Wapp

**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.40.0"
#define SQLITE_VERSION_NUMBER 3040000
#define SQLITE_SOURCE_ID      "2022-11-07 19:40:20 55a19677d723147aeb2b4a86bbd01756ddeb2072cba72c3145ad32d335e203b0"

/*
** CAPI3REF: Run-Time Library Version Numbers
** KEYWORDS: sqlite3_version sqlite3_sourceid
**
** These interfaces provide the same information as the [SQLITE_VERSION],
** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros

#define SQLITE_IOCAP_BATCH_ATOMIC           0x00004000

/*
** CAPI3REF: File Locking Levels
**
** SQLite uses one of these integer values as the second
** argument to calls it makes to the xLock() and xUnlock() methods
** of an [sqlite3_io_methods] object.  These values are ordered from
** lest restrictive to most restrictive.
**
** The argument to xLock() is always SHARED or higher.  The argument to
** xUnlock is either SHARED or NONE.
*/
#define SQLITE_LOCK_NONE          0       /* xUnlock() only */
#define SQLITE_LOCK_SHARED        1       /* xLock() or xUnlock() */
#define SQLITE_LOCK_RESERVED      2       /* xLock() only */
#define SQLITE_LOCK_PENDING       3       /* xLock() only */
#define SQLITE_LOCK_EXCLUSIVE     4       /* xLock() only */

/*
** CAPI3REF: Synchronization Type Flags
**
** When SQLite invokes the xSync() method of an
** [sqlite3_io_methods] object it uses a combination of
** these integer values as the second argument.

** <ul>
** <li> [SQLITE_LOCK_NONE],
** <li> [SQLITE_LOCK_SHARED],
** <li> [SQLITE_LOCK_RESERVED],
** <li> [SQLITE_LOCK_PENDING], or
** <li> [SQLITE_LOCK_EXCLUSIVE].
** </ul>
** xLock() upgrades the database file lock.  In other words, xLock() moves the
** database file lock in the direction NONE toward EXCLUSIVE. The argument to
** xLock() is always on of SHARED, RESERVED, PENDING, or EXCLUSIVE, never
** SQLITE_LOCK_NONE.  If the database file lock is already at or above the
** requested lock, then the call to xLock() is a no-op.
** xUnlock() downgrades the database file lock to either SHARED or NONE.
*  If the lock is already at or below the requested lock state, then the call
** to xUnlock() is a no-op.
** The xCheckReservedLock() method checks whether any database connection,
** either in this process or in some other process, is holding a RESERVED,
** PENDING, or EXCLUSIVE lock on the file.  It returns true
** if such a lock exists and false otherwise.
**
** The xFileControl() method is a generic interface that allows custom
** VFS implementations to directly control an open file using the

**
** <ul>
** <li>[[SQLITE_FCNTL_LOCKSTATE]]
** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging.  This
** opcode causes the xFileControl method to write the current state of
** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],
** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])
** into an integer that the pArg argument points to.
** This capability is only available if SQLite is compiled with [SQLITE_DEBUG].

**
** <li>[[SQLITE_FCNTL_SIZE_HINT]]
** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS
** layer a hint of how large the database file will grow to be during the
** current transaction.  This hint is not guaranteed to be accurate but it
** is often close.  The underlying VFS might choose to preallocate database
** file space based on this hint in order to help writes to the database

** A pointer to the opaque sqlite3_api_routines structure is passed as
** the third parameter to entry points of [loadable extensions].  This
** structure must be typedefed in order to work around compiler warnings
** on some platforms.
*/
typedef struct sqlite3_api_routines sqlite3_api_routines;

/*
** CAPI3REF: File Name
**
** Type [sqlite3_filename] is used by SQLite to pass filenames to the
** xOpen method of a [VFS]. It may be cast to (const char*) and treated
** as a normal, nul-terminated, UTF-8 buffer containing the filename, but
** may also be passed to special APIs such as:
**
** <ul>
** <li>  sqlite3_filename_database()
** <li>  sqlite3_filename_journal()
** <li>  sqlite3_filename_wal()
** <li>  sqlite3_uri_parameter()
** <li>  sqlite3_uri_boolean()
** <li>  sqlite3_uri_int64()
** <li>  sqlite3_uri_key()
** </ul>
*/
typedef const char *sqlite3_filename;

/*
** CAPI3REF: OS Interface Object
**
** An instance of the sqlite3_vfs object defines the interface between
** the SQLite core and the underlying operating system.  The "vfs"
** in the name of the object stands for "virtual file system".  See
** the [VFS | VFS documentation] for further information.

struct sqlite3_vfs {
  int iVersion;            /* Structure version number (currently 3) */
  int szOsFile;            /* Size of subclassed sqlite3_file */
  int mxPathname;          /* Maximum file pathname length */
  sqlite3_vfs *pNext;      /* Next registered VFS */
  const char *zName;       /* Name of this virtual file system */
  void *pAppData;          /* Pointer to application-specific data */
  int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*,
               int flags, int *pOutFlags);
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut);
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut);
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
  void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void);

** routines would only work if F was the name of the main database file.
** When the F parameter is the name of the rollback journal or WAL file,
** it has access to all the same query parameters as were found on the
** main database file.
**
** See the [URI filename] documentation for additional information.
*/
SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam);
SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault);
SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64);
SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N);

/*
** CAPI3REF:  Translate filenames
**
** These routines are available to [VFS|custom VFS implementations] for
** translating filenames between the main database file, the journal file,
** and the WAL file.

** WAL file.
**
** In all of the above, if F is not the name of a database, journal or WAL
** filename passed into the VFS from the SQLite core and F is not the
** return value from [sqlite3_db_filename()], then the result is
** undefined and is likely a memory access violation.
*/
SQLITE_API const char *sqlite3_filename_database(sqlite3_filename);
SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename);
SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename);

/*
** CAPI3REF:  Database File Corresponding To A Journal
**
** ^If X is the name of a rollback or WAL-mode journal file that is
** passed into the xOpen method of [sqlite3_vfs], then
** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file]

** sqlite3_create_filename(), then bad things such as heap
** corruption or segfaults may occur. The value Y should not be
** used again after sqlite3_free_filename(Y) has been called.  This means
** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y,
** then the corresponding [sqlite3_module.xClose() method should also be
** invoked prior to calling sqlite3_free_filename(Y).
*/
SQLITE_API sqlite3_filename sqlite3_create_filename(
  const char *zDatabase,
  const char *zJournal,
  const char *zWal,
  int nParam,
  const char **azParam
);
SQLITE_API void sqlite3_free_filename(sqlite3_filename);

/*
** CAPI3REF: Error Codes And Messages
** METHOD: sqlite3
**
** ^If the most recent sqlite3_* API call associated with
** [database connection] D failed, then the sqlite3_errcode(D) interface

** numeric affinity to the value.  This means that an attempt is
** made to convert the value to an integer or floating point.  If
** such a conversion is possible without loss of information (in other
** words, if the value is a string that looks like a number)
** then the conversion is performed.  Otherwise no conversion occurs.
** The [SQLITE_INTEGER | datatype] after conversion is returned.)^
**
** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8],
** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current encoding
** of the value X, assuming that X has type TEXT.)^  If sqlite3_value_type(X)
** returns something other than SQLITE_TEXT, then the return value from
** sqlite3_value_encoding(X) is meaningless.  ^Calls to
** sqlite3_value_text(X), sqlite3_value_text16(X), sqlite3_value_text16be(X),
** sqlite3_value_text16le(X), sqlite3_value_bytes(X), or
** sqlite3_value_bytes16(X) might change the encoding of the value X and
** thus change the return from subsequent calls to sqlite3_value_encoding(X).
**
** ^Within the [xUpdate] method of a [virtual table], the
** sqlite3_value_nochange(X) interface returns true if and only if
** the column corresponding to X is unchanged by the UPDATE operation
** that the xUpdate method call was invoked to implement and if
** and the prior [xColumn] method call that was invoked to extracted
** the value for that column returned without setting a result (probably
** because it queried [sqlite3_vtab_nochange()] and found that the column

SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*);
SQLITE_API int sqlite3_value_bytes(sqlite3_value*);
SQLITE_API int sqlite3_value_bytes16(sqlite3_value*);
SQLITE_API int sqlite3_value_type(sqlite3_value*);
SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*);
SQLITE_API int sqlite3_value_nochange(sqlite3_value*);
SQLITE_API int sqlite3_value_frombind(sqlite3_value*);
SQLITE_API int sqlite3_value_encoding(sqlite3_value*);

/*
** CAPI3REF: Finding The Subtype Of SQL Values
** METHOD: sqlite3_value
**
** The sqlite3_value_subtype(V) function returns the subtype for
** an [application-defined SQL function] argument V.  The subtype

** an aggregate query, the xStep() callback of the aggregate function
** implementation is never called and xFinal() is called exactly once.
** 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
** when first called if N is less than or equal to zero or if a memory
** allocation 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 any subsequent call to sqlite3_aggregate_context() within
** the same aggregate function instance will not resize the memory
** allocation.)^  Within the xFinal callback, it is customary to set
** N=0 in calls to sqlite3_aggregate_context(C,N) so that no

** UTF-16 little endian, or UTF-16 big endian, respectively.
** ^The sqlite3_result_text64() interface sets the return value of an
** application-defined function to be a text string in an encoding
** specified by the fifth (and last) parameter, which must be one
** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].
** ^SQLite takes the text result from the application from
** the 2nd parameter of the sqlite3_result_text* interfaces.
** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces
** other than sqlite3_result_text64() is negative, then SQLite computes
** the string length itself by searching the 2nd parameter for the first
** zero character.
** ^If the 3rd parameter to the sqlite3_result_text* interfaces
** is non-negative, then as many bytes (not characters) of the text
** pointed to by the 2nd parameter are taken as the application-defined
** function result.  If the 3rd parameter is non-negative, then it
** must be the byte offset into the string where the NUL terminator would
** appear if the string where NUL terminated.  If any NUL characters occur
** in the string at a byte offset that is less than the value of the 3rd

** <li> [sqlite3_uri_boolean()]
** <li> [sqlite3_uri_int64()]
** <li> [sqlite3_filename_database()]
** <li> [sqlite3_filename_journal()]
** <li> [sqlite3_filename_wal()]
** </ul>
*/
SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName);

/*
** CAPI3REF: Determine if a database is read-only
** METHOD: sqlite3
**
** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N
** of connection D is read-only, 0 if it is read/write, or -1 if N is not

#define SQLITE_MUTEX_STATIC_TEMPDIR SQLITE_MUTEX_STATIC_VFS1

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
*/
#if defined(_HAVE_SQLITE_CONFIG_H) && !defined(SQLITECONFIG_H)
#include "sqlite_cfg.h"
#define SQLITECONFIG_H 1
#endif

/************** Include sqliteLimit.h in the middle of sqliteInt.h ***********/
/************** Begin file sqliteLimit.h *************************************/
/*
** 2007 May 7

typedef struct ExprList ExprList;
typedef struct FKey FKey;
typedef struct FuncDestructor FuncDestructor;
typedef struct FuncDef FuncDef;
typedef struct FuncDefHash FuncDefHash;
typedef struct IdList IdList;
typedef struct Index Index;
typedef struct IndexedExpr IndexedExpr;
typedef struct IndexSample IndexSample;
typedef struct KeyClass KeyClass;
typedef struct KeyInfo KeyInfo;
typedef struct Lookaside Lookaside;
typedef struct LookasideSlot LookasideSlot;
typedef struct Module Module;
typedef struct NameContext NameContext;

** A bit in a Bitmask
*/
#define MASKBIT(n)    (((Bitmask)1)<<(n))
#define MASKBIT64(n)  (((u64)1)<<(n))
#define MASKBIT32(n)  (((unsigned int)1)<<(n))
#define SMASKBIT32(n) ((n)<=31?((unsigned int)1)<<(n):0)
#define ALLBITS       ((Bitmask)-1)
#define TOPBIT        (((Bitmask)1)<<(BMS-1))

/* A VList object records a mapping between parameters/variables/wildcards
** in the SQL statement (such as $abc, @pqr, or :xyz) and the integer
** variable number associated with that parameter.  See the format description
** on the sqlite3VListAdd() routine for more information.  A VList is really
** just an array of integers.
*/
typedef int VList;

/*
** Defer sourcing vdbe.h and btree.h until after the "u8" and
** "BusyHandler" typedefs. vdbe.h also requires a few of the opaque
** pointer types (i.e. FuncDef) defined above.
*/
/************** Include os.h in the middle of sqliteInt.h ********************/
/************** Begin file os.h **********************************************/
/*
** 2001 September 16
**
** 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 header file (together with is companion C source-code file
** "os.c") attempt to abstract the underlying operating system so that
** the SQLite library will work on both POSIX and windows systems.
**
** This header file is #include-ed by sqliteInt.h and thus ends up
** being included by every source file.
*/
#ifndef _SQLITE_OS_H_
#define _SQLITE_OS_H_

/*
** Attempt to automatically detect the operating system and setup the
** necessary pre-processor macros for it.
*/
/************** Include os_setup.h in the middle of os.h *********************/
/************** Begin file os_setup.h ****************************************/
/*
** 2013 November 25
**
** 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 pre-processor directives related to operating system
** detection and/or setup.
*/
#ifndef SQLITE_OS_SETUP_H
#define SQLITE_OS_SETUP_H

