1020 */    56,   56,   56,   56,  409,   54,   54,   54,   54,   53,
- /*  1030 */    53,   52,   52,   52,   51,  233,  309,  409,  450,  412,
- /*  1040 */   164,  284,  282,  272,  609,  424,  304,  598,   87,  370,
- /*  1050 */   409,  477,  412,  409,  608,  409,  607,  602,  618,  618,
- /*  1060 */   598,   99,  586,  585,  122,  412,  587,  581,  412,  618,
- /*  1070 */   412,  618,  618,  598,   86,  366,  598,   17,  598,   85,
- /*  1080 */   319,  185,  519,  518,  583,  582,   58,   48,  579,  578,
- /*  1090 */   580,  580,   55,   55,   56,   56,   56,   56,  409,   54,
+ /*   740 */   310,  410,  389,  413,  410,   22,  566,  405,  212,  363,
+ /*   750 */   390,  599,  104,  360,  410,  156,  413,  410,  604,  413,
+ /*   760 */   538,  332,  570,  570,  599,  103,  494,  599,  105,  413,
+ /*   770 */   588,  582,  413,  261,  550,  619,   11,  599,  106,  522,
+ /*   780 */   599,  133,  169,  458,  457,  170,   35,  602,  619,   57,
+ /*   790 */    58,   48,  580,  579,  581,  581,   55,   55,   56,   56,
+ /*   800 */    56,   56,  410,   54,   54,   54,   54,   53,   53,   52,
+ /*   810 */    52,   52,   51,  233,  310,  410,  260,  413,  410,   50,
+ /*   820 */    47,  146,  358,  319,  356,  599,  134,  528,  353,  338,
+ /*   830 */   413,  410,  357,  413,  358,  410,  358,  619,  599,   98,
+ /*   840 */   129,  599,  102,  619,  588,  582,  413,   21,  235,  619,
+ /*   850 */   413,  619,  211,  143,  599,  101,   30,  167,  599,   93,
+ /*   860 */   351,  536,  203,   57,   58,   48,  580,  579,  581,  581,
+ /*   870 */    55,   55,   56,   56,   56,   56,  410,   54,   54,   54,
+ /*   880 */    54,   53,   53,   52,   52,   52,   51,  233,  310,  410,
+ /*   890 */   527,  413,  410,  426,  215,  306,  598,  552,  141,  599,
+ /*   900 */   100,   40,  410,   38,  413,  410,  551,  413,  410,  228,
+ /*   910 */   220,  315,  599,   77,  501,  599,   96,  413,  588,  582,
+ /*   920 */   413,  339,  253,  413,  218,  599,  137,  380,  599,  136,
+ /*   930 */    28,  599,  135,  271,  716,  210,  482,   57,   58,   48,
+ /*   940 */   580,  579,  581,  581,   55,   55,   56,   56,   56,   56,
+ /*   950 */   410,   54,   54,   54,   54,   53,   53,   52,   52,   52,
+ /*   960 */    51,  233,  310,  410,  273,  413,  410,  316,  147,  598,
+ /*   970 */   273,  627,    2,  599,   76,  209,  410,  127,  413,  619,
+ /*   980 */   126,  413,  410,  622,  235,  619,  599,   90,  375,  599,
+ /*   990 */    89,  413,  588,  582,   27,  261,  351,  413,  619,  599,
+ /*  1000 */    75,  322,  542,  542,  125,  599,   88,  321,  279,  598,
+ /*  1010 */   619,   57,   46,   48,  580,  579,  581,  581,   55,   55,
+ /*  1020 */    56,   56,   56,   56,  410,   54,   54,   54,   54,   53,
+ /*  1030 */    53,   52,   52,   52,   51,  233,  310,  410,  451,  413,
+ /*  1040 */   164,  285,  283,  273,  610,  425,  305,  599,   87,  371,
+ /*  1050 */   410,  478,  413,  410,  609,  410,  608,  603,  619,  619,
+ /*  1060 */   599,   99,  587,  586,  122,  413,  588,  582,  413,  619,
+ /*  1070 */   413,  619,  619,  599,   86,  367,  599,   17,  599,   85,
+ /*  1080 */   320,  185,  520,  519,  584,  583,   58,   48,  580,  579,
+ /*  1090 */   581,  581,   55,   55,   56,   56,   56,   56,  410,   54,
  /*  1100 */    54,   54,   54,   53,   53,   52,   52,   52,   51,  233,
- /*  1110 */   309,  584,  409,  412,  409,  260,  260,  260,  408,  591,
- /*  1120 */   474,  598,   84,  170,  409,  466,  518,  412,  121,  412,
- /*  1130 */   618,  618,  618,  618,  618,  598,   83,  598,   72,  412,
- /*  1140 */   587,  581,   51,  233,  625,  329,  470,  598,   71,  257,
- /*  1150 */   159,  120,   14,  462,  157,  158,  117,  260,  448,  447,
- /*  1160 */   446,   48,  579,  578,  580,  580,   55,   55,   56,   56,
- /*  1170 */    56,   56,  618,   54,   54,   54,   54,   53,   53,   52,
- /*  1180 */    52,   52,   51,  233,   44,  403,  260,    3,  409,  459,
- /*  1190 */   260,  413,  619,  118,  398,   10,   25,   24,  554,  348,
- /*  1200 */   217,  618,  406,  412,  409,  618,    4,   44,  403,  618,
- /*  1210 */     3,  598,   82,  618,  413,  619,  455,  542,  115,  412,
- /*  1220 */   538,  401,  536,  274,  506,  406,  251,  598,   81,  216,
- /*  1230 */   273,  563,  618,  243,  453,  618,  154,  618,  618,  618,
- /*  1240 */   449,  416,  623,  110,  401,  618,  409,  236,   64,  123,
- /*  1250 */   487,   41,   42,  531,  563,  204,  409,  267,   43,  411,
- /*  1260 */   410,  412,  265,  592,  108,  618,  107,  434,  332,  598,
- /*  1270 */    80,  412,  618,  263,   41,   42,  443,  618,  409,  598,
- /*  1280 */    70,   43,  411,  410,  433,  261,  592,  149,  618,  597,
- /*  1290 */   256,  237,  188,  412,  590,  590,  590,  589,  588,   13,
- /*  1300 */   618,  598,   18,  328,  235,  618,   44,  403,  360,    3,
- /*  1310 */   418,  461,  339,  413,  619,  227,  124,  590,  590,  590,
- /*  1320 */   589,  588,   13,  618,  406,  409,  618,  409,  139,   34,
- /*  1330 */   403,  387,    3,  148,  622,  312,  413,  619,  311,  330,
- /*  1340 */   412,  460,  412,  401,  180,  353,  412,  406,  598,   79,
- /*  1350 */   598,   78,  250,  563,  598,    9,  618,  612,  611,  610,
- /*  1360 */   618,    8,  452,  442,  242,  415,  401,  618,  239,  235,
- /*  1370 */   179,  238,  428,   41,   42,  288,  563,  618,  618,  618,
- /*  1380 */    43,  411,  410,  618,  144,  592,  618,  618,  177,   61,
- /*  1390 */   618,  596,  391,  620,  619,  287,   41,   42,  414,  618,
- /*  1400 */   293,   30,  393,   43,  411,  410,  292,  618,  592,   31,
- /*  1410 */   618,  395,  291,   60,  230,   37,  590,  590,  590,  589,
- /*  1420 */   588,   13,  214,  553,  183,  290,  172,  301,  300,  299,
- /*  1430 */   178,  297,  595,  563,  451,   29,  285,  390,  540,  590,
- /*  1440 */   590,  590,  589,  588,   13,  283,  520,  534,  150,  533,
- /*  1450 */   241,  281,  384,  192,  191,  324,  515,  514,  276,  240,
- /*  1460 */   510,  523,  307,  511,  128,  592,  509,  225,  226,  486,
- /*  1470 */   485,  224,  152,  491,  464,  306,  484,  163,  153,  371,
- /*  1480 */   478,  151,  162,  258,  369,  161,  367,  208,  475,  476,
- /*  1490 */    26,  160,  465,  140,  361,  131,  590,  590,  590,  116,
- /*  1500 */   119,  454,  343,  155,  114,  342,  113,  112,  445,  111,
- /*  1510 */   130,  109,  431,  316,  426,  430,   23,  429,   20,  606,
- /*  1520 */   190,  507,  255,  341,  244,   63,  294,  593,  310,  570,
- /*  1530 */   277,  402,  354,  235,  567,  496,  495,  492,  494,  302,
- /*  1540 */   458,  378,  286,  245,  566,    5,  252,  547,  193,  444,
- /*  1550 */   233,  340,  207,  524,  368,  505,  334,  522,  499,  399,
- /*  1560 */   295,  498,  956,  488,
+ /*  1110 */   310,  585,  410,  413,  410,  261,  261,  261,  409,  592,
+ /*  1120 */   475,  599,   84,  170,  410,  467,  519,  413,  121,  413,
+ /*  1130 */   619,  619,  619,  619,  619,  599,   83,  599,   72,  413,
+ /*  1140 */   588,  582,   51,  233,  626,  330,  471,  599,   71,  258,
+ /*  1150 */   159,  120,   14,  463,  157,  158,  117,  261,  449,  448,
+ /*  1160 */   447,   48,  580,  579,  581,  581,   55,   55,   56,   56,
+ /*  1170 */    56,   56,  619,   54,   54,   54,   54,   53,   53,   52,
+ /*  1180 */    52,   52,   51,  233,   44,  404,  261,    3,  410,  460,
+ /*  1190 */   261,  414,  620,  118,  399,   10,   25,   24,  555,  349,
+ /*  1200 */   217,  619,  407,  413,  410,  619,    4,   44,  404,  619,
+ /*  1210 */     3,  599,   82,  619,  414,  620,  456,  543,  115,  413,
+ /*  1220 */   539,  402,  537,  275,  507,  407,  251,  599,   81,  216,
+ /*  1230 */   274,  564,  619,  243,  454,  619,  154,  619,  619,  619,
+ /*  1240 */   450,  417,  624,  110,  402,  619,  410,  236,   64,  123,
+ /*  1250 */   488,   41,   42,  532,  564,  204,  410,  268,   43,  412,
+ /*  1260 */   411,  413,  266,  593,  108,  619,  107,  435,  333,  599,
+ /*  1270 */    80,  413,  619,  264,   41,   42,  444,  619,  410,  599,
+ /*  1280 */    70,   43,  412,  411,  434,  262,  593,  149,  619,  598,
+ /*  1290 */   257,  237,  188,  413,  591,  591,  591,  590,  589,   13,
+ /*  1300 */   619,  599,   18,  329,  235,  619,   44,  404,  361,    3,
+ /*  1310 */   419,  462,  340,  414,  620,  227,  124,  591,  591,  591,
+ /*  1320 */   590,  589,   13,  619,  407,  410,  619,  410,  139,   34,
+ /*  1330 */   404,  388,    3,  148,  623,  313,  414,  620,  312,  331,
+ /*  1340 */   413,  461,  413,  402,  180,  354,  413,  407,  599,   79,
+ /*  1350 */   599,   78,  250,  564,  599,    9,  619,  613,  612,  611,
+ /*  1360 */   619,    8,  453,  443,  242,  416,  402,  619,  239,  235,
+ /*  1370 */   179,  238,  429,   41,   42,  289,  564,  619,  619,  619,
+ /*  1380 */    43,  412,  411,  619,  144,  593,  619,  619,  177,   61,
+ /*  1390 */   619,  597,  392,  621,  620,  288,   41,   42,  415,  619,
+ /*  1400 */   294,   30,  394,   43,  412,  411,  293,  619,  593,   31,
+ /*  1410 */   619,  396,  292,   60,  230,   37,  591,  591,  591,  590,
+ /*  1420 */   589,   13,  214,  554,  183,  291,  172,  302,  301,  300,
+ /*  1430 */   178,  298,  596,  564,  452,   29,  286,  391,  541,  591,
+ /*  1440 */   591,  591,  590,  589,   13,  284,  521,  535,  150,  534,
+ /*  1450 */   241,  282,  385,  192,  191,  325,  516,  515,  277,  240,
+ /*  1460 */   511,  524,  308,  512,  128,  593,  510,  225,  226,  487,
+ /*  1470 */   486,  224,  152,  492,  465,  307,  485,  163,  153,  372,
+ /*  1480 */   479,  151,  162,  259,  370,  161,  368,  208,  476,  477,
+ /*  1490 */    26,  160,  469,  466,  362,  140,  591,  591,  591,  116,
+ /*  1500 */   119,  455,  344,  155,  114,  343,  113,  112,  446,  111,
+ /*  1510 */   131,  109,  432,  317,  130,  431,   23,   20,  430,  427,
+ /*  1520 */   190,   63,  255,  342,  244,  607,  295,  287,  311,  594,
+ /*  1530 */   278,  508,  496,  235,  493,  571,  497,  568,  495,  403,
+ /*  1540 */   459,  379,  355,  245,  193,  303,  567,  296,  341,    5,
+ /*  1550 */   445,  548,  506,  207,  525,  500,  335,  489,  252,  369,
+ /*  1560 */   400,  499,  523,  233,
 };
 static const YYCODETYPE yy_lookahead[] = {
  /*     0 */    19,  142,  143,  144,  145,   24,    1,   26,   77,   78,
@@ -109534,17 +111534,17 @@ static const YYCODETYPE yy_lookahead[] = {
  /*  1460 */   103,   94,  178,  177,   22,   98,  175,   92,  228,  175,
  /*  1470 */   175,  228,   55,  183,   57,  178,  175,  156,   61,   18,
  /*  1480 */   157,   64,  156,  235,  157,  156,   45,  157,  236,  157,
- /*  1490 */   135,  156,  189,   68,  157,  218,  129,  130,  131,   22,
+ /*  1490 */   135,  156,  199,  189,  157,   68,  129,  130,  131,   22,
  /*  1500 */   189,  199,  157,  156,  192,   18,  192,  192,  199,  192,
- /*  1510 */   218,  189,   40,  157,   38,  157,  240,  157,  240,  153,
- /*  1520 */   196,  181,  105,  106,  107,  243,  198,  166,  111,  230,
- /*  1530 */   176,  226,  239,  116,  230,  176,  166,  166,  176,  148,
- /*  1540 */   199,  177,  209,  209,  166,  196,  239,  208,  185,  199,
- /*  1550 */    92,  209,  233,  173,  234,  182,  139,  173,  182,  191,
- /*  1560 */   195,  182,  250,  186,
+ /*  1510 */   218,  189,   40,  157,  218,  157,  240,  240,  157,   38,
+ /*  1520 */   196,  243,  105,  106,  107,  153,  198,  209,  111,  166,
+ /*  1530 */   176,  181,  166,  116,  166,  230,  176,  230,  176,  226,
+ /*  1540 */   199,  177,  239,  209,  185,  148,  166,  195,  209,  196,
+ /*  1550 */   199,  208,  182,  233,  173,  182,  139,  186,  239,  234,
+ /*  1560 */   191,  182,  173,   92,
 };
 #define YY_SHIFT_USE_DFLT (-70)
-#define YY_SHIFT_COUNT (416)
+#define YY_SHIFT_COUNT (417)
 #define YY_SHIFT_MIN   (-69)
 #define YY_SHIFT_MAX   (1487)
 static const short yy_shift_ofst[] = {
@@ -109561,7 +111561,7 @@ static const short yy_shift_ofst[] = {
  /*   100 */   -45,  -45,  -45,  -45,   -1,   24,  245,  362,  362,  362,
  /*   110 */   362,  362,  362,  362,  362,  362,  362,  362,  362,  362,
  /*   120 */   362,  362,  362,  388,  356,  362,  362,  362,  362,  362,
- /*   130 */   732,  868,  231, 1051, 1458,  -70,  -70,  -70, 1367,   57,
+ /*   130 */   732,  868,  231, 1051, 1471,  -70,  -70,  -70, 1367,   57,
  /*   140 */   434,  434,  289,  291,  285,    1,  204,  572,  539,  362,
  /*   150 */   362,  362,  362,  362,  362,  362,  362,  362,  362,  362,
  /*   160 */   362,  362,  362,  362,  362,  362,  362,  362,  362,  362,
@@ -109571,30 +111571,30 @@ static const short yy_shift_ofst[] = {
  /*   200 */   422,  358,  335,  -12,  -12,  -12,  -12,  576,  294,  -12,
  /*   210 */   -12,  295,  595,  141,  600,  730,  723,  723,  805,  730,
  /*   220 */   805,  439,  911,  231,  865,  231,  865,  807,  865,  723,
- /*   230 */   766,  633,  633,  231,  284,   63,  608, 1476, 1308, 1308,
- /*   240 */  1472, 1472, 1308, 1477, 1425, 1275, 1487, 1487, 1487, 1487,
- /*   250 */  1308, 1461, 1275, 1477, 1425, 1425, 1308, 1461, 1355, 1441,
- /*   260 */  1308, 1308, 1461, 1308, 1461, 1308, 1461, 1442, 1348, 1348,
- /*   270 */  1348, 1408, 1375, 1375, 1442, 1348, 1357, 1348, 1408, 1348,
- /*   280 */  1348, 1316, 1331, 1316, 1331, 1316, 1331, 1308, 1308, 1280,
- /*   290 */  1288, 1289, 1285, 1279, 1275, 1253, 1336, 1346, 1346, 1338,
- /*   300 */  1338, 1338, 1338,  -70,  -70,  -70,  -70,  -70,  -70, 1013,
- /*   310 */   467,  612,   84,  179,  -28,  870,  410,  761,  760,  667,
- /*   320 */   650,  531,  220,  361,  331,  125,  127,   97, 1306, 1300,
- /*   330 */  1270, 1151, 1272, 1203, 1232, 1261, 1244, 1148, 1174, 1139,
- /*   340 */  1156, 1124, 1220, 1115, 1210, 1233, 1099, 1193, 1184, 1174,
- /*   350 */  1173, 1029, 1121, 1120, 1085, 1162, 1119, 1037, 1152, 1147,
- /*   360 */  1129, 1046, 1011, 1093, 1098, 1075, 1061, 1032,  960, 1057,
- /*   370 */  1031, 1030,  899,  938,  982,  936,  972,  958,  910,  955,
- /*   380 */   875,  885,  908,  857,  859,  867,  804,  590,  834,  747,
- /*   390 */   818,  513,  611,  741,  673,  637,  611,  606,  603,  579,
- /*   400 */   501,  541,  468,  386,  445,  395,  376,  281,  185,  120,
- /*   410 */    92,   75,   45,  114,   25,   11,    5,
+ /*   230 */   766,  633,  633,  231,  284,   63,  608, 1481, 1308, 1308,
+ /*   240 */  1472, 1472, 1308, 1477, 1427, 1275, 1487, 1487, 1487, 1487,
+ /*   250 */  1308, 1461, 1275, 1477, 1427, 1427, 1275, 1308, 1461, 1355,
+ /*   260 */  1441, 1308, 1308, 1461, 1308, 1461, 1308, 1461, 1442, 1348,
+ /*   270 */  1348, 1348, 1408, 1375, 1375, 1442, 1348, 1357, 1348, 1408,
+ /*   280 */  1348, 1348, 1316, 1331, 1316, 1331, 1316, 1331, 1308, 1308,
+ /*   290 */  1280, 1288, 1289, 1285, 1279, 1275, 1253, 1336, 1346, 1346,
+ /*   300 */  1338, 1338, 1338, 1338,  -70,  -70,  -70,  -70,  -70,  -70,
+ /*   310 */  1013,  467,  612,   84,  179,  -28,  870,  410,  761,  760,
+ /*   320 */   667,  650,  531,  220,  361,  331,  125,  127,   97, 1306,
+ /*   330 */  1300, 1270, 1151, 1272, 1203, 1232, 1261, 1244, 1148, 1174,
+ /*   340 */  1139, 1156, 1124, 1220, 1115, 1210, 1233, 1099, 1193, 1184,
+ /*   350 */  1174, 1173, 1029, 1121, 1120, 1085, 1162, 1119, 1037, 1152,
+ /*   360 */  1147, 1129, 1046, 1011, 1093, 1098, 1075, 1061, 1032,  960,
+ /*   370 */  1057, 1031, 1030,  899,  938,  982,  936,  972,  958,  910,
+ /*   380 */   955,  875,  885,  908,  857,  859,  867,  804,  590,  834,
+ /*   390 */   747,  818,  513,  611,  741,  673,  637,  611,  606,  603,
+ /*   400 */   579,  501,  541,  468,  386,  445,  395,  376,  281,  185,
+ /*   410 */   120,   92,   75,   45,  114,   25,   11,    5,
 };
 #define YY_REDUCE_USE_DFLT (-169)
-#define YY_REDUCE_COUNT (308)
+#define YY_REDUCE_COUNT (309)
 #define YY_REDUCE_MIN   (-168)
-#define YY_REDUCE_MAX   (1391)
+#define YY_REDUCE_MAX   (1397)
 static const short yy_reduce_ofst[] = {
  /*     0 */  -141,   90, 1095,  222,  158,  156,   19,   17,   10, -104,
  /*    10 */   378,  316,  311,   12,  180,  249,  598,  464,  397, 1181,
@@ -109615,83 +111615,83 @@ static const short yy_reduce_ofst[] = {
  /*   160 */  1140, 1135, 1123, 1112, 1107, 1100, 1080, 1074, 1073, 1072,
  /*   170 */  1070, 1067, 1048, 1044,  969,  968,  907,  906,  904,  894,
  /*   180 */   833,  837,  836,  340,  827,  815,  775,   68,  722,  646,
- /*   190 */  -168, 1384, 1380, 1377, 1379, 1376, 1373, 1339, 1365, 1368,
- /*   200 */  1365, 1365, 1365, 1365, 1365, 1365, 1365, 1320, 1319, 1365,
- /*   210 */  1365, 1339, 1378, 1349, 1391, 1350, 1342, 1334, 1307, 1341,
- /*   220 */  1293, 1364, 1363, 1371, 1362, 1370, 1359, 1340, 1354, 1333,
- /*   230 */  1305, 1304, 1299, 1361, 1328, 1324, 1366, 1282, 1360, 1358,
- /*   240 */  1278, 1276, 1356, 1292, 1322, 1309, 1317, 1315, 1314, 1312,
- /*   250 */  1345, 1347, 1302, 1277, 1311, 1303, 1337, 1335, 1252, 1248,
- /*   260 */  1332, 1330, 1329, 1327, 1326, 1323, 1321, 1297, 1301, 1295,
- /*   270 */  1294, 1290, 1243, 1240, 1284, 1291, 1286, 1283, 1274, 1281,
- /*   280 */  1271, 1238, 1241, 1236, 1235, 1227, 1226, 1267, 1266, 1189,
- /*   290 */  1229, 1223, 1211, 1206, 1201, 1197, 1239, 1237, 1219, 1216,
- /*   300 */  1209, 1208, 1185, 1089, 1086, 1087, 1137, 1136, 1164,
+ /*   190 */  -168, 1389, 1381, 1371, 1379, 1373, 1370, 1343, 1352, 1369,
+ /*   200 */  1352, 1352, 1352, 1352, 1352, 1352, 1352, 1325, 1320, 1352,
+ /*   210 */  1352, 1343, 1380, 1353, 1397, 1351, 1339, 1334, 1319, 1341,
+ /*   220 */  1303, 1364, 1359, 1368, 1362, 1366, 1360, 1350, 1354, 1318,
+ /*   230 */  1313, 1307, 1305, 1363, 1328, 1324, 1372, 1278, 1361, 1358,
+ /*   240 */  1277, 1276, 1356, 1296, 1322, 1309, 1317, 1315, 1314, 1312,
+ /*   250 */  1345, 1347, 1302, 1292, 1311, 1304, 1293, 1337, 1335, 1252,
+ /*   260 */  1248, 1332, 1330, 1329, 1327, 1326, 1323, 1321, 1297, 1301,
+ /*   270 */  1295, 1294, 1290, 1243, 1240, 1284, 1291, 1286, 1283, 1274,
+ /*   280 */  1281, 1271, 1238, 1241, 1236, 1235, 1227, 1226, 1267, 1266,
+ /*   290 */  1189, 1229, 1223, 1211, 1206, 1201, 1197, 1239, 1237, 1219,
+ /*   300 */  1216, 1209, 1208, 1185, 1089, 1086, 1087, 1137, 1136, 1164,
 };
 static const YYACTIONTYPE yy_default[] = {
- /*     0 */   632,  866,  954,  954,  866,  866,  954,  954,  954,  756,
- /*    10 */   954,  954,  954,  864,  954,  954,  784,  784,  928,  954,
- /*    20 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*    30 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*    40 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*    50 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*    60 */   954,  954,  954,  954,  954,  954,  954,  671,  760,  790,
- /*    70 */   954,  954,  954,  954,  954,  954,  954,  954,  927,  929,
- /*    80 */   798,  797,  907,  771,  795,  788,  792,  867,  860,  861,
- /*    90 */   859,  863,  868,  954,  791,  827,  844,  826,  838,  843,
- /*   100 */   850,  842,  839,  829,  828,  830,  831,  954,  954,  954,
- /*   110 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*   120 */   954,  954,  954,  658,  725,  954,  954,  954,  954,  954,
- /*   130 */   954,  954,  954,  832,  833,  847,  846,  845,  954,  663,
- /*   140 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*   150 */   934,  932,  954,  879,  954,  954,  954,  954,  954,  954,
- /*   160 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*   170 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*   180 */   638,  756,  756,  756,  632,  954,  954,  954,  946,  760,
- /*   190 */   750,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*   200 */   954,  954,  954,  800,  739,  917,  919,  954,  900,  737,
- /*   210 */   660,  758,  673,  748,  640,  794,  773,  773,  912,  794,
- /*   220 */   912,  696,  719,  954,  784,  954,  784,  693,  784,  773,
- /*   230 */   862,  954,  954,  954,  757,  748,  954,  939,  764,  764,
- /*   240 */   931,  931,  764,  806,  729,  794,  736,  736,  736,  736,
- /*   250 */   764,  655,  794,  806,  729,  729,  764,  655,  906,  904,
- /*   260 */   764,  764,  655,  764,  655,  764,  655,  872,  727,  727,
- /*   270 */   727,  711,  876,  876,  872,  727,  696,  727,  711,  727,
- /*   280 */   727,  777,  772,  777,  772,  777,  772,  764,  764,  954,
- /*   290 */   789,  778,  787,  785,  794,  954,  714,  648,  648,  637,
- /*   300 */   637,  637,  637,  951,  951,  946,  698,  698,  681,  954,
- /*   310 */   954,  954,  954,  954,  954,  954,  881,  954,  954,  954,
- /*   320 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  633,
- /*   330 */   941,  954,  954,  938,  954,  954,  954,  954,  799,  954,
- /*   340 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  916,
- /*   350 */   954,  954,  954,  954,  954,  954,  954,  910,  954,  954,
- /*   360 */   954,  954,  954,  954,  903,  902,  954,  954,  954,  954,
- /*   370 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*   380 */   954,  954,  954,  954,  954,  954,  954,  954,  954,  954,
- /*   390 */   954,  954,  786,  954,  779,  954,  865,  954,  954,  954,
- /*   400 */   954,  954,  954,  954,  954,  954,  954,  742,  815,  954,
- /*   410 */   814,  818,  813,  665,  954,  646,  954,  629,  634,  950,
- /*   420 */   953,  952,  949,  948,  947,  942,  940,  937,  936,  935,
- /*   430 */   933,  930,  926,  885,  883,  890,  889,  888,  887,  886,
- /*   440 */   884,  882,  880,  801,  796,  793,  925,  878,  738,  735,
- /*   450 */   734,  654,  943,  909,  918,  805,  804,  807,  915,  914,
- /*   460 */   913,  911,  908,  895,  803,  802,  730,  870,  869,  657,
- /*   470 */   899,  898,  897,  901,  905,  896,  766,  656,  653,  662,
- /*   480 */   717,  718,  726,  724,  723,  722,  721,  720,  716,  664,
- /*   490 */   672,  710,  695,  694,  875,  877,  874,  873,  703,  702,
- /*   500 */   708,  707,  706,  705,  704,  701,  700,  699,  692,  691,
- /*   510 */   697,  690,  713,  712,  709,  689,  733,  732,  731,  728,
- /*   520 */   688,  687,  686,  818,  685,  684,  824,  823,  811,  854,
- /*   530 */   753,  752,  751,  763,  762,  775,  774,  809,  808,  776,
- /*   540 */   761,  755,  754,  770,  769,  768,  767,  759,  749,  781,
- /*   550 */   783,  782,  780,  856,  765,  853,  924,  923,  922,  921,
- /*   560 */   920,  858,  857,  825,  822,  676,  677,  893,  892,  894,
- /*   570 */   891,  679,  678,  675,  674,  855,  744,  743,  851,  848,
- /*   580 */   840,  836,  852,  849,  841,  837,  835,  834,  820,  819,
- /*   590 */   817,  816,  812,  821,  667,  745,  741,  740,  810,  747,
- /*   600 */   746,  683,  682,  680,  661,  659,  652,  650,  649,  651,
- /*   610 */   647,  645,  644,  643,  642,  641,  670,  669,  668,  666,
- /*   620 */   665,  639,  636,  635,  631,  630,  628,
+ /*     0 */   633,  867,  955,  955,  867,  867,  955,  955,  955,  757,
+ /*    10 */   955,  955,  955,  865,  955,  955,  785,  785,  929,  955,
+ /*    20 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*    30 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*    40 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*    50 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*    60 */   955,  955,  955,  955,  955,  955,  955,  672,  761,  791,
+ /*    70 */   955,  955,  955,  955,  955,  955,  955,  955,  928,  930,
+ /*    80 */   799,  798,  908,  772,  796,  789,  793,  868,  861,  862,
+ /*    90 */   860,  864,  869,  955,  792,  828,  845,  827,  839,  844,
+ /*   100 */   851,  843,  840,  830,  829,  831,  832,  955,  955,  955,
+ /*   110 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   120 */   955,  955,  955,  659,  726,  955,  955,  955,  955,  955,
+ /*   130 */   955,  955,  955,  833,  834,  848,  847,  846,  955,  664,
+ /*   140 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   150 */   935,  933,  955,  880,  955,  955,  955,  955,  955,  955,
+ /*   160 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   170 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   180 */   639,  757,  757,  757,  633,  955,  955,  955,  947,  761,
+ /*   190 */   751,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   200 */   955,  955,  955,  801,  740,  918,  920,  955,  901,  738,
+ /*   210 */   661,  759,  674,  749,  641,  795,  774,  774,  913,  795,
+ /*   220 */   913,  697,  720,  955,  785,  955,  785,  694,  785,  774,
+ /*   230 */   863,  955,  955,  955,  758,  749,  955,  940,  765,  765,
+ /*   240 */   932,  932,  765,  807,  730,  795,  737,  737,  737,  737,
+ /*   250 */   765,  656,  795,  807,  730,  730,  795,  765,  656,  907,
+ /*   260 */   905,  765,  765,  656,  765,  656,  765,  656,  873,  728,
+ /*   270 */   728,  728,  712,  877,  877,  873,  728,  697,  728,  712,
+ /*   280 */   728,  728,  778,  773,  778,  773,  778,  773,  765,  765,
+ /*   290 */   955,  790,  779,  788,  786,  795,  955,  715,  649,  649,
+ /*   300 */   638,  638,  638,  638,  952,  952,  947,  699,  699,  682,
+ /*   310 */   955,  955,  955,  955,  955,  955,  955,  882,  955,  955,
+ /*   320 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   330 */   634,  942,  955,  955,  939,  955,  955,  955,  955,  800,
+ /*   340 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   350 */   917,  955,  955,  955,  955,  955,  955,  955,  911,  955,
+ /*   360 */   955,  955,  955,  955,  955,  904,  903,  955,  955,  955,
+ /*   370 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   380 */   955,  955,  955,  955,  955,  955,  955,  955,  955,  955,
+ /*   390 */   955,  955,  955,  787,  955,  780,  955,  866,  955,  955,
+ /*   400 */   955,  955,  955,  955,  955,  955,  955,  955,  743,  816,
+ /*   410 */   955,  815,  819,  814,  666,  955,  647,  955,  630,  635,
+ /*   420 */   951,  954,  953,  950,  949,  948,  943,  941,  938,  937,
+ /*   430 */   936,  934,  931,  927,  886,  884,  891,  890,  889,  888,
+ /*   440 */   887,  885,  883,  881,  802,  797,  794,  926,  879,  739,
+ /*   450 */   736,  735,  655,  944,  910,  919,  806,  805,  808,  916,
+ /*   460 */   915,  914,  912,  909,  896,  804,  803,  731,  871,  870,
+ /*   470 */   658,  900,  899,  898,  902,  906,  897,  767,  657,  654,
+ /*   480 */   663,  718,  719,  727,  725,  724,  723,  722,  721,  717,
+ /*   490 */   665,  673,  711,  696,  695,  876,  878,  875,  874,  704,
+ /*   500 */   703,  709,  708,  707,  706,  705,  702,  701,  700,  693,
+ /*   510 */   692,  698,  691,  714,  713,  710,  690,  734,  733,  732,
+ /*   520 */   729,  689,  688,  687,  819,  686,  685,  825,  824,  812,
+ /*   530 */   855,  754,  753,  752,  764,  763,  776,  775,  810,  809,
+ /*   540 */   777,  762,  756,  755,  771,  770,  769,  768,  760,  750,
+ /*   550 */   782,  784,  783,  781,  857,  766,  854,  925,  924,  923,
+ /*   560 */   922,  921,  859,  858,  826,  823,  677,  678,  894,  893,
+ /*   570 */   895,  892,  680,  679,  676,  675,  856,  745,  744,  852,
+ /*   580 */   849,  841,  837,  853,  850,  842,  838,  836,  835,  821,
+ /*   590 */   820,  818,  817,  813,  822,  668,  746,  742,  741,  811,
+ /*   600 */   748,  747,  684,  683,  681,  662,  660,  653,  651,  650,
+ /*   610 */   652,  648,  646,  645,  644,  643,  642,  671,  670,  669,
+ /*   620 */   667,  666,  640,  637,  636,  632,  631,  629,
 };
 
