Update SQLITE version to 3.42.0 (#15870)

* Update sqlite version to 3.42.0
Suppress a compilation warning

* Enable SQLITE_ENABLE_DBPAGE_VTAB to allow recover code to be embedded in a followup PR
Suppress unused parameter warning

1 files changed, 4671 insertions, 2294 deletions

diff --git a/database/sqlite/sqlite3.c b/database/sqlite/sqlite3.c
index 005aab85a9..da8c38d091 100644
--- a/database/sqlite/sqlite3.c
+++ b/database/sqlite/sqlite3.c
@@ -1,6 +1,6 @@
 /******************************************************************************
 ** This file is an amalgamation of many separate C source files from SQLite
-** version 3.41.2.  By combining all the individual C code files into this
+** version 3.42.0.  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
@@ -17,6 +17,9 @@
 ** language. The code for the "sqlite3" command-line shell is also in a
 ** separate file. This file contains only code for the core SQLite library.
 */
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
+#pragma GCC diagnostic ignored "-Wunused-parameter"
 #define SQLITE_CORE 1
 #define SQLITE_AMALGAMATION 1
 #ifndef SQLITE_PRIVATE
@@ -26,6 +29,7 @@
 #define SQLITE_ENABLE_UPDATE_DELETE_LIMIT 1
 #define SQLITE_OMIT_LOAD_EXTENSION 1
 #define SQLITE_ENABLE_DBSTAT_VTAB 1
+#define SQLITE_ENABLE_DBPAGE_VTAB 1
 /************** Begin file sqliteInt.h ***************************************/
 /*
 ** 2001 September 15
@@ -127,6 +131,10 @@
 #define SQLITE_4_BYTE_ALIGNED_MALLOC
 #endif /* defined(_MSC_VER) && !defined(_WIN64) */
 
+#if !defined(HAVE_LOG2) && defined(_MSC_VER) && _MSC_VER<1800
+#define HAVE_LOG2 0
+#endif /* !defined(HAVE_LOG2) && defined(_MSC_VER) && _MSC_VER<1800 */
+
 #endif /* SQLITE_MSVC_H */
 
 /************** End of msvc.h ************************************************/
@@ -456,9 +464,9 @@ extern "C" {
 ** [sqlite3_libversion_number()], [sqlite3_sourceid()],
 ** [sqlite_version()] and [sqlite_source_id()].
 */
-#define SQLITE_VERSION        "3.41.2"
-#define SQLITE_VERSION_NUMBER 3041002
-#define SQLITE_SOURCE_ID      "2023-03-22 11:56:21 0d1fc92f94cb6b76bffe3ec34d69cffde2924203304e8ffc4155597af0c191da"
+#define SQLITE_VERSION        "3.42.0"
+#define SQLITE_VERSION_NUMBER 3042000
+#define SQLITE_SOURCE_ID      "2023-05-16 12:36:15 831d0fb2836b71c9bc51067c49fee4b8f18047814f2ff22d817d25195cf350b0"
 