/*
** 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_KV
**    SQLITE_OS_OTHER
**    SQLITE_OS_UNIX
**    SQLITE_OS_WIN
**
** will defined to either 1 or 0. One of them will be 1. The others will be 0.
** If none of the macros are initially defined, then select either
** SQLITE_OS_UNIX or SQLITE_OS_WIN depending on the target platform.
**
** If SQLITE_OS_OTHER=1 is specified at compile-time, then the application
** must provide its own VFS implementation together with sqlite3_os_init()
** and sqlite3_os_end() routines.
*/
#if !defined(SQLITE_OS_KV) && !defined(SQLITE_OS_OTHER) && \
       !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_WIN)
#  if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || \
          defined(__MINGW32__) || defined(__BORLANDC__)
#    define SQLITE_OS_WIN 1
#    define SQLITE_OS_UNIX 0
#  else
#    define SQLITE_OS_WIN 0
#    define SQLITE_OS_UNIX 1
#  endif
#endif
#if SQLITE_OS_OTHER+1>1
#  undef SQLITE_OS_KV
#  define SQLITE_OS_KV 0
#  undef SQLITE_OS_UNIX
#  define SQLITE_OS_UNIX 0
#  undef SQLITE_OS_WIN
#  define SQLITE_OS_WIN 0
#endif
#if SQLITE_OS_KV+1>1
#  undef SQLITE_OS_OTHER
#  define SQLITE_OS_OTHER 0
#  undef SQLITE_OS_UNIX
#  define SQLITE_OS_UNIX 0
#  undef SQLITE_OS_WIN
#  define SQLITE_OS_WIN 0
#  define SQLITE_OMIT_LOAD_EXTENSION 1
#  define SQLITE_OMIT_WAL 1
#  define SQLITE_OMIT_DEPRECATED 1
#  undef SQLITE_TEMP_STORE
#  define SQLITE_TEMP_STORE 3  /* Always use memory for temporary storage */
#  define SQLITE_DQS 0
#  define SQLITE_OMIT_SHARED_CACHE 1
#  define SQLITE_OMIT_AUTOINIT 1
#endif
#if SQLITE_OS_UNIX+1>1
#  undef SQLITE_OS_KV
#  define SQLITE_OS_KV 0
#  undef SQLITE_OS_OTHER
#  define SQLITE_OS_OTHER 0
#  undef SQLITE_OS_WIN
#  define SQLITE_OS_WIN 0
#endif
#if SQLITE_OS_WIN+1>1
#  undef SQLITE_OS_KV
#  define SQLITE_OS_KV 0
#  undef SQLITE_OS_OTHER
#  define SQLITE_OS_OTHER 0
#  undef SQLITE_OS_UNIX
#  define SQLITE_OS_UNIX 0
#endif


#endif /* SQLITE_OS_SETUP_H */

/************** End of os_setup.h ********************************************/
/************** Continuing where we left off in os.h *************************/

/* If the SET_FULLSYNC macro is not defined above, then make it
** a no-op
*/
#ifndef SET_FULLSYNC
# define SET_FULLSYNC(x,y)
#endif

/* Maximum pathname length.  Note: FILENAME_MAX defined by stdio.h
*/
#ifndef SQLITE_MAX_PATHLEN
# define SQLITE_MAX_PATHLEN FILENAME_MAX
#endif

/* Maximum number of symlinks that will be resolved while trying to
** expand a filename in xFullPathname() in the VFS.
*/
#ifndef SQLITE_MAX_SYMLINK
# define SQLITE_MAX_SYMLINK 200
#endif

/*
** The default size of a disk sector
*/
#ifndef SQLITE_DEFAULT_SECTOR_SIZE
# define SQLITE_DEFAULT_SECTOR_SIZE 4096
#endif

/*
** Temporary files are named starting with this prefix followed by 16 random
** alphanumeric characters, and no file extension. They are stored in the
** OS's standard temporary file directory, and are deleted prior to exit.
** If sqlite is being embedded in another program, you may wish to change the
** prefix to reflect your program's name, so that if your program exits
** prematurely, old temporary files can be easily identified. This can be done
** using -DSQLITE_TEMP_FILE_PREFIX=myprefix_ on the compiler command line.
**
** 2006-10-31:  The default prefix used to be "sqlite_".  But then
** Mcafee started using SQLite in their anti-virus product and it
** started putting files with the "sqlite" name in the c:/temp folder.
** This annoyed many windows users.  Those users would then do a
** Google search for "sqlite", find the telephone numbers of the
** developers and call to wake them up at night and complain.
** For this reason, the default name prefix is changed to be "sqlite"
** spelled backwards.  So the temp files are still identified, but
** anybody smart enough to figure out the code is also likely smart
** enough to know that calling the developer will not help get rid
** of the file.
*/
#ifndef SQLITE_TEMP_FILE_PREFIX
# define SQLITE_TEMP_FILE_PREFIX "etilqs_"
#endif

/*
** The following values may be passed as the second argument to
** sqlite3OsLock(). The various locks exhibit the following semantics:
**
** SHARED:    Any number of processes may hold a SHARED lock simultaneously.
** RESERVED:  A single process may hold a RESERVED lock on a file at
**            any time. Other processes may hold and obtain new SHARED locks.
** PENDING:   A single process may hold a PENDING lock on a file at
**            any one time. Existing SHARED locks may persist, but no new
**            SHARED locks may be obtained by other processes.
** EXCLUSIVE: An EXCLUSIVE lock precludes all other locks.
**
** PENDING_LOCK may not be passed directly to sqlite3OsLock(). Instead, a
** process that requests an EXCLUSIVE lock may actually obtain a PENDING
** lock. This can be upgraded to an EXCLUSIVE lock by a subsequent call to
** sqlite3OsLock().
*/
#define NO_LOCK         0
#define SHARED_LOCK     1
#define RESERVED_LOCK   2
#define PENDING_LOCK    3
#define EXCLUSIVE_LOCK  4

/*
** File Locking Notes:  (Mostly about windows but also some info for Unix)
**
** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
** those functions are not available.  So we use only LockFile() and
** UnlockFile().
**
** LockFile() prevents not just writing but also reading by other processes.
** A SHARED_LOCK is obtained by locking a single randomly-chosen
** byte out of a specific range of bytes. The lock byte is obtained at
** random so two separate readers can probably access the file at the
** same time, unless they are unlucky and choose the same lock byte.
** An EXCLUSIVE_LOCK is obtained by locking all bytes in the range.
** There can only be one writer.  A RESERVED_LOCK is obtained by locking
** a single byte of the file that is designated as the reserved lock byte.
** A PENDING_LOCK is obtained by locking a designated byte different from
** the RESERVED_LOCK byte.
**
** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
** which means we can use reader/writer locks.  When reader/writer locks
** are used, the lock is placed on the same range of bytes that is used
** for probabilistic locking in Win95/98/ME.  Hence, the locking scheme
** will support two or more Win95 readers or two or more WinNT readers.
** But a single Win95 reader will lock out all WinNT readers and a single
** WinNT reader will lock out all other Win95 readers.
**
** The following #defines specify the range of bytes used for locking.
** SHARED_SIZE is the number of bytes available in the pool from which
** a random byte is selected for a shared lock.  The pool of bytes for
** shared locks begins at SHARED_FIRST.
**
** The same locking strategy and
** byte ranges are used for Unix.  This leaves open the possibility of having
** clients on win95, winNT, and unix all talking to the same shared file
** and all locking correctly.  To do so would require that samba (or whatever
** tool is being used for file sharing) implements locks correctly between
** windows and unix.  I'm guessing that isn't likely to happen, but by
** using the same locking range we are at least open to the possibility.
**
** Locking in windows is manditory.  For this reason, we cannot store
** actual data in the bytes used for locking.  The pager never allocates
** the pages involved in locking therefore.  SHARED_SIZE is selected so
** that all locks will fit on a single page even at the minimum page size.
** PENDING_BYTE defines the beginning of the locks.  By default PENDING_BYTE
** is set high so that we don't have to allocate an unused page except
** for very large databases.  But one should test the page skipping logic
** by setting PENDING_BYTE low and running the entire regression suite.
**
** Changing the value of PENDING_BYTE results in a subtly incompatible
** file format.  Depending on how it is changed, you might not notice
** the incompatibility right away, even running a full regression test.
** The default location of PENDING_BYTE is the first byte past the
** 1GB boundary.
**
*/
#ifdef SQLITE_OMIT_WSD
# define PENDING_BYTE     (0x40000000)
#else
# define PENDING_BYTE      sqlite3PendingByte
#endif
#define RESERVED_BYTE     (PENDING_BYTE+1)
#define SHARED_FIRST      (PENDING_BYTE+2)
#define SHARED_SIZE       510

/*
** Wrapper around OS specific sqlite3_os_init() function.
*/
SQLITE_PRIVATE int sqlite3OsInit(void);

/*
** Functions for accessing sqlite3_file methods
*/
SQLITE_PRIVATE void sqlite3OsClose(sqlite3_file*);
SQLITE_PRIVATE int sqlite3OsRead(sqlite3_file*, void*, int amt, i64 offset);
SQLITE_PRIVATE int sqlite3OsWrite(sqlite3_file*, const void*, int amt, i64 offset);
SQLITE_PRIVATE int sqlite3OsTruncate(sqlite3_file*, i64 size);
SQLITE_PRIVATE int sqlite3OsSync(sqlite3_file*, int);
SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file*, i64 *pSize);
SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file*, int);
SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file*, int);
SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut);
SQLITE_PRIVATE int sqlite3OsFileControl(sqlite3_file*,int,void*);
SQLITE_PRIVATE void sqlite3OsFileControlHint(sqlite3_file*,int,void*);
#define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
SQLITE_PRIVATE int sqlite3OsSectorSize(sqlite3_file *id);
SQLITE_PRIVATE int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
#ifndef SQLITE_OMIT_WAL
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);
#endif /* SQLITE_OMIT_WAL */
SQLITE_PRIVATE int sqlite3OsFetch(sqlite3_file *id, i64, int, void **);
SQLITE_PRIVATE int sqlite3OsUnfetch(sqlite3_file *, i64, void *);


/*
** Functions for accessing sqlite3_vfs methods
*/
SQLITE_PRIVATE int sqlite3OsOpen(sqlite3_vfs *, const char *, sqlite3_file*, int, int *);
SQLITE_PRIVATE int sqlite3OsDelete(sqlite3_vfs *, const char *, int);
SQLITE_PRIVATE int sqlite3OsAccess(sqlite3_vfs *, const char *, int, int *pResOut);
SQLITE_PRIVATE int sqlite3OsFullPathname(sqlite3_vfs *, const char *, int, char *);
#ifndef SQLITE_OMIT_LOAD_EXTENSION
SQLITE_PRIVATE void *sqlite3OsDlOpen(sqlite3_vfs *, const char *);
SQLITE_PRIVATE void sqlite3OsDlError(sqlite3_vfs *, int, char *);
SQLITE_PRIVATE void (*sqlite3OsDlSym(sqlite3_vfs *, void *, const char *))(void);
SQLITE_PRIVATE void sqlite3OsDlClose(sqlite3_vfs *, void *);
#endif /* SQLITE_OMIT_LOAD_EXTENSION */
SQLITE_PRIVATE int sqlite3OsRandomness(sqlite3_vfs *, int, char *);
SQLITE_PRIVATE int sqlite3OsSleep(sqlite3_vfs *, int);
SQLITE_PRIVATE int sqlite3OsGetLastError(sqlite3_vfs*);
SQLITE_PRIVATE int sqlite3OsCurrentTimeInt64(sqlite3_vfs *, sqlite3_int64*);

/*
** Convenience functions for opening and closing files using
** sqlite3_malloc() to obtain space for the file-handle structure.
*/
SQLITE_PRIVATE int sqlite3OsOpenMalloc(sqlite3_vfs *, const char *, sqlite3_file **, int,int*);
SQLITE_PRIVATE void sqlite3OsCloseFree(sqlite3_file *);

#endif /* _SQLITE_OS_H_ */

/************** End of os.h **************************************************/
/************** Continuing where we left off in sqliteInt.h ******************/
/************** Include pager.h in the middle of sqliteInt.h *****************/
/************** Begin file pager.h *******************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:

#define OP_InitCoroutine  11 /* jump                                       */
#define OP_Yield          12 /* jump                                       */
#define OP_MustBeInt      13 /* jump                                       */
#define OP_Jump           14 /* jump                                       */
#define OP_Once           15 /* jump                                       */
#define OP_If             16 /* jump                                       */
#define OP_IfNot          17 /* jump                                       */
#define OP_IsType         18 /* jump, synopsis: if typeof(P1.P3) in P5 goto P2 */
#define OP_Not            19 /* same as TK_NOT, synopsis: r[P2]= !r[P1]    */
#define OP_IfNullRow      20 /* jump, synopsis: if P1.nullRow then r[P3]=NULL, goto P2 */
#define OP_SeekLT         21 /* jump, synopsis: key=r[P3@P4]               */
#define OP_SeekLE         22 /* jump, synopsis: key=r[P3@P4]               */
#define OP_SeekGE         23 /* jump, synopsis: key=r[P3@P4]               */
#define OP_SeekGT         24 /* jump, synopsis: key=r[P3@P4]               */
#define OP_IfNotOpen      25 /* jump, synopsis: if( !csr[P1] ) goto P2     */