 /* The next table maps tokens into fallback tokens.  If a construct
@@ -110163,7 +112163,7 @@ static const char *const yyRuleName[] = {
  /* 239 */ "exprlist ::=",
  /* 240 */ "nexprlist ::= nexprlist COMMA expr",
  /* 241 */ "nexprlist ::= expr",
- /* 242 */ "cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP",
+ /* 242 */ "cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP where_opt",
  /* 243 */ "uniqueflag ::= UNIQUE",
  /* 244 */ "uniqueflag ::=",
  /* 245 */ "idxlist_opt ::=",
@@ -110882,7 +112882,7 @@ static const struct {
   { 220, 0 },
   { 215, 3 },
   { 215, 1 },
-  { 147, 11 },
+  { 147, 12 },
   { 227, 1 },
   { 227, 0 },
   { 178, 0 },
@@ -111087,8 +113087,6 @@ static void yy_reduce(
       case 86: /* init_deferred_pred_opt ::= INITIALLY IMMEDIATE */ yytestcase(yyruleno==86);
       case 98: /* defer_subclause_opt ::= */ yytestcase(yyruleno==98);
       case 109: /* ifexists ::= */ yytestcase(yyruleno==109);
-      case 120: /* distinct ::= ALL */ yytestcase(yyruleno==120);
-      case 121: /* distinct ::= */ yytestcase(yyruleno==121);
       case 221: /* between_op ::= BETWEEN */ yytestcase(yyruleno==221);
       case 224: /* in_op ::= IN */ yytestcase(yyruleno==224);
 {yygotominor.yy392 = 0;}
@@ -111098,7 +113096,6 @@ static void yy_reduce(
       case 70: /* autoinc ::= AUTOINCR */ yytestcase(yyruleno==70);
       case 85: /* init_deferred_pred_opt ::= INITIALLY DEFERRED */ yytestcase(yyruleno==85);
       case 108: /* ifexists ::= IF EXISTS */ yytestcase(yyruleno==108);
-      case 119: /* distinct ::= DISTINCT */ yytestcase(yyruleno==119);
       case 222: /* between_op ::= NOT BETWEEN */ yytestcase(yyruleno==222);
       case 225: /* in_op ::= NOT IN */ yytestcase(yyruleno==225);
 {yygotominor.yy392 = 1;}
@@ -111327,6 +113324,7 @@ static void yy_reduce(
   if( yymsp[0].minor.yy159 ){
     yymsp[0].minor.yy159->op = (u8)yymsp[-1].minor.yy392;
     yymsp[0].minor.yy159->pPrior = yymsp[-2].minor.yy159;
+    if( yymsp[-1].minor.yy392!=TK_ALL ) pParse->hasCompound = 1;
   }else{
     sqlite3SelectDelete(pParse->db, yymsp[-2].minor.yy159);
   }
@@ -111338,9 +113336,16 @@ static void yy_reduce(
         break;
       case 118: /* oneselect ::= SELECT distinct selcollist from where_opt groupby_opt having_opt orderby_opt limit_opt */
 {
-  yygotominor.yy159 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy442,yymsp[-5].minor.yy347,yymsp[-4].minor.yy122,yymsp[-3].minor.yy442,yymsp[-2].minor.yy122,yymsp[-1].minor.yy442,yymsp[-7].minor.yy392,yymsp[0].minor.yy64.pLimit,yymsp[0].minor.yy64.pOffset);
+  yygotominor.yy159 = sqlite3SelectNew(pParse,yymsp[-6].minor.yy442,yymsp[-5].minor.yy347,yymsp[-4].minor.yy122,yymsp[-3].minor.yy442,yymsp[-2].minor.yy122,yymsp[-1].minor.yy442,yymsp[-7].minor.yy305,yymsp[0].minor.yy64.pLimit,yymsp[0].minor.yy64.pOffset);
 }
         break;
+      case 119: /* distinct ::= DISTINCT */
+{yygotominor.yy305 = SF_Distinct;}
+        break;
+      case 120: /* distinct ::= ALL */
+      case 121: /* distinct ::= */ yytestcase(yyruleno==121);
+{yygotominor.yy305 = 0;}
+        break;
       case 122: /* sclp ::= selcollist COMMA */
       case 246: /* idxlist_opt ::= LP idxlist RP */ yytestcase(yyruleno==246);
 {yygotominor.yy442 = yymsp[-1].minor.yy442;}
@@ -111409,10 +113414,22 @@ static void yy_reduce(
 {
     if( yymsp[-6].minor.yy347==0 && yymsp[-2].minor.yy0.n==0 && yymsp[-1].minor.yy122==0 && yymsp[0].minor.yy180==0 ){
       yygotominor.yy347 = yymsp[-4].minor.yy347;
+    }else if( yymsp[-4].minor.yy347->nSrc==1 ){
+      yygotominor.yy347 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy347,0,0,&yymsp[-2].minor.yy0,0,yymsp[-1].minor.yy122,yymsp[0].minor.yy180);
+      if( yygotominor.yy347 ){
+        struct SrcList_item *pNew = &yygotominor.yy347->a[yygotominor.yy347->nSrc-1];
+        struct SrcList_item *pOld = yymsp[-4].minor.yy347->a;
+        pNew->zName = pOld->zName;
+        pNew->zDatabase = pOld->zDatabase;
+        pNew->pSelect = pOld->pSelect;
+        pOld->zName = pOld->zDatabase = 0;
+        pOld->pSelect = 0;
+      }
+      sqlite3SrcListDelete(pParse->db, yymsp[-4].minor.yy347);
     }else{
       Select *pSubquery;
       sqlite3SrcListShiftJoinType(yymsp[-4].minor.yy347);
-      pSubquery = sqlite3SelectNew(pParse,0,yymsp[-4].minor.yy347,0,0,0,0,0,0,0);
+      pSubquery = sqlite3SelectNew(pParse,0,yymsp[-4].minor.yy347,0,0,0,0,SF_NestedFrom,0,0);
       yygotominor.yy347 = sqlite3SrcListAppendFromTerm(pParse,yymsp[-6].minor.yy347,0,0,&yymsp[-2].minor.yy0,pSubquery,yymsp[-1].minor.yy122,yymsp[0].minor.yy180);
     }
   }
@@ -111627,7 +113644,7 @@ static void yy_reduce(
         break;
       case 194: /* expr ::= expr COLLATE ids */
 {
-  yygotominor.yy342.pExpr = sqlite3ExprSetCollByToken(pParse, yymsp[-2].minor.yy342.pExpr, &yymsp[0].minor.yy0);
+  yygotominor.yy342.pExpr = sqlite3ExprAddCollateToken(pParse, yymsp[-2].minor.yy342.pExpr, &yymsp[0].minor.yy0);
   yygotominor.yy342.zStart = yymsp[-2].minor.yy342.zStart;
   yygotominor.yy342.zEnd = &yymsp[0].minor.yy0.z[yymsp[0].minor.yy0.n];
 }
@@ -111645,7 +113662,7 @@ static void yy_reduce(
   }
   yygotominor.yy342.pExpr = sqlite3ExprFunction(pParse, yymsp[-1].minor.yy442, &yymsp[-4].minor.yy0);
   spanSet(&yygotominor.yy342,&yymsp[-4].minor.yy0,&yymsp[0].minor.yy0);
-  if( yymsp[-2].minor.yy392 && yygotominor.yy342.pExpr ){
+  if( yymsp[-2].minor.yy305 && yygotominor.yy342.pExpr ){
     yygotominor.yy342.pExpr->flags |= EP_Distinct;
   }
 }
@@ -111870,11 +113887,11 @@ static void yy_reduce(
       case 241: /* nexprlist ::= expr */
 {yygotominor.yy442 = sqlite3ExprListAppend(pParse,0,yymsp[0].minor.yy342.pExpr);}
         break;
-      case 242: /* cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP */
+      case 242: /* cmd ::= createkw uniqueflag INDEX ifnotexists nm dbnm ON nm LP idxlist RP where_opt */
 {
-  sqlite3CreateIndex(pParse, &yymsp[-6].minor.yy0, &yymsp[-5].minor.yy0, 
-                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-3].minor.yy0,0), yymsp[-1].minor.yy442, yymsp[-9].minor.yy392,
-                      &yymsp[-10].minor.yy0, &yymsp[0].minor.yy0, SQLITE_SO_ASC, yymsp[-7].minor.yy392);
+  sqlite3CreateIndex(pParse, &yymsp[-7].minor.yy0, &yymsp[-6].minor.yy0, 
+                     sqlite3SrcListAppend(pParse->db,0,&yymsp[-4].minor.yy0,0), yymsp[-2].minor.yy442, yymsp[-10].minor.yy392,
+                      &yymsp[-11].minor.yy0, yymsp[0].minor.yy122, SQLITE_SO_ASC, yymsp[-8].minor.yy392);
 }
         break;
       case 243: /* uniqueflag ::= UNIQUE */
@@ -111886,11 +113903,7 @@ static void yy_reduce(
         break;
       case 247: /* idxlist ::= idxlist COMMA nm collate sortorder */
 {
-  Expr *p = 0;
-  if( yymsp[-1].minor.yy0.n>0 ){
-    p = sqlite3Expr(pParse->db, TK_COLUMN, 0);
-    sqlite3ExprSetCollByToken(pParse, p, &yymsp[-1].minor.yy0);
-  }
+  Expr *p = sqlite3ExprAddCollateToken(pParse, 0, &yymsp[-1].minor.yy0);
   yygotominor.yy442 = sqlite3ExprListAppend(pParse,yymsp[-4].minor.yy442, p);
   sqlite3ExprListSetName(pParse,yygotominor.yy442,&yymsp[-2].minor.yy0,1);
   sqlite3ExprListCheckLength(pParse, yygotominor.yy442, "index");
@@ -111899,11 +113912,7 @@ static void yy_reduce(
         break;
       case 248: /* idxlist ::= nm collate sortorder */
 {
-  Expr *p = 0;
-  if( yymsp[-1].minor.yy0.n>0 ){
-    p = sqlite3PExpr(pParse, TK_COLUMN, 0, 0, 0);
-    sqlite3ExprSetCollByToken(pParse, p, &yymsp[-1].minor.yy0);
-  }
+  Expr *p = sqlite3ExprAddCollateToken(pParse, 0, &yymsp[-1].minor.yy0);
   yygotominor.yy442 = sqlite3ExprListAppend(pParse,0, p);
   sqlite3ExprListSetName(pParse, yygotominor.yy442, &yymsp[-2].minor.yy0, 1);
   sqlite3ExprListCheckLength(pParse, yygotominor.yy442, "index");
@@ -112152,6 +114161,7 @@ static void yy_reduce(
       /* (326) anylist ::= anylist ANY */ yytestcase(yyruleno==326);
         break;
   };
+  assert( yyruleno>=0 && yyruleno<sizeof(yyRuleInfo)/sizeof(yyRuleInfo[0]) );
   yygoto = yyRuleInfo[yyruleno].lhs;
   yysize = yyRuleInfo[yyruleno].nrhs;
   yypParser->yyidx -= yysize;
@@ -112807,7 +114817,6 @@ SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *z, int *tokenType){
     }
     case '-': {
       if( z[1]=='-' ){
-        /* IMP: R-50417-27976 -- syntax diagram for comments */
         for(i=2; (c=z[i])!=0 && c!='\n'; i++){}
         *tokenType = TK_SPACE;   /* IMP: R-22934-25134 */
         return i;
@@ -112840,7 +114849,6 @@ SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *z, int *tokenType){
         *tokenType = TK_SLASH;
         return 1;
       }
-      /* IMP: R-50417-27976 -- syntax diagram for comments */
       for(i=3, c=z[2]; (c!='*' || z[i]!='/') && (c=z[i])!=0; i++){}
       if( c ) i++;
       *tokenType = TK_SPACE;   /* IMP: R-22934-25134 */
@@ -113080,7 +115088,7 @@ SQLITE_PRIVATE int sqlite3RunParser(Parse *pParse, const char *zSql, char **pzEr
 
 
   mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
-  if( db->activeVdbeCnt==0 ){
+  if( db->nVdbeActive==0 ){
     db->u1.isInterrupted = 0;
   }
   pParse->rc = SQLITE_OK;
@@ -113702,6 +115710,9 @@ SQLITE_API char *sqlite3_data_directory = 0;
 SQLITE_API int sqlite3_initialize(void){
   MUTEX_LOGIC( sqlite3_mutex *pMaster; )       /* The main static mutex */
   int rc;                                      /* Result code */
+#ifdef SQLITE_EXTRA_INIT
+  int bRunExtraInit = 0;                       /* Extra initialization needed */
+#endif
 