 /*
 ** CAPI3REF: Run-Time Library Version Numbers
@@ -1965,20 +1973,23 @@ SQLITE_API int sqlite3_os_end(void);
 ** must ensure that no other SQLite interfaces are invoked by other
 ** threads while sqlite3_config() is running.</b>
 **
-** The sqlite3_config() interface
-** may only be invoked prior to library initialization using
-** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
-** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
-** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.
-** Note, however, that ^sqlite3_config() can be called as part of the
-** implementation of an application-defined [sqlite3_os_init()].
-**
 ** The first argument to sqlite3_config() is an integer
 ** [configuration option] that determines
 ** what property of SQLite is to be configured.  Subsequent arguments
 ** vary depending on the [configuration option]
 ** in the first argument.
 **
+** For most configuration options, the sqlite3_config() interface
+** may only be invoked prior to library initialization using
+** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].
+** The exceptional configuration options that may be invoked at any time
+** are called "anytime configuration options".
+** ^If sqlite3_config() is called after [sqlite3_initialize()] and before
+** [sqlite3_shutdown()] with a first argument that is not an anytime
+** configuration option, then the sqlite3_config() call will return SQLITE_MISUSE.
+** Note, however, that ^sqlite3_config() can be called as part of the
+** implementation of an application-defined [sqlite3_os_init()].
+**
 ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
 ** ^If the option is unknown or SQLite is unable to set the option
 ** then this routine returns a non-zero [error code].
@@ -2086,6 +2097,23 @@ struct sqlite3_mem_methods {
 ** These constants are the available integer configuration options that
 ** can be passed as the first argument to the [sqlite3_config()] interface.
 **
+** Most of the configuration options for sqlite3_config()
+** will only work if invoked prior to [sqlite3_initialize()] or after
+** [sqlite3_shutdown()].  The few exceptions to this rule are called
+** "anytime configuration options".
+** ^Calling [sqlite3_config()] with a first argument that is not an
+** anytime configuration option in between calls to [sqlite3_initialize()] and
+** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE.
+**
+** The set of anytime configuration options can change (by insertions
+** and/or deletions) from one release of SQLite to the next.
+** As of SQLite version 3.42.0, the complete set of anytime configuration
+** options is:
+** <ul>
+** <li> SQLITE_CONFIG_LOG
+** <li> SQLITE_CONFIG_PCACHE_HDRSZ
+** </ul>
+**
 ** New configuration options may be added in future releases of SQLite.
 ** Existing configuration options might be discontinued.  Applications
 ** should check the return code from [sqlite3_config()] to make sure that
@@ -2432,28 +2460,28 @@ struct sqlite3_mem_methods {
 ** compile-time option is not set, then the default maximum is 1073741824.
 ** </dl>
 */
-#define SQLITE_CONFIG_SINGLETHREAD  1  /* nil */
-#define SQLITE_CONFIG_MULTITHREAD   2  /* nil */
-#define SQLITE_CONFIG_SERIALIZED    3  /* nil */
-#define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
-#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
-#define SQLITE_CONFIG_SCRATCH       6  /* No longer used */
-#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
-#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
-#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
-#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
-#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
-/* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */
-#define SQLITE_CONFIG_LOOKASIDE    13  /* int int */
-#define SQLITE_CONFIG_PCACHE       14  /* no-op */
-#define SQLITE_CONFIG_GETPCACHE    15  /* no-op */
-#define SQLITE_CONFIG_LOG          16  /* xFunc, void* */
-#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_SINGLETHREAD         1  /* nil */
+#define SQLITE_CONFIG_MULTITHREAD          2  /* nil */
+#define SQLITE_CONFIG_SERIALIZED           3  /* nil */
+#define SQLITE_CONFIG_MALLOC               4  /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_GETMALLOC            5  /* sqlite3_mem_methods* */
+#define SQLITE_CONFIG_SCRATCH              6  /* No longer used */
+#define SQLITE_CONFIG_PAGECACHE            7  /* void*, int sz, int N */
+#define SQLITE_CONFIG_HEAP                 8  /* void*, int nByte, int min */
+#define SQLITE_CONFIG_MEMSTATUS            9  /* boolean */
+#define SQLITE_CONFIG_MUTEX               10  /* sqlite3_mutex_methods* */
+#define SQLITE_CONFIG_GETMUTEX            11  /* sqlite3_mutex_methods* */
+/* previously SQLITE_CONFIG_CHUNKALLOC    12 which is now unused. */
+#define SQLITE_CONFIG_LOOKASIDE           13  /* int int */
+#define SQLITE_CONFIG_PCACHE              14  /* no-op */
+#define SQLITE_CONFIG_GETPCACHE           15  /* no-op */
+#define SQLITE_CONFIG_LOG                 16  /* xFunc, void* */
+#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 */
+#define SQLITE_CONFIG_SQLLOG              21  /* xSqllog, void* */
+#define SQLITE_CONFIG_MMAP_SIZE           22  /* sqlite3_int64, sqlite3_int64 */
 #define SQLITE_CONFIG_WIN32_HEAPSIZE      23  /* int nByte */
 #define SQLITE_CONFIG_PCACHE_HDRSZ        24  /* int *psz */
 #define SQLITE_CONFIG_PMASZ               25  /* unsigned int szPma */
@@ -2688,7 +2716,7 @@ struct sqlite3_mem_methods {
 ** </dd>
 **
 ** [[SQLITE_DBCONFIG_DQS_DML]]
-** <dt>SQLITE_DBCONFIG_DQS_DML</td>
+** <dt>SQLITE_DBCONFIG_DQS_DML</dt>
 ** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates
 ** the legacy [double-quoted string literal] misfeature for DML statements
 ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The
@@ -2697,7 +2725,7 @@ struct sqlite3_mem_methods {
 ** </dd>
 **
 ** [[SQLITE_DBCONFIG_DQS_DDL]]
-** <dt>SQLITE_DBCONFIG_DQS_DDL</td>
+** <dt>SQLITE_DBCONFIG_DQS_DDL</dt>
 ** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates
 ** the legacy [double-quoted string literal] misfeature for DDL statements,
 ** such as CREATE TABLE and CREATE INDEX. The
@@ -2706,7 +2734,7 @@ struct sqlite3_mem_methods {
 ** </dd>
 **
 ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]]
-** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</td>
+** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</dt>
 ** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to
 ** assume that database schemas are untainted by malicious content.
 ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite
@@ -2726,7 +2754,7 @@ struct sqlite3_mem_methods {
 ** </dd>
 **
 ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]]
-** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</td>
+** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</dt>
 ** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates
 ** the legacy file format flag.  When activated, this flag causes all newly
 ** created database file to have a schema format version number (the 4-byte
@@ -2735,7 +2763,7 @@ struct sqlite3_mem_methods {
 ** any SQLite version back to 3.0.0 ([dateof:3.0.0]).  Without this setting,
 ** newly created databases are generally not understandable by SQLite versions
 ** prior to 3.3.0 ([dateof:3.3.0]).  As these words are written, there
-** is now scarcely any need to generated database files that are compatible
+** is now scarcely any need to generate database files that are compatible
 ** all the way back to version 3.0.0, and so this setting is of little
 ** practical use, but is provided so that SQLite can continue to claim the
 ** ability to generate new database files that are compatible with  version
@@ -2746,6 +2774,38 @@ struct sqlite3_mem_methods {
 ** not considered a bug since SQLite versions 3.3.0 and earlier do not support
 ** either generated columns or decending indexes.
 ** </dd>
+**
+** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]]
+** <dt>SQLITE_DBCONFIG_STMT_SCANSTATUS</dt>
+** <dd>The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in
+** SQLITE_ENABLE_STMT_SCANSTATUS builds. In this case, it sets or clears
+** a flag that enables collection of the sqlite3_stmt_scanstatus_v2()
+** statistics. For statistics to be collected, the flag must be set on
+** the database handle both when the SQL statement is prepared and when it
+** is stepped. The flag is set (collection of statistics is enabled)
+** by default.  This option takes two arguments: an integer and a pointer to
+** an integer..  The first argument is 1, 0, or -1 to enable, disable, or
+** leave unchanged the statement scanstatus option.  If the second argument
+** is not NULL, then the value of the statement scanstatus setting after
+** processing the first argument is written into the integer that the second
+** argument points to.
+** </dd>
+**
+** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]]
+** <dt>SQLITE_DBCONFIG_REVERSE_SCANORDER</dt>
+** <dd>The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order
+** in which tables and indexes are scanned so that the scans start at the end
+** and work toward the beginning rather than starting at the beginning and
+** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the
+** same as setting [PRAGMA reverse_unordered_selects].  This option takes
+** two arguments which are an integer and a pointer to an integer.  The first
+** argument is 1, 0, or -1 to enable, disable, or leave unchanged the
+** reverse scan order flag, respectively.  If the second argument is not NULL,
+** then 0 or 1 is written into the integer that the second argument points to
+** depending on if the reverse scan order flag is set after processing the
+** first argument.
+** </dd>
+**
 ** </dl>
 */
 #define SQLITE_DBCONFIG_MAINDBNAME            1000 /* const char* */
@@ -2766,7 +2826,9 @@ struct sqlite3_mem_methods {
 #define SQLITE_DBCONFIG_ENABLE_VIEW           1015 /* int int* */
 #define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT    1016 /* int int* */
 #define SQLITE_DBCONFIG_TRUSTED_SCHEMA        1017 /* int int* */
-#define SQLITE_DBCONFIG_MAX                   1017 /* Largest DBCONFIG */
+#define SQLITE_DBCONFIG_STMT_SCANSTATUS       1018 /* int int* */
+#define SQLITE_DBCONFIG_REVERSE_SCANORDER     1019 /* int int* */
+#define SQLITE_DBCONFIG_MAX                   1019 /* Largest DBCONFIG */
 