#define OPFLG_IN2         0x04  /* in2:   P2 is an input */
#define OPFLG_IN3         0x08  /* in3:   P3 is an input */
#define OPFLG_OUT2        0x10  /* out2:  P2 is an output */
#define OPFLG_OUT3        0x20  /* out3:  P3 is an output */
#define OPFLG_INITIALIZER {\
/*   0 */ 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x01, 0x00,\
/*   8 */ 0x01, 0x01, 0x01, 0x01, 0x03, 0x03, 0x01, 0x01,\
/*  16 */ 0x03, 0x03, 0x01, 0x12, 0x01, 0x09, 0x09, 0x09,\
/*  24 */ 0x09, 0x01, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09,\
/*  32 */ 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,\
/*  40 */ 0x01, 0x01, 0x01, 0x26, 0x26, 0x01, 0x23, 0x0b,\
/*  48 */ 0x01, 0x01, 0x03, 0x03, 0x0b, 0x0b, 0x0b, 0x0b,\
/*  56 */ 0x0b, 0x0b, 0x01, 0x03, 0x03, 0x03, 0x01, 0x01,\
/*  64 */ 0x01, 0x00, 0x00, 0x02, 0x02, 0x08, 0x00, 0x10,\
/*  72 */ 0x10, 0x10, 0x00, 0x10, 0x00, 0x10, 0x10, 0x00,\

#endif
SQLITE_PRIVATE void sqlite3VdbeAddParseSchemaOp(Vdbe*, int, char*, u16);
SQLITE_PRIVATE void sqlite3VdbeChangeOpcode(Vdbe*, int addr, u8);
SQLITE_PRIVATE void sqlite3VdbeChangeP1(Vdbe*, int addr, int P1);
SQLITE_PRIVATE void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);
SQLITE_PRIVATE void sqlite3VdbeChangeP3(Vdbe*, int addr, int P3);
SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe*, u16 P5);
SQLITE_PRIVATE void sqlite3VdbeTypeofColumn(Vdbe*, int);
SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe*, int addr);
SQLITE_PRIVATE void sqlite3VdbeJumpHereOrPopInst(Vdbe*, int addr);
SQLITE_PRIVATE int sqlite3VdbeChangeToNoop(Vdbe*, int addr);
SQLITE_PRIVATE int sqlite3VdbeDeletePriorOpcode(Vdbe*, u8 op);
#ifdef SQLITE_DEBUG
SQLITE_PRIVATE   void sqlite3VdbeReleaseRegisters(Parse*,int addr, int n, u32 mask, int);
#else

#ifdef SQLITE_DIRECT_OVERFLOW_READ
SQLITE_PRIVATE int sqlite3PCacheIsDirty(PCache *pCache);
#endif

#endif /* _PCACHE_H_ */

/************** End of pcache.h **********************************************/



































































































































































































































































































/************** Continuing where we left off in sqliteInt.h ******************/
/************** Include mutex.h in the middle of sqliteInt.h *****************/
/************** Begin file mutex.h *******************************************/
/*
** 2007 August 28
**
** The author disclaims copyright to this source code.  In place of

   /* TH3 expects this value  ^^^^^^^^^^ to be 0x40000. Coordinate any change */
#define SQLITE_BloomFilter    0x00080000 /* Use a Bloom filter on searches */
#define SQLITE_BloomPulldown  0x00100000 /* Run Bloom filters early */
#define SQLITE_BalancedMerge  0x00200000 /* Balance multi-way merges */
#define SQLITE_ReleaseReg     0x00400000 /* Use OP_ReleaseReg for testing */
#define SQLITE_FlttnUnionAll  0x00800000 /* Disable the UNION ALL flattener */
   /* TH3 expects this value  ^^^^^^^^^^ See flatten04.test */
#define SQLITE_IndexedExpr    0x01000000 /* Pull exprs from index when able */
#define SQLITE_AllOpts        0xffffffff /* All optimizations */

/*
** Macros for testing whether or not optimizations are enabled or disabled.
*/
#define OptimizationDisabled(db, mask)  (((db)->dbOptFlags&(mask))!=0)
#define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)

** Test to see whether or not a table is a virtual table.  This is
** done as a macro so that it will be optimized out when virtual
** table support is omitted from the build.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#  define IsVirtual(X)      ((X)->eTabType==TABTYP_VTAB)
#  define ExprIsVtab(X)  \
   ((X)->op==TK_COLUMN && (X)->y.pTab->eTabType==TABTYP_VTAB)
#else
#  define IsVirtual(X)      0
#  define ExprIsVtab(X)     0
#endif

/*
** Macros to determine if a column is hidden.  IsOrdinaryHiddenColumn()

** first column to be indexed (c3) has an index of 2 in Ex1.aCol[].
** The second column to be indexed (c1) has an index of 0 in
** Ex1.aCol[], hence Ex2.aiColumn[1]==0.
**
** The Index.onError field determines whether or not the indexed columns
** must be unique and what to do if they are not.  When Index.onError=OE_None,
** it means this is not a unique index.  Otherwise it is a unique index
** and the value of Index.onError indicates which conflict resolution
** algorithm to employ when an attempt is made to insert a non-unique
** element.
**
** The colNotIdxed bitmask is used in combination with SrcItem.colUsed
** for a fast test to see if an index can serve as a covering index.
** colNotIdxed has a 1 bit for every column of the original table that
** is *not* available in the index.  Thus the expression
** "colUsed & colNotIdxed" will be non-zero if the index is not a
** covering index.  The most significant bit of of colNotIdxed will always
** be true (note-20221022-a).  If a column beyond the 63rd column of the
** table is used, the "colUsed & colNotIdxed" test will always be non-zero
** and we have to assume either that the index is not covering, or use
** an alternative (slower) algorithm to determine whether or not
** the index is covering.
**
** While parsing a CREATE TABLE or CREATE INDEX statement in order to
** generate VDBE code (as opposed to parsing one read from an sqlite_schema
** table as part of parsing an existing database schema), transient instances
** of this structure may be created. In this case the Index.tnum variable is
** used to store the address of a VDBE instruction, not a database page
** number (it cannot - the database page is not allocated until the VDBE

  unsigned isResized:1;    /* True if resizeIndexObject() has been called */
  unsigned isCovering:1;   /* True if this is a covering index */
  unsigned noSkipScan:1;   /* Do not try to use skip-scan if true */
  unsigned hasStat1:1;     /* aiRowLogEst values come from sqlite_stat1 */
  unsigned bNoQuery:1;     /* Do not use this index to optimize queries */
  unsigned bAscKeyBug:1;   /* True if the bba7b69f9849b5bf bug applies */
  unsigned bHasVCol:1;     /* Index references one or more VIRTUAL columns */
  unsigned bHasExpr:1;     /* Index contains an expression, either a literal
                           ** expression, or a reference to a VIRTUAL column */
#ifdef SQLITE_ENABLE_STAT4
  int nSample;             /* Number of elements in 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 */
  tRowcnt *aiRowEst;       /* Non-logarithmic stat1 data for this index */
  tRowcnt nRowEst0;        /* Non-logarithmic number of rows in the index */
#endif
  Bitmask colNotIdxed;     /* Unindexed columns in pTab */
};

/*
** Allowed values for Index.idxType
*/
#define SQLITE_IDXTYPE_APPDEF      0   /* Created using CREATE INDEX */
#define SQLITE_IDXTYPE_UNIQUE      1   /* Implements a UNIQUE constraint */

#define EU4_IDX    1   /* Uses IdList.a.u4.idx */
#define EU4_EXPR   2   /* Uses IdList.a.u4.pExpr -- NOT CURRENTLY USED */

/*
** The SrcItem object represents a single term in the FROM clause of a query.
** The SrcList object is mostly an array of SrcItems.
**
** The jointype starts out showing the join type between the current table
** and the next table on the list.  The parser builds the list this way.
** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
** jointype expresses the join between the table and the previous table.
**
** In the colUsed field, the high-order bit (bit 63) is set if the table
** contains more than 63 columns and the 64-th or later column is used.
**
** Union member validity:
**
**    u1.zIndexedBy          fg.isIndexedBy && !fg.isTabFunc
**    u1.pFuncArg            fg.isTabFunc   && !fg.isIndexedBy
**    u2.pIBIndex            fg.isIndexedBy && !fg.isCte
**    u2.pCteUse             fg.isCte       && !fg.isIndexedBy
*/

    unsigned isNestedFrom :1;  /* pSelect is a SF_NestedFrom subquery */
  } fg;
  int iCursor;      /* The VDBE cursor number used to access this table */
  union {
    Expr *pOn;        /* fg.isUsing==0 =>  The ON clause of a join */
    IdList *pUsing;   /* fg.isUsing==1 =>  The USING clause of a join */
  } u3;
  Bitmask colUsed;  /* Bit N set if column N used. Details above for N>62 */
  union {
    char *zIndexedBy;    /* Identifier from "INDEXED BY <zIndex>" clause */
    ExprList *pFuncArg;  /* Arguments to table-valued-function */
  } u1;
  union {
    Index *pIBIndex;  /* Index structure corresponding to u1.zIndexedBy */
    CteUse *pCteUse;  /* CTE Usage info when fg.isCte is true */
  } u2;
};

/*
** The OnOrUsing object represents either an ON clause or a USING clause.
** It can never be both at the same time, but it can be neither.
*/
struct OnOrUsing {
  Expr *pOn;         /* The ON clause of a join */
  IdList *pUsing;    /* The USING clause of a join */
};

/*
** This object represents one or more tables that are the source of
** content for an SQL statement.  For example, a single SrcList object
** is used to hold the FROM clause of a SELECT statement.  SrcList also





** represents the target tables for DELETE, INSERT, and UPDATE statements.


**







*/
struct SrcList {
  int nSrc;        /* Number of tables or subqueries in the FROM clause */
  u32 nAlloc;      /* Number of entries allocated in a[] below */
  SrcItem a[1];    /* One entry for each identifier on the list */
};

*/
struct SelectDest {
  u8 eDest;            /* How to dispose of the results.  One of SRT_* above. */
  int iSDParm;         /* A parameter used by the eDest disposal method */
  int iSDParm2;        /* A second parameter for the eDest disposal method */
  int iSdst;           /* Base register where results are written */
  int nSdst;           /* Number of registers allocated */
  char *zAffSdst;      /* Affinity used for SRT_Set, SRT_Table, and similar */
  ExprList *pOrderBy;  /* Key columns for SRT_Queue and SRT_DistQueue */
};

/*
** During code generation of statements that do inserts into AUTOINCREMENT
** tables, the following information is attached to the Table.u.autoInc.p
** pointer of each autoincrement table to record some side information that

# define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
# define DbMaskZero(M)      (M)=0
# define DbMaskSet(M,I)     (M)|=(((yDbMask)1)<<(I))
# define DbMaskAllZero(M)   (M)==0
# define DbMaskNonZero(M)   (M)!=0
#endif

/*
** For each index X that has as one of its arguments either an expression
** or the name of a virtual generated column, and if X is in scope such that
** the value of the expression can simply be read from the index, then
** there is an instance of this object on the Parse.pIdxExpr list.
**
** During code generation, while generating code to evaluate expressions,
** this list is consulted and if a matching expression is found, the value
** is read from the index rather than being recomputed.
*/
struct IndexedExpr {
  Expr *pExpr;            /* The expression contained in the index */
  int iDataCur;           /* The data cursor associated with the index */
  int iIdxCur;            /* The index cursor */
  int iIdxCol;            /* The index column that contains value of pExpr */
  u8 bMaybeNullRow;       /* True if we need an OP_IfNullRow check */
  IndexedExpr *pIENext;   /* Next in a list of all indexed expressions */
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
  const char *zIdxName;   /* Name of index, used only for bytecode comments */
#endif
};

/*
** An instance of the ParseCleanup object specifies an operation that
** should be performed after parsing to deallocation resources obtained
** during the parse and which are no longer needed.
*/
struct ParseCleanup {
  ParseCleanup *pNext;               /* Next cleanup task */

  u8 nested;           /* Number of nested calls to the parser/code generator */
  u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
  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() */
  u8 okConstFactor;    /* OK to factor out constants */
  u8 disableLookaside; /* Number of times lookaside has been disabled */
  u8 prepFlags;        /* SQLITE_PREPARE_* flags */
  u8 withinRJSubrtn;   /* Nesting level for RIGHT JOIN body subroutines */
#if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
  u8 earlyCleanup;     /* OOM inside sqlite3ParserAddCleanup() */
#endif
  int nRangeReg;       /* Size of the temporary register block */
  int iRangeReg;       /* First register in temporary register block */
  int nErr;            /* Number of errors seen */
  int nTab;            /* Number of previously allocated VDBE cursors */
  int nMem;            /* Number of memory cells used so far */
  int szOpAlloc;       /* Bytes of memory space allocated for Vdbe.aOp[] */
  int iSelfTab;        /* Table associated with an index on expr, or negative
                       ** of the base register during check-constraint eval */
  int nLabel;          /* The *negative* of the number of labels used */
  int nLabelAlloc;     /* Number of slots in aLabel */
  int *aLabel;         /* Space to hold the labels */
  ExprList *pConstExpr;/* Constant expressions */
  IndexedExpr *pIdxExpr;/* List of expressions used by active indexes */
  Token constraintName;/* Name of the constraint currently being parsed */
  yDbMask writeMask;   /* Start a write transaction on these databases */
  yDbMask cookieMask;  /* Bitmask of schema verified databases */
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */
  int regRoot;         /* Register holding root page number for new objects */
  int nMaxArg;         /* Max args passed to user function by sub-program */
  int nSelect;         /* Number of SELECT stmts. Counter for Select.selId */

    int n;                                    /* A counter */
    int iCur;                                 /* A cursor number */
    SrcList *pSrcList;                        /* FROM clause */
    struct CCurHint *pCCurHint;               /* Used by codeCursorHint() */
    struct RefSrcList *pRefSrcList;           /* sqlite3ReferencesSrcList() */
    int *aiCol;                               /* array of column indexes */
    struct IdxCover *pIdxCover;               /* Check for index coverage */

    ExprList *pGroupBy;                       /* GROUP BY clause */
    Select *pSelect;                          /* HAVING to WHERE clause ctx */
    struct WindowRewrite *pRewrite;           /* Window rewrite context */
    struct WhereConst *pConst;                /* WHERE clause constants */
    struct RenameCtx *pRename;                /* RENAME COLUMN context */
    struct Table *pTab;                       /* Table of generated column */
    struct CoveringIndexCheck *pCovIdxCk;     /* Check for covering index */
    SrcItem *pSrcItem;                        /* A single FROM clause item */
    DbFixer *pFix;                            /* See sqlite3FixSelect() */
  } u;
};

/*
** The following structure contains information used by the sqliteFix...
** routines as they walk the parse tree to make database references
** explicit.