 #ifdef SQLITE_OMIT_WSD
   rc = sqlite3_wsd_init(4096, 24);
@@ -113717,6 +115728,13 @@ SQLITE_API int sqlite3_initialize(void){
   */
   if( sqlite3GlobalConfig.isInit ) return SQLITE_OK;
 
+#ifdef SQLITE_ENABLE_SQLLOG
+  {
+    extern void sqlite3_init_sqllog(void);
+    sqlite3_init_sqllog();
+  }
+#endif
+
   /* Make sure the mutex subsystem is initialized.  If unable to 
   ** initialize the mutex subsystem, return early with the error.
   ** If the system is so sick that we are unable to allocate a mutex,
@@ -113792,6 +115810,9 @@ SQLITE_API int sqlite3_initialize(void){
       sqlite3PCacheBufferSetup( sqlite3GlobalConfig.pPage, 
           sqlite3GlobalConfig.szPage, sqlite3GlobalConfig.nPage);
       sqlite3GlobalConfig.isInit = 1;
+#ifdef SQLITE_EXTRA_INIT
+      bRunExtraInit = 1;
+#endif
     }
     sqlite3GlobalConfig.inProgress = 0;
   }
@@ -113832,7 +115853,7 @@ SQLITE_API int sqlite3_initialize(void){
   ** compile-time option.
   */
 #ifdef SQLITE_EXTRA_INIT
-  if( rc==SQLITE_OK && sqlite3GlobalConfig.isInit ){
+  if( bRunExtraInit ){
     int SQLITE_EXTRA_INIT(const char*);
     rc = SQLITE_EXTRA_INIT(0);
   }
@@ -114020,8 +116041,8 @@ SQLITE_API int sqlite3_config(int op, ...){
         memset(&sqlite3GlobalConfig.m, 0, sizeof(sqlite3GlobalConfig.m));
       }else{
         /* The heap pointer is not NULL, then install one of the
-        ** mem5.c/mem3.c methods. If neither ENABLE_MEMSYS3 nor
-        ** ENABLE_MEMSYS5 is defined, return an error.
+        ** mem5.c/mem3.c methods.  The enclosing #if guarantees at
+        ** least one of these methods is currently enabled.
         */
 #ifdef SQLITE_ENABLE_MEMSYS3
         sqlite3GlobalConfig.m = *sqlite3MemGetMemsys3();
@@ -114040,7 +116061,7 @@ SQLITE_API int sqlite3_config(int op, ...){
       break;
     }
     
-    /* Record a pointer to the logger funcction and its first argument.
+    /* Record a pointer to the logger function and its first argument.
     ** The default is NULL.  Logging is disabled if the function pointer is
     ** NULL.
     */
@@ -114060,6 +116081,33 @@ SQLITE_API int sqlite3_config(int op, ...){
       break;
     }
 
+    case SQLITE_CONFIG_COVERING_INDEX_SCAN: {
+      sqlite3GlobalConfig.bUseCis = va_arg(ap, int);
+      break;
+    }
+
+#ifdef SQLITE_ENABLE_SQLLOG
+    case SQLITE_CONFIG_SQLLOG: {
+      typedef void(*SQLLOGFUNC_t)(void*, sqlite3*, const char*, int);
+      sqlite3GlobalConfig.xSqllog = va_arg(ap, SQLLOGFUNC_t);
+      sqlite3GlobalConfig.pSqllogArg = va_arg(ap, void *);
+      break;
+    }
+#endif
+
+    case SQLITE_CONFIG_MMAP_SIZE: {
+      sqlite3_int64 szMmap = va_arg(ap, sqlite3_int64);
+      sqlite3_int64 mxMmap = va_arg(ap, sqlite3_int64);
+      if( mxMmap<0 || mxMmap>SQLITE_MAX_MMAP_SIZE ){
+        mxMmap = SQLITE_MAX_MMAP_SIZE;
+      }
+      sqlite3GlobalConfig.mxMmap = mxMmap;
+      if( szMmap<0 ) szMmap = SQLITE_DEFAULT_MMAP_SIZE;
+      if( szMmap>mxMmap) szMmap = mxMmap;
+      sqlite3GlobalConfig.szMmap = szMmap;
+      break;
+    }
+
     default: {
       rc = SQLITE_ERROR;
       break;
@@ -114252,7 +116300,7 @@ static int binCollFunc(
 /*
 ** Another built-in collating sequence: NOCASE. 
 **
-** This collating sequence is intended to be used for "case independant
+** This collating sequence is intended to be used for "case independent
 ** comparison". SQLite's knowledge of upper and lower case equivalents
 ** extends only to the 26 characters used in the English language.
 **
@@ -114350,13 +116398,25 @@ static void disconnectAllVtab(sqlite3 *db){
 #endif
 }
 
+/*
+** Return TRUE if database connection db has unfinalized prepared
+** statements or unfinished sqlite3_backup objects.  
+*/
+static int connectionIsBusy(sqlite3 *db){
+  int j;
+  assert( sqlite3_mutex_held(db->mutex) );
+  if( db->pVdbe ) return 1;
+  for(j=0; j<db->nDb; j++){
+    Btree *pBt = db->aDb[j].pBt;
+    if( pBt && sqlite3BtreeIsInBackup(pBt) ) return 1;
+  }
+  return 0;
+}
+
 /*
 ** Close an existing SQLite database
 */
-SQLITE_API int sqlite3_close(sqlite3 *db){
-  HashElem *i;                    /* Hash table iterator */
-  int j;
-
+static int sqlite3Close(sqlite3 *db, int forceZombie){
   if( !db ){
     return SQLITE_OK;
   }
@@ -114377,24 +116437,75 @@ SQLITE_API int sqlite3_close(sqlite3 *db){
   */
   sqlite3VtabRollback(db);
 
-  /* If there are any outstanding VMs, return SQLITE_BUSY. */
-  if( db->pVdbe ){
-    sqlite3Error(db, SQLITE_BUSY, 
-        "unable to close due to unfinalised statements");
+  /* Legacy behavior (sqlite3_close() behavior) is to return
+  ** SQLITE_BUSY if the connection can not be closed immediately.
+  */
+  if( !forceZombie && connectionIsBusy(db) ){
+    sqlite3Error(db, SQLITE_BUSY, "unable to close due to unfinalized "
+       "statements or unfinished backups");
     sqlite3_mutex_leave(db->mutex);
     return SQLITE_BUSY;
   }
-  assert( sqlite3SafetyCheckSickOrOk(db) );
 
-  for(j=0; j<db->nDb; j++){
-    Btree *pBt = db->aDb[j].pBt;
-    if( pBt && sqlite3BtreeIsInBackup(pBt) ){
-      sqlite3Error(db, SQLITE_BUSY, 
-          "unable to close due to unfinished backup operation");
-      sqlite3_mutex_leave(db->mutex);
-      return SQLITE_BUSY;
-    }
+#ifdef SQLITE_ENABLE_SQLLOG
+  if( sqlite3GlobalConfig.xSqllog ){
+    /* Closing the handle. Fourth parameter is passed the value 2. */
+    sqlite3GlobalConfig.xSqllog(sqlite3GlobalConfig.pSqllogArg, db, 0, 2);
   }
+#endif
+
+  /* Convert the connection into a zombie and then close it.
+  */
+  db->magic = SQLITE_MAGIC_ZOMBIE;
+  sqlite3LeaveMutexAndCloseZombie(db);
+  return SQLITE_OK;
+}
+
+/*
+** Two variations on the public interface for closing a database
+** connection. The sqlite3_close() version returns SQLITE_BUSY and
+** leaves the connection option if there are unfinalized prepared
+** statements or unfinished sqlite3_backups.  The sqlite3_close_v2()
+** version forces the connection to become a zombie if there are
+** unclosed resources, and arranges for deallocation when the last
+** prepare statement or sqlite3_backup closes.
+*/
+SQLITE_API int sqlite3_close(sqlite3 *db){ return sqlite3Close(db,0); }
+SQLITE_API int sqlite3_close_v2(sqlite3 *db){ return sqlite3Close(db,1); }
+
+
+/*
+** Close the mutex on database connection db.
+**
+** Furthermore, if database connection db is a zombie (meaning that there
+** has been a prior call to sqlite3_close(db) or sqlite3_close_v2(db)) and
+** every sqlite3_stmt has now been finalized and every sqlite3_backup has
+** finished, then free all resources.
+*/
+SQLITE_PRIVATE void sqlite3LeaveMutexAndCloseZombie(sqlite3 *db){
+  HashElem *i;                    /* Hash table iterator */
+  int j;
+
+  /* If there are outstanding sqlite3_stmt or sqlite3_backup objects
+  ** or if the connection has not yet been closed by sqlite3_close_v2(),
+  ** then just leave the mutex and return.
+  */
+  if( db->magic!=SQLITE_MAGIC_ZOMBIE || connectionIsBusy(db) ){
+    sqlite3_mutex_leave(db->mutex);
+    return;
+  }
+
+  /* If we reach this point, it means that the database connection has
+  ** closed all sqlite3_stmt and sqlite3_backup objects and has been
+  ** passed to sqlite3_close (meaning that it is a zombie).  Therefore,
+  ** go ahead and free all resources.
+  */
+
+  /* If a transaction is open, roll it back. This also ensures that if
+  ** any database schemas have been modified by an uncommitted transaction
+  ** they are reset. And that the required b-tree mutex is held to make
+  ** the pager rollback and schema reset an atomic operation. */
+  sqlite3RollbackAll(db, SQLITE_OK);
 
   /* Free any outstanding Savepoint structures. */
   sqlite3CloseSavepoints(db);
@@ -114483,7 +116594,6 @@ SQLITE_API int sqlite3_close(sqlite3 *db){
     sqlite3_free(db->lookaside.pStart);
   }
   sqlite3_free(db);
-  return SQLITE_OK;
 }
 
 /*
@@ -114497,6 +116607,15 @@ SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3 *db, int tripCode){
   int inTrans = 0;
   assert( sqlite3_mutex_held(db->mutex) );
   sqlite3BeginBenignMalloc();
+
+  /* Obtain all b-tree mutexes before making any calls to BtreeRollback(). 
+  ** This is important in case the transaction being rolled back has
+  ** modified the database schema. If the b-tree mutexes are not taken
+  ** here, then another shared-cache connection might sneak in between
+  ** the database rollback and schema reset, which can cause false
+  ** corruption reports in some cases.  */
+  sqlite3BtreeEnterAll(db);
+
   for(i=0; i<db->nDb; i++){
     Btree *p = db->aDb[i].pBt;
     if( p ){
@@ -114504,19 +116623,21 @@ SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3 *db, int tripCode){
         inTrans = 1;
       }
       sqlite3BtreeRollback(p, tripCode);
-      db->aDb[i].inTrans = 0;
     }
   }
   sqlite3VtabRollback(db);
   sqlite3EndBenignMalloc();
 
-  if( db->flags&SQLITE_InternChanges ){
+  if( (db->flags&SQLITE_InternChanges)!=0 && db->init.busy==0 ){
     sqlite3ExpirePreparedStatements(db);
     sqlite3ResetAllSchemasOfConnection(db);
   }
+  sqlite3BtreeLeaveAll(db);
 
   /* Any deferred constraint violations have now been resolved. */
   db->nDeferredCons = 0;
+  db->nDeferredImmCons = 0;
+  db->flags &= ~SQLITE_DeferFKs;
 
   /* If one has been configured, invoke the rollback-hook callback */
   if( db->xRollbackCallback && (inTrans || !db->autoCommit) ){
@@ -114524,6 +116645,113 @@ SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3 *db, int tripCode){
   }
 }
 
+/*
+** Return a static string containing the name corresponding to the error code
+** specified in the argument.
+*/
+#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST) || \
+    defined(SQLITE_DEBUG_OS_TRACE)
+SQLITE_PRIVATE const char *sqlite3ErrName(int rc){
+  const char *zName = 0;
+  int i, origRc = rc;
+  for(i=0; i<2 && zName==0; i++, rc &= 0xff){
+    switch( rc ){
+      case SQLITE_OK:                 zName = "SQLITE_OK";                break;
+      case SQLITE_ERROR:              zName = "SQLITE_ERROR";             break;
+      case SQLITE_INTERNAL:           zName = "SQLITE_INTERNAL";          break;
+      case SQLITE_PERM:               zName = "SQLITE_PERM";              break;
+      case SQLITE_ABORT:              zName = "SQLITE_ABORT";             break;
+      case SQLITE_ABORT_ROLLBACK:     zName = "SQLITE_ABORT_ROLLBACK";    break;
+      case SQLITE_BUSY:               zName = "SQLITE_BUSY";              break;
+      case SQLITE_BUSY_RECOVERY:      zName = "SQLITE_BUSY_RECOVERY";     break;
+      case SQLITE_BUSY_SNAPSHOT:      zName = "SQLITE_BUSY_SNAPSHOT";     break;
+      case SQLITE_LOCKED:             zName = "SQLITE_LOCKED";            break;
+      case SQLITE_LOCKED_SHAREDCACHE: zName = "SQLITE_LOCKED_SHAREDCACHE";break;
+      case SQLITE_NOMEM:              zName = "SQLITE_NOMEM";             break;
+      case SQLITE_READONLY:           zName = "SQLITE_READONLY";          break;
+      case SQLITE_READONLY_RECOVERY:  zName = "SQLITE_READONLY_RECOVERY"; break;
+      case SQLITE_READONLY_CANTLOCK:  zName = "SQLITE_READONLY_CANTLOCK"; break;
+      case SQLITE_READONLY_ROLLBACK:  zName = "SQLITE_READONLY_ROLLBACK"; break;
+      case SQLITE_INTERRUPT:          zName = "SQLITE_INTERRUPT";         break;
+      case SQLITE_IOERR:              zName = "SQLITE_IOERR";             break;
+      case SQLITE_IOERR_READ:         zName = "SQLITE_IOERR_READ";        break;
+      case SQLITE_IOERR_SHORT_READ:   zName = "SQLITE_IOERR_SHORT_READ";  break;
+      case SQLITE_IOERR_WRITE:        zName = "SQLITE_IOERR_WRITE";       break;
+      case SQLITE_IOERR_FSYNC:        zName = "SQLITE_IOERR_FSYNC";       break;
+      case SQLITE_IOERR_DIR_FSYNC:    zName = "SQLITE_IOERR_DIR_FSYNC";   break;
+      case SQLITE_IOERR_TRUNCATE:     zName = "SQLITE_IOERR_TRUNCATE";    break;
+      case SQLITE_IOERR_FSTAT:        zName = "SQLITE_IOERR_FSTAT";       break;
+      case SQLITE_IOERR_UNLOCK:       zName = "SQLITE_IOERR_UNLOCK";      break;
+      case SQLITE_IOERR_RDLOCK:       zName = "SQLITE_IOERR_RDLOCK";      break;
+      case SQLITE_IOERR_DELETE:       zName = "SQLITE_IOERR_DELETE";      break;
+      case SQLITE_IOERR_BLOCKED:      zName = "SQLITE_IOERR_BLOCKED";     break;
+      case SQLITE_IOERR_NOMEM:        zName = "SQLITE_IOERR_NOMEM";       break;
+      case SQLITE_IOERR_ACCESS:       zName = "SQLITE_IOERR_ACCESS";      break;
+      case SQLITE_IOERR_CHECKRESERVEDLOCK:
+                                zName = "SQLITE_IOERR_CHECKRESERVEDLOCK"; break;
+      case SQLITE_IOERR_LOCK:         zName = "SQLITE_IOERR_LOCK";        break;
+      case SQLITE_IOERR_CLOSE:        zName = "SQLITE_IOERR_CLOSE";       break;
+      case SQLITE_IOERR_DIR_CLOSE:    zName = "SQLITE_IOERR_DIR_CLOSE";   break;
+      case SQLITE_IOERR_SHMOPEN:      zName = "SQLITE_IOERR_SHMOPEN";     break;
+      case SQLITE_IOERR_SHMSIZE:      zName = "SQLITE_IOERR_SHMSIZE";     break;
+      case SQLITE_IOERR_SHMLOCK:      zName = "SQLITE_IOERR_SHMLOCK";     break;
+      case SQLITE_IOERR_SHMMAP:       zName = "SQLITE_IOERR_SHMMAP";      break;
+      case SQLITE_IOERR_SEEK:         zName = "SQLITE_IOERR_SEEK";        break;
+      case SQLITE_IOERR_DELETE_NOENT: zName = "SQLITE_IOERR_DELETE_NOENT";break;
+      case SQLITE_IOERR_MMAP:         zName = "SQLITE_IOERR_MMAP";        break;
+      case SQLITE_IOERR_GETTEMPPATH:  zName = "SQLITE_IOERR_GETTEMPPATH"; break;
+      case SQLITE_CORRUPT:            zName = "SQLITE_CORRUPT";           break;
+      case SQLITE_CORRUPT_VTAB:       zName = "SQLITE_CORRUPT_VTAB";      break;
+      case SQLITE_NOTFOUND:           zName = "SQLITE_NOTFOUND";          break;
+      case SQLITE_FULL:               zName = "SQLITE_FULL";              break;
+      case SQLITE_CANTOPEN:           zName = "SQLITE_CANTOPEN";          break;
+      case SQLITE_CANTOPEN_NOTEMPDIR: zName = "SQLITE_CANTOPEN_NOTEMPDIR";break;
+      case SQLITE_CANTOPEN_ISDIR:     zName = "SQLITE_CANTOPEN_ISDIR";    break;
+      case SQLITE_CANTOPEN_FULLPATH:  zName = "SQLITE_CANTOPEN_FULLPATH"; break;
+      case SQLITE_PROTOCOL:           zName = "SQLITE_PROTOCOL";          break;
+      case SQLITE_EMPTY:              zName = "SQLITE_EMPTY";             break;
+      case SQLITE_SCHEMA:             zName = "SQLITE_SCHEMA";            break;
+      case SQLITE_TOOBIG:             zName = "SQLITE_TOOBIG";            break;
+      case SQLITE_CONSTRAINT:         zName = "SQLITE_CONSTRAINT";        break;
+      case SQLITE_CONSTRAINT_UNIQUE:  zName = "SQLITE_CONSTRAINT_UNIQUE"; break;
+      case SQLITE_CONSTRAINT_TRIGGER: zName = "SQLITE_CONSTRAINT_TRIGGER";break;
+      case SQLITE_CONSTRAINT_FOREIGNKEY:
+                                zName = "SQLITE_CONSTRAINT_FOREIGNKEY";   break;
+      case SQLITE_CONSTRAINT_CHECK:   zName = "SQLITE_CONSTRAINT_CHECK";  break;
+      case SQLITE_CONSTRAINT_PRIMARYKEY:
+                                zName = "SQLITE_CONSTRAINT_PRIMARYKEY";   break;
+      case SQLITE_CONSTRAINT_NOTNULL: zName = "SQLITE_CONSTRAINT_NOTNULL";break;
+      case SQLITE_CONSTRAINT_COMMITHOOK:
+                                zName = "SQLITE_CONSTRAINT_COMMITHOOK";   break;
+      case SQLITE_CONSTRAINT_VTAB:    zName = "SQLITE_CONSTRAINT_VTAB";   break;
+      case SQLITE_CONSTRAINT_FUNCTION:
+                                zName = "SQLITE_CONSTRAINT_FUNCTION";     break;
+      case SQLITE_MISMATCH:           zName = "SQLITE_MISMATCH";          break;
+      case SQLITE_MISUSE:             zName = "SQLITE_MISUSE";            break;
+      case SQLITE_NOLFS:              zName = "SQLITE_NOLFS";             break;
+      case SQLITE_AUTH:               zName = "SQLITE_AUTH";              break;
+      case SQLITE_FORMAT:             zName = "SQLITE_FORMAT";            break;
+      case SQLITE_RANGE:              zName = "SQLITE_RANGE";             break;
+      case SQLITE_NOTADB:             zName = "SQLITE_NOTADB";            break;
+      case SQLITE_ROW:                zName = "SQLITE_ROW";               break;
+      case SQLITE_NOTICE:             zName = "SQLITE_NOTICE";            break;
+      case SQLITE_NOTICE_RECOVER_WAL: zName = "SQLITE_NOTICE_RECOVER_WAL";break;
+      case SQLITE_NOTICE_RECOVER_ROLLBACK:
+                                zName = "SQLITE_NOTICE_RECOVER_ROLLBACK"; break;
+      case SQLITE_WARNING:            zName = "SQLITE_WARNING";           break;
+      case SQLITE_WARNING_AUTOINDEX:  zName = "SQLITE_WARNING_AUTOINDEX"; break;
+      case SQLITE_DONE:               zName = "SQLITE_DONE";              break;
+    }
+  }
+  if( zName==0 ){
+    static char zBuf[50];
+    sqlite3_snprintf(sizeof(zBuf), zBuf, "SQLITE_UNKNOWN(%d)", origRc);
+    zName = zBuf;
+  }
+  return zName;
+}
+#endif
+
 /*
 ** Return a static string that describes the kind of error specified in the
 ** argument.
@@ -114652,6 +116880,7 @@ SQLITE_API int sqlite3_busy_handler(
   db->busyHandler.xFunc = xBusy;
   db->busyHandler.pArg = pArg;
   db->busyHandler.nBusy = 0;
+  db->busyTimeout = 0;
   sqlite3_mutex_leave(db->mutex);
   return SQLITE_OK;
 }
@@ -114671,7 +116900,7 @@ SQLITE_API void sqlite3_progress_handler(
   sqlite3_mutex_enter(db->mutex);
   if( nOps>0 ){
     db->xProgress = xProgress;
-    db->nProgressOps = nOps;
+    db->nProgressOps = (unsigned)nOps;
     db->pProgressArg = pArg;
   }else{
     db->xProgress = 0;
@@ -114689,8 +116918,8 @@ SQLITE_API void sqlite3_progress_handler(
 */
 SQLITE_API int sqlite3_busy_timeout(sqlite3 *db, int ms){
   if( ms>0 ){
-    db->busyTimeout = ms;
     sqlite3_busy_handler(db, sqliteDefaultBusyCallback, (void*)db);
+    db->busyTimeout = ms;
   }else{
     sqlite3_busy_handler(db, 0, 0);
   }
@@ -114769,7 +116998,7 @@ SQLITE_PRIVATE int sqlite3CreateFunc(
   */
   p = sqlite3FindFunction(db, zFunctionName, nName, nArg, (u8)enc, 0);
   if( p && p->iPrefEnc==enc && p->nArg==nArg ){
-    if( db->activeVdbeCnt ){
+    if( db->nVdbeActive ){
       sqlite3Error(db, SQLITE_BUSY, 
         "unable to delete/modify user-function due to active statements");
       assert( !db->mallocFailed );
@@ -115303,6 +117532,15 @@ SQLITE_API int sqlite3_extended_errcode(sqlite3 *db){
   return db->errCode;
 }
 