 /*
 ** CAPI3REF: Enable Or Disable Extended Result Codes
@@ -6511,6 +6573,13 @@ SQLITE_API void sqlite3_activate_cerod(
 ** of the default VFS is not implemented correctly, or not implemented at
 ** all, then the behavior of sqlite3_sleep() may deviate from the description
 ** in the previous paragraphs.
+**
+** If a negative argument is passed to sqlite3_sleep() the results vary by
+** VFS and operating system.  Some system treat a negative argument as an
+** instruction to sleep forever.  Others understand it to mean do not sleep
+** at all. ^In SQLite version 3.42.0 and later, a negative
+** argument passed into sqlite3_sleep() is changed to zero before it is relayed
+** down into the xSleep method of the VFS.
 */
 SQLITE_API int sqlite3_sleep(int);
 
@@ -8138,9 +8207,9 @@ SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*);
 ** is undefined if the mutex is not currently entered by the
 ** calling thread or is not currently allocated.
 **
-** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or
-** sqlite3_mutex_leave() is a NULL pointer, then all three routines
-** behave as no-ops.
+** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(),
+** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer,
+** then any of the four routines behaves as a no-op.
 **
 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].
 */
@@ -9874,18 +9943,28 @@ SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...);
 ** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt>
 ** <dd>Calls of the form
 ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the
-** the [xConnect] or [xCreate] methods of a [virtual table] implmentation
+** the [xConnect] or [xCreate] methods of a [virtual table] implementation
 ** identify that virtual table as being safe to use from within triggers
 ** and views.  Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the
 ** virtual table can do no serious harm even if it is controlled by a
 ** malicious hacker.  Developers should avoid setting the SQLITE_VTAB_INNOCUOUS
 ** flag unless absolutely necessary.
 ** </dd>
+**
+** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]<dt>SQLITE_VTAB_USES_ALL_SCHEMAS</dt>
+** <dd>Calls of the form
+** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the
+** the [xConnect] or [xCreate] methods of a [virtual table] implementation
+** instruct the query planner to begin at least a read transaction on
+** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the
+** virtual table is used.
+** </dd>
 ** </dl>
 */
 #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1
 #define SQLITE_VTAB_INNOCUOUS          2
 #define SQLITE_VTAB_DIRECTONLY         3
+#define SQLITE_VTAB_USES_ALL_SCHEMAS   4
 