** obtain space from malloc().
**
** The alloca() routine never returns NULL.  This will cause code paths
** that deal with sqlite3StackAlloc() failures to be unreachable.
*/
#ifdef SQLITE_USE_ALLOCA
# define sqlite3StackAllocRaw(D,N)   alloca(N)
# define sqlite3StackAllocRawNN(D,N) alloca(N)
# define sqlite3StackAllocZero(D,N)  memset(alloca(N), 0, N)
# define sqlite3StackFree(D,P)
# define sqlite3StackFreeNN(D,P)
#else
# define sqlite3StackAllocRaw(D,N)   sqlite3DbMallocRaw(D,N)
# define sqlite3StackAllocRawNN(D,N) sqlite3DbMallocRawNN(D,N)
# define sqlite3StackAllocZero(D,N)  sqlite3DbMallocZero(D,N)
# define sqlite3StackFree(D,P)       sqlite3DbFree(D,P)
# define sqlite3StackFreeNN(D,P)     sqlite3DbFreeNN(D,P)
#endif

/* Do not allow both MEMSYS5 and MEMSYS3 to be defined together.  If they
** are, disable MEMSYS3
*/
#ifdef SQLITE_ENABLE_MEMSYS5
SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);

  (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
  sqlite3PutVarint((A),(B)))
#define getVarint    sqlite3GetVarint
#define putVarint    sqlite3PutVarint


SQLITE_PRIVATE const char *sqlite3IndexAffinityStr(sqlite3*, Index*);
SQLITE_PRIVATE char *sqlite3TableAffinityStr(sqlite3*,const Table*);
SQLITE_PRIVATE void sqlite3TableAffinity(Vdbe*, Table*, int);
SQLITE_PRIVATE char sqlite3CompareAffinity(const Expr *pExpr, char aff2);
SQLITE_PRIVATE int sqlite3IndexAffinityOk(const Expr *pExpr, char idx_affinity);
SQLITE_PRIVATE char sqlite3TableColumnAffinity(const Table*,int);
SQLITE_PRIVATE char sqlite3ExprAffinity(const Expr *pExpr);
SQLITE_PRIVATE int sqlite3Atoi64(const char*, i64*, int, u8);
SQLITE_PRIVATE int sqlite3DecOrHexToI64(const char*, i64*);

SQLITE_PRIVATE int sqlite3ValueFromExpr(sqlite3 *, const Expr *, u8, u8, sqlite3_value **);
SQLITE_PRIVATE void sqlite3ValueApplyAffinity(sqlite3_value *, u8, u8);
#ifndef SQLITE_AMALGAMATION
SQLITE_PRIVATE const unsigned char sqlite3OpcodeProperty[];
SQLITE_PRIVATE const char sqlite3StrBINARY[];
SQLITE_PRIVATE const unsigned char sqlite3StdTypeLen[];
SQLITE_PRIVATE const char sqlite3StdTypeAffinity[];

SQLITE_PRIVATE const char *sqlite3StdType[];
SQLITE_PRIVATE const unsigned char sqlite3UpperToLower[];
SQLITE_PRIVATE const unsigned char *sqlite3aLTb;
SQLITE_PRIVATE const unsigned char *sqlite3aEQb;
SQLITE_PRIVATE const unsigned char *sqlite3aGTb;
SQLITE_PRIVATE const unsigned char sqlite3CtypeMap[];
SQLITE_PRIVATE SQLITE_WSD struct Sqlite3Config sqlite3Config;

SQLITE_PRIVATE Expr *sqlite3VectorFieldSubexpr(Expr*, int);
SQLITE_PRIVATE Expr *sqlite3ExprForVectorField(Parse*,Expr*,int,int);
SQLITE_PRIVATE void sqlite3VectorErrorMsg(Parse*, Expr*);

#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
SQLITE_PRIVATE const char **sqlite3CompileOptions(int *pnOpt);
#endif

#if SQLITE_OS_UNIX && defined(SQLITE_OS_KV_OPTIONAL)
SQLITE_PRIVATE int sqlite3KvvfsInit(void);
#endif

#endif /* SQLITEINT_H */

/************** End of sqliteInt.h *******************************************/
/************** Begin file os_common.h ***************************************/
/*
** 2004 May 22

#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS /* IMP: R-16824-07538 */

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build
*/
#if defined(_HAVE_SQLITE_CONFIG_H) && !defined(SQLITECONFIG_H)
/* #include "sqlite_cfg.h" */
#define SQLITECONFIG_H 1
#endif

/* These macros are provided to "stringify" the value of the define
** for those options in which the value is meaningful. */
#define CTIMEOPT_VAL_(opt) #opt
#define CTIMEOPT_VAL(opt) CTIMEOPT_VAL_(opt)

#endif
#ifdef SQLITE_DISABLE_PAGECACHE_OVERFLOW_STATS
  "DISABLE_PAGECACHE_OVERFLOW_STATS",
#endif
#ifdef SQLITE_DISABLE_SKIPAHEAD_DISTINCT
  "DISABLE_SKIPAHEAD_DISTINCT",
#endif
#ifdef SQLITE_DQS
  "DQS=" CTIMEOPT_VAL(SQLITE_DQS),
#endif
#ifdef SQLITE_ENABLE_8_3_NAMES
  "ENABLE_8_3_NAMES=" CTIMEOPT_VAL(SQLITE_ENABLE_8_3_NAMES),
#endif
#ifdef SQLITE_ENABLE_API_ARMOR
  "ENABLE_API_ARMOR",
#endif
#ifdef SQLITE_ENABLE_ATOMIC_WRITE

**    sqlite3StdType[]            The actual names of the datatypes.
**
**    sqlite3StdTypeLen[]         The length (in bytes) of each entry
**                                in sqlite3StdType[].
**
**    sqlite3StdTypeAffinity[]    The affinity associated with each entry
**                                in sqlite3StdType[].




*/
SQLITE_PRIVATE const unsigned char sqlite3StdTypeLen[] = { 3, 4, 3, 7, 4, 4 };
SQLITE_PRIVATE const char sqlite3StdTypeAffinity[] = {
  SQLITE_AFF_NUMERIC,
  SQLITE_AFF_BLOB,
  SQLITE_AFF_INTEGER,
  SQLITE_AFF_INTEGER,
  SQLITE_AFF_REAL,
  SQLITE_AFF_TEXT
};








SQLITE_PRIVATE const char *sqlite3StdType[] = {
  "ANY",
  "BLOB",
  "INT",
  "INTEGER",
  "REAL",
  "TEXT"

}
SQLITE_PRIVATE int sqlite3OsFileSize(sqlite3_file *id, i64 *pSize){
  DO_OS_MALLOC_TEST(id);
  return id->pMethods->xFileSize(id, pSize);
}
SQLITE_PRIVATE int sqlite3OsLock(sqlite3_file *id, int lockType){
  DO_OS_MALLOC_TEST(id);
  assert( lockType>=SQLITE_LOCK_SHARED && lockType<=SQLITE_LOCK_EXCLUSIVE );
  return id->pMethods->xLock(id, lockType);
}
SQLITE_PRIVATE int sqlite3OsUnlock(sqlite3_file *id, int lockType){
  assert( lockType==SQLITE_LOCK_NONE || lockType==SQLITE_LOCK_SHARED );
  return id->pMethods->xUnlock(id, lockType);
}
SQLITE_PRIVATE int sqlite3OsCheckReservedLock(sqlite3_file *id, int *pResOut){
  DO_OS_MALLOC_TEST(id);
  return id->pMethods->xCheckReservedLock(id, pResOut);
}

    /*  11 */ "InitCoroutine"    OpHelp(""),
    /*  12 */ "Yield"            OpHelp(""),
    /*  13 */ "MustBeInt"        OpHelp(""),
    /*  14 */ "Jump"             OpHelp(""),
    /*  15 */ "Once"             OpHelp(""),
    /*  16 */ "If"               OpHelp(""),
    /*  17 */ "IfNot"            OpHelp(""),
    /*  18 */ "IsType"           OpHelp("if typeof(P1.P3) in P5 goto P2"),
    /*  19 */ "Not"              OpHelp("r[P2]= !r[P1]"),
    /*  20 */ "IfNullRow"        OpHelp("if P1.nullRow then r[P3]=NULL, goto P2"),
    /*  21 */ "SeekLT"           OpHelp("key=r[P3@P4]"),
    /*  22 */ "SeekLE"           OpHelp("key=r[P3@P4]"),
    /*  23 */ "SeekGE"           OpHelp("key=r[P3@P4]"),
    /*  24 */ "SeekGT"           OpHelp("key=r[P3@P4]"),
    /*  25 */ "IfNotOpen"        OpHelp("if( !csr[P1] ) goto P2"),

    /* 186 */ "Abortable"        OpHelp(""),
  };
  return azName[i];
}
#endif

/************** End of opcodes.c *********************************************/
/************** Begin file os_kv.c *******************************************/
/*
** 2022-09-06
**
** 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 an experimental VFS layer that operates on a
** Key/Value storage engine where both keys and values must be pure
** text.
*/
/* #include <sqliteInt.h> */
#if SQLITE_OS_KV || (SQLITE_OS_UNIX && defined(SQLITE_OS_KV_OPTIONAL))

/*****************************************************************************
** Debugging logic
*/

/* SQLITE_KV_TRACE() is used for tracing calls to kvstorage routines. */
#if 0
#define SQLITE_KV_TRACE(X)  printf X
#else
#define SQLITE_KV_TRACE(X)
#endif

/* SQLITE_KV_LOG() is used for tracing calls to the VFS interface */
#if 0
#define SQLITE_KV_LOG(X)  printf X
#else
#define SQLITE_KV_LOG(X)
#endif


/*
** Forward declaration of objects used by this VFS implementation
*/
typedef struct KVVfsFile KVVfsFile;

/* A single open file.  There are only two files represented by this
** VFS - the database and the rollback journal.
*/
struct KVVfsFile {
  sqlite3_file base;              /* IO methods */
  const char *zClass;             /* Storage class */
  int isJournal;                  /* True if this is a journal file */
  unsigned int nJrnl;             /* Space allocated for aJrnl[] */
  char *aJrnl;                    /* Journal content */
  int szPage;                     /* Last known page size */
  sqlite3_int64 szDb;             /* Database file size.  -1 means unknown */
};

/*
** Methods for KVVfsFile
*/
static int kvvfsClose(sqlite3_file*);
static int kvvfsReadDb(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int kvvfsReadJrnl(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst);
static int kvvfsWriteDb(sqlite3_file*,const void*,int iAmt, sqlite3_int64);
static int kvvfsWriteJrnl(sqlite3_file*,const void*,int iAmt, sqlite3_int64);
static int kvvfsTruncateDb(sqlite3_file*, sqlite3_int64 size);
static int kvvfsTruncateJrnl(sqlite3_file*, sqlite3_int64 size);
static int kvvfsSyncDb(sqlite3_file*, int flags);
static int kvvfsSyncJrnl(sqlite3_file*, int flags);
static int kvvfsFileSizeDb(sqlite3_file*, sqlite3_int64 *pSize);
static int kvvfsFileSizeJrnl(sqlite3_file*, sqlite3_int64 *pSize);
static int kvvfsLock(sqlite3_file*, int);
static int kvvfsUnlock(sqlite3_file*, int);
static int kvvfsCheckReservedLock(sqlite3_file*, int *pResOut);
static int kvvfsFileControlDb(sqlite3_file*, int op, void *pArg);
static int kvvfsFileControlJrnl(sqlite3_file*, int op, void *pArg);
static int kvvfsSectorSize(sqlite3_file*);
static int kvvfsDeviceCharacteristics(sqlite3_file*);