+/*
+** Return a string that describes the kind of error specified in the
+** argument.  For now, this simply calls the internal sqlite3ErrStr()
+** function.
+*/
+SQLITE_API const char *sqlite3_errstr(int rc){
+  return sqlite3ErrStr(rc);
+}
+
 /*
 ** Create a new collating function for database "db".  The name is zName
 ** and the encoding is enc.
@@ -115341,7 +117579,7 @@ static int createCollation(
   */
   pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, 0);
   if( pColl && pColl->xCmp ){
-    if( db->activeVdbeCnt ){
+    if( db->nVdbeActive ){
       sqlite3Error(db, SQLITE_BUSY, 
         "unable to delete/modify collation sequence due to active statements");
       return SQLITE_BUSY;
@@ -115539,20 +117777,20 @@ SQLITE_PRIVATE int sqlite3ParseUri(
     zFile = sqlite3_malloc(nByte);
     if( !zFile ) return SQLITE_NOMEM;
 
+    iIn = 5;
+#ifndef SQLITE_ALLOW_URI_AUTHORITY
     /* Discard the scheme and authority segments of the URI. */
     if( zUri[5]=='/' && zUri[6]=='/' ){
       iIn = 7;
       while( zUri[iIn] && zUri[iIn]!='/' ) iIn++;
-
       if( iIn!=7 && (iIn!=16 || memcmp("localhost", &zUri[7], 9)) ){
         *pzErrMsg = sqlite3_mprintf("invalid uri authority: %.*s", 
             iIn-7, &zUri[7]);
         rc = SQLITE_ERROR;
         goto parse_uri_out;
       }
-    }else{
-      iIn = 5;
     }
+#endif
 
     /* Copy the filename and any query parameters into the zFile buffer. 
     ** Decode %HH escape codes along the way. 
@@ -115814,8 +118052,12 @@ static int openDatabase(
   memcpy(db->aLimit, aHardLimit, sizeof(db->aLimit));
   db->autoCommit = 1;
   db->nextAutovac = -1;
+  db->szMmap = sqlite3GlobalConfig.szMmap;
   db->nextPagesize = 0;
-  db->flags |= SQLITE_ShortColNames | SQLITE_AutoIndex | SQLITE_EnableTrigger
+  db->flags |= SQLITE_ShortColNames | SQLITE_EnableTrigger | SQLITE_CacheSpill
+#if !defined(SQLITE_DEFAULT_AUTOMATIC_INDEX) || SQLITE_DEFAULT_AUTOMATIC_INDEX
+                 | SQLITE_AutoIndex
+#endif
 #if SQLITE_DEFAULT_FILE_FORMAT<4
                  | SQLITE_LegacyFileFmt
 #endif
@@ -115972,6 +118214,13 @@ opendb_out:
     db->magic = SQLITE_MAGIC_SICK;
   }
   *ppDb = db;
+#ifdef SQLITE_ENABLE_SQLLOG
+  if( sqlite3GlobalConfig.xSqllog ){
+    /* Opening a db handle. Fourth parameter is passed 0. */
+    void *pArg = sqlite3GlobalConfig.pSqllogArg;
+    sqlite3GlobalConfig.xSqllog(pArg, db, zFilename, 0);
+  }
+#endif
   return sqlite3ApiExit(0, rc);
 }
 
@@ -116148,8 +118397,6 @@ SQLITE_API int sqlite3_global_recover(void){
 ** mode.  Return TRUE if it is and FALSE if not.  Autocommit mode is on
 ** by default.  Autocommit is disabled by a BEGIN statement and reenabled
 ** by the next COMMIT or ROLLBACK.
-**
-******* THIS IS AN EXPERIMENTAL API AND IS SUBJECT TO CHANGE ******
 */
 SQLITE_API int sqlite3_get_autocommit(sqlite3 *db){
   return db->autoCommit;
@@ -116277,7 +118524,7 @@ SQLITE_API int sqlite3_table_column_metadata(
     zDataType = pCol->zType;
     zCollSeq = pCol->zColl;
     notnull = pCol->notNull!=0;
-    primarykey  = pCol->isPrimKey!=0;
+    primarykey  = (pCol->colFlags & COLFLAG_PRIMKEY)!=0;
     autoinc = pTab->iPKey==iCol && (pTab->tabFlags & TF_Autoincrement)!=0;
   }else{
     zDataType = "INTEGER";
@@ -116540,8 +118787,7 @@ SQLITE_API int sqlite3_test_control(int op, ...){
     */
     case SQLITE_TESTCTRL_OPTIMIZATIONS: {
       sqlite3 *db = va_arg(ap, sqlite3*);
-      int x = va_arg(ap,int);
-      db->flags = (x & SQLITE_OptMask) | (db->flags & ~SQLITE_OptMask);
+      db->dbOptFlags = (u16)(va_arg(ap, int) & 0xffff);
       break;
     }
 
@@ -117353,7 +119599,7 @@ SQLITE_PRIVATE void sqlite3ConnectionClosed(sqlite3 *db){
 
 /* If not building as part of the core, include sqlite3ext.h. */
 #ifndef SQLITE_CORE
-SQLITE_API extern const sqlite3_api_routines *sqlite3_api;
+SQLITE_EXTENSION_INIT3
 #endif
 
 /************** Include fts3_tokenizer.h in the middle of fts3Int.h **********/
@@ -117429,7 +119675,7 @@ struct sqlite3_tokenizer_module {
   ** This method should return either SQLITE_OK (0), or an SQLite error 
   ** code. If SQLITE_OK is returned, then *ppTokenizer should be set
   ** to point at the newly created tokenizer structure. The generic
-  ** sqlite3_tokenizer.pModule variable should not be initialised by
+  ** sqlite3_tokenizer.pModule variable should not be initialized by
   ** this callback. The caller will do so.
   */
   int (*xCreate)(
@@ -117534,7 +119780,7 @@ int fts3_term_cnt(int iTerm, int iCol);
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** This is the header file for the generic hash-table implemenation
+** This is the header file for the generic hash-table implementation
 ** used in SQLite.  We've modified it slightly to serve as a standalone
 ** hash table implementation for the full-text indexing module.
 **
@@ -117639,6 +119885,18 @@ SQLITE_PRIVATE Fts3HashElem *sqlite3Fts3HashFindElem(const Fts3Hash *, const voi
 /************** End of fts3_hash.h *******************************************/
 /************** Continuing where we left off in fts3Int.h ********************/
 
+/*
+** This constant determines the maximum depth of an FTS expression tree
+** that the library will create and use. FTS uses recursion to perform 
+** various operations on the query tree, so the disadvantage of a large
+** limit is that it may allow very large queries to use large amounts
+** of stack space (perhaps causing a stack overflow).
+*/
+#ifndef SQLITE_FTS3_MAX_EXPR_DEPTH
+# define SQLITE_FTS3_MAX_EXPR_DEPTH 12
+#endif
+
+
 /*
 ** This constant controls how often segments are merged. Once there are
 ** FTS3_MERGE_COUNT segments of level N, they are merged into a single
@@ -117794,6 +120052,7 @@ struct Fts3Table {
   const char *zName;              /* virtual table name */
   int nColumn;                    /* number of named columns in virtual table */
   char **azColumn;                /* column names.  malloced */
+  u8 *abNotindexed;               /* True for 'notindexed' columns */
   sqlite3_tokenizer *pTokenizer;  /* tokenizer for inserts and queries */
   char *zContentTbl;              /* content=xxx option, or NULL */
   char *zLanguageid;              /* languageid=xxx option, or NULL */
@@ -118021,16 +120280,25 @@ SQLITE_PRIVATE int sqlite3Fts3SegReaderPending(
   Fts3Table*,int,const char*,int,int,Fts3SegReader**);
 SQLITE_PRIVATE void sqlite3Fts3SegReaderFree(Fts3SegReader *);
 SQLITE_PRIVATE int sqlite3Fts3AllSegdirs(Fts3Table*, int, int, int, sqlite3_stmt **);
-SQLITE_PRIVATE int sqlite3Fts3ReadLock(Fts3Table *);
 SQLITE_PRIVATE int sqlite3Fts3ReadBlock(Fts3Table*, sqlite3_int64, char **, int*, int*);
 
 SQLITE_PRIVATE int sqlite3Fts3SelectDoctotal(Fts3Table *, sqlite3_stmt **);
 SQLITE_PRIVATE int sqlite3Fts3SelectDocsize(Fts3Table *, sqlite3_int64, sqlite3_stmt **);
 
+#ifndef SQLITE_DISABLE_FTS4_DEFERRED
 SQLITE_PRIVATE void sqlite3Fts3FreeDeferredTokens(Fts3Cursor *);
 SQLITE_PRIVATE int sqlite3Fts3DeferToken(Fts3Cursor *, Fts3PhraseToken *, int);
 SQLITE_PRIVATE int sqlite3Fts3CacheDeferredDoclists(Fts3Cursor *);
 SQLITE_PRIVATE void sqlite3Fts3FreeDeferredDoclists(Fts3Cursor *);
+SQLITE_PRIVATE int sqlite3Fts3DeferredTokenList(Fts3DeferredToken *, char **, int *);
+#else
+# define sqlite3Fts3FreeDeferredTokens(x)
+# define sqlite3Fts3DeferToken(x,y,z) SQLITE_OK
+# define sqlite3Fts3CacheDeferredDoclists(x) SQLITE_OK
+# define sqlite3Fts3FreeDeferredDoclists(x)
+# define sqlite3Fts3DeferredTokenList(x,y,z) SQLITE_OK
+#endif
+
 SQLITE_PRIVATE void sqlite3Fts3SegmentsClose(Fts3Table *);
 SQLITE_PRIVATE int sqlite3Fts3MaxLevel(Fts3Table *, int *);
 
@@ -118114,7 +120382,7 @@ SQLITE_PRIVATE void sqlite3Fts3Matchinfo(sqlite3_context *, Fts3Cursor *, const
 
 /* fts3_expr.c */
 SQLITE_PRIVATE int sqlite3Fts3ExprParse(sqlite3_tokenizer *, int,
-  char **, int, int, int, const char *, int, Fts3Expr **
+  char **, int, int, int, const char *, int, Fts3Expr **, char **
 );
 SQLITE_PRIVATE void sqlite3Fts3ExprFree(Fts3Expr *);
 #ifdef SQLITE_TEST
@@ -118139,7 +120407,8 @@ SQLITE_PRIVATE int sqlite3Fts3EvalPhrasePoslist(Fts3Cursor *, Fts3Expr *, int iC
 SQLITE_PRIVATE int sqlite3Fts3MsrOvfl(Fts3Cursor *, Fts3MultiSegReader *, int *);
 SQLITE_PRIVATE int sqlite3Fts3MsrIncrRestart(Fts3MultiSegReader *pCsr);
 
-SQLITE_PRIVATE int sqlite3Fts3DeferredTokenList(Fts3DeferredToken *, char **, int *);
+/* fts3_tokenize_vtab.c */
+SQLITE_PRIVATE int sqlite3Fts3InitTok(sqlite3*, Fts3Hash *);
 
 /* fts3_unicode2.c (functions generated by parsing unicode text files) */
 #ifdef SQLITE_ENABLE_FTS4_UNICODE61
@@ -118943,6 +121212,8 @@ static int fts3InitVtab(
   char *zUncompress = 0;          /* uncompress=? parameter (or NULL) */
   char *zContent = 0;             /* content=? parameter (or NULL) */
   char *zLanguageid = 0;          /* languageid=? parameter (or NULL) */
+  char **azNotindexed = 0;        /* The set of notindexed= columns */
+  int nNotindexed = 0;            /* Size of azNotindexed[] array */
 
   assert( strlen(argv[0])==4 );
   assert( (sqlite3_strnicmp(argv[0], "fts4", 4)==0 && isFts4)
@@ -118952,9 +121223,19 @@ static int fts3InitVtab(
   nDb = (int)strlen(argv[1]) + 1;
   nName = (int)strlen(argv[2]) + 1;
 
-  aCol = (const char **)sqlite3_malloc(sizeof(const char *) * (argc-2) );
-  if( !aCol ) return SQLITE_NOMEM;
-  memset((void *)aCol, 0, sizeof(const char *) * (argc-2));
+  nByte = sizeof(const char *) * (argc-2);
+  aCol = (const char **)sqlite3_malloc(nByte);
+  if( aCol ){
+    memset((void*)aCol, 0, nByte);
+    azNotindexed = (char **)sqlite3_malloc(nByte);
+  }
+  if( azNotindexed ){
+    memset(azNotindexed, 0, nByte);
+  }
+  if( !aCol || !azNotindexed ){
+    rc = SQLITE_NOMEM;
+    goto fts3_init_out;
+  }
 
   /* Loop through all of the arguments passed by the user to the FTS3/4
   ** module (i.e. all the column names and special arguments). This loop
@@ -118993,7 +121274,8 @@ static int fts3InitVtab(
         { "uncompress", 10 },     /* 3 -> UNCOMPRESS */
         { "order",       5 },     /* 4 -> ORDER */
         { "content",     7 },     /* 5 -> CONTENT */
-        { "languageid", 10 }      /* 6 -> LANGUAGEID */
+        { "languageid", 10 },     /* 6 -> LANGUAGEID */
+        { "notindexed", 10 }      /* 7 -> NOTINDEXED */
       };
 
       int iOpt;
@@ -119059,6 +121341,11 @@ static int fts3InitVtab(
               zLanguageid = zVal;
               zVal = 0;
               break;
+
+            case 7:              /* NOTINDEXED */
+              azNotindexed[nNotindexed++] = zVal;
+              zVal = 0;
+              break;
           }
         }
         sqlite3_free(zVal);
@@ -119130,6 +121417,7 @@ static int fts3InitVtab(
   nByte = sizeof(Fts3Table) +                  /* Fts3Table */
           nCol * sizeof(char *) +              /* azColumn */
           nIndex * sizeof(struct Fts3Index) +  /* aIndex */
+          nCol * sizeof(u8) +                  /* abNotindexed */
           nName +                              /* zName */
           nDb +                                /* zDb */
           nString;                             /* Space for azColumn strings */
@@ -119163,9 +121451,10 @@ static int fts3InitVtab(
   for(i=0; i<nIndex; i++){
     fts3HashInit(&p->aIndex[i].hPending, FTS3_HASH_STRING, 1);
   }
+  p->abNotindexed = (u8 *)&p->aIndex[nIndex];
 
   /* Fill in the zName and zDb fields of the vtab structure. */
-  zCsr = (char *)&p->aIndex[nIndex];
+  zCsr = (char *)&p->abNotindexed[nCol];
   p->zName = zCsr;
   memcpy(zCsr, argv[2], nName);
   zCsr += nName;
@@ -119186,7 +121475,26 @@ static int fts3InitVtab(
     assert( zCsr <= &((char *)p)[nByte] );
   }
 
-  if( (zCompress==0)!=(zUncompress==0) ){
+  /* Fill in the abNotindexed array */
+  for(iCol=0; iCol<nCol; iCol++){
+    int n = (int)strlen(p->azColumn[iCol]);
+    for(i=0; i<nNotindexed; i++){
+      char *zNot = azNotindexed[i];
+      if( zNot && 0==sqlite3_strnicmp(p->azColumn[iCol], zNot, n) ){
+        p->abNotindexed[iCol] = 1;
+        sqlite3_free(zNot);
+        azNotindexed[i] = 0;
+      }
+    }
+  }
+  for(i=0; i<nNotindexed; i++){
+    if( azNotindexed[i] ){
+      *pzErr = sqlite3_mprintf("no such column: %s", azNotindexed[i]);
+      rc = SQLITE_ERROR;
+    }
+  }
+
+  if( rc==SQLITE_OK && (zCompress==0)!=(zUncompress==0) ){
     char const *zMiss = (zCompress==0 ? "compress" : "uncompress");
     rc = SQLITE_ERROR;
     *pzErr = sqlite3_mprintf("missing %s parameter in fts4 constructor", zMiss);
@@ -119227,7 +121535,9 @@ fts3_init_out:
   sqlite3_free(zUncompress);
   sqlite3_free(zContent);
   sqlite3_free(zLanguageid);
+  for(i=0; i<nNotindexed; i++) sqlite3_free(azNotindexed[i]);
   sqlite3_free((void *)aCol);
+  sqlite3_free((void *)azNotindexed);
   if( rc!=SQLITE_OK ){
     if( p ){
       fts3DisconnectMethod((sqlite3_vtab *)p);
@@ -119285,7 +121595,7 @@ static int fts3BestIndexMethod(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
   ** strategy is possible.
   */
   pInfo->idxNum = FTS3_FULLSCAN_SEARCH;
-  pInfo->estimatedCost = 500000;
+  pInfo->estimatedCost = 5000000;
   for(i=0; i<pInfo->nConstraint; i++){
     struct sqlite3_index_constraint *pCons = &pInfo->aConstraint[i];
     if( pCons->usable==0 ) continue;
@@ -119433,7 +121743,7 @@ static int fts3CursorSeek(sqlite3_context *pContext, Fts3Cursor *pCsr){
       }else{
         rc = sqlite3_reset(pCsr->pStmt);
         if( rc==SQLITE_OK && ((Fts3Table *)pCsr->base.pVtab)->zContentTbl==0 ){
-          /* If no row was found and no error has occured, then the %_content
+          /* If no row was found and no error has occurred, then the %_content
           ** table is missing a row that is present in the full-text index.
           ** The data structures are corrupt.  */
           rc = FTS_CORRUPT_VTAB;
@@ -120673,7 +122983,7 @@ static void fts3SegReaderCursorFree(Fts3MultiSegReader *pSegcsr){
 }
 