 /*
 ** CAPI3REF: Determine The Virtual Table Conflict Policy
@@ -11060,16 +11139,20 @@ SQLITE_API int sqlite3session_create(
 SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
 
 /*
-** CAPIREF: Conigure a Session Object
+** CAPI3REF: Configure a Session Object
 ** METHOD: sqlite3_session
 **
 ** This method is used to configure a session object after it has been
-** created. At present the only valid value for the second parameter is
-** [SQLITE_SESSION_OBJCONFIG_SIZE].
+** created. At present the only valid values for the second parameter are
+** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID].
 **
-** Arguments for sqlite3session_object_config()
+*/
+SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg);
+
+/*
+** CAPI3REF: Options for sqlite3session_object_config
 **
-** The following values may passed as the the 4th parameter to
+** The following values may passed as the the 2nd parameter to
 ** sqlite3session_object_config().
 **
 ** <dt>SQLITE_SESSION_OBJCONFIG_SIZE <dd>
@@ -11085,12 +11168,21 @@ SQLITE_API void sqlite3session_delete(sqlite3_session *pSession);
 **
 **   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
 **   the first table has been attached to the session object.
+**
+** <dt>SQLITE_SESSION_OBJCONFIG_ROWID <dd>
+**   This option is used to set, clear or query the flag that enables
+**   collection of data for tables with no explicit PRIMARY KEY.
+**
+**   Normally, tables with no explicit PRIMARY KEY are simply ignored
+**   by the sessions module. However, if this flag is set, it behaves
+**   as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted
+**   as their leftmost columns.
+**
+**   It is an error (SQLITE_MISUSE) to attempt to modify this setting after
+**   the first table has been attached to the session object.
 */
-SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg);
-
-/*
-*/
-#define SQLITE_SESSION_OBJCONFIG_SIZE 1
+#define SQLITE_SESSION_OBJCONFIG_SIZE  1
+#define SQLITE_SESSION_OBJCONFIG_ROWID 2
 
 /*
 ** CAPI3REF: Enable Or Disable A Session Object
@@ -12223,9 +12315,23 @@ SQLITE_API int sqlite3changeset_apply_v2(
 **   Invert the changeset before applying it. This is equivalent to inverting
 **   a changeset using sqlite3changeset_invert() before applying it. It is
 **   an error to specify this flag with a patchset.
+**
+** <dt>SQLITE_CHANGESETAPPLY_IGNORENOOP <dd>
+**   Do not invoke the conflict handler callback for any changes that
+**   would not actually modify the database even if they were applied.
+**   Specifically, this means that the conflict handler is not invoked
+**   for:
+**    <ul>
+**    <li>a delete change if the row being deleted cannot be found,
+**    <li>an update change if the modified fields are already set to
+**        their new values in the conflicting row, or
+**    <li>an insert change if all fields of the conflicting row match
+**        the row being inserted.
+**    </ul>
 */
 #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT   0x0001
 #define SQLITE_CHANGESETAPPLY_INVERT        0x0002
+#define SQLITE_CHANGESETAPPLY_IGNORENOOP    0x0004
 
 /*
 ** CAPI3REF: Constants Passed To The Conflict Handler
@@ -13522,8 +13628,8 @@ struct fts5_api {
 #endif
 
 /*
-** WAL mode depends on atomic aligned 32-bit loads and stores in a few
-** places.  The following macros try to make this explicit.
+** A few places in the code require atomic load/store of aligned
+** integer values.
 */
 #ifndef __has_extension
 # define __has_extension(x) 0     /* compatibility with non-clang compilers */
@@ -13579,15 +13685,22 @@ struct fts5_api {
 #endif
 
 /*
-** A macro to hint to the compiler that a function should not be
+** Macros to hint to the compiler that a function should or should not be
 ** inlined.
 */
 #if defined(__GNUC__)
 #  define SQLITE_NOINLINE  __attribute__((noinline))
+#  define SQLITE_INLINE    __attribute__((always_inline)) inline
 #elif defined(_MSC_VER) && _MSC_VER>=1310
 #  define SQLITE_NOINLINE  __declspec(noinline)
+#  define SQLITE_INLINE    __forceinline
 #else
 #  define SQLITE_NOINLINE
+#  define SQLITE_INLINE
+#endif
+#if defined(SQLITE_COVERAGE_TEST) || defined(__STRICT_ANSI__)
+# undef SQLITE_INLINE
+# define SQLITE_INLINE
 #endif
 