/*
** Methods for sqlite3_vfs
*/
static int kvvfsOpen(sqlite3_vfs*, const char *, sqlite3_file*, int , int *);
static int kvvfsDelete(sqlite3_vfs*, const char *zName, int syncDir);
static int kvvfsAccess(sqlite3_vfs*, const char *zName, int flags, int *);
static int kvvfsFullPathname(sqlite3_vfs*, const char *zName, int, char *zOut);
static void *kvvfsDlOpen(sqlite3_vfs*, const char *zFilename);
static int kvvfsRandomness(sqlite3_vfs*, int nByte, char *zOut);
static int kvvfsSleep(sqlite3_vfs*, int microseconds);
static int kvvfsCurrentTime(sqlite3_vfs*, double*);
static int kvvfsCurrentTimeInt64(sqlite3_vfs*, sqlite3_int64*);

static sqlite3_vfs sqlite3OsKvvfsObject = {
  1,                              /* iVersion */
  sizeof(KVVfsFile),              /* szOsFile */
  1024,                           /* mxPathname */
  0,                              /* pNext */
  "kvvfs",                        /* zName */
  0,                              /* pAppData */
  kvvfsOpen,                      /* xOpen */
  kvvfsDelete,                    /* xDelete */
  kvvfsAccess,                    /* xAccess */
  kvvfsFullPathname,              /* xFullPathname */
  kvvfsDlOpen,                    /* xDlOpen */
  0,                              /* xDlError */
  0,                              /* xDlSym */
  0,                              /* xDlClose */
  kvvfsRandomness,                /* xRandomness */
  kvvfsSleep,                     /* xSleep */
  kvvfsCurrentTime,               /* xCurrentTime */
  0,                              /* xGetLastError */
  kvvfsCurrentTimeInt64           /* xCurrentTimeInt64 */
};

/* Methods for sqlite3_file objects referencing a database file
*/
static sqlite3_io_methods kvvfs_db_io_methods = {
  1,                              /* iVersion */
  kvvfsClose,                     /* xClose */
  kvvfsReadDb,                    /* xRead */
  kvvfsWriteDb,                   /* xWrite */
  kvvfsTruncateDb,                /* xTruncate */
  kvvfsSyncDb,                    /* xSync */
  kvvfsFileSizeDb,                /* xFileSize */
  kvvfsLock,                      /* xLock */
  kvvfsUnlock,                    /* xUnlock */
  kvvfsCheckReservedLock,         /* xCheckReservedLock */
  kvvfsFileControlDb,             /* xFileControl */
  kvvfsSectorSize,                /* xSectorSize */
  kvvfsDeviceCharacteristics,     /* xDeviceCharacteristics */
  0,                              /* xShmMap */
  0,                              /* xShmLock */
  0,                              /* xShmBarrier */
  0,                              /* xShmUnmap */
  0,                              /* xFetch */
  0                               /* xUnfetch */
};

/* Methods for sqlite3_file objects referencing a rollback journal
*/
static sqlite3_io_methods kvvfs_jrnl_io_methods = {
  1,                              /* iVersion */
  kvvfsClose,                     /* xClose */
  kvvfsReadJrnl,                  /* xRead */
  kvvfsWriteJrnl,                 /* xWrite */
  kvvfsTruncateJrnl,              /* xTruncate */
  kvvfsSyncJrnl,                  /* xSync */
  kvvfsFileSizeJrnl,              /* xFileSize */
  kvvfsLock,                      /* xLock */
  kvvfsUnlock,                    /* xUnlock */
  kvvfsCheckReservedLock,         /* xCheckReservedLock */
  kvvfsFileControlJrnl,           /* xFileControl */
  kvvfsSectorSize,                /* xSectorSize */
  kvvfsDeviceCharacteristics,     /* xDeviceCharacteristics */
  0,                              /* xShmMap */
  0,                              /* xShmLock */
  0,                              /* xShmBarrier */
  0,                              /* xShmUnmap */
  0,                              /* xFetch */
  0                               /* xUnfetch */
};

/****** Storage subsystem **************************************************/
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

/* Forward declarations for the low-level storage engine
*/
static int kvstorageWrite(const char*, const char *zKey, const char *zData);
static int kvstorageDelete(const char*, const char *zKey);
static int kvstorageRead(const char*, const char *zKey, char *zBuf, int nBuf);
#define KVSTORAGE_KEY_SZ  32

/* Expand the key name with an appropriate prefix and put the result
** zKeyOut[].  The zKeyOut[] buffer is assumed to hold at least
** KVSTORAGE_KEY_SZ bytes.
*/
static void kvstorageMakeKey(
  const char *zClass,
  const char *zKeyIn,
  char *zKeyOut
){
  sqlite3_snprintf(KVSTORAGE_KEY_SZ, zKeyOut, "kvvfs-%s-%s", zClass, zKeyIn);
}

/* Write content into a key.  zClass is the particular namespace of the
** underlying key/value store to use - either "local" or "session".
**
** Both zKey and zData are zero-terminated pure text strings.
**
** Return the number of errors.
*/
static int kvstorageWrite(
  const char *zClass,
  const char *zKey,
  const char *zData
){
  FILE *fd;
  char zXKey[KVSTORAGE_KEY_SZ];
  kvstorageMakeKey(zClass, zKey, zXKey);
  fd = fopen(zXKey, "wb");
  if( fd ){
    SQLITE_KV_TRACE(("KVVFS-WRITE  %-15s (%d) %.50s%s\n", zXKey,
                 (int)strlen(zData), zData,
                 strlen(zData)>50 ? "..." : ""));
    fputs(zData, fd);
    fclose(fd);
    return 0;
  }else{
    return 1;
  }
}

/* Delete a key (with its corresponding data) from the key/value
** namespace given by zClass.  If the key does not previously exist,
** this routine is a no-op.
*/
static int kvstorageDelete(const char *zClass, const char *zKey){
  char zXKey[KVSTORAGE_KEY_SZ];
  kvstorageMakeKey(zClass, zKey, zXKey);
  unlink(zXKey);
  SQLITE_KV_TRACE(("KVVFS-DELETE %-15s\n", zXKey));
  return 0;
}

/* Read the value associated with a zKey from the key/value namespace given
** by zClass and put the text data associated with that key in the first
** nBuf bytes of zBuf[].  The value might be truncated if zBuf is not large
** enough to hold it all.  The value put into zBuf must always be zero
** terminated, even if it gets truncated because nBuf is not large enough.
**
** Return the total number of bytes in the data, without truncation, and
** not counting the final zero terminator.   Return -1 if the key does
** not exist.
**
** If nBuf<=0 then this routine simply returns the size of the data without
** actually reading it.
*/
static int kvstorageRead(
  const char *zClass,
  const char *zKey,
  char *zBuf,
  int nBuf
){
  FILE *fd;
  struct stat buf;
  char zXKey[KVSTORAGE_KEY_SZ];
  kvstorageMakeKey(zClass, zKey, zXKey);
  if( access(zXKey, R_OK)!=0
   || stat(zXKey, &buf)!=0
   || !S_ISREG(buf.st_mode)
  ){
    SQLITE_KV_TRACE(("KVVFS-READ   %-15s (-1)\n", zXKey));
    return -1;
  }
  if( nBuf<=0 ){
    return (int)buf.st_size;
  }else if( nBuf==1 ){
    zBuf[0] = 0;
    SQLITE_KV_TRACE(("KVVFS-READ   %-15s (%d)\n", zXKey,
                 (int)buf.st_size));
    return (int)buf.st_size;
  }
  if( nBuf > buf.st_size + 1 ){
    nBuf = buf.st_size + 1;
  }
  fd = fopen(zXKey, "rb");
  if( fd==0 ){
    SQLITE_KV_TRACE(("KVVFS-READ   %-15s (-1)\n", zXKey));
    return -1;
  }else{
    sqlite3_int64 n = fread(zBuf, 1, nBuf-1, fd);
    fclose(fd);
    zBuf[n] = 0;
    SQLITE_KV_TRACE(("KVVFS-READ   %-15s (%lld) %.50s%s\n", zXKey,
                 n, zBuf, n>50 ? "..." : ""));
    return (int)n;
  }
}

/*
** An internal level of indirection which enables us to replace the
** kvvfs i/o methods with JavaScript implementations in WASM builds.
** Maintenance reminder: if this struct changes in any way, the JSON
** rendering of its structure must be updated in
** sqlite3_wasm_enum_json(). There are no binary compatibility
** concerns, so it does not need an iVersion member. This file is
** necessarily always compiled together with sqlite3_wasm_enum_json(),
** and JS code dynamically creates the mapping of members based on
** that JSON description.
*/
typedef struct sqlite3_kvvfs_methods sqlite3_kvvfs_methods;
struct sqlite3_kvvfs_methods {
  int (*xRead)(const char *zClass, const char *zKey, char *zBuf, int nBuf);
  int (*xWrite)(const char *zClass, const char *zKey, const char *zData);
  int (*xDelete)(const char *zClass, const char *zKey);
  const int nKeySize;
};

/*
** This object holds the kvvfs I/O methods which may be swapped out
** for JavaScript-side implementations in WASM builds. In such builds
** it cannot be const, but in native builds it should be so that
** the compiler can hopefully optimize this level of indirection out.
** That said, kvvfs is intended primarily for use in WASM builds.
**
** Note that this is not explicitly flagged as static because the
** amalgamation build will tag it with SQLITE_PRIVATE.
*/
#ifndef SQLITE_WASM
const
#endif
SQLITE_PRIVATE sqlite3_kvvfs_methods sqlite3KvvfsMethods = {
kvstorageRead,
kvstorageWrite,
kvstorageDelete,
KVSTORAGE_KEY_SZ
};

/****** Utility subroutines ************************************************/

/*
** Encode binary into the text encoded used to persist on disk.
** The output text is stored in aOut[], which must be at least
** nData+1 bytes in length.
**
** Return the actual length of the encoded text, not counting the
** zero terminator at the end.
**
** Encoding format
** ---------------
**
**   *  Non-zero bytes are encoded as upper-case hexadecimal
**
**   *  A sequence of one or more zero-bytes that are not at the
**      beginning of the buffer are encoded as a little-endian
**      base-26 number using a..z.  "a" means 0.  "b" means 1,
**      "z" means 25.  "ab" means 26.  "ac" means 52.  And so forth.
**
**   *  Because there is no overlap between the encoding characters
**      of hexadecimal and base-26 numbers, it is always clear where
**      one stops and the next begins.
*/
static int kvvfsEncode(const char *aData, int nData, char *aOut){
  int i, j;
  const unsigned char *a = (const unsigned char*)aData;
  for(i=j=0; i<nData; i++){
    unsigned char c = a[i];
    if( c!=0 ){
      aOut[j++] = "0123456789ABCDEF"[c>>4];
      aOut[j++] = "0123456789ABCDEF"[c&0xf];
    }else{
      /* A sequence of 1 or more zeros is stored as a little-endian
      ** base-26 number using a..z as the digits. So one zero is "b".
      ** Two zeros is "c". 25 zeros is "z", 26 zeros is "ab", 27 is "bb",
      ** and so forth.
      */
      int k;
      for(k=1; i+k<nData && a[i+k]==0; k++){}
      i += k-1;
      while( k>0 ){
        aOut[j++] = 'a'+(k%26);
        k /= 26;
      }
    }
  }
  aOut[j] = 0;
  return j;
}

static const signed char kvvfsHexValue[256] = {
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
   0,  1,  2,  3,  4,  5,  6,  7,    8,  9, -1, -1, -1, -1, -1, -1,
  -1, 10, 11, 12, 13, 14, 15, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,

  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,   -1, -1, -1, -1, -1, -1, -1, -1
};

/*
** Decode the text encoding back to binary.  The binary content is
** written into pOut, which must be at least nOut bytes in length.
**
** The return value is the number of bytes actually written into aOut[].
*/
static int kvvfsDecode(const char *a, char *aOut, int nOut){
  int i, j;
  int c;
  const unsigned char *aIn = (const unsigned char*)a;
  i = 0;
  j = 0;
  while( 1 ){
    c = kvvfsHexValue[aIn[i]];
    if( c<0 ){
      int n = 0;
      int mult = 1;
      c = aIn[i];
      if( c==0 ) break;
      while( c>='a' && c<='z' ){
        n += (c - 'a')*mult;
        mult *= 26;
        c = aIn[++i];
      }
      if( j+n>nOut ) return -1;
      memset(&aOut[j], 0, n);
      j += n;
      c = aIn[i];
      if( c==0 ) break;
    }else{
      aOut[j] = c<<4;
      c = kvvfsHexValue[aIn[++i]];
      if( c<0 ) break;
      aOut[j++] += c;
      i++;
    }
  }
  return j;
}

/*
** Decode a complete journal file.  Allocate space in pFile->aJrnl
** and store the decoding there.  Or leave pFile->aJrnl set to NULL
** if an error is encountered.
**
** The first few characters of the text encoding will be a little-endian
** base-26 number (digits a..z) that is the total number of bytes
** in the decoded journal file image.  This base-26 number is followed
** by a single space, then the encoding of the journal.  The space
** separator is required to act as a terminator for the base-26 number.
*/
static void kvvfsDecodeJournal(
  KVVfsFile *pFile,      /* Store decoding in pFile->aJrnl */
  const char *zTxt,      /* Text encoding.  Zero-terminated */
  int nTxt               /* Bytes in zTxt, excluding zero terminator */
){
  unsigned int n = 0;
  int c, i, mult;
  i = 0;
  mult = 1;
  while( (c = zTxt[i++])>='a' && c<='z' ){
    n += (zTxt[i] - 'a')*mult;
    mult *= 26;
  }
  sqlite3_free(pFile->aJrnl);
  pFile->aJrnl = sqlite3_malloc64( n );
  if( pFile->aJrnl==0 ){
    pFile->nJrnl = 0;
    return;
  }
  pFile->nJrnl = n;
  n = kvvfsDecode(zTxt+i, pFile->aJrnl, pFile->nJrnl);
  if( n<pFile->nJrnl ){
    sqlite3_free(pFile->aJrnl);
    pFile->aJrnl = 0;
    pFile->nJrnl = 0;
  }
}