 /*
-** This function retreives the doclist for the specified term (or term
+** This function retrieves the doclist for the specified term (or term
 ** prefix) from the database.
 */
 static int fts3TermSelect(
@@ -120837,22 +123147,16 @@ static int fts3FilterMethod(
     pCsr->iLangid = 0;
     if( nVal==2 ) pCsr->iLangid = sqlite3_value_int(apVal[1]);
 
+    assert( p->base.zErrMsg==0 );
     rc = sqlite3Fts3ExprParse(p->pTokenizer, pCsr->iLangid,
-        p->azColumn, p->bFts4, p->nColumn, iCol, zQuery, -1, &pCsr->pExpr
+        p->azColumn, p->bFts4, p->nColumn, iCol, zQuery, -1, &pCsr->pExpr, 
+        &p->base.zErrMsg
     );
     if( rc!=SQLITE_OK ){
-      if( rc==SQLITE_ERROR ){
-        static const char *zErr = "malformed MATCH expression: [%s]";
-        p->base.zErrMsg = sqlite3_mprintf(zErr, zQuery);
-      }
       return rc;
     }
 
-    rc = sqlite3Fts3ReadLock(p);
-    if( rc!=SQLITE_OK ) return rc;
-
     rc = fts3EvalStart(pCsr);
-
     sqlite3Fts3SegmentsClose(p);
     if( rc!=SQLITE_OK ) return rc;
     pCsr->pNextId = pCsr->aDoclist;
@@ -121424,7 +123728,7 @@ SQLITE_PRIVATE void sqlite3Fts3IcuTokenizerModule(sqlite3_tokenizer_module const
 #endif
 
 /*
-** Initialise the fts3 extension. If this extension is built as part
+** Initialize the fts3 extension. If this extension is built as part
 ** of the sqlite library, then this function is called directly by
 ** SQLite. If fts3 is built as a dynamically loadable extension, this
 ** function is called by the sqlite3_extension_init() entry point.
@@ -121458,7 +123762,7 @@ SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db){
   sqlite3Fts3SimpleTokenizerModule(&pSimple);
   sqlite3Fts3PorterTokenizerModule(&pPorter);
 
-  /* Allocate and initialise the hash-table used to store tokenizers. */
+  /* Allocate and initialize the hash-table used to store tokenizers. */
   pHash = sqlite3_malloc(sizeof(Fts3Hash));
   if( !pHash ){
     rc = SQLITE_NOMEM;
@@ -121508,9 +123812,13 @@ SQLITE_PRIVATE int sqlite3Fts3Init(sqlite3 *db){
           db, "fts4", &fts3Module, (void *)pHash, 0
       );
     }
+    if( rc==SQLITE_OK ){
+      rc = sqlite3Fts3InitTok(db, (void *)pHash);
+    }
     return rc;
   }
 
+
   /* An error has occurred. Delete the hash table and return the error code. */
   assert( rc!=SQLITE_OK );
   if( pHash ){
@@ -122298,6 +124606,7 @@ static int fts3EvalStart(Fts3Cursor *pCsr){
   fts3EvalAllocateReaders(pCsr, pCsr->pExpr, &nToken, &nOr, &rc);
 
   /* Determine which, if any, tokens in the expression should be deferred. */
+#ifndef SQLITE_DISABLE_FTS4_DEFERRED
   if( rc==SQLITE_OK && nToken>1 && pTab->bFts4 ){
     Fts3TokenAndCost *aTC;
     Fts3Expr **apOr;
@@ -122328,6 +124637,7 @@ static int fts3EvalStart(Fts3Cursor *pCsr){
       sqlite3_free(aTC);
     }
   }
+#endif
 
   fts3EvalStartReaders(pCsr, pCsr->pExpr, 1, &rc);
   return rc;
@@ -122603,35 +124913,39 @@ static int fts3EvalNearTest(Fts3Expr *pExpr, int *pRc){
       nTmp += p->pRight->pPhrase->doclist.nList;
     }
     nTmp += p->pPhrase->doclist.nList;
-    aTmp = sqlite3_malloc(nTmp*2);
-    if( !aTmp ){
-      *pRc = SQLITE_NOMEM;
+    if( nTmp==0 ){
       res = 0;
     }else{
-      char *aPoslist = p->pPhrase->doclist.pList;
-      int nToken = p->pPhrase->nToken;
+      aTmp = sqlite3_malloc(nTmp*2);
+      if( !aTmp ){
+        *pRc = SQLITE_NOMEM;
+        res = 0;
+      }else{
+        char *aPoslist = p->pPhrase->doclist.pList;
+        int nToken = p->pPhrase->nToken;
 
-      for(p=p->pParent;res && p && p->eType==FTSQUERY_NEAR; p=p->pParent){
-        Fts3Phrase *pPhrase = p->pRight->pPhrase;
-        int nNear = p->nNear;
-        res = fts3EvalNearTrim(nNear, aTmp, &aPoslist, &nToken, pPhrase);
-      }
-  
-      aPoslist = pExpr->pRight->pPhrase->doclist.pList;
-      nToken = pExpr->pRight->pPhrase->nToken;
-      for(p=pExpr->pLeft; p && res; p=p->pLeft){
-        int nNear;
-        Fts3Phrase *pPhrase;
-        assert( p->pParent && p->pParent->pLeft==p );
-        nNear = p->pParent->nNear;
-        pPhrase = (
-            p->eType==FTSQUERY_NEAR ? p->pRight->pPhrase : p->pPhrase
-        );
-        res = fts3EvalNearTrim(nNear, aTmp, &aPoslist, &nToken, pPhrase);
+        for(p=p->pParent;res && p && p->eType==FTSQUERY_NEAR; p=p->pParent){
+          Fts3Phrase *pPhrase = p->pRight->pPhrase;
+          int nNear = p->nNear;
+          res = fts3EvalNearTrim(nNear, aTmp, &aPoslist, &nToken, pPhrase);
+        }
+
+        aPoslist = pExpr->pRight->pPhrase->doclist.pList;
+        nToken = pExpr->pRight->pPhrase->nToken;
+        for(p=pExpr->pLeft; p && res; p=p->pLeft){
+          int nNear;
+          Fts3Phrase *pPhrase;
+          assert( p->pParent && p->pParent->pLeft==p );
+          nNear = p->pParent->nNear;
+          pPhrase = (
+              p->eType==FTSQUERY_NEAR ? p->pRight->pPhrase : p->pPhrase
+              );
+          res = fts3EvalNearTrim(nNear, aTmp, &aPoslist, &nToken, pPhrase);
+        }
       }
+
+      sqlite3_free(aTmp);
     }
-
-    sqlite3_free(aTmp);
   }
 
   return res;
@@ -122711,6 +125025,7 @@ static int fts3EvalTestExpr(
         break;
 
       default: {
+#ifndef SQLITE_DISABLE_FTS4_DEFERRED
         if( pCsr->pDeferred 
          && (pExpr->iDocid==pCsr->iPrevId || pExpr->bDeferred)
         ){
@@ -122722,7 +125037,9 @@ static int fts3EvalTestExpr(
           *pRc = fts3EvalDeferredPhrase(pCsr, pPhrase);
           bHit = (pPhrase->doclist.pList!=0);
           pExpr->iDocid = pCsr->iPrevId;
-        }else{
+        }else
+#endif
+        {
           bHit = (pExpr->bEof==0 && pExpr->iDocid==pCsr->iPrevId);
         }
         break;
@@ -123048,7 +125365,7 @@ SQLITE_PRIVATE int sqlite3Fts3EvalPhraseStats(
 ** of the current row. 
 **
 ** More specifically, the returned buffer contains 1 varint for each 
-** occurence of the phrase in the column, stored using the normal (delta+2) 
+** occurrence of the phrase in the column, stored using the normal (delta+2) 
 ** compression and is terminated by either an 0x01 or 0x00 byte. For example,
 ** if the requested column contains "a b X c d X X" and the position-list
 ** for 'X' is requested, the buffer returned may contain:
@@ -123190,7 +125507,10 @@ SQLITE_PRIVATE int sqlite3Fts3Corrupt(){
 /*
 ** Initialize API pointer table, if required.
 */
-SQLITE_API int sqlite3_extension_init(
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+SQLITE_API int sqlite3_fts3_init(
   sqlite3 *db, 
   char **pzErrMsg,
   const sqlite3_api_routines *pApi
@@ -123275,17 +125595,26 @@ static int fts3auxConnectMethod(
 
   UNUSED_PARAMETER(pUnused);
 
-  /* The user should specify a single argument - the name of an fts3 table. */
-  if( argc!=4 ){
-    *pzErr = sqlite3_mprintf(
-        "wrong number of arguments to fts4aux constructor"
-    );
-    return SQLITE_ERROR;
-  }
+  /* The user should invoke this in one of two forms:
+  **
+  **     CREATE VIRTUAL TABLE xxx USING fts4aux(fts4-table);
+  **     CREATE VIRTUAL TABLE xxx USING fts4aux(fts4-table-db, fts4-table);
+  */
+  if( argc!=4 && argc!=5 ) goto bad_args;
 
   zDb = argv[1]; 
   nDb = (int)strlen(zDb);
-  zFts3 = argv[3];
+  if( argc==5 ){
+    if( nDb==4 && 0==sqlite3_strnicmp("temp", zDb, 4) ){
+      zDb = argv[3]; 
+      nDb = (int)strlen(zDb);
+      zFts3 = argv[4];
+    }else{
+      goto bad_args;
+    }
+  }else{
+    zFts3 = argv[3];
+  }
   nFts3 = (int)strlen(zFts3);
 
   rc = sqlite3_declare_vtab(db, FTS3_TERMS_SCHEMA);
@@ -123308,6 +125637,10 @@ static int fts3auxConnectMethod(
 
   *ppVtab = (sqlite3_vtab *)p;
   return SQLITE_OK;
+
+ bad_args:
+  *pzErr = sqlite3_mprintf("invalid arguments to fts4aux constructor");
+  return SQLITE_ERROR;
 }
 
 /*
@@ -123787,7 +126120,7 @@ struct ParseContext {
 ** This function is equivalent to the standard isspace() function. 
 **
 ** The standard isspace() can be awkward to use safely, because although it
-** is defined to accept an argument of type int, its behaviour when passed
+** is defined to accept an argument of type int, its behavior when passed
 ** an integer that falls outside of the range of the unsigned char type
 ** is undefined (and sometimes, "undefined" means segfault). This wrapper
 ** is defined to accept an argument of type char, and always returns 0 for
@@ -123866,7 +126199,7 @@ static int getNextToken(
   rc = sqlite3Fts3OpenTokenizer(pTokenizer, pParse->iLangid, z, n, &pCursor);
   if( rc==SQLITE_OK ){
     const char *zToken;
-    int nToken, iStart, iEnd, iPosition;
+    int nToken = 0, iStart = 0, iEnd = 0, iPosition = 0;
     int nByte;                               /* total space to allocate */
 
     rc = pModule->xNext(pCursor, &zToken, &nToken, &iStart, &iEnd, &iPosition);
@@ -123981,7 +126314,7 @@ static int getNextString(
     int ii;
     for(ii=0; rc==SQLITE_OK; ii++){
       const char *zByte;
-      int nByte, iBegin, iEnd, iPos;
+      int nByte = 0, iBegin = 0, iEnd = 0, iPos = 0;
       rc = pModule->xNext(pCursor, &zByte, &nByte, &iBegin, &iEnd, &iPos);
       if( rc==SQLITE_OK ){
         Fts3PhraseToken *pToken;
@@ -124321,8 +126654,10 @@ static int fts3ExprParse(
         }
         pNot->eType = FTSQUERY_NOT;
         pNot->pRight = p;
+        p->pParent = pNot;
         if( pNotBranch ){
           pNot->pLeft = pNotBranch;
+          pNotBranch->pParent = pNot;
         }
         pNotBranch = pNot;
         p = pPrev;
@@ -124410,6 +126745,7 @@ static int fts3ExprParse(
           pIter = pIter->pLeft;
         }
         pIter->pLeft = pRet;
+        pRet->pParent = pIter;
         pRet = pNotBranch;
       }
     }
@@ -124426,6 +126762,223 @@ exprparse_out:
   return rc;
 }
 
+/*
+** Return SQLITE_ERROR if the maximum depth of the expression tree passed 
+** as the only argument is more than nMaxDepth.
+*/
+static int fts3ExprCheckDepth(Fts3Expr *p, int nMaxDepth){
+  int rc = SQLITE_OK;
+  if( p ){
+    if( nMaxDepth<0 ){ 
+      rc = SQLITE_TOOBIG;
+    }else{
+      rc = fts3ExprCheckDepth(p->pLeft, nMaxDepth-1);
+      if( rc==SQLITE_OK ){
+        rc = fts3ExprCheckDepth(p->pRight, nMaxDepth-1);
+      }
+    }
+  }
+  return rc;
+}
+
+/*
+** This function attempts to transform the expression tree at (*pp) to
+** an equivalent but more balanced form. The tree is modified in place.
+** If successful, SQLITE_OK is returned and (*pp) set to point to the 
+** new root expression node. 
+**
+** nMaxDepth is the maximum allowable depth of the balanced sub-tree.
+**
+** Otherwise, if an error occurs, an SQLite error code is returned and 
+** expression (*pp) freed.
+*/
+static int fts3ExprBalance(Fts3Expr **pp, int nMaxDepth){
+  int rc = SQLITE_OK;             /* Return code */
+  Fts3Expr *pRoot = *pp;          /* Initial root node */
+  Fts3Expr *pFree = 0;            /* List of free nodes. Linked by pParent. */
+  int eType = pRoot->eType;       /* Type of node in this tree */
+
+  if( nMaxDepth==0 ){
+    rc = SQLITE_ERROR;
+  }
+
+  if( rc==SQLITE_OK && (eType==FTSQUERY_AND || eType==FTSQUERY_OR) ){
+    Fts3Expr **apLeaf;
+    apLeaf = (Fts3Expr **)sqlite3_malloc(sizeof(Fts3Expr *) * nMaxDepth);
+    if( 0==apLeaf ){
+      rc = SQLITE_NOMEM;
+    }else{
+      memset(apLeaf, 0, sizeof(Fts3Expr *) * nMaxDepth);
+    }
+
+    if( rc==SQLITE_OK ){
+      int i;
+      Fts3Expr *p;
+
+      /* Set $p to point to the left-most leaf in the tree of eType nodes. */
+      for(p=pRoot; p->eType==eType; p=p->pLeft){
+        assert( p->pParent==0 || p->pParent->pLeft==p );
+        assert( p->pLeft && p->pRight );
+      }
+
+      /* This loop runs once for each leaf in the tree of eType nodes. */
+      while( 1 ){
+        int iLvl;
+        Fts3Expr *pParent = p->pParent;     /* Current parent of p */
+
+        assert( pParent==0 || pParent->pLeft==p );
+        p->pParent = 0;
+        if( pParent ){
+          pParent->pLeft = 0;
+        }else{
+          pRoot = 0;
+        }
+        rc = fts3ExprBalance(&p, nMaxDepth-1);
+        if( rc!=SQLITE_OK ) break;
+
+        for(iLvl=0; p && iLvl<nMaxDepth; iLvl++){
+          if( apLeaf[iLvl]==0 ){
+            apLeaf[iLvl] = p;
+            p = 0;
+          }else{
+            assert( pFree );
+            pFree->pLeft = apLeaf[iLvl];
+            pFree->pRight = p;
+            pFree->pLeft->pParent = pFree;
+            pFree->pRight->pParent = pFree;
+
+            p = pFree;
+            pFree = pFree->pParent;
+            p->pParent = 0;
+            apLeaf[iLvl] = 0;
+          }
+        }
+        if( p ){
+          sqlite3Fts3ExprFree(p);
+          rc = SQLITE_TOOBIG;
+          break;
+        }
+
+        /* If that was the last leaf node, break out of the loop */
+        if( pParent==0 ) break;
+
+        /* Set $p to point to the next leaf in the tree of eType nodes */
+        for(p=pParent->pRight; p->eType==eType; p=p->pLeft);
+
+        /* Remove pParent from the original tree. */
+        assert( pParent->pParent==0 || pParent->pParent->pLeft==pParent );
+        pParent->pRight->pParent = pParent->pParent;
+        if( pParent->pParent ){
+          pParent->pParent->pLeft = pParent->pRight;
+        }else{
+          assert( pParent==pRoot );
+          pRoot = pParent->pRight;
+        }
+
+        /* Link pParent into the free node list. It will be used as an
+        ** internal node of the new tree.  */
+        pParent->pParent = pFree;
+        pFree = pParent;
+      }
+
+      if( rc==SQLITE_OK ){
+        p = 0;
+        for(i=0; i<nMaxDepth; i++){
+          if( apLeaf[i] ){
+            if( p==0 ){
+              p = apLeaf[i];
+              p->pParent = 0;
+            }else{
+              assert( pFree!=0 );
+              pFree->pRight = p;
+              pFree->pLeft = apLeaf[i];
+              pFree->pLeft->pParent = pFree;
+              pFree->pRight->pParent = pFree;
+
+              p = pFree;
+              pFree = pFree->pParent;
+              p->pParent = 0;
+            }
+          }
+        }
+        pRoot = p;
+      }else{
+        /* An error occurred. Delete the contents of the apLeaf[] array 
+        ** and pFree list. Everything else is cleaned up by the call to
+        ** sqlite3Fts3ExprFree(pRoot) below.  */
+        Fts3Expr *pDel;
+        for(i=0; i<nMaxDepth; i++){
+          sqlite3Fts3ExprFree(apLeaf[i]);
+        }
+        while( (pDel=pFree)!=0 ){
+          pFree = pDel->pParent;
+          sqlite3_free(pDel);
+        }
+      }
+
+      assert( pFree==0 );
+      sqlite3_free( apLeaf );
+    }
+  }
+
+  if( rc!=SQLITE_OK ){
+    sqlite3Fts3ExprFree(pRoot);
+    pRoot = 0;
+  }
+  *pp = pRoot;
+  return rc;
+}
+
+/*
+** This function is similar to sqlite3Fts3ExprParse(), with the following
+** differences:
+**
+**   1. It does not do expression rebalancing.
+**   2. It does not check that the expression does not exceed the 
+**      maximum allowable depth.
+**   3. Even if it fails, *ppExpr may still be set to point to an 
+**      expression tree. It should be deleted using sqlite3Fts3ExprFree()
+**      in this case.
+*/
+static int fts3ExprParseUnbalanced(
+  sqlite3_tokenizer *pTokenizer,      /* Tokenizer module */
+  int iLangid,                        /* Language id for tokenizer */
+  char **azCol,                       /* Array of column names for fts3 table */
+  int bFts4,                          /* True to allow FTS4-only syntax */
+  int nCol,                           /* Number of entries in azCol[] */
+  int iDefaultCol,                    /* Default column to query */
+  const char *z, int n,               /* Text of MATCH query */
+  Fts3Expr **ppExpr                   /* OUT: Parsed query structure */
+){
+  int nParsed;
+  int rc;
+  ParseContext sParse;
+
+  memset(&sParse, 0, sizeof(ParseContext));
+  sParse.pTokenizer = pTokenizer;
+  sParse.iLangid = iLangid;
+  sParse.azCol = (const char **)azCol;
+  sParse.nCol = nCol;
+  sParse.iDefaultCol = iDefaultCol;
+  sParse.bFts4 = bFts4;
+  if( z==0 ){
+    *ppExpr = 0;
+    return SQLITE_OK;
+  }
+  if( n<0 ){
+    n = (int)strlen(z);
+  }
+  rc = fts3ExprParse(&sParse, z, n, ppExpr, &nParsed);
+  assert( rc==SQLITE_OK || *ppExpr==0 );
+
+  /* Check for mismatched parenthesis */
+  if( rc==SQLITE_OK && sParse.nNest ){
+    rc = SQLITE_ERROR;
+  }
+  
+  return rc;
+}
+
 /*
 ** Parameters z and n contain a pointer to and length of a buffer containing
 ** an fts3 query expression, respectively. This function attempts to parse the
@@ -124458,49 +127011,74 @@ SQLITE_PRIVATE int sqlite3Fts3ExprParse(
   int nCol,                           /* Number of entries in azCol[] */
   int iDefaultCol,                    /* Default column to query */
   const char *z, int n,               /* Text of MATCH query */
-  Fts3Expr **ppExpr                   /* OUT: Parsed query structure */
+  Fts3Expr **ppExpr,                  /* OUT: Parsed query structure */
+  char **pzErr                        /* OUT: Error message (sqlite3_malloc) */
 ){
-  int nParsed;
-  int rc;
-  ParseContext sParse;
-
-  memset(&sParse, 0, sizeof(ParseContext));
-  sParse.pTokenizer = pTokenizer;
-  sParse.iLangid = iLangid;
-  sParse.azCol = (const char **)azCol;
-  sParse.nCol = nCol;
-  sParse.iDefaultCol = iDefaultCol;
-  sParse.bFts4 = bFts4;
-  if( z==0 ){
-    *ppExpr = 0;
-    return SQLITE_OK;
+  int rc = fts3ExprParseUnbalanced(
+      pTokenizer, iLangid, azCol, bFts4, nCol, iDefaultCol, z, n, ppExpr
+  );
+  
+  /* Rebalance the expression. And check that its depth does not exceed
+  ** SQLITE_FTS3_MAX_EXPR_DEPTH.  */
+  if( rc==SQLITE_OK && *ppExpr ){
+    rc = fts3ExprBalance(ppExpr, SQLITE_FTS3_MAX_EXPR_DEPTH);
+    if( rc==SQLITE_OK ){
+      rc = fts3ExprCheckDepth(*ppExpr, SQLITE_FTS3_MAX_EXPR_DEPTH);
+    }
   }
-  if( n<0 ){
-    n = (int)strlen(z);
-  }
-  rc = fts3ExprParse(&sParse, z, n, ppExpr, &nParsed);
 