 /*
@@ -16548,6 +16661,10 @@ SQLITE_PRIVATE void sqlite3VdbeScanStatusCounters(Vdbe*, int, int, int);
 SQLITE_PRIVATE void sqlite3VdbePrintOp(FILE*, int, VdbeOp*);
 #endif
 
+#if defined(SQLITE_ENABLE_CURSOR_HINTS) && defined(SQLITE_DEBUG)
+SQLITE_PRIVATE int sqlite3CursorRangeHintExprCheck(Walker *pWalker, Expr *pExpr);
+#endif
+
 #endif /* SQLITE_VDBE_H */
 
 /************** End of vdbe.h ************************************************/
@@ -17257,7 +17374,7 @@ struct sqlite3 {
 #define SQLITE_NullCallback   0x00000100  /* Invoke the callback once if the */
                                           /*   result set is empty */
 #define SQLITE_IgnoreChecks   0x00000200  /* Do not enforce check constraints */
-#define SQLITE_ReadUncommit   0x00000400  /* READ UNCOMMITTED in shared-cache */
+#define SQLITE_StmtScanStatus 0x00000400  /* Enable stmt_scanstats() counters */
 #define SQLITE_NoCkptOnClose  0x00000800  /* No checkpoint on close()/DETACH */
 #define SQLITE_ReverseOrder   0x00001000  /* Reverse unordered SELECTs */
 #define SQLITE_RecTriggers    0x00002000  /* Enable recursive triggers */
@@ -17283,6 +17400,7 @@ struct sqlite3 {
                                           /*   DELETE, or UPDATE and return */
                                           /*   the count using a callback. */
 #define SQLITE_CorruptRdOnly  HI(0x00002) /* Prohibit writes due to error */
+#define SQLITE_ReadUncommit   HI(0x00004) /* READ UNCOMMITTED in shared-cache */
 
 /* Flags used only if debugging */
 #ifdef SQLITE_DEBUG
@@ -17339,6 +17457,7 @@ struct sqlite3 {
    /* TH3 expects this value  ^^^^^^^^^^ See flatten04.test */
 #define SQLITE_IndexedExpr    0x01000000 /* Pull exprs from index when able */
 #define SQLITE_Coroutines     0x02000000 /* Co-routines for subqueries */
+#define SQLITE_NullUnusedCols 0x04000000 /* NULL unused columns in subqueries */
 #define SQLITE_AllOpts        0xffffffff /* All optimizations */
 
 /*
@@ -17810,6 +17929,7 @@ struct VTable {
   sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
   int nRef;                 /* Number of pointers to this structure */
   u8 bConstraint;           /* True if constraints are supported */
+  u8 bAllSchemas;           /* True if might use any attached schema */
   u8 eVtabRisk;             /* Riskiness of allowing hacker access */
   int iSavepoint;           /* Depth of the SAVEPOINT stack */
   VTable *pNext;            /* Next in linked list (see above) */
@@ -18190,6 +18310,7 @@ struct Index {
                            ** expression, or a reference to a VIRTUAL column */
 #ifdef SQLITE_ENABLE_STAT4
   int nSample;             /* Number of elements in aSample[] */
+  int mxSample;            /* Number of slots allocated to aSample[] */
   int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
   tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
   IndexSample *aSample;    /* Samples of the left-most key */
@@ -19676,6 +19797,7 @@ struct Walker {
     struct CoveringIndexCheck *pCovIdxCk;     /* Check for covering index */
     SrcItem *pSrcItem;                        /* A single FROM clause item */
     DbFixer *pFix;                            /* See sqlite3FixSelect() */
+    Mem *aMem;                                /* See sqlite3BtreeCursorHint() */
   } u;
 };
 
@@ -19945,6 +20067,8 @@ SQLITE_PRIVATE   int sqlite3CorruptPgnoError(int,Pgno);
 # define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
 # define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
 # define sqlite3Isquote(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x80)
+# define sqlite3JsonId1(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x42)
+# define sqlite3JsonId2(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x46)
 #else
 # define sqlite3Toupper(x)   toupper((unsigned char)(x))
 # define sqlite3Isspace(x)   isspace((unsigned char)(x))
@@ -19954,6 +20078,8 @@ SQLITE_PRIVATE   int sqlite3CorruptPgnoError(int,Pgno);
 # define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
 # define sqlite3Tolower(x)   tolower((unsigned char)(x))
 # define sqlite3Isquote(x)   ((x)=='"'||(x)=='\''||(x)=='['||(x)=='`')
+# define sqlite3JsonId1(x)   (sqlite3IsIdChar(x)&&(x)<'0')
+# define sqlite3JsonId2(x)   sqlite3IsIdChar(x)
 #endif
 SQLITE_PRIVATE int sqlite3IsIdChar(u8);
 