/*
** Read or write the "sz" element, containing the database file size.
*/
static sqlite3_int64 kvvfsReadFileSize(KVVfsFile *pFile){
  char zData[50];
  zData[0] = 0;
  sqlite3KvvfsMethods.xRead(pFile->zClass, "sz", zData, sizeof(zData)-1);
  return strtoll(zData, 0, 0);
}
static int kvvfsWriteFileSize(KVVfsFile *pFile, sqlite3_int64 sz){
  char zData[50];
  sqlite3_snprintf(sizeof(zData), zData, "%lld", sz);
  return sqlite3KvvfsMethods.xWrite(pFile->zClass, "sz", zData);
}

/****** sqlite3_io_methods methods ******************************************/

/*
** Close an kvvfs-file.
*/
static int kvvfsClose(sqlite3_file *pProtoFile){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;

  SQLITE_KV_LOG(("xClose %s %s\n", pFile->zClass,
             pFile->isJournal ? "journal" : "db"));
  sqlite3_free(pFile->aJrnl);
  return SQLITE_OK;
}

/*
** Read from the -journal file.
*/
static int kvvfsReadJrnl(
  sqlite3_file *pProtoFile,
  void *zBuf,
  int iAmt,
  sqlite_int64 iOfst
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  assert( pFile->isJournal );
  SQLITE_KV_LOG(("xRead('%s-journal',%d,%lld)\n", pFile->zClass, iAmt, iOfst));
  if( pFile->aJrnl==0 ){
    int szTxt = kvstorageRead(pFile->zClass, "jrnl", 0, 0);
    char *aTxt;
    if( szTxt<=4 ){
      return SQLITE_IOERR;
    }
    aTxt = sqlite3_malloc64( szTxt+1 );
    if( aTxt==0 ) return SQLITE_NOMEM;
    kvstorageRead(pFile->zClass, "jrnl", aTxt, szTxt+1);
    kvvfsDecodeJournal(pFile, aTxt, szTxt);
    sqlite3_free(aTxt);
    if( pFile->aJrnl==0 ) return SQLITE_IOERR;
  }
  if( iOfst+iAmt>pFile->nJrnl ){
    return SQLITE_IOERR_SHORT_READ;
  }
  memcpy(zBuf, pFile->aJrnl+iOfst, iAmt);
  return SQLITE_OK;
}

/*
** Read from the database file.
*/
static int kvvfsReadDb(
  sqlite3_file *pProtoFile,
  void *zBuf,
  int iAmt,
  sqlite_int64 iOfst
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  unsigned int pgno;
  int got, n;
  char zKey[30];
  char aData[133073];
  assert( iOfst>=0 );
  assert( iAmt>=0 );
  SQLITE_KV_LOG(("xRead('%s-db',%d,%lld)\n", pFile->zClass, iAmt, iOfst));
  if( iOfst+iAmt>=512 ){
    if( (iOfst % iAmt)!=0 ){
      return SQLITE_IOERR_READ;
    }
    if( (iAmt & (iAmt-1))!=0 || iAmt<512 || iAmt>65536 ){
      return SQLITE_IOERR_READ;
    }
    pFile->szPage = iAmt;
    pgno = 1 + iOfst/iAmt;
  }else{
    pgno = 1;
  }
  sqlite3_snprintf(sizeof(zKey), zKey, "%u", pgno);
  got = sqlite3KvvfsMethods.xRead(pFile->zClass, zKey, aData, sizeof(aData)-1);
  if( got<0 ){
    n = 0;
  }else{
    aData[got] = 0;
    if( iOfst+iAmt<512 ){
      int k = iOfst+iAmt;
      aData[k*2] = 0;
      n = kvvfsDecode(aData, &aData[2000], sizeof(aData)-2000);
      if( n>=iOfst+iAmt ){
        memcpy(zBuf, &aData[2000+iOfst], iAmt);
        n = iAmt;
      }else{
        n = 0;
      }
    }else{
      n = kvvfsDecode(aData, zBuf, iAmt);
    }
  }
  if( n<iAmt ){
    memset(zBuf+n, 0, iAmt-n);
    return SQLITE_IOERR_SHORT_READ;
  }
  return SQLITE_OK;
}


/*
** Write into the -journal file.
*/
static int kvvfsWriteJrnl(
  sqlite3_file *pProtoFile,
  const void *zBuf,
  int iAmt,
  sqlite_int64 iOfst
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  sqlite3_int64 iEnd = iOfst+iAmt;
  SQLITE_KV_LOG(("xWrite('%s-journal',%d,%lld)\n", pFile->zClass, iAmt, iOfst));
  if( iEnd>=0x10000000 ) return SQLITE_FULL;
  if( pFile->aJrnl==0 || pFile->nJrnl<iEnd ){
    char *aNew = sqlite3_realloc(pFile->aJrnl, iEnd);
    if( aNew==0 ){
      return SQLITE_IOERR_NOMEM;
    }
    pFile->aJrnl = aNew;
    if( pFile->nJrnl<iOfst ){
      memset(pFile->aJrnl+pFile->nJrnl, 0, iOfst-pFile->nJrnl);
    }
    pFile->nJrnl = iEnd;
  }
  memcpy(pFile->aJrnl+iOfst, zBuf, iAmt);
  return SQLITE_OK;
}

/*
** Write into the database file.
*/
static int kvvfsWriteDb(
  sqlite3_file *pProtoFile,
  const void *zBuf,
  int iAmt,
  sqlite_int64 iOfst
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  unsigned int pgno;
  char zKey[30];
  char aData[131073];
  SQLITE_KV_LOG(("xWrite('%s-db',%d,%lld)\n", pFile->zClass, iAmt, iOfst));
  assert( iAmt>=512 && iAmt<=65536 );
  assert( (iAmt & (iAmt-1))==0 );
  assert( pFile->szPage<0 || pFile->szPage==iAmt );
  pFile->szPage = iAmt;
  pgno = 1 + iOfst/iAmt;
  sqlite3_snprintf(sizeof(zKey), zKey, "%u", pgno);
  kvvfsEncode(zBuf, iAmt, aData);
  if( sqlite3KvvfsMethods.xWrite(pFile->zClass, zKey, aData) ){
    return SQLITE_IOERR;
  }
  if( iOfst+iAmt > pFile->szDb ){
    pFile->szDb = iOfst + iAmt;
  }
  return SQLITE_OK;
}

/*
** Truncate an kvvfs-file.
*/
static int kvvfsTruncateJrnl(sqlite3_file *pProtoFile, sqlite_int64 size){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  SQLITE_KV_LOG(("xTruncate('%s-journal',%lld)\n", pFile->zClass, size));
  assert( size==0 );
  sqlite3KvvfsMethods.xDelete(pFile->zClass, "jrnl");
  sqlite3_free(pFile->aJrnl);
  pFile->aJrnl = 0;
  pFile->nJrnl = 0;
  return SQLITE_OK;
}
static int kvvfsTruncateDb(sqlite3_file *pProtoFile, sqlite_int64 size){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  if( pFile->szDb>size
   && pFile->szPage>0
   && (size % pFile->szPage)==0
  ){
    char zKey[50];
    unsigned int pgno, pgnoMax;
    SQLITE_KV_LOG(("xTruncate('%s-db',%lld)\n", pFile->zClass, size));
    pgno = 1 + size/pFile->szPage;
    pgnoMax = 2 + pFile->szDb/pFile->szPage;
    while( pgno<=pgnoMax ){
      sqlite3_snprintf(sizeof(zKey), zKey, "%u", pgno);
      sqlite3KvvfsMethods.xDelete(pFile->zClass, zKey);
      pgno++;
    }
    pFile->szDb = size;
    return kvvfsWriteFileSize(pFile, size) ? SQLITE_IOERR : SQLITE_OK;
  }
  return SQLITE_IOERR;
}

/*
** Sync an kvvfs-file.
*/
static int kvvfsSyncJrnl(sqlite3_file *pProtoFile, int flags){
  int i, n;
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  char *zOut;
  SQLITE_KV_LOG(("xSync('%s-journal')\n", pFile->zClass));
  if( pFile->nJrnl<=0 ){
    return kvvfsTruncateJrnl(pProtoFile, 0);
  }
  zOut = sqlite3_malloc64( pFile->nJrnl*2 + 50 );
  if( zOut==0 ){
    return SQLITE_IOERR_NOMEM;
  }
  n = pFile->nJrnl;
  i = 0;
  do{
    zOut[i++] = 'a' + (n%26);
    n /= 26;
  }while( n>0 );
  zOut[i++] = ' ';
  kvvfsEncode(pFile->aJrnl, pFile->nJrnl, &zOut[i]);
  i = sqlite3KvvfsMethods.xWrite(pFile->zClass, "jrnl", zOut);
  sqlite3_free(zOut);
  return i ? SQLITE_IOERR : SQLITE_OK;
}
static int kvvfsSyncDb(sqlite3_file *pProtoFile, int flags){
  return SQLITE_OK;
}

/*
** Return the current file-size of an kvvfs-file.
*/
static int kvvfsFileSizeJrnl(sqlite3_file *pProtoFile, sqlite_int64 *pSize){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  SQLITE_KV_LOG(("xFileSize('%s-journal')\n", pFile->zClass));
  *pSize = pFile->nJrnl;
  return SQLITE_OK;
}
static int kvvfsFileSizeDb(sqlite3_file *pProtoFile, sqlite_int64 *pSize){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  SQLITE_KV_LOG(("xFileSize('%s-db')\n", pFile->zClass));
  if( pFile->szDb>=0 ){
    *pSize = pFile->szDb;
  }else{
    *pSize = kvvfsReadFileSize(pFile);
  }
  return SQLITE_OK;
}

/*
** Lock an kvvfs-file.
*/
static int kvvfsLock(sqlite3_file *pProtoFile, int eLock){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  assert( !pFile->isJournal );
  SQLITE_KV_LOG(("xLock(%s,%d)\n", pFile->zClass, eLock));

  if( eLock!=SQLITE_LOCK_NONE ){
    pFile->szDb = kvvfsReadFileSize(pFile);
  }
  return SQLITE_OK;
}

/*
** Unlock an kvvfs-file.
*/
static int kvvfsUnlock(sqlite3_file *pProtoFile, int eLock){
  KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
  assert( !pFile->isJournal );
  SQLITE_KV_LOG(("xUnlock(%s,%d)\n", pFile->zClass, eLock));
  if( eLock==SQLITE_LOCK_NONE ){
    pFile->szDb = -1;
  }
  return SQLITE_OK;
}

/*
** Check if another file-handle holds a RESERVED lock on an kvvfs-file.
*/
static int kvvfsCheckReservedLock(sqlite3_file *pProtoFile, int *pResOut){
  SQLITE_KV_LOG(("xCheckReservedLock\n"));
  *pResOut = 0;
  return SQLITE_OK;
}

/*
** File control method. For custom operations on an kvvfs-file.
*/
static int kvvfsFileControlJrnl(sqlite3_file *pProtoFile, int op, void *pArg){
  SQLITE_KV_LOG(("xFileControl(%d) on journal\n", op));
  return SQLITE_NOTFOUND;
}
static int kvvfsFileControlDb(sqlite3_file *pProtoFile, int op, void *pArg){
  SQLITE_KV_LOG(("xFileControl(%d) on database\n", op));
  if( op==SQLITE_FCNTL_SYNC ){
    KVVfsFile *pFile = (KVVfsFile *)pProtoFile;
    int rc = SQLITE_OK;
    SQLITE_KV_LOG(("xSync('%s-db')\n", pFile->zClass));
    if( pFile->szDb>0 && 0!=kvvfsWriteFileSize(pFile, pFile->szDb) ){
      rc = SQLITE_IOERR;
    }
    return rc;
  }
  return SQLITE_NOTFOUND;
}

/*
** Return the sector-size in bytes for an kvvfs-file.
*/
static int kvvfsSectorSize(sqlite3_file *pFile){
  return 512;
}

/*
** Return the device characteristic flags supported by an kvvfs-file.
*/
static int kvvfsDeviceCharacteristics(sqlite3_file *pProtoFile){
  return 0;
}

/****** sqlite3_vfs methods *************************************************/

/*
** Open an kvvfs file handle.
*/
static int kvvfsOpen(
  sqlite3_vfs *pProtoVfs,
  const char *zName,
  sqlite3_file *pProtoFile,
  int flags,
  int *pOutFlags
){
  KVVfsFile *pFile = (KVVfsFile*)pProtoFile;
  if( zName==0 ) zName = "";
  SQLITE_KV_LOG(("xOpen(\"%s\")\n", zName));
  if( strcmp(zName, "local")==0
   || strcmp(zName, "session")==0
  ){
    pFile->isJournal = 0;
    pFile->base.pMethods = &kvvfs_db_io_methods;
  }else
  if( strcmp(zName, "local-journal")==0
   || strcmp(zName, "session-journal")==0
  ){
    pFile->isJournal = 1;
    pFile->base.pMethods = &kvvfs_jrnl_io_methods;
  }else{
    return SQLITE_CANTOPEN;
  }
  if( zName[0]=='s' ){
    pFile->zClass = "session";
  }else{
    pFile->zClass = "local";
  }
  pFile->aJrnl = 0;
  pFile->nJrnl = 0;
  pFile->szPage = -1;
  pFile->szDb = -1;
  return SQLITE_OK;
}