-  /* Check for mismatched parenthesis */
-  if( rc==SQLITE_OK && sParse.nNest ){
-    rc = SQLITE_ERROR;
+  if( rc!=SQLITE_OK ){
     sqlite3Fts3ExprFree(*ppExpr);
     *ppExpr = 0;
+    if( rc==SQLITE_TOOBIG ){
+      *pzErr = sqlite3_mprintf(
+          "FTS expression tree is too large (maximum depth %d)", 
+          SQLITE_FTS3_MAX_EXPR_DEPTH
+      );
+      rc = SQLITE_ERROR;
+    }else if( rc==SQLITE_ERROR ){
+      *pzErr = sqlite3_mprintf("malformed MATCH expression: [%s]", z);
+    }
   }
 
   return rc;
 }
 
 /*
-** Free a parsed fts3 query expression allocated by sqlite3Fts3ExprParse().
+** Free a single node of an expression tree.
 */
-SQLITE_PRIVATE void sqlite3Fts3ExprFree(Fts3Expr *p){
-  if( p ){
-    assert( p->eType==FTSQUERY_PHRASE || p->pPhrase==0 );
-    sqlite3Fts3ExprFree(p->pLeft);
-    sqlite3Fts3ExprFree(p->pRight);
-    sqlite3Fts3EvalPhraseCleanup(p->pPhrase);
-    sqlite3_free(p->aMI);
-    sqlite3_free(p);
+static void fts3FreeExprNode(Fts3Expr *p){
+  assert( p->eType==FTSQUERY_PHRASE || p->pPhrase==0 );
+  sqlite3Fts3EvalPhraseCleanup(p->pPhrase);
+  sqlite3_free(p->aMI);
+  sqlite3_free(p);
+}
+
+/*
+** Free a parsed fts3 query expression allocated by sqlite3Fts3ExprParse().
+**
+** This function would be simpler if it recursively called itself. But
+** that would mean passing a sufficiently large expression to ExprParse()
+** could cause a stack overflow.
+*/
+SQLITE_PRIVATE void sqlite3Fts3ExprFree(Fts3Expr *pDel){
+  Fts3Expr *p;
+  assert( pDel==0 || pDel->pParent==0 );
+  for(p=pDel; p && (p->pLeft||p->pRight); p=(p->pLeft ? p->pLeft : p->pRight)){
+    assert( p->pParent==0 || p==p->pParent->pRight || p==p->pParent->pLeft );
+  }
+  while( p ){
+    Fts3Expr *pParent = p->pParent;
+    fts3FreeExprNode(p);
+    if( pParent && p==pParent->pLeft && pParent->pRight ){
+      p = pParent->pRight;
+      while( p && (p->pLeft || p->pRight) ){
+        assert( p==p->pParent->pRight || p==p->pParent->pLeft );
+        p = (p->pLeft ? p->pLeft : p->pRight);
+      }
+    }else{
+      p = pParent;
+    }
   }
 }
 
@@ -124552,6 +127130,9 @@ static int queryTestTokenizer(
 ** the returned expression text and then freed using sqlite3_free().
 */
 static char *exprToString(Fts3Expr *pExpr, char *zBuf){
+  if( pExpr==0 ){
+    return sqlite3_mprintf("");
+  }
   switch( pExpr->eType ){
     case FTSQUERY_PHRASE: {
       Fts3Phrase *pPhrase = pExpr->pPhrase;
@@ -124659,10 +127240,21 @@ static void fts3ExprTest(
     azCol[ii] = (char *)sqlite3_value_text(argv[ii+2]);
   }
 
-  rc = sqlite3Fts3ExprParse(
-      pTokenizer, 0, azCol, 0, nCol, nCol, zExpr, nExpr, &pExpr
-  );
+  if( sqlite3_user_data(context) ){
+    char *zDummy = 0;
+    rc = sqlite3Fts3ExprParse(
+        pTokenizer, 0, azCol, 0, nCol, nCol, zExpr, nExpr, &pExpr, &zDummy
+    );
+    assert( rc==SQLITE_OK || pExpr==0 );
+    sqlite3_free(zDummy);
+  }else{
+    rc = fts3ExprParseUnbalanced(
+        pTokenizer, 0, azCol, 0, nCol, nCol, zExpr, nExpr, &pExpr
+    );
+  }
+
   if( rc!=SQLITE_OK && rc!=SQLITE_NOMEM ){
+    sqlite3Fts3ExprFree(pExpr);
     sqlite3_result_error(context, "Error parsing expression", -1);
   }else if( rc==SQLITE_NOMEM || !(zBuf = exprToString(pExpr, 0)) ){
     sqlite3_result_error_nomem(context);
@@ -124685,9 +127277,15 @@ exprtest_out:
 ** with database connection db. 
 */
 SQLITE_PRIVATE int sqlite3Fts3ExprInitTestInterface(sqlite3* db){
-  return sqlite3_create_function(
+  int rc = sqlite3_create_function(
       db, "fts3_exprtest", -1, SQLITE_UTF8, 0, fts3ExprTest, 0, 0
   );
+  if( rc==SQLITE_OK ){
+    rc = sqlite3_create_function(db, "fts3_exprtest_rebalance", 
+        -1, SQLITE_UTF8, (void *)1, fts3ExprTest, 0, 0
+    );
+  }
+  return rc;
 }
 
 #endif
@@ -125930,7 +128528,7 @@ SQLITE_PRIVATE int sqlite3Fts3InitTokenizer(
 
 #ifdef SQLITE_TEST
 
-/* #include <tcl.h> */
+#include <tcl.h>
 /* #include <string.h> */
 
 /*
@@ -125978,10 +128576,10 @@ static void testFunc(
   const char *azArg[64];
 
   const char *zToken;
-  int nToken;
-  int iStart;
-  int iEnd;
-  int iPos;
+  int nToken = 0;
+  int iStart = 0;
+  int iEnd = 0;
+  int iPos = 0;
   int i;
 
   Tcl_Obj *pRet;
@@ -126155,7 +128753,7 @@ static void intTestFunc(
 /*
 ** Set up SQL objects in database db used to access the contents of
 ** the hash table pointed to by argument pHash. The hash table must
-** been initialised to use string keys, and to take a private copy 
+** been initialized to use string keys, and to take a private copy 
 ** of the key when a value is inserted. i.e. by a call similar to:
 **
 **    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
@@ -126450,6 +129048,462 @@ SQLITE_PRIVATE void sqlite3Fts3SimpleTokenizerModule(
 #endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
 
 /************** End of fts3_tokenizer1.c *************************************/
+/************** Begin file fts3_tokenize_vtab.c ******************************/
+/*
+** 2013 Apr 22
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This file contains code for the "fts3tokenize" virtual table module.
+** An fts3tokenize virtual table is created as follows:
+**
+**   CREATE VIRTUAL TABLE <tbl> USING fts3tokenize(
+**       <tokenizer-name>, <arg-1>, ...
+**   );
+**
+** The table created has the following schema:
+**
+**   CREATE TABLE <tbl>(input, token, start, end, position)
+**
+** When queried, the query must include a WHERE clause of type:
+**
+**   input = <string>
+**
+** The virtual table module tokenizes this <string>, using the FTS3 
+** tokenizer specified by the arguments to the CREATE VIRTUAL TABLE 
+** statement and returns one row for each token in the result. With
+** fields set as follows:
+**
+**   input:   Always set to a copy of <string>
+**   token:   A token from the input.
+**   start:   Byte offset of the token within the input <string>.
+**   end:     Byte offset of the byte immediately following the end of the
+**            token within the input string.
+**   pos:     Token offset of token within input.
+**
+*/
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
+
+/* #include <string.h> */
+/* #include <assert.h> */
+
+typedef struct Fts3tokTable Fts3tokTable;
+typedef struct Fts3tokCursor Fts3tokCursor;
+
+/*
+** Virtual table structure.
+*/
+struct Fts3tokTable {
+  sqlite3_vtab base;              /* Base class used by SQLite core */
+  const sqlite3_tokenizer_module *pMod;
+  sqlite3_tokenizer *pTok;
+};
+
+/*
+** Virtual table cursor structure.
+*/
+struct Fts3tokCursor {
+  sqlite3_vtab_cursor base;       /* Base class used by SQLite core */
+  char *zInput;                   /* Input string */
+  sqlite3_tokenizer_cursor *pCsr; /* Cursor to iterate through zInput */
+  int iRowid;                     /* Current 'rowid' value */
+  const char *zToken;             /* Current 'token' value */
+  int nToken;                     /* Size of zToken in bytes */
+  int iStart;                     /* Current 'start' value */
+  int iEnd;                       /* Current 'end' value */
+  int iPos;                       /* Current 'pos' value */
+};
+
+/*
+** Query FTS for the tokenizer implementation named zName.
+*/
+static int fts3tokQueryTokenizer(
+  Fts3Hash *pHash,
+  const char *zName,
+  const sqlite3_tokenizer_module **pp,
+  char **pzErr
+){
+  sqlite3_tokenizer_module *p;
+  int nName = (int)strlen(zName);
+
+  p = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zName, nName+1);
+  if( !p ){
+    *pzErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
+    return SQLITE_ERROR;
+  }
+
+  *pp = p;
+  return SQLITE_OK;
+}
+
+/*
+** The second argument, argv[], is an array of pointers to nul-terminated
+** strings. This function makes a copy of the array and strings into a 
+** single block of memory. It then dequotes any of the strings that appear
+** to be quoted.
+**
+** If successful, output parameter *pazDequote is set to point at the
+** array of dequoted strings and SQLITE_OK is returned. The caller is
+** responsible for eventually calling sqlite3_free() to free the array
+** in this case. Or, if an error occurs, an SQLite error code is returned.
+** The final value of *pazDequote is undefined in this case.
+*/
+static int fts3tokDequoteArray(
+  int argc,                       /* Number of elements in argv[] */
+  const char * const *argv,       /* Input array */
+  char ***pazDequote              /* Output array */
+){
+  int rc = SQLITE_OK;             /* Return code */
+  if( argc==0 ){
+    *pazDequote = 0;
+  }else{
+    int i;
+    int nByte = 0;
+    char **azDequote;
+
+    for(i=0; i<argc; i++){
+      nByte += (int)(strlen(argv[i]) + 1);
+    }
+
+    *pazDequote = azDequote = sqlite3_malloc(sizeof(char *)*argc + nByte);
+    if( azDequote==0 ){
+      rc = SQLITE_NOMEM;
+    }else{
+      char *pSpace = (char *)&azDequote[argc];
+      for(i=0; i<argc; i++){
+        int n = (int)strlen(argv[i]);
+        azDequote[i] = pSpace;
+        memcpy(pSpace, argv[i], n+1);
+        sqlite3Fts3Dequote(pSpace);
+        pSpace += (n+1);
+      }
+    }
+  }
+
+  return rc;
+}
+
+/*
+** Schema of the tokenizer table.
+*/
+#define FTS3_TOK_SCHEMA "CREATE TABLE x(input, token, start, end, position)"
+
+/*
+** This function does all the work for both the xConnect and xCreate methods.
+** These tables have no persistent representation of their own, so xConnect
+** and xCreate are identical operations.
+**
+**   argv[0]: module name
+**   argv[1]: database name 
+**   argv[2]: table name
+**   argv[3]: first argument (tokenizer name)
+*/
+static int fts3tokConnectMethod(
+  sqlite3 *db,                    /* Database connection */
+  void *pHash,                    /* Hash table of tokenizers */
+  int argc,                       /* Number of elements in argv array */
+  const char * const *argv,       /* xCreate/xConnect argument array */
+  sqlite3_vtab **ppVtab,          /* OUT: New sqlite3_vtab object */
+  char **pzErr                    /* OUT: sqlite3_malloc'd error message */
+){
+  Fts3tokTable *pTab;
+  const sqlite3_tokenizer_module *pMod = 0;
+  sqlite3_tokenizer *pTok = 0;
+  int rc;
+  char **azDequote = 0;
+  int nDequote;
+
+  rc = sqlite3_declare_vtab(db, FTS3_TOK_SCHEMA);
+  if( rc!=SQLITE_OK ) return rc;
+
+  nDequote = argc-3;
+  rc = fts3tokDequoteArray(nDequote, &argv[3], &azDequote);
+
+  if( rc==SQLITE_OK ){
+    const char *zModule;
+    if( nDequote<1 ){
+      zModule = "simple";
+    }else{
+      zModule = azDequote[0];
+    }
+    rc = fts3tokQueryTokenizer((Fts3Hash*)pHash, zModule, &pMod, pzErr);
+  }
+
+  assert( (rc==SQLITE_OK)==(pMod!=0) );
+  if( rc==SQLITE_OK ){
+    const char * const *azArg = (const char * const *)&azDequote[1];
+    rc = pMod->xCreate((nDequote>1 ? nDequote-1 : 0), azArg, &pTok);
+  }
+
+  if( rc==SQLITE_OK ){
+    pTab = (Fts3tokTable *)sqlite3_malloc(sizeof(Fts3tokTable));
+    if( pTab==0 ){
+      rc = SQLITE_NOMEM;
+    }
+  }
+
+  if( rc==SQLITE_OK ){
+    memset(pTab, 0, sizeof(Fts3tokTable));
+    pTab->pMod = pMod;
+    pTab->pTok = pTok;
+    *ppVtab = &pTab->base;
+  }else{
+    if( pTok ){
+      pMod->xDestroy(pTok);
+    }
+  }
+
+  sqlite3_free(azDequote);
+  return rc;
+}
+
+/*
+** This function does the work for both the xDisconnect and xDestroy methods.
+** These tables have no persistent representation of their own, so xDisconnect
+** and xDestroy are identical operations.
+*/
+static int fts3tokDisconnectMethod(sqlite3_vtab *pVtab){
+  Fts3tokTable *pTab = (Fts3tokTable *)pVtab;
+
+  pTab->pMod->xDestroy(pTab->pTok);
+  sqlite3_free(pTab);
+  return SQLITE_OK;
+}
+
+/*
+** xBestIndex - Analyze a WHERE and ORDER BY clause.
+*/
+static int fts3tokBestIndexMethod(
+  sqlite3_vtab *pVTab, 
+  sqlite3_index_info *pInfo
+){
+  int i;
+  UNUSED_PARAMETER(pVTab);
+
+  for(i=0; i<pInfo->nConstraint; i++){
+    if( pInfo->aConstraint[i].usable 
+     && pInfo->aConstraint[i].iColumn==0 
+     && pInfo->aConstraint[i].op==SQLITE_INDEX_CONSTRAINT_EQ 
+    ){
+      pInfo->idxNum = 1;
+      pInfo->aConstraintUsage[i].argvIndex = 1;
+      pInfo->aConstraintUsage[i].omit = 1;
+      pInfo->estimatedCost = 1;
+      return SQLITE_OK;
+    }
+  }
+
+  pInfo->idxNum = 0;
+  assert( pInfo->estimatedCost>1000000.0 );
+
+  return SQLITE_OK;
+}
+
+/*
+** xOpen - Open a cursor.
+*/
+static int fts3tokOpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
+  Fts3tokCursor *pCsr;
+  UNUSED_PARAMETER(pVTab);
+
+  pCsr = (Fts3tokCursor *)sqlite3_malloc(sizeof(Fts3tokCursor));
+  if( pCsr==0 ){
+    return SQLITE_NOMEM;
+  }
+  memset(pCsr, 0, sizeof(Fts3tokCursor));
+
+  *ppCsr = (sqlite3_vtab_cursor *)pCsr;
+  return SQLITE_OK;
+}
+
+/*
+** Reset the tokenizer cursor passed as the only argument. As if it had
+** just been returned by fts3tokOpenMethod().
+*/
+static void fts3tokResetCursor(Fts3tokCursor *pCsr){
+  if( pCsr->pCsr ){
+    Fts3tokTable *pTab = (Fts3tokTable *)(pCsr->base.pVtab);
+    pTab->pMod->xClose(pCsr->pCsr);
+    pCsr->pCsr = 0;
+  }
+  sqlite3_free(pCsr->zInput);
+  pCsr->zInput = 0;
+  pCsr->zToken = 0;
+  pCsr->nToken = 0;
+  pCsr->iStart = 0;
+  pCsr->iEnd = 0;
+  pCsr->iPos = 0;
+  pCsr->iRowid = 0;
+}
+
+/*
+** xClose - Close a cursor.
+*/
+static int fts3tokCloseMethod(sqlite3_vtab_cursor *pCursor){
+  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
+
+  fts3tokResetCursor(pCsr);
+  sqlite3_free(pCsr);
+  return SQLITE_OK;
+}
+
+/*
+** xNext - Advance the cursor to the next row, if any.
+*/
+static int fts3tokNextMethod(sqlite3_vtab_cursor *pCursor){
+  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
+  Fts3tokTable *pTab = (Fts3tokTable *)(pCursor->pVtab);
+  int rc;                         /* Return code */
+
+  pCsr->iRowid++;
+  rc = pTab->pMod->xNext(pCsr->pCsr,
+      &pCsr->zToken, &pCsr->nToken,
+      &pCsr->iStart, &pCsr->iEnd, &pCsr->iPos
+  );
+
+  if( rc!=SQLITE_OK ){
+    fts3tokResetCursor(pCsr);
+    if( rc==SQLITE_DONE ) rc = SQLITE_OK;
+  }
+
+  return rc;
+}
+
+/*
+** xFilter - Initialize a cursor to point at the start of its data.
+*/
+static int fts3tokFilterMethod(
+  sqlite3_vtab_cursor *pCursor,   /* The cursor used for this query */
+  int idxNum,                     /* Strategy index */
+  const char *idxStr,             /* Unused */
+  int nVal,                       /* Number of elements in apVal */
+  sqlite3_value **apVal           /* Arguments for the indexing scheme */
+){
+  int rc = SQLITE_ERROR;
+  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
+  Fts3tokTable *pTab = (Fts3tokTable *)(pCursor->pVtab);
+  UNUSED_PARAMETER(idxStr);
+  UNUSED_PARAMETER(nVal);
+
+  fts3tokResetCursor(pCsr);
+  if( idxNum==1 ){
+    const char *zByte = (const char *)sqlite3_value_text(apVal[0]);
+    int nByte = sqlite3_value_bytes(apVal[0]);
+    pCsr->zInput = sqlite3_malloc(nByte+1);
+    if( pCsr->zInput==0 ){
+      rc = SQLITE_NOMEM;
+    }else{
+      memcpy(pCsr->zInput, zByte, nByte);
+      pCsr->zInput[nByte] = 0;
+      rc = pTab->pMod->xOpen(pTab->pTok, pCsr->zInput, nByte, &pCsr->pCsr);
+      if( rc==SQLITE_OK ){
+        pCsr->pCsr->pTokenizer = pTab->pTok;
+      }
+    }
+  }
+
+  if( rc!=SQLITE_OK ) return rc;
+  return fts3tokNextMethod(pCursor);
+}
+
+/*
+** xEof - Return true if the cursor is at EOF, or false otherwise.
+*/
+static int fts3tokEofMethod(sqlite3_vtab_cursor *pCursor){
+  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
+  return (pCsr->zToken==0);
+}
+
+/*
+** xColumn - Return a column value.
+*/
+static int fts3tokColumnMethod(
+  sqlite3_vtab_cursor *pCursor,   /* Cursor to retrieve value from */
+  sqlite3_context *pCtx,          /* Context for sqlite3_result_xxx() calls */
+  int iCol                        /* Index of column to read value from */
+){
+  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
+
+  /* CREATE TABLE x(input, token, start, end, position) */
+  switch( iCol ){
+    case 0:
+      sqlite3_result_text(pCtx, pCsr->zInput, -1, SQLITE_TRANSIENT);
+      break;
+    case 1:
+      sqlite3_result_text(pCtx, pCsr->zToken, pCsr->nToken, SQLITE_TRANSIENT);
+      break;
+    case 2:
+      sqlite3_result_int(pCtx, pCsr->iStart);
+      break;
+    case 3:
+      sqlite3_result_int(pCtx, pCsr->iEnd);
+      break;
+    default:
+      assert( iCol==4 );
+      sqlite3_result_int(pCtx, pCsr->iPos);
+      break;
+  }
+  return SQLITE_OK;
+}
+
+/*
+** xRowid - Return the current rowid for the cursor.
+*/
+static int fts3tokRowidMethod(
+  sqlite3_vtab_cursor *pCursor,   /* Cursor to retrieve value from */
+  sqlite_int64 *pRowid            /* OUT: Rowid value */
+){
+  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
+  *pRowid = (sqlite3_int64)pCsr->iRowid;
+  return SQLITE_OK;
+}
+
+/*
+** Register the fts3tok module with database connection db. Return SQLITE_OK
+** if successful or an error code if sqlite3_create_module() fails.
+*/
+SQLITE_PRIVATE int sqlite3Fts3InitTok(sqlite3 *db, Fts3Hash *pHash){
+  static const sqlite3_module fts3tok_module = {
+     0,                           /* iVersion      */
+     fts3tokConnectMethod,        /* xCreate       */
+     fts3tokConnectMethod,        /* xConnect      */
+     fts3tokBestIndexMethod,      /* xBestIndex    */
+     fts3tokDisconnectMethod,     /* xDisconnect   */
+     fts3tokDisconnectMethod,     /* xDestroy      */
+     fts3tokOpenMethod,           /* xOpen         */
+     fts3tokCloseMethod,          /* xClose        */
+     fts3tokFilterMethod,         /* xFilter       */
+     fts3tokNextMethod,           /* xNext         */
+     fts3tokEofMethod,            /* xEof          */
+     fts3tokColumnMethod,         /* xColumn       */
+     fts3tokRowidMethod,          /* xRowid        */
+     0,                           /* xUpdate       */
+     0,                           /* xBegin        */
+     0,                           /* xSync         */
+     0,                           /* xCommit       */
+     0,                           /* xRollback     */
+     0,                           /* xFindFunction */
+     0,                           /* xRename       */
+     0,                           /* xSavepoint    */
+     0,                           /* xRelease      */
+     0                            /* xRollbackTo   */
+  };
+  int rc;                         /* Return code */
+
+  rc = sqlite3_create_module(db, "fts3tokenize", &fts3tok_module, (void*)pHash);
+  return rc;
+}
+
+#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
+
+/************** End of fts3_tokenize_vtab.c **********************************/
 /************** Begin file fts3_write.c **************************************/
 /*
 ** 2009 Oct 23
@@ -126941,37 +129995,30 @@ static void fts3SqlExec(
 