@@ -20147,6 +20273,10 @@ SQLITE_PRIVATE void sqlite3ReleaseTempReg(Parse*,int);
 SQLITE_PRIVATE int sqlite3GetTempRange(Parse*,int);
 SQLITE_PRIVATE void sqlite3ReleaseTempRange(Parse*,int,int);
 SQLITE_PRIVATE void sqlite3ClearTempRegCache(Parse*);
+SQLITE_PRIVATE void sqlite3TouchRegister(Parse*,int);
+#if defined(SQLITE_ENABLE_STAT4) || defined(SQLITE_DEBUG)
+SQLITE_PRIVATE int sqlite3FirstAvailableRegister(Parse*,int);
+#endif
 #ifdef SQLITE_DEBUG
 SQLITE_PRIVATE int sqlite3NoTempsInRange(Parse*,int,int);
 #endif
@@ -20297,7 +20427,7 @@ SQLITE_PRIVATE Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList
                          Expr*,ExprList*,u32,Expr*);
 SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3*, Select*);
 SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse*, SrcList*);
-SQLITE_PRIVATE int sqlite3IsReadOnly(Parse*, Table*, int);
+SQLITE_PRIVATE int sqlite3IsReadOnly(Parse*, Table*, Trigger*);
 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*,char*);
@@ -20386,7 +20516,7 @@ SQLITE_PRIVATE int sqlite3ExprIsConstantNotJoin(Expr*);
 SQLITE_PRIVATE int sqlite3ExprIsConstantOrFunction(Expr*, u8);
 SQLITE_PRIVATE int sqlite3ExprIsConstantOrGroupBy(Parse*, Expr*, ExprList*);
 SQLITE_PRIVATE int sqlite3ExprIsTableConstant(Expr*,int);
-SQLITE_PRIVATE int sqlite3ExprIsTableConstraint(Expr*,const SrcItem*);
+SQLITE_PRIVATE int sqlite3ExprIsSingleTableConstraint(Expr*,const SrcList*,int);
 #ifdef SQLITE_ENABLE_CURSOR_HINTS
 SQLITE_PRIVATE int sqlite3ExprContainsSubquery(Expr*);
 #endif
@@ -20834,10 +20964,7 @@ SQLITE_PRIVATE int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
 SQLITE_PRIVATE int sqlite3VtabBegin(sqlite3 *, VTable *);
 
 SQLITE_PRIVATE FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
-#if (defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)) \
-    && !defined(SQLITE_OMIT_VIRTUALTABLE)
-SQLITE_PRIVATE   void sqlite3VtabUsesAllSchemas(sqlite3_index_info*);
-#endif
+SQLITE_PRIVATE void sqlite3VtabUsesAllSchemas(Parse*);
 SQLITE_PRIVATE sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
 SQLITE_PRIVATE int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
 SQLITE_PRIVATE int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
@@ -21084,6 +21211,12 @@ SQLITE_PRIVATE int sqlite3KvvfsInit(void);
 SQLITE_PRIVATE sqlite3_uint64 sqlite3Hwtime(void);
 #endif
 
+#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
+# define IS_STMT_SCANSTATUS(db) (db->flags & SQLITE_StmtScanStatus)
+#else
+# define IS_STMT_SCANSTATUS(db) 0
+#endif
+
 #endif /* SQLITEINT_H */
 
 /************** End of sqliteInt.h *******************************************/
@@ -22079,7 +22212,7 @@ SQLITE_PRIVATE const unsigned char *sqlite3aGTb = &sqlite3UpperToLower[256+12-OP
 **   isalnum()                        0x06
 **   isxdigit()                       0x08
 **   toupper()                        0x20
-**   SQLite identifier character      0x40
+**   SQLite identifier character      0x40   $, _, or non-ascii
 **   Quote character                  0x80
 **
 ** Bit 0x20 is set if the mapped character requires translation to upper
@@ -22273,7 +22406,7 @@ SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config = {
    SQLITE_DEFAULT_SORTERREF_SIZE,   /* szSorterRef */
    0,                         /* iPrngSeed */
 #ifdef SQLITE_DEBUG
-   {0,0,0,0,0,0}              /* aTune */
+   {0,0,0,0,0,0},             /* aTune */
 #endif
 };
 
@@ -23572,6 +23705,7 @@ struct DateTime {
   char validTZ;       /* True (1) if tz is valid */
   char tzSet;         /* Timezone was set explicitly */
   char isError;       /* An overflow has occurred */
+  char useSubsec;     /* Display subsecond precision */
 };
 