/*
** Delete the file located at zPath. If the dirSync argument is true,
** ensure the file-system modifications are synced to disk before
** returning.
*/
static int kvvfsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  if( strcmp(zPath, "local-journal")==0 ){
    sqlite3KvvfsMethods.xDelete("local", "jrnl");
  }else
  if( strcmp(zPath, "session-journal")==0 ){
    sqlite3KvvfsMethods.xDelete("session", "jrnl");
  }
  return SQLITE_OK;
}

/*
** Test for access permissions. Return true if the requested permission
** is available, or false otherwise.
*/
static int kvvfsAccess(
  sqlite3_vfs *pProtoVfs,
  const char *zPath,
  int flags,
  int *pResOut
){
  SQLITE_KV_LOG(("xAccess(\"%s\")\n", zPath));
  if( strcmp(zPath, "local-journal")==0 ){
    *pResOut = sqlite3KvvfsMethods.xRead("local", "jrnl", 0, 0)>0;
  }else
  if( strcmp(zPath, "session-journal")==0 ){
    *pResOut = sqlite3KvvfsMethods.xRead("session", "jrnl", 0, 0)>0;
  }else
  if( strcmp(zPath, "local")==0 ){
    *pResOut = sqlite3KvvfsMethods.xRead("local", "sz", 0, 0)>0;
  }else
  if( strcmp(zPath, "session")==0 ){
    *pResOut = sqlite3KvvfsMethods.xRead("session", "sz", 0, 0)>0;
  }else
  {
    *pResOut = 0;
  }
  SQLITE_KV_LOG(("xAccess returns %d\n",*pResOut));
  return SQLITE_OK;
}

/*
** Populate buffer zOut with the full canonical pathname corresponding
** to the pathname in zPath. zOut is guaranteed to point to a buffer
** of at least (INST_MAX_PATHNAME+1) bytes.
*/
static int kvvfsFullPathname(
  sqlite3_vfs *pVfs,
  const char *zPath,
  int nOut,
  char *zOut
){
  size_t nPath;
#ifdef SQLITE_OS_KV_ALWAYS_LOCAL
  zPath = "local";
#endif
  nPath = strlen(zPath);
  SQLITE_KV_LOG(("xFullPathname(\"%s\")\n", zPath));
  if( nOut<nPath+1 ) nPath = nOut - 1;
  memcpy(zOut, zPath, nPath);
  zOut[nPath] = 0;
  return SQLITE_OK;
}

/*
** Open the dynamic library located at zPath and return a handle.
*/
static void *kvvfsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
  return 0;
}

/*
** Populate the buffer pointed to by zBufOut with nByte bytes of
** random data.
*/
static int kvvfsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
  memset(zBufOut, 0, nByte);
  return nByte;
}

/*
** Sleep for nMicro microseconds. Return the number of microseconds
** actually slept.
*/
static int kvvfsSleep(sqlite3_vfs *pVfs, int nMicro){
  return SQLITE_OK;
}

/*
** Return the current time as a Julian Day number in *pTimeOut.
*/
static int kvvfsCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
  sqlite3_int64 i = 0;
  int rc;
  rc = kvvfsCurrentTimeInt64(0, &i);
  *pTimeOut = i/86400000.0;
  return rc;
}
#include <sys/time.h>
static int kvvfsCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *pTimeOut){
  static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
  struct timeval sNow;
  (void)gettimeofday(&sNow, 0);  /* Cannot fail given valid arguments */
  *pTimeOut = unixEpoch + 1000*(sqlite3_int64)sNow.tv_sec + sNow.tv_usec/1000;
  return SQLITE_OK;
}
#endif /* SQLITE_OS_KV || SQLITE_OS_UNIX */

#if SQLITE_OS_KV
/*
** This routine is called initialize the KV-vfs as the default VFS.
*/
SQLITE_API int sqlite3_os_init(void){
  return sqlite3_vfs_register(&sqlite3OsKvvfsObject, 1);
}
SQLITE_API int sqlite3_os_end(void){
  return SQLITE_OK;
}
#endif /* SQLITE_OS_KV */

#if SQLITE_OS_UNIX && defined(SQLITE_OS_KV_OPTIONAL)
SQLITE_PRIVATE int sqlite3KvvfsInit(void){
  return sqlite3_vfs_register(&sqlite3OsKvvfsObject, 0);
}
#endif

/************** End of os_kv.c ***********************************************/
/************** Begin file os_unix.c *****************************************/
/*
** 2004 May 22
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**

# undef USE_PREAD64
# define USE_PREAD 1
#endif

/*
** standard include files.
*/
#include <sys/types.h>   /* amalgamator: keep */
#include <sys/stat.h>    /* amalgamator: keep */
#include <fcntl.h>
#include <sys/ioctl.h>
#include <unistd.h>      /* amalgamator: keep */
/* #include <time.h> */
#include <sys/time.h>    /* amalgamator: keep */
#include <errno.h>
#if !defined(SQLITE_OMIT_WAL) || SQLITE_MAX_MMAP_SIZE>0
# include <sys/mman.h>
#endif

#if SQLITE_ENABLE_LOCKING_STYLE
/* # include <sys/ioctl.h> */

#ifdef SQLITE_DEFAULT_UNIX_VFS
    sqlite3_vfs_register(&aVfs[i],
           0==strcmp(aVfs[i].zName,SQLITE_DEFAULT_UNIX_VFS));
#else
    sqlite3_vfs_register(&aVfs[i], i==0);
#endif
  }
#ifdef SQLITE_OS_KV_OPTIONAL
  sqlite3KvvfsInit();
#endif
  unixBigLock = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1);

#ifndef SQLITE_OMIT_WAL
  /* Validate lock assumptions */
  assert( SQLITE_SHM_NLOCK==8 );  /* Number of available locks */
  assert( UNIX_SHM_BASE==120  );  /* Start of locking area */
  /* Locks:

      }
    }
  }
  return 0;
}

/*
** If sqlite3_temp_directory is defined, take the mutex and return true.
**
** If sqlite3_temp_directory is NULL (undefined), omit the mutex and
** return false.
*/
static int winTempDirDefined(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  if( sqlite3_temp_directory!=0 ) return 1;
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_TEMPDIR));
  return 0;
}

        ** number of bytes in fragments may not exceed 60. */
        if( aData[hdr+7]>57 ) return 0;

        /* Remove the slot from the free-list. Update the number of
        ** fragmented bytes within the page. */
        memcpy(&aData[iAddr], &aData[pc], 2);
        aData[hdr+7] += (u8)x;

        return &aData[pc];
      }else if( x+pc > maxPC ){
        /* This slot extends off the end of the usable part of the page */
        *pRc = SQLITE_CORRUPT_PAGE(pPg);
        return 0;
      }else{
        /* The slot remains on the free-list. Reduce its size to account

          }
          if( iFrom==get4byte(pCell+info.nSize-4) ){
            put4byte(pCell+info.nSize-4, iTo);
            break;
          }
        }
      }else{
        if( pCell+4 > pPage->aData+pPage->pBt->usableSize ){
          return SQLITE_CORRUPT_PAGE(pPage);
        }
        if( get4byte(pCell)==iFrom ){
          put4byte(pCell, iTo);
          break;
        }
      }
    }

      pCur->eState = CURSOR_VALID;
      if( pCur->skipNext>0 ) return SQLITE_OK;
    }
  }

  pPage = pCur->pPage;
  idx = ++pCur->ix;
  if( NEVER(!pPage->isInit) || sqlite3FaultSim(412) ){







    return SQLITE_CORRUPT_BKPT;
  }

  if( idx>=pPage->nCell ){
    if( !pPage->leaf ){
      rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
      if( rc ) return rc;

  MemPage *pPrevTrunk = 0;
  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);
  /* EVIDENCE-OF: R-21003-45125 The 4-byte big-endian integer at offset 36
  ** stores the total number of pages on the freelist. */
  n = get4byte(&pPage1->aData[36]);
  testcase( n==mxPage-1 );
  if( n>=mxPage ){
    return SQLITE_CORRUPT_BKPT;
  }
  if( n>0 ){
    /* There are pages on the freelist.  Reuse one of those pages. */

          pCur->apPage[0] = pPage;
          pCur->pPage = pCur->apPage[1];
          assert( pCur->pPage->nOverflow );
        }
      }else{
        break;
      }
    }else if( sqlite3PagerPageRefcount(pPage->pDbPage)>1 ){
      /* The page being written is not a root page, and there is currently
      ** more than one reference to it. This only happens if the page is one
      ** of its own ancestor pages. Corruption. */
      rc = SQLITE_CORRUPT_BKPT;
    }else{
      MemPage * const pParent = pCur->apPage[iPage-1];
      int const iIdx = pCur->aiIdx[iPage-1];

      rc = sqlite3PagerWrite(pParent->pDbPage);
      if( rc==SQLITE_OK && pParent->nFree<0 ){
        rc = btreeComputeFreeSpace(pParent);

    default: {
      assert( aff==SQLITE_AFF_TEXT );
      assert( MEM_Str==(MEM_Blob>>3) );
      pMem->flags |= (pMem->flags&MEM_Blob)>>3;
      sqlite3ValueApplyAffinity(pMem, SQLITE_AFF_TEXT, encoding);
      assert( pMem->flags & MEM_Str || pMem->db->mallocFailed );
      pMem->flags &= ~(MEM_Int|MEM_Real|MEM_IntReal|MEM_Blob|MEM_Zero);
      if( encoding!=SQLITE_UTF8 ) pMem->n &= ~1;
      return sqlite3VdbeChangeEncoding(pMem, encoding);
    }
  }
  return SQLITE_OK;
}

/*

  return valueToText(pVal, enc)!=0 ? pVal->n : 0;
}
SQLITE_PRIVATE int sqlite3ValueBytes(sqlite3_value *pVal, u8 enc){
  Mem *p = (Mem*)pVal;
  assert( (p->flags & MEM_Null)==0 || (p->flags & (MEM_Str|MEM_Blob))==0 );
  if( (p->flags & MEM_Str)!=0 && pVal->enc==enc ){
    return p->n;
  }
  if( (p->flags & MEM_Str)!=0 && enc!=SQLITE_UTF8 && pVal->enc!=SQLITE_UTF8 ){
    return p->n;
  }
  if( (p->flags & MEM_Blob)!=0 ){
    if( p->flags & MEM_Zero ){
      return p->n + p->u.nZero;
    }else{
      return p->n;
    }

  assert( addr>=0 );
  sqlite3VdbeGetOp(p,addr)->p3 = val;
}
SQLITE_PRIVATE void sqlite3VdbeChangeP5(Vdbe *p, u16 p5){
  assert( p->nOp>0 || p->db->mallocFailed );
  if( p->nOp>0 ) p->aOp[p->nOp-1].p5 = p5;
}

/*
** If the previous opcode is an OP_Column that delivers results
** into register iDest, then add the OPFLAG_TYPEOFARG flag to that
** opcode.
*/
SQLITE_PRIVATE void sqlite3VdbeTypeofColumn(Vdbe *p, int iDest){
  VdbeOp *pOp = sqlite3VdbeGetLastOp(p);
  if( pOp->p3==iDest && pOp->opcode==OP_Column ){
    pOp->p5 |= OPFLAG_TYPEOFARG;
  }
}

/*
** Change the P2 operand of instruction addr so that it points to
** the address of the next instruction to be coded.
*/
SQLITE_PRIVATE void sqlite3VdbeJumpHere(Vdbe *p, int addr){
  sqlite3VdbeChangeP2(p, addr, p->nOp);

  VVA_ONLY( mem1.szMalloc = 0; ) /* Only needed by assert() statements */
  assert( pPKey2->pKeyInfo->nAllField>=pPKey2->nField
       || CORRUPT_DB );
  assert( pPKey2->pKeyInfo->aSortFlags!=0 );
  assert( pPKey2->pKeyInfo->nKeyField>0 );
  assert( idx1<=szHdr1 || CORRUPT_DB );

  while( 1 /*exit-by-break*/ ){
    u32 serial_type;

    /* RHS is an integer */
    if( pRhs->flags & (MEM_Int|MEM_IntReal) ){
      testcase( pRhs->flags & MEM_Int );
      testcase( pRhs->flags & MEM_IntReal );
      serial_type = aKey1[idx1];
      testcase( serial_type==12 );
      if( serial_type>=10 ){
        rc = serial_type==10 ? -1 : +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else if( serial_type==7 ){
        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
        rc = -sqlite3IntFloatCompare(pRhs->u.i, mem1.u.r);
      }else{
        i64 lhs = vdbeRecordDecodeInt(serial_type, &aKey1[d1]);

    else if( pRhs->flags & MEM_Real ){
      serial_type = aKey1[idx1];
      if( serial_type>=10 ){
        /* Serial types 12 or greater are strings and blobs (greater than
        ** numbers). Types 10 and 11 are currently "reserved for future
        ** use", so it doesn't really matter what the results of comparing
        ** them to numberic values are.  */
        rc = serial_type==10 ? -1 : +1;
      }else if( serial_type==0 ){
        rc = -1;
      }else{
        sqlite3VdbeSerialGet(&aKey1[d1], serial_type, &mem1);
        if( serial_type==7 ){
          if( mem1.u.r<pRhs->u.r ){
            rc = -1;