 
 /*
-** This function ensures that the caller has obtained a shared-cache
-** table-lock on the %_content table. This is required before reading
-** data from the fts3 table. If this lock is not acquired first, then
-** the caller may end up holding read-locks on the %_segments and %_segdir
-** tables, but no read-lock on the %_content table. If this happens 
-** a second connection will be able to write to the fts3 table, but
-** attempting to commit those writes might return SQLITE_LOCKED or
-** SQLITE_LOCKED_SHAREDCACHE (because the commit attempts to obtain 
-** write-locks on the %_segments and %_segdir ** tables). 
+** This function ensures that the caller has obtained an exclusive 
+** shared-cache table-lock on the %_segdir table. This is required before 
+** writing data to the fts3 table. If this lock is not acquired first, then
+** the caller may end up attempting to take this lock as part of committing
+** a transaction, causing SQLite to return SQLITE_LOCKED or 
+** LOCKED_SHAREDCACHEto a COMMIT command.
 **
-** We try to avoid this because if FTS3 returns any error when committing
-** a transaction, the whole transaction will be rolled back. And this is
-** not what users expect when they get SQLITE_LOCKED_SHAREDCACHE. It can
-** still happen if the user reads data directly from the %_segments or
-** %_segdir tables instead of going through FTS3 though.
-**
-** This reasoning does not apply to a content=xxx table.
+** It is best to avoid this because if FTS3 returns any error when 
+** committing a transaction, the whole transaction will be rolled back. 
+** And this is not what users expect when they get SQLITE_LOCKED_SHAREDCACHE. 
+** It can still happen if the user locks the underlying tables directly 
+** instead of accessing them via FTS.
 */
-SQLITE_PRIVATE int sqlite3Fts3ReadLock(Fts3Table *p){
-  int rc;                         /* Return code */
-  sqlite3_stmt *pStmt;            /* Statement used to obtain lock */
-
-  if( p->zContentTbl==0 ){
-    rc = fts3SqlStmt(p, SQL_SELECT_CONTENT_BY_ROWID, &pStmt, 0);
+static int fts3Writelock(Fts3Table *p){
+  int rc = SQLITE_OK;
+  
+  if( p->nPendingData==0 ){
+    sqlite3_stmt *pStmt;
+    rc = fts3SqlStmt(p, SQL_DELETE_SEGDIR_LEVEL, &pStmt, 0);
     if( rc==SQLITE_OK ){
       sqlite3_bind_null(pStmt, 1);
       sqlite3_step(pStmt);
       rc = sqlite3_reset(pStmt);
     }
-  }else{
-    rc = SQLITE_OK;
   }
 
   return rc;
@@ -127228,16 +130275,16 @@ static int fts3PendingTermsAdd(
   int iLangid,                    /* Language id to use */
   const char *zText,              /* Text of document to be inserted */
   int iCol,                       /* Column into which text is being inserted */
-  u32 *pnWord                     /* OUT: Number of tokens inserted */
+  u32 *pnWord                     /* IN/OUT: Incr. by number tokens inserted */
 ){
   int rc;
-  int iStart;
-  int iEnd;
-  int iPos;
+  int iStart = 0;
+  int iEnd = 0;
+  int iPos = 0;
   int nWord = 0;
 
   char const *zToken;
-  int nToken;
+  int nToken = 0;
 
   sqlite3_tokenizer *pTokenizer = p->pTokenizer;
   sqlite3_tokenizer_module const *pModule = pTokenizer->pModule;
@@ -127292,7 +130339,7 @@ static int fts3PendingTermsAdd(
   }
 
   pModule->xClose(pCsr);
-  *pnWord = nWord;
+  *pnWord += nWord;
   return (rc==SQLITE_DONE ? SQLITE_OK : rc);
 }
 
@@ -127359,12 +130406,15 @@ static int fts3InsertTerms(
 ){
   int i;                          /* Iterator variable */
   for(i=2; i<p->nColumn+2; i++){
-    const char *zText = (const char *)sqlite3_value_text(apVal[i]);
-    int rc = fts3PendingTermsAdd(p, iLangid, zText, i-2, &aSz[i-2]);
-    if( rc!=SQLITE_OK ){
-      return rc;
+    int iCol = i-2;
+    if( p->abNotindexed[iCol]==0 ){
+      const char *zText = (const char *)sqlite3_value_text(apVal[i]);
+      int rc = fts3PendingTermsAdd(p, iLangid, zText, iCol, &aSz[iCol]);
+      if( rc!=SQLITE_OK ){
+        return rc;
+      }
+      aSz[p->nColumn] += sqlite3_value_bytes(apVal[i]);
     }
-    aSz[p->nColumn] += sqlite3_value_bytes(apVal[i]);
   }
   return SQLITE_OK;
 }
@@ -127496,11 +130546,13 @@ static void fts3DeleteTerms(
   int *pRC,               /* Result code */
   Fts3Table *p,           /* The FTS table to delete from */
   sqlite3_value *pRowid,  /* The docid to be deleted */
-  u32 *aSz                /* Sizes of deleted document written here */
+  u32 *aSz,               /* Sizes of deleted document written here */
+  int *pbFound            /* OUT: Set to true if row really does exist */
 ){
   int rc;
   sqlite3_stmt *pSelect;
 
+  assert( *pbFound==0 );
   if( *pRC ) return;
   rc = fts3SqlStmt(p, SQL_SELECT_CONTENT_BY_ROWID, &pSelect, &pRowid);
   if( rc==SQLITE_OK ){
@@ -127509,15 +130561,19 @@ static void fts3DeleteTerms(
       int iLangid = langidFromSelect(p, pSelect);
       rc = fts3PendingTermsDocid(p, iLangid, sqlite3_column_int64(pSelect, 0));
       for(i=1; rc==SQLITE_OK && i<=p->nColumn; i++){
-        const char *zText = (const char *)sqlite3_column_text(pSelect, i);
-        rc = fts3PendingTermsAdd(p, iLangid, zText, -1, &aSz[i-1]);
-        aSz[p->nColumn] += sqlite3_column_bytes(pSelect, i);
+        int iCol = i-1;
+        if( p->abNotindexed[iCol]==0 ){
+          const char *zText = (const char *)sqlite3_column_text(pSelect, i);
+          rc = fts3PendingTermsAdd(p, iLangid, zText, -1, &aSz[iCol]);
+          aSz[p->nColumn] += sqlite3_column_bytes(pSelect, i);
+        }
       }
       if( rc!=SQLITE_OK ){
         sqlite3_reset(pSelect);
         *pRC = rc;
         return;
       }
+      *pbFound = 1;
     }
     rc = sqlite3_reset(pSelect);
   }else{
@@ -127911,7 +130967,7 @@ static int fts3SegReaderNextDocid(
       /* The following line of code (and the "p++" below the while() loop) is
       ** normally all that is required to move pointer p to the desired 
       ** position. The exception is if this node is being loaded from disk
-      ** incrementally and pointer "p" now points to the first byte passed
+      ** incrementally and pointer "p" now points to the first byte past
       ** the populated part of pReader->aNode[].
       */
       while( *p | c ) c = *p++ & 0x80;
@@ -127931,6 +130987,7 @@ static int fts3SegReaderNextDocid(
       *pnOffsetList = (int)(p - pReader->pOffsetList - 1);
     }
 
+    /* List may have been edited in place by fts3EvalNearTrim() */
     while( p<pEnd && *p==0 ) p++;
   
     /* If there are no more entries in the doclist, set pOffsetList to
@@ -128946,9 +132003,13 @@ static int fts3DeleteSegdir(
 **
 ** If there are no entries in the input position list for column iCol, then
 ** *pnList is set to zero before returning.
+**
+** If parameter bZero is non-zero, then any part of the input list following
+** the end of the output list is zeroed before returning.
 */
 static void fts3ColumnFilter(
   int iCol,                       /* Column to filter on */
+  int bZero,                      /* Zero out anything following *ppList */
   char **ppList,                  /* IN/OUT: Pointer to position list */
   int *pnList                     /* IN/OUT: Size of buffer *ppList in bytes */
 ){
@@ -128977,6 +132038,9 @@ static void fts3ColumnFilter(
     p += sqlite3Fts3GetVarint32(p, &iCurrent);
   }
 
+  if( bZero && &pList[nList]!=pEnd ){
+    memset(&pList[nList], 0, pEnd - &pList[nList]);
+  }
   *ppList = pList;
   *pnList = nList;
 }
@@ -129050,19 +132114,19 @@ SQLITE_PRIVATE int sqlite3Fts3MsrIncrNext(
       if( rc!=SQLITE_OK ) return rc;
       fts3SegReaderSort(pMsr->apSegment, nMerge, j, xCmp);
 
+      if( nList>0 && fts3SegReaderIsPending(apSegment[0]) ){
+        rc = fts3MsrBufferData(pMsr, pList, nList+1);
+        if( rc!=SQLITE_OK ) return rc;
+        assert( (pMsr->aBuffer[nList] & 0xFE)==0x00 );
+        pList = pMsr->aBuffer;
+      }
+
       if( pMsr->iColFilter>=0 ){
-        fts3ColumnFilter(pMsr->iColFilter, &pList, &nList);
+        fts3ColumnFilter(pMsr->iColFilter, 1, &pList, &nList);
       }
 
       if( nList>0 ){
-        if( fts3SegReaderIsPending(apSegment[0]) ){
-          rc = fts3MsrBufferData(pMsr, pList, nList+1);
-          if( rc!=SQLITE_OK ) return rc;
-          *paPoslist = pMsr->aBuffer;
-          assert( (pMsr->aBuffer[nList] & 0xFE)==0x00 );
-        }else{
-          *paPoslist = pList;
-        }
+        *paPoslist = pList;
         *piDocid = iDocid;
         *pnPoslist = nList;
         break;
@@ -129290,8 +132354,8 @@ SQLITE_PRIVATE int sqlite3Fts3SegReaderStep(
       fts3SegReaderSort(apSegment, nMerge, nMerge, xCmp);
       while( apSegment[0]->pOffsetList ){
         int j;                    /* Number of segments that share a docid */
-        char *pList;
-        int nList;
+        char *pList = 0;
+        int nList = 0;
         int nByte;
         sqlite3_int64 iDocid = apSegment[0]->iDocid;
         fts3SegReaderNextDocid(p, apSegment[0], &pList, &nList);
@@ -129305,7 +132369,7 @@ SQLITE_PRIVATE int sqlite3Fts3SegReaderStep(
         }
 
         if( isColFilter ){
-          fts3ColumnFilter(pFilter->iCol, &pList, &nList);
+          fts3ColumnFilter(pFilter->iCol, 0, &pList, &nList);
         }
 
         if( !isIgnoreEmpty || nList>0 ){
@@ -129421,7 +132485,7 @@ static int fts3SegmentMerge(
 
   if( iLevel==FTS3_SEGCURSOR_ALL ){
     /* This call is to merge all segments in the database to a single
-    ** segment. The level of the new segment is equal to the the numerically 
+    ** segment. The level of the new segment is equal to the numerically
     ** greatest segment level currently present in the database for this
     ** index. The idx of the new segment is always 0.  */
     if( csr.nSegment==1 ){
@@ -129742,11 +132806,13 @@ static int fts3DoRebuild(Fts3Table *p){
       int iCol;
       int iLangid = langidFromSelect(p, pStmt);
       rc = fts3PendingTermsDocid(p, iLangid, sqlite3_column_int64(pStmt, 0));
-      aSz[p->nColumn] = 0;
+      memset(aSz, 0, sizeof(aSz[0]) * (p->nColumn+1));
       for(iCol=0; rc==SQLITE_OK && iCol<p->nColumn; iCol++){
-        const char *z = (const char *) sqlite3_column_text(pStmt, iCol+1);
-        rc = fts3PendingTermsAdd(p, iLangid, z, iCol, &aSz[iCol]);
-        aSz[p->nColumn] += sqlite3_column_bytes(pStmt, iCol+1);
+        if( p->abNotindexed[iCol]==0 ){
+          const char *z = (const char *) sqlite3_column_text(pStmt, iCol+1);
+          rc = fts3PendingTermsAdd(p, iLangid, z, iCol, &aSz[iCol]);
+          aSz[p->nColumn] += sqlite3_column_bytes(pStmt, iCol+1);
+        }
       }
       if( p->bHasDocsize ){
         fts3InsertDocsize(&rc, p, aSz);
@@ -130051,7 +133117,7 @@ static int fts3IncrmergePush(
         pNode->key.n = nTerm;
       }
     }else{
-      /* Otherwise, flush the the current node of layer iLayer to disk.
+      /* Otherwise, flush the current node of layer iLayer to disk.
       ** Then allocate a new, empty sibling node. The key will be written
       ** into the parent of this node. */
       rc = fts3WriteSegment(p, pNode->iBlock, pNode->block.a, pNode->block.n);
@@ -131386,9 +134452,9 @@ static int fts3IntegrityCheck(Fts3Table *p, int *pbOk){
         rc = sqlite3Fts3OpenTokenizer(p->pTokenizer, iLang, zText, nText, &pT);
         while( rc==SQLITE_OK ){
           char const *zToken;       /* Buffer containing token */
-          int nToken;               /* Number of bytes in token */
-          int iDum1, iDum2;         /* Dummy variables */
-          int iPos;                 /* Position of token in zText */
+          int nToken = 0;           /* Number of bytes in token */
+          int iDum1 = 0, iDum2 = 0; /* Dummy variables */
+          int iPos = 0;             /* Position of token in zText */
 
           rc = pModule->xNext(pT, &zToken, &nToken, &iDum1, &iDum2, &iPos);
           if( rc==SQLITE_OK ){
@@ -131498,6 +134564,7 @@ static int fts3SpecialInsert(Fts3Table *p, sqlite3_value *pVal){
   return rc;
 }
 
+#ifndef SQLITE_DISABLE_FTS4_DEFERRED
 /*
 ** Delete all cached deferred doclists. Deferred doclists are cached
 ** (allocated) by the sqlite3Fts3CacheDeferredDoclists() function.
@@ -131548,32 +134615,34 @@ SQLITE_PRIVATE int sqlite3Fts3CacheDeferredDoclists(Fts3Cursor *pCsr){
     iDocid = sqlite3_column_int64(pCsr->pStmt, 0);
   
     for(i=0; i<p->nColumn && rc==SQLITE_OK; i++){
-      const char *zText = (const char *)sqlite3_column_text(pCsr->pStmt, i+1);
-      sqlite3_tokenizer_cursor *pTC = 0;
-  
-      rc = sqlite3Fts3OpenTokenizer(pT, pCsr->iLangid, zText, -1, &pTC);
-      while( rc==SQLITE_OK ){
-        char const *zToken;       /* Buffer containing token */
-        int nToken;               /* Number of bytes in token */
-        int iDum1, iDum2;         /* Dummy variables */
-        int iPos;                 /* Position of token in zText */
-  
-        rc = pModule->xNext(pTC, &zToken, &nToken, &iDum1, &iDum2, &iPos);
-        for(pDef=pCsr->pDeferred; pDef && rc==SQLITE_OK; pDef=pDef->pNext){
-          Fts3PhraseToken *pPT = pDef->pToken;
-          if( (pDef->iCol>=p->nColumn || pDef->iCol==i)
-           && (pPT->bFirst==0 || iPos==0)
-           && (pPT->n==nToken || (pPT->isPrefix && pPT->n<nToken))
-           && (0==memcmp(zToken, pPT->z, pPT->n))
-          ){
-            fts3PendingListAppend(&pDef->pList, iDocid, i, iPos, &rc);
+      if( p->abNotindexed[i]==0 ){
+        const char *zText = (const char *)sqlite3_column_text(pCsr->pStmt, i+1);
+        sqlite3_tokenizer_cursor *pTC = 0;
+
+        rc = sqlite3Fts3OpenTokenizer(pT, pCsr->iLangid, zText, -1, &pTC);
+        while( rc==SQLITE_OK ){
+          char const *zToken;       /* Buffer containing token */
+          int nToken = 0;           /* Number of bytes in token */
+          int iDum1 = 0, iDum2 = 0; /* Dummy variables */
+          int iPos = 0;             /* Position of token in zText */
+
+          rc = pModule->xNext(pTC, &zToken, &nToken, &iDum1, &iDum2, &iPos);
+          for(pDef=pCsr->pDeferred; pDef && rc==SQLITE_OK; pDef=pDef->pNext){
+            Fts3PhraseToken *pPT = pDef->pToken;
+            if( (pDef->iCol>=p->nColumn || pDef->iCol==i)
+                && (pPT->bFirst==0 || iPos==0)
+                && (pPT->n==nToken || (pPT->isPrefix && pPT->n<nToken))
+                && (0==memcmp(zToken, pPT->z, pPT->n))
+              ){
+              fts3PendingListAppend(&pDef->pList, iDocid, i, iPos, &rc);
+            }
           }
         }
+        if( pTC ) pModule->xClose(pTC);
+        if( rc==SQLITE_DONE ) rc = SQLITE_OK;
       }
-      if( pTC ) pModule->xClose(pTC);
-      if( rc==SQLITE_DONE ) rc = SQLITE_OK;
     }
-  
+
     for(pDef=pCsr->pDeferred; pDef && rc==SQLITE_OK; pDef=pDef->pNext){
       if( pDef->pList ){
         rc = fts3PendingListAppendVarint(&pDef->pList, 0);
@@ -131635,6 +134704,7 @@ SQLITE_PRIVATE int sqlite3Fts3DeferToken(
 
   return SQLITE_OK;
 }
+#endif
 
 /*
 ** SQLite value pRowid contains the rowid of a row that may or may not be
@@ -131644,28 +134714,32 @@ SQLITE_PRIVATE int sqlite3Fts3DeferToken(
 static int fts3DeleteByRowid(
   Fts3Table *p, 
   sqlite3_value *pRowid, 
-  int *pnDoc,
+  int *pnChng,                    /* IN/OUT: Decrement if row is deleted */
   u32 *aSzDel
 ){
-  int isEmpty = 0;
-  int rc = fts3IsEmpty(p, pRowid, &isEmpty);
-  if( rc==SQLITE_OK ){
-    if( isEmpty ){
-      /* Deleting this row means the whole table is empty. In this case
-      ** delete the contents of all three tables and throw away any
-      ** data in the pendingTerms hash table.  */
-      rc = fts3DeleteAll(p, 1);
-      *pnDoc = *pnDoc - 1;
-    }else{
-      fts3DeleteTerms(&rc, p, pRowid, aSzDel);
-      if( p->zContentTbl==0 ){
-        fts3SqlExec(&rc, p, SQL_DELETE_CONTENT, &pRowid);
-        if( sqlite3_changes(p->db) ) *pnDoc = *pnDoc - 1;
+  int rc = SQLITE_OK;             /* Return code */
+  int bFound = 0;                 /* True if *pRowid really is in the table */
+
+  fts3DeleteTerms(&rc, p, pRowid, aSzDel, &bFound);
+  if( bFound && rc==SQLITE_OK ){
+    int isEmpty = 0;              /* Deleting *pRowid leaves the table empty */
+    rc = fts3IsEmpty(p, pRowid, &isEmpty);
+    if( rc==SQLITE_OK ){
+      if( isEmpty ){
+        /* Deleting this row means the whole table is empty. In this case
+        ** delete the contents of all three tables and throw away any
+        ** data in the pendingTerms hash table.  */
+        rc = fts3DeleteAll(p, 1);
+        *pnChng = 0;
+        memset(aSzDel, 0, sizeof(u32) * (p->nColumn+1) * 2);
       }else{
-        *pnDoc = *pnDoc - 1;
-      }
-      if( p->bHasDocsize ){
-        fts3SqlExec(&rc, p, SQL_DELETE_DOCSIZE, &pRowid);
+        *pnChng = *pnChng - 1;
+        if( p->zContentTbl==0 ){
+          fts3SqlExec(&rc, p, SQL_DELETE_CONTENT, &pRowid);
+        }
+        if( p->bHasDocsize ){
+          fts3SqlExec(&rc, p, SQL_DELETE_DOCSIZE, &pRowid);
+        }
       }
     }
   }
@@ -131696,7 +134770,7 @@ SQLITE_PRIVATE int sqlite3Fts3UpdateMethod(
   int rc = SQLITE_OK;             /* Return Code */
   int isRemove = 0;               /* True for an UPDATE or DELETE */
   u32 *aSzIns = 0;                /* Sizes of inserted documents */
-  u32 *aSzDel;                    /* Sizes of deleted documents */
+  u32 *aSzDel = 0;                /* Sizes of deleted documents */
   int nChng = 0;                  /* Net change in number of documents */
   int bInsertDone = 0;
 
@@ -131724,13 +134798,16 @@ SQLITE_PRIVATE int sqlite3Fts3UpdateMethod(
   }
 
   /* Allocate space to hold the change in document sizes */
-  aSzIns = sqlite3_malloc( sizeof(aSzIns[0])*(p->nColumn+1)*2 );
-  if( aSzIns==0 ){
+  aSzDel = sqlite3_malloc( sizeof(aSzDel[0])*(p->nColumn+1)*2 );
+  if( aSzDel==0 ){
     rc = SQLITE_NOMEM;
     goto update_out;
   }
-  aSzDel = &aSzIns[p->nColumn+1];
-  memset(aSzIns, 0, sizeof(aSzIns[0])*(p->nColumn+1)*2);
+  aSzIns = &aSzDel[p->nColumn+1];
+  memset(aSzDel, 0, sizeof(aSzDel[0])*(p->nColumn+1)*2);
+
+  rc = fts3Writelock(p);
+  if( rc!=SQLITE_OK ) goto update_out;
 