 
@@ -23886,6 +24020,11 @@ static int parseDateOrTime(
   }else if( sqlite3AtoF(zDate, &r, sqlite3Strlen30(zDate), SQLITE_UTF8)>0 ){
     setRawDateNumber(p, r);
     return 0;
+  }else if( (sqlite3StrICmp(zDate,"subsec")==0
+             || sqlite3StrICmp(zDate,"subsecond")==0)
+           && sqlite3NotPureFunc(context) ){
+    p->useSubsec = 1;
+    return setDateTimeToCurrent(context, p);
   }
   return 1;
 }
@@ -24300,8 +24439,22 @@ static int parseModifier(
       **
       ** Move the date backwards to the beginning of the current day,
       ** or month or year.
+      **
+      **    subsecond
+      **    subsec
+      **
+      ** Show subsecond precision in the output of datetime() and
+      ** unixepoch() and strftime('%s').
       */
-      if( sqlite3_strnicmp(z, "start of ", 9)!=0 ) break;
+      if( sqlite3_strnicmp(z, "start of ", 9)!=0 ){
+        if( sqlite3_stricmp(z, "subsec")==0
+         || sqlite3_stricmp(z, "subsecond")==0
+        ){
+          p->useSubsec = 1;
+          rc = 0;
+        }
+        break;
+      }
       if( !p->validJD && !p->validYMD && !p->validHMS ) break;
       z += 9;
       computeYMD(p);
@@ -24499,7 +24652,11 @@ static void unixepochFunc(
   DateTime x;
   if( isDate(context, argc, argv, &x)==0 ){
     computeJD(&x);
-    sqlite3_result_int64(context, x.iJD/1000 - 21086676*(i64)10000);
+    if( x.useSubsec ){
+      sqlite3_result_double(context, (x.iJD - 21086676*(i64)10000000)/1000.0);
+    }else{
+      sqlite3_result_int64(context, x.iJD/1000 - 21086676*(i64)10000);
+    }
   }
 }
 
@@ -24515,8 +24672,8 @@ static void datetimeFunc(
 ){
   DateTime x;
   if( isDate(context, argc, argv, &x)==0 ){
-    int Y, s;
-    char zBuf[24];
+    int Y, s, n;
+    char zBuf[32];
     computeYMD_HMS(&x);
     Y = x.Y;
     if( Y<0 ) Y = -Y;
@@ -24537,15 +24694,28 @@ static void datetimeFunc(
     zBuf[15] = '0' + (x.m/10)%10;
     zBuf[16] = '0' + (x.m)%10;
     zBuf[17] = ':';
-    s = (int)x.s;
-    zBuf[18] = '0' + (s/10)%10;
-    zBuf[19] = '0' + (s)%10;
-    zBuf[20] = 0;
+    if( x.useSubsec ){
+      s = (int)1000.0*x.s;
+      zBuf[18] = '0' + (s/10000)%10;
+      zBuf[19] = '0' + (s/1000)%10;
+      zBuf[20] = '.';
+      zBuf[21] = '0' + (s/100)%10;
+      zBuf[22] = '0' + (s/10)%10;
+      zBuf[23] = '0' + (s)%10;
+      zBuf[24] = 0;
+      n = 24;
+    }else{
+      s = (int)x.s;
+      zBuf[18] = '0' + (s/10)%10;
+      zBuf[19] = '0' + (s)%10;
+      zBuf[20] = 0;
+      n = 20;
+    }
     if( x.Y<0 ){
       zBuf[0] = '-';
-      sqlite3_result_text(context, zBuf, 20, SQLITE_TRANSIENT);
+      sqlite3_result_text(context, zBuf, n, SQLITE_TRANSIENT);
     }else{
-      sqlite3_result_text(context, &zBuf[1], 19, SQLITE_TRANSIENT);
+      sqlite3_result_text(context, &zBuf[1], n-1, SQLITE_TRANSIENT);
     }
   }
 }
@@ -24562,7 +24732,7 @@ static void timeFunc(
 ){
   DateTime x;
   if( isDate(context, argc, argv, &x)==0 ){
-    int s;
+    int s, n;
     char zBuf[16];
     computeHMS(&x);
     zBuf[0] = '0' + (x.h/10)%10;
@@ -24571,11 +24741,24 @@ static void timeFunc(
     zBuf[3] = '0' + (x.m/10)%10;
     zBuf[4] = '0' + (x.m)%10;
     zBuf[5] = ':';
-    s = (int)x.s;
-    zBuf[6] = '0' + (s/10)%10;
-    zBuf[7] = '0' + (s)%10;
-    zBuf[8] = 0;
-    sqlite3_result_text(context, zBuf, 8, SQLITE_TRANSIENT);
+    if( x.useSubsec ){
+      s = (int)1000.0*x.s;
+      zBuf[6] = '0' + (s/10000)%10;
+      zBuf[7] = '0' + (s/1000)%10;
+      zBuf[8] = '.';
+      zBuf[9] = '0' + (s/100)%10;
+      zBuf[10] = '0' + (s/10)%10;
+      zBuf[11] = '0' + (s)%10;
+      zBuf[12] = 0;
+      n = 12;
+    }else{
+      s = (int)x.s;
+      zBuf[6] = '0' + (s/10)%10;
+      zBuf[7] = '0' + (s)%10;
+      zBuf[8] = 0;
+      n = 8;
+    }
+    sqlite3_result_text(context, zBuf, n, SQLITE_TRANSIENT);
   }
 }
 