   /* If this is an INSERT operation, or an UPDATE that modifies the rowid
   ** value, then this operation requires constraint handling.
@@ -131815,7 +134892,7 @@ SQLITE_PRIVATE int sqlite3Fts3UpdateMethod(
   }
 
  update_out:
-  sqlite3_free(aSzIns);
+  sqlite3_free(aSzDel);
   sqlite3Fts3SegmentsClose(p);
   return rc;
 }
@@ -132236,9 +135313,9 @@ static int fts3SnippetFindPositions(Fts3Expr *pExpr, int iPhrase, void *ctx){
 ** is the snippet with the highest score, where scores are calculated
 ** by adding:
 **
-**   (a) +1 point for each occurence of a matchable phrase in the snippet.
+**   (a) +1 point for each occurrence of a matchable phrase in the snippet.
 **
-**   (b) +1000 points for the first occurence of each matchable phrase in 
+**   (b) +1000 points for the first occurrence of each matchable phrase in 
 **       the snippet for which the corresponding mCovered bit is not set.
 **
 ** The selected snippet parameters are stored in structure *pFragment before
@@ -132351,6 +135428,7 @@ static int fts3StringAppend(
     pStr->z = zNew;
     pStr->nAlloc = nAlloc;
   }
+  assert( pStr->z!=0 && (pStr->nAlloc >= pStr->n+nAppend+1) );
 
   /* Append the data to the string buffer. */
   memcpy(&pStr->z[pStr->n], zAppend, nAppend);
@@ -132423,7 +135501,7 @@ static int fts3SnippetShift(
         return rc;
       }
       while( rc==SQLITE_OK && iCurrent<(nSnippet+nDesired) ){
-        const char *ZDUMMY; int DUMMY1, DUMMY2, DUMMY3;
+        const char *ZDUMMY; int DUMMY1 = 0, DUMMY2 = 0, DUMMY3 = 0;
         rc = pMod->xNext(pC, &ZDUMMY, &DUMMY1, &DUMMY2, &DUMMY3, &iCurrent);
       }
       pMod->xClose(pC);
@@ -132467,8 +135545,6 @@ static int fts3SnippetText(
   int iCol = pFragment->iCol+1;   /* Query column to extract text from */
   sqlite3_tokenizer_module *pMod; /* Tokenizer module methods object */
   sqlite3_tokenizer_cursor *pC;   /* Tokenizer cursor open on zDoc/nDoc */
-  const char *ZDUMMY;             /* Dummy argument used with tokenizer */
-  int DUMMY1;                     /* Dummy argument used with tokenizer */
   
   zDoc = (const char *)sqlite3_column_text(pCsr->pStmt, iCol);
   if( zDoc==0 ){
@@ -132487,10 +135563,23 @@ static int fts3SnippetText(
   }
 
   while( rc==SQLITE_OK ){
-    int iBegin;                   /* Offset in zDoc of start of token */
-    int iFin;                     /* Offset in zDoc of end of token */
-    int isHighlight;              /* True for highlighted terms */
+    const char *ZDUMMY;           /* Dummy argument used with tokenizer */
+    int DUMMY1 = -1;              /* Dummy argument used with tokenizer */
+    int iBegin = 0;               /* Offset in zDoc of start of token */
+    int iFin = 0;                 /* Offset in zDoc of end of token */
+    int isHighlight = 0;          /* True for highlighted terms */
 
+    /* Variable DUMMY1 is initialized to a negative value above. Elsewhere
+    ** in the FTS code the variable that the third argument to xNext points to
+    ** is initialized to zero before the first (*but not necessarily
+    ** subsequent*) call to xNext(). This is done for a particular application
+    ** that needs to know whether or not the tokenizer is being used for
+    ** snippet generation or for some other purpose.
+    **
+    ** Extreme care is required when writing code to depend on this
+    ** initialization. It is not a documented part of the tokenizer interface.
+    ** If a tokenizer is used directly by any code outside of FTS, this
+    ** convention might not be respected.  */
     rc = pMod->xNext(pC, &ZDUMMY, &DUMMY1, &iBegin, &iFin, &iCurrent);
     if( rc!=SQLITE_OK ){
       if( rc==SQLITE_DONE ){
@@ -133180,8 +136269,6 @@ SQLITE_PRIVATE void sqlite3Fts3Offsets(
 ){
   Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
   sqlite3_tokenizer_module const *pMod = pTab->pTokenizer->pModule;
-  const char *ZDUMMY;             /* Dummy argument used with xNext() */
-  int NDUMMY;                     /* Dummy argument used with xNext() */
   int rc;                         /* Return Code */
   int nToken;                     /* Number of tokens in query */
   int iCol;                       /* Column currently being processed */
@@ -133214,9 +136301,11 @@ SQLITE_PRIVATE void sqlite3Fts3Offsets(
   */
   for(iCol=0; iCol<pTab->nColumn; iCol++){
     sqlite3_tokenizer_cursor *pC; /* Tokenizer cursor */
-    int iStart;
-    int iEnd;
-    int iCurrent;
+    const char *ZDUMMY;           /* Dummy argument used with xNext() */
+    int NDUMMY = 0;               /* Dummy argument used with xNext() */
+    int iStart = 0;
+    int iEnd = 0;
+    int iCurrent = 0;
     const char *zDoc;
     int nDoc;
 
@@ -133482,7 +136571,7 @@ static int unicodeDestroy(sqlite3_tokenizer *pTokenizer){
 **
 ** If a standalone diacritic mark (one that sqlite3FtsUnicodeIsdiacritic()
 ** identifies as a diacritic) occurs in the zIn/nIn string it is ignored.
-** It is not possible to change the behaviour of the tokenizer with respect
+** It is not possible to change the behavior of the tokenizer with respect
 ** to these codepoints.
 */
 static int unicodeAddExceptions(
@@ -133854,28 +136943,27 @@ SQLITE_PRIVATE int sqlite3FtsUnicodeIsalnum(int c){
     0x02A97004, 0x02A9DC03, 0x02A9EC01, 0x02AAC001, 0x02AAC803,
     0x02AADC02, 0x02AAF802, 0x02AB0401, 0x02AB7802, 0x02ABAC07,
     0x02ABD402, 0x02AF8C0B, 0x03600001, 0x036DFC02, 0x036FFC02,
-    0x037FFC02, 0x03E3FC01, 0x03EC7801, 0x03ECA401, 0x03EEC810,
-    0x03F4F802, 0x03F7F002, 0x03F8001A, 0x03F88007, 0x03F8C023,
-    0x03F95013, 0x03F9A004, 0x03FBFC01, 0x03FC040F, 0x03FC6807,
-    0x03FCEC06, 0x03FD6C0B, 0x03FF8007, 0x03FFA007, 0x03FFE405,
-    0x04040003, 0x0404DC09, 0x0405E411, 0x0406400C, 0x0407402E,
-    0x040E7C01, 0x040F4001, 0x04215C01, 0x04247C01, 0x0424FC01,
-    0x04280403, 0x04281402, 0x04283004, 0x0428E003, 0x0428FC01,
-    0x04294009, 0x0429FC01, 0x042CE407, 0x04400003, 0x0440E016,
-    0x04420003, 0x0442C012, 0x04440003, 0x04449C0E, 0x04450004,
-    0x04460003, 0x0446CC0E, 0x04471404, 0x045AAC0D, 0x0491C004,
-    0x05BD442E, 0x05BE3C04, 0x074000F6, 0x07440027, 0x0744A4B5,
-    0x07480046, 0x074C0057, 0x075B0401, 0x075B6C01, 0x075BEC01,
-    0x075C5401, 0x075CD401, 0x075D3C01, 0x075DBC01, 0x075E2401,
-    0x075EA401, 0x075F0C01, 0x07BBC002, 0x07C0002C, 0x07C0C064,
-    0x07C2800F, 0x07C2C40E, 0x07C3040F, 0x07C3440F, 0x07C4401F,
-    0x07C4C03C, 0x07C5C02B, 0x07C7981D, 0x07C8402B, 0x07C90009,
-    0x07C94002, 0x07CC0021, 0x07CCC006, 0x07CCDC46, 0x07CE0014,
-    0x07CE8025, 0x07CF1805, 0x07CF8011, 0x07D0003F, 0x07D10001,
-    0x07D108B6, 0x07D3E404, 0x07D4003E, 0x07D50004, 0x07D54018,
-    0x07D7EC46, 0x07D9140B, 0x07DA0046, 0x07DC0074, 0x38000401,
-    0x38008060, 0x380400F0, 0x3C000001, 0x3FFFF401, 0x40000001,
-    0x43FFF401,
+    0x037FFC01, 0x03EC7801, 0x03ECA401, 0x03EEC810, 0x03F4F802,
+    0x03F7F002, 0x03F8001A, 0x03F88007, 0x03F8C023, 0x03F95013,
+    0x03F9A004, 0x03FBFC01, 0x03FC040F, 0x03FC6807, 0x03FCEC06,
+    0x03FD6C0B, 0x03FF8007, 0x03FFA007, 0x03FFE405, 0x04040003,
+    0x0404DC09, 0x0405E411, 0x0406400C, 0x0407402E, 0x040E7C01,
+    0x040F4001, 0x04215C01, 0x04247C01, 0x0424FC01, 0x04280403,
+    0x04281402, 0x04283004, 0x0428E003, 0x0428FC01, 0x04294009,
+    0x0429FC01, 0x042CE407, 0x04400003, 0x0440E016, 0x04420003,
+    0x0442C012, 0x04440003, 0x04449C0E, 0x04450004, 0x04460003,
+    0x0446CC0E, 0x04471404, 0x045AAC0D, 0x0491C004, 0x05BD442E,
+    0x05BE3C04, 0x074000F6, 0x07440027, 0x0744A4B5, 0x07480046,
+    0x074C0057, 0x075B0401, 0x075B6C01, 0x075BEC01, 0x075C5401,
+    0x075CD401, 0x075D3C01, 0x075DBC01, 0x075E2401, 0x075EA401,
+    0x075F0C01, 0x07BBC002, 0x07C0002C, 0x07C0C064, 0x07C2800F,
+    0x07C2C40E, 0x07C3040F, 0x07C3440F, 0x07C4401F, 0x07C4C03C,
+    0x07C5C02B, 0x07C7981D, 0x07C8402B, 0x07C90009, 0x07C94002,
+    0x07CC0021, 0x07CCC006, 0x07CCDC46, 0x07CE0014, 0x07CE8025,
+    0x07CF1805, 0x07CF8011, 0x07D0003F, 0x07D10001, 0x07D108B6,
+    0x07D3E404, 0x07D4003E, 0x07D50004, 0x07D54018, 0x07D7EC46,
+    0x07D9140B, 0x07DA0046, 0x07DC0074, 0x38000401, 0x38008060,
+    0x380400F0,
   };
   static const unsigned int aAscii[4] = {
     0xFFFFFFFF, 0xFC00FFFF, 0xF8000001, 0xF8000001,
@@ -133899,7 +136987,7 @@ SQLITE_PRIVATE int sqlite3FtsUnicodeIsalnum(int c){
     }
     assert( aEntry[0]<key );
     assert( key>=aEntry[iRes] );
-    return (c >= ((aEntry[iRes]>>10) + (aEntry[iRes]&0x3FF)));
+    return (((unsigned int)c) >= ((aEntry[iRes]>>10) + (aEntry[iRes]&0x3FF)));
   }
   return 1;
 }
@@ -136780,12 +139868,12 @@ static int newRowid(Rtree *pRtree, i64 *piRowid){
 */
 static int rtreeDeleteRowid(Rtree *pRtree, sqlite3_int64 iDelete){
   int rc;                         /* Return code */
-  RtreeNode *pLeaf;               /* Leaf node containing record iDelete */
+  RtreeNode *pLeaf = 0;           /* Leaf node containing record iDelete */
   int iCell;                      /* Index of iDelete cell in pLeaf */
   RtreeNode *pRoot;               /* Root node of rtree structure */
 
 
-  /* Obtain a reference to the root node to initialise Rtree.iDepth */
+  /* Obtain a reference to the root node to initialize Rtree.iDepth */
   rc = nodeAcquire(pRtree, 1, 0, &pRoot);
 
   /* Obtain a reference to the leaf node that contains the entry 
@@ -136983,7 +140071,7 @@ static int rtreeUpdate(
   */
   if( rc==SQLITE_OK && nData>1 ){
     /* Insert the new record into the r-tree */
-    RtreeNode *pLeaf;
+    RtreeNode *pLeaf = 0;
 
     /* Figure out the rowid of the new row. */
     if( bHaveRowid==0 ){
@@ -137169,7 +140257,8 @@ static int getIntFromStmt(sqlite3 *db, const char *zSql, int *piVal){
 static int getNodeSize(
   sqlite3 *db,                    /* Database handle */
   Rtree *pRtree,                  /* Rtree handle */
-  int isCreate                    /* True for xCreate, false for xConnect */
+  int isCreate,                   /* True for xCreate, false for xConnect */
+  char **pzErr                    /* OUT: Error message, if any */
 ){
   int rc;
   char *zSql;
@@ -137182,6 +140271,8 @@ static int getNodeSize(
       if( (4+pRtree->nBytesPerCell*RTREE_MAXCELLS)<pRtree->iNodeSize ){
         pRtree->iNodeSize = 4+pRtree->nBytesPerCell*RTREE_MAXCELLS;
       }
+    }else{
+      *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(db));
     }
   }else{
     zSql = sqlite3_mprintf(
@@ -137189,6 +140280,9 @@ static int getNodeSize(
         pRtree->zDb, pRtree->zName
     );
     rc = getIntFromStmt(db, zSql, &pRtree->iNodeSize);
+    if( rc!=SQLITE_OK ){
+      *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(db));
+    }
   }
 
   sqlite3_free(zSql);
@@ -137252,7 +140346,7 @@ static int rtreeInit(
   memcpy(pRtree->zName, argv[2], nName);
 
   /* Figure out the node size to use. */
-  rc = getNodeSize(db, pRtree, isCreate);
+  rc = getNodeSize(db, pRtree, isCreate, pzErr);
 
   /* Create/Connect to the underlying relational database schema. If
   ** that is successful, call sqlite3_declare_vtab() to configure
@@ -137464,7 +140558,10 @@ SQLITE_API int sqlite3_rtree_geometry_callback(
 }
 
 #if !SQLITE_CORE
-SQLITE_API int sqlite3_extension_init(
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+SQLITE_API int sqlite3_rtree_init(
   sqlite3 *db,
   char **pzErrMsg,
   const sqlite3_api_routines *pApi
@@ -137502,7 +140599,7 @@ SQLITE_API int sqlite3_extension_init(
 **   * Implementations of the SQL scalar upper() and lower() functions
 **     for case mapping.
 **
-**   * Integration of ICU and SQLite collation seqences.
+**   * Integration of ICU and SQLite collation sequences.
 **
 **   * An implementation of the LIKE operator that uses ICU to 
 **     provide case-independent matching.
@@ -137966,7 +141063,10 @@ SQLITE_PRIVATE int sqlite3IcuInit(sqlite3 *db){
 }
 
 #if !SQLITE_CORE
-SQLITE_API int sqlite3_extension_init(
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+SQLITE_API int sqlite3_icu_init(
   sqlite3 *db, 
   char **pzErrMsg,
   const sqlite3_api_routines *pApi
@@ -138099,7 +141199,7 @@ static int icuOpen(
   nChar = nInput+1;
   pCsr = (IcuCursor *)sqlite3_malloc(
       sizeof(IcuCursor) +                /* IcuCursor */
-      nChar * sizeof(UChar) +            /* IcuCursor.aChar[] */
+      ((nChar+3)&~3) * sizeof(UChar) +   /* IcuCursor.aChar[] */
       (nChar+1) * sizeof(int)            /* IcuCursor.aOffset[] */
   );
   if( !pCsr ){
@@ -138107,7 +141207,7 @@ static int icuOpen(
   }
   memset(pCsr, 0, sizeof(IcuCursor));
   pCsr->aChar = (UChar *)&pCsr[1];
-  pCsr->aOffset = (int *)&pCsr->aChar[nChar];
+  pCsr->aOffset = (int *)&pCsr->aChar[(nChar+3)&~3];
 
   pCsr->aOffset[iOut] = iInput;
   U8_NEXT(zInput, iInput, nInput, c); 
@@ -138179,7 +141279,7 @@ static int icuNext(
 
     while( iStart<iEnd ){
       int iWhite = iStart;
-      U8_NEXT(pCsr->aChar, iWhite, pCsr->nChar, c);
+      U16_NEXT(pCsr->aChar, iWhite, pCsr->nChar, c);
       if( u_isspace(c) ){
         iStart = iWhite;
       }else{
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2e3fbf522..dec590cc7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -234,15 +234,24 @@ if(ENABLE_LIBSVN)
     endif(LIBSVN_FOUND)
 endif(ENABLE_LIBSVN)
 
+##############################################################################
+## Sqlite3 setup
+
 if (SYSTEM_SQLITE)
     find_package(SQLite3 REQUIRED)
-    set(CMAKE_REQUIRED_INCLUDES ${SQLITE3_INCLUDED_DIR})
+    
     message(STATUS "Using system SQLite3 library")
+else()
+    set(SQLITE3_INCLUDED_DIR "${CMAKE_SOURCE_DIR}/3rdparty/sqlite3")
+    # this target is defined in src/Navaids/CMakeLists.txt
+    list(APPEND SQLITE3_LIBRARY fgsqlite3)
 endif (SYSTEM_SQLITE)
 
 # Sqlite always depends on the threading lib
 list(APPEND SQLITE3_LIBRARY ${CMAKE_THREAD_LIBS_INIT})
 
+##############################################################################
+
 find_package(PLIB REQUIRED puaux pu js fnt)
 
 if (EMBEDDED_SIMGEAR)
@@ -346,7 +355,8 @@ include_directories(${OPENSCENEGRAPH_INCLUDE_DIRS}
     ${OPENGL_INCLUDE_DIR}
     ${OPENAL_INCLUDE_DIR}
     ${SIMGEAR_INCLUDE_DIR}
-    ${PLIB_INCLUDE_DIR} )
+    ${PLIB_INCLUDE_DIR}
+    ${SQLITE3_INCLUDED_DIR} )
 
 include_directories(${PROJECT_SOURCE_DIR})
 include_directories(${PROJECT_SOURCE_DIR}/src)
@@ -386,6 +396,7 @@ if (EMBEDDED_SIMGEAR)
     include_directories(${PROJECT_BINARY_DIR}/simgear)
 endif(EMBEDDED_SIMGEAR)
 
+add_subdirectory(3rdparty)
 add_subdirectory(utils)
 add_subdirectory(src)
 add_subdirectory(man)
diff --git a/src/Main/CMakeLists.txt b/src/Main/CMakeLists.txt
index bb996cad3..338a9f6d4 100644
--- a/src/Main/CMakeLists.txt
+++ b/src/Main/CMakeLists.txt
@@ -69,11 +69,6 @@ source_group("Main\\Headers" FILES ${HEADERS})
 source_group("Main\\Sources" FILES ${SOURCES})
 add_executable(fgfs ${SOURCES} ${FG_SOURCES} ${FG_HEADERS} ${HEADERS})
 
-# disable sqlite3 dynamic lib support
-# this should really be a SOURCE property, but the way we handle
-# Fcomponent sources is making that tricky
-add_definitions(-DSQLITE_OMIT_LOAD_EXTENSION)
-
 get_property(FG_LIBS GLOBAL PROPERTY FG_LIBS)
 #message(STATUS "fg libs ${FG_LIBS}")
 #message(STATUS "OSG libs ${OPENSCENEGRAPH_LIBRARIES}")
diff --git a/src/Navaids/CMakeLists.txt b/src/Navaids/CMakeLists.txt
index 485a7ac62..1d33ea12f 100644
--- a/src/Navaids/CMakeLists.txt
+++ b/src/Navaids/CMakeLists.txt
@@ -40,9 +40,4 @@ set(HEADERS
     PolyLine.hxx
     )
 
-if (NOT SYSTEM_SQLITE)
-    list(APPEND SOURCES sqlite3.c)
-    list(APPEND HEADERS sqlite3.h)
-endif()
-
 flightgear_component(Navaids "${SOURCES}" "${HEADERS}")
diff --git a/src/Navaids/NavDataCache.cxx b/src/Navaids/NavDataCache.cxx
index 2d44a8805..0ecb29258 100644
--- a/src/Navaids/NavDataCache.cxx
+++ b/src/Navaids/NavDataCache.cxx
@@ -23,11 +23,6 @@
 # include "config.h"
 #endif
 
-// to ensure compatability between sqlite3_int64 and PositionedID,
-// force the type used by sqlite to match PositionedID explicitly
-#define SQLITE_INT64_TYPE int64_t
-#define SQLITE_UINT64_TYPE uint64_t
-
 #include "NavDataCache.hxx"
 
 // std
@@ -37,7 +32,16 @@
 // boost
 #include <boost/foreach.hpp>
 
-#include "sqlite3.h"
+// to ensure compatability between sqlite3_int64 and PositionedID,
+// force the type used by sqlite to match PositionedID explicitly
+#define SQLITE_INT64_TYPE int64_t
+#define SQLITE_UINT64_TYPE uint64_t
+
+#ifdef SYSTEM_SQLITE
+  #include "sqlite3.h"
+#else
+  #include "fg_sqlite3.h"
+#endif
 
 // SimGear
 #include <simgear/sg_inlines.h>