@@ -24706,8 +24889,13 @@ static void strftimeFunc(
         break;
       }
       case 's': {
-        i64 iS = (i64)(x.iJD/1000 - 21086676*(i64)10000);
-        sqlite3_str_appendf(&sRes,"%lld",iS);
+        if( x.useSubsec ){
+          sqlite3_str_appendf(&sRes,"%.3f",
+                (x.iJD - 21086676*(i64)10000000)/1000.0);
+        }else{
+          i64 iS = (i64)(x.iJD/1000 - 21086676*(i64)10000);
+          sqlite3_str_appendf(&sRes,"%lld",iS);
+        }
         break;
       }
       case 'S': {
@@ -30078,6 +30266,20 @@ static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
 }
 #endif /* SQLITE_OMIT_FLOATING_POINT */
 
+#ifndef SQLITE_OMIT_FLOATING_POINT
+/*
+** "*val" is a u64.  *msd is a divisor used to extract the
+** most significant digit of *val.  Extract that most significant
+** digit and return it.
+*/
+static char et_getdigit_int(u64 *val, u64 *msd){
+  u64 x = (*val)/(*msd);
+  *val -= x*(*msd);
+  if( *msd>=10 ) *msd /= 10;
+  return '0' + (char)(x & 15);
+}
+#endif /* SQLITE_OMIT_FLOATING_POINT */
+
 /*
 ** Set the StrAccum object to an error mode.
 */
@@ -30170,6 +30372,8 @@ SQLITE_API void sqlite3_str_vappendf(
   char prefix;               /* Prefix character.  "+" or "-" or " " or '\0'. */
   sqlite_uint64 longvalue;   /* Value for integer types */
   LONGDOUBLE_TYPE realvalue; /* Value for real types */
+  sqlite_uint64 msd;         /* Divisor to get most-significant-digit
+                             ** of longvalue */
   const et_info *infop;      /* Pointer to the appropriate info structure */
   char *zOut;                /* Rendering buffer */
   int nOut;                  /* Size of the rendering buffer */
@@ -30476,52 +30680,78 @@ SQLITE_API void sqlite3_str_vappendf(
         }else{
           prefix = flag_prefix;
         }
+        exp = 0;
         if( xtype==etGENERIC && precision>0 ) precision--;
         testcase( precision>0xfff );
-        idx = precision & 0xfff;
-        rounder = arRound[idx%10];
-        while( idx>=10 ){ rounder *= 1.0e-10; idx -= 10; }
-        if( xtype==etFLOAT ){
-          double rx = (double)realvalue;
-          sqlite3_uint64 u;
-          int ex;
-          memcpy(&u, &rx, sizeof(u));
-          ex = -1023 + (int)((u>>52)&0x7ff);
-          if( precision+(ex/3) < 15 ) rounder += realvalue*3e-16;
-          realvalue += rounder;
-        }
-        /* Normalize realvalue to within 10.0 > realvalue >= 1.0 */
-        exp = 0;
-        if( sqlite3IsNaN((double)realvalue) ){
-          bufpt = "NaN";
-          length = 3;
-          break;
-        }
-        if( realvalue>0.0 ){
-          LONGDOUBLE_TYPE scale = 1.0;
-          while( realvalue>=1e100*scale && exp<=350 ){ scale *= 1e100;exp+=100;}
-          while( realvalue>=1e10*scale && exp<=350 ){ scale *= 1e10; exp+=10; }
-          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 ){
-            bufpt = buf;
-            buf[0] = prefix;
-            memcpy(buf+(prefix!=0),"Inf",4);
-            length = 3+(prefix!=0);
+        if( realvalue<1.0e+16
+         && realvalue==(LONGDOUBLE_TYPE)(longvalue = (u64)realvalue)
+        ){
+          /* Number is a pure integer that can be represented as u64 */
+          for(msd=1; msd*10<=longvalue; msd *= 10, exp++){}
+          if( exp>precision && xtype!=etFLOAT ){
+            u64 rnd = msd/2;
+            int kk = precision;
+            while( kk-- > 0 ){  rnd /= 10; }
+            longvalue += rnd;
+          }
+        }else{
+          msd = 0;
+          longvalue = 0;  /* To prevent a compiler warning */
+          idx = precision & 0xfff;
+          rounder = arRound[idx%10];
+          while( idx>=10 ){ rounder *= 1.0e-10; idx -= 10; }
+          if( xtype==etFLOAT ){
+            double rx = (double)realvalue;
+            sqlite3_uint64 u;
+            int ex;
+            memcpy(&u, &rx, sizeof(u));
+            ex = -1023 + (int)((u>>52)&0x7ff);
+            if( precision+(ex/3) < 15 ) rounder += realvalue*3e-16;
+            realvalue += rounder;