        }
      }
    }

    /* RHS is null */
    else{
      serial_type = aKey1[idx1];
      rc = (serial_type!=0 && serial_type!=10);
    }

    if( rc!=0 ){
      int sortFlags = pPKey2->pKeyInfo->aSortFlags[i];
      if( sortFlags ){
        if( (sortFlags & KEYINFO_ORDER_BIGNULL)==0
         || ((sortFlags & KEYINFO_ORDER_DESC)

      return rc;
    }

    i++;
    if( i==pPKey2->nField ) break;
    pRhs++;
    d1 += sqlite3VdbeSerialTypeLen(serial_type);
    if( d1>(unsigned)nKey1 ) break;
    idx1 += sqlite3VarintLen(serial_type);
    if( idx1>=(unsigned)szHdr1 ){
      pPKey2->errCode = (u8)SQLITE_CORRUPT_BKPT;
      return 0;  /* Corrupt index */
    }
  }

  /* No memory allocation is ever used on mem1.  Prove this using
  ** the following assert().  If the assert() fails, it indicates a
  ** memory leak and a need to call sqlite3VdbeMemRelease(&mem1).  */
  assert( mem1.szMalloc==0 );

  /* rc==0 here means that one or both of the keys ran out of fields and

    }else if( pVal->flags & MEM_Str ){
      eType = SQLITE_TEXT;
    }
    assert( eType == aType[pVal->flags&MEM_AffMask] );
  }
#endif
  return aType[pVal->flags&MEM_AffMask];
}
SQLITE_API int sqlite3_value_encoding(sqlite3_value *pVal){
  return pVal->enc;
}

/* Return true if a parameter to xUpdate represents an unchanged column */
SQLITE_API int sqlite3_value_nochange(sqlite3_value *pVal){
  return (pVal->flags&(MEM_Null|MEM_Zero))==(MEM_Null|MEM_Zero);
}

  VdbeBranchTaken( (pIn1->flags & MEM_Null)!=0, 2);
  if( (pIn1->flags & MEM_Null)!=0 ){
    goto jump_to_p2;
  }
  break;
}

/* Opcode: IsType P1 P2 P3 P4 P5
** Synopsis: if typeof(P1.P3) in P5 goto P2
**
** Jump to P2 if the type of a column in a btree is one of the types specified
** by the P5 bitmask.
**
** P1 is normally a cursor on a btree for which the row decode cache is
** valid through at least column P3.  In other words, there should have been
** a prior OP_Column for column P3 or greater.  If the cursor is not valid,
** then this opcode might give spurious results.
** The the btree row has fewer than P3 columns, then use P4 as the
** datatype.
**
** If P1 is -1, then P3 is a register number and the datatype is taken
** from the value in that register.
**
** P5 is a bitmask of data types.  SQLITE_INTEGER is the least significant
** (0x01) bit. SQLITE_FLOAT is the 0x02 bit. SQLITE_TEXT is 0x04.
** SQLITE_BLOB is 0x08.  SQLITE_NULL is 0x10.
**
** Take the jump to address P2 if and only if the datatype of the
** value determined by P1 and P3 corresponds to one of the bits in the
** P5 bitmask.
**
*/
case OP_IsType: {        /* jump */
  VdbeCursor *pC;
  u16 typeMask;
  u32 serialType;

  assert( pOp->p1>=(-1) && pOp->p1<p->nCursor );
  assert( pOp->p1>=0 || (pOp->p3>=0 && pOp->p3<=(p->nMem+1 - p->nCursor)) );
  if( pOp->p1>=0 ){
    pC = p->apCsr[pOp->p1];
    assert( pC!=0 );
    assert( pOp->p3>=0 );
    if( pOp->p3<pC->nHdrParsed ){
      serialType = pC->aType[pOp->p3];
      if( serialType>=12 ){
        if( serialType&1 ){
          typeMask = 0x04;   /* SQLITE_TEXT */
        }else{
          typeMask = 0x08;   /* SQLITE_BLOB */
        }
      }else{
        static const unsigned char aMask[] = {
           0x10, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x2,
           0x01, 0x01, 0x10, 0x10
        };
        testcase( serialType==0 );
        testcase( serialType==1 );
        testcase( serialType==2 );
        testcase( serialType==3 );
        testcase( serialType==4 );
        testcase( serialType==5 );
        testcase( serialType==6 );
        testcase( serialType==7 );
        testcase( serialType==8 );
        testcase( serialType==9 );
        testcase( serialType==10 );
        testcase( serialType==11 );
        typeMask = aMask[serialType];
      }
    }else{
      typeMask = 1 << (pOp->p4.i - 1);
      testcase( typeMask==0x01 );
      testcase( typeMask==0x02 );
      testcase( typeMask==0x04 );
      testcase( typeMask==0x08 );
      testcase( typeMask==0x10 );
    }
  }else{
    assert( memIsValid(&aMem[pOp->p3]) );
    typeMask = 1 << (sqlite3_value_type((sqlite3_value*)&aMem[pOp->p3])-1);
    testcase( typeMask==0x01 );
    testcase( typeMask==0x02 );
    testcase( typeMask==0x04 );
    testcase( typeMask==0x08 );
    testcase( typeMask==0x10 );
  }
  VdbeBranchTaken( (typeMask & pOp->p5)!=0, 2);
  if( typeMask & pOp->p5 ){
    goto jump_to_p2;
  }
  break;
}

/* Opcode: ZeroOrNull P1 P2 P3 * *
** Synopsis: r[P2] = 0 OR NULL
**
** If all both registers P1 and P3 are NOT NULL, then store a zero in

/* Opcode: Column P1 P2 P3 P4 P5
** Synopsis: r[P3]=PX cursor P1 column P2
**
** Interpret the data that cursor P1 points to as a structure built using
** the MakeRecord instruction.  (See the MakeRecord opcode for additional
** information about the format of the data.)  Extract the P2-th column
** from this record.  If there are less than (P2+1)
** values in the record, extract a NULL.
**
** The value extracted is stored in register P3.
**
** If the record contains fewer than P2 fields, then extract a NULL.  Or,
** if the P4 argument is a P4_MEM use the value of the P4 argument as
** the result.
**
** If the OPFLAG_LENGTHARG bit is set in P5 then the result is guaranteed
** to only be used by the length() function or the equivalent.  The content
** of large blobs is not loaded, thus saving CPU cycles.  If the
** OPFLAG_TYPEOFARG bit is set then the result will only be used by the
** typeof() function or the IS NULL or IS NOT NULL operators or the
** equivalent.  In this case, all content loading can be omitted.
*/
case OP_Column: {
  u32 p2;            /* column number to retrieve */
  VdbeCursor *pC;    /* The VDBE cursor */
  BtCursor *pCrsr;   /* The B-Tree cursor corresponding to pC */
  u32 *aOffset;      /* aOffset[i] is offset to start of data for i-th column */
  int len;           /* The length of the serialized data for the column */

    assert( oc!=OP_SeekGT || r.default_rc==-1 );
    assert( oc!=OP_SeekLE || r.default_rc==-1 );
    assert( oc!=OP_SeekGE || r.default_rc==+1 );
    assert( oc!=OP_SeekLT || r.default_rc==+1 );

    r.aMem = &aMem[pOp->p3];
#ifdef SQLITE_DEBUG
    {
      int i;
      for(i=0; i<r.nField; i++){
        assert( memIsValid(&r.aMem[i]) );
        if( i>0 ) REGISTER_TRACE(pOp->p3+i, &r.aMem[i]);
      }
    }
#endif
    r.eqSeen = 0;
    rc = sqlite3BtreeIndexMoveto(pC->uc.pCursor, &r, &res);
    if( rc!=SQLITE_OK ){
      goto abort_due_to_error;
    }
    if( eqOnly && r.eqSeen==0 ){

    assert( pOp[1].opcode==OP_IdxLT || pOp[1].opcode==OP_IdxGT );
    pOp++; /* Skip the OP_IdxLt or OP_IdxGT that follows */
  }
  break;
}


/* Opcode: SeekScan  P1 P2 * * P5
** Synopsis: Scan-ahead up to P1 rows
**
** This opcode is a prefix opcode to OP_SeekGE.  In other words, this
** opcode must be immediately followed by OP_SeekGE. This constraint is
** checked by assert() statements.
**
** This opcode uses the P1 through P4 operands of the subsequent
** OP_SeekGE.  In the text that follows, the operands of the subsequent
** OP_SeekGE opcode are denoted as SeekOP.P1 through SeekOP.P4.   Only
** the P1, P2 and P5 operands of this opcode are also used, and  are called
** This.P1, This.P2 and This.P5.
**
** This opcode helps to optimize IN operators on a multi-column index
** where the IN operator is on the later terms of the index by avoiding
** unnecessary seeks on the btree, substituting steps to the next row
** of the b-tree instead.  A correct answer is obtained if this opcode
** is omitted or is a no-op.
**
** The SeekGE.P3 and SeekGE.P4 operands identify an unpacked key which
** is the desired entry that we want the cursor SeekGE.P1 to be pointing
** to.  Call this SeekGE.P3/P4 row the "target".
**
** If the SeekGE.P1 cursor is not currently pointing to a valid row,
** then this opcode is a no-op and control passes through into the OP_SeekGE.
**
** If the SeekGE.P1 cursor is pointing to a valid row, then that row
** might be the target row, or it might be near and slightly before the
** target row, or it might be after the target row.  If the cursor is
** currently before the target row, then this opcode attempts to position
** the cursor on or after the target row by invoking sqlite3BtreeStep()
** on the cursor between 1 and This.P1 times.
**
** The This.P5 parameter is a flag that indicates what to do if the
** cursor ends up pointing at a valid row that is past the target
** row.  If This.P5 is false (0) then a jump is made to SeekGE.P2.  If
** This.P5 is true (non-zero) then a jump is made to This.P2.  The P5==0
** case occurs when there are no inequality constraints to the right of
** the IN constraing.  The jump to SeekGE.P2 ends the loop.  The P5!=0 case
** occurs when there are inequality constraints to the right of the IN
** operator.  In that case, the This.P2 will point either directly to or
** to setup code prior to the OP_IdxGT or OP_IdxGE opcode that checks for
** loop terminate.
**
** Possible outcomes from this opcode:<ol>
**
** <li> If the cursor is initally not pointed to any valid row, then
**      fall through into the subsequent OP_SeekGE opcode.
**
** <li> If the cursor is left pointing to a row that is before the target
**      row, even after making as many as This.P1 calls to
**      sqlite3BtreeNext(), then also fall through into OP_SeekGE.
**
** <li> If the cursor is left pointing at the target row, either because it
**      was at the target row to begin with or because one or more
**      sqlite3BtreeNext() calls moved the cursor to the target row,
**      then jump to This.P2..,
**
** <li> If the cursor started out before the target row and a call to
**      to sqlite3BtreeNext() moved the cursor off the end of the index
**      (indicating that the target row definitely does not exist in the
**      btree) then jump to SeekGE.P2, ending the loop.
**
** <li> If the cursor ends up on a valid row that is past the target row
**      (indicating that the target row does not exist in the btree) then
**      jump to SeekOP.P2 if This.P5==0 or to This.P2 if This.P5>0.
** </ol>
*/
case OP_SeekScan: {
  VdbeCursor *pC;
  int res;
  int nStep;
  UnpackedRecord r;

  assert( pOp[1].opcode==OP_SeekGE );

  /* If pOp->p5 is clear, then pOp->p2 points to the first instruction past the
  ** OP_IdxGT that follows the OP_SeekGE. Otherwise, it points to the first
  ** opcode past the OP_SeekGE itself.  */
  assert( pOp->p2>=(int)(pOp-aOp)+2 );

#ifdef SQLITE_DEBUG
  if( pOp->p5==0 ){
    /* There are no inequality constraints following the IN constraint. */
    assert( pOp[1].p1==aOp[pOp->p2-1].p1 );
    assert( pOp[1].p2==aOp[pOp->p2-1].p2 );
    assert( pOp[1].p3==aOp[pOp->p2-1].p3 );
    assert( aOp[pOp->p2-1].opcode==OP_IdxGT
         || aOp[pOp->p2-1].opcode==OP_IdxGE );
    testcase( aOp[pOp->p2-1].opcode==OP_IdxGE );
  }else{
    /* There are inequality constraints.  */
    assert( pOp->p2==(int)(pOp-aOp)+2 );
    assert( aOp[pOp->p2-1].opcode==OP_SeekGE );
  }
#endif

  assert( pOp->p1>0 );
  pC = p->apCsr[pOp[1].p1];
  assert( pC!=0 );
  assert( pC->eCurType==CURTYPE_BTREE );
  assert( !pC->isTable );
  if( !sqlite3BtreeCursorIsValidNN(pC->uc.pCursor) ){

    }
  }
#endif
  res = 0;  /* Not needed.  Only used to silence a warning. */
  while(1){
    rc = sqlite3VdbeIdxKeyCompare(db, pC, &r, &res);
    if( rc ) goto abort_due_to_error;
    if( res>0 && pOp->p5==0 ){
      seekscan_search_fail:
      /* Jump to SeekGE.P2, ending the loop */
#ifdef SQLITE_DEBUG
      if( db->flags&SQLITE_VdbeTrace ){
        printf("... %d steps and then skip\n", pOp->p1 - nStep);
      }
#endif
      VdbeBranchTaken(1,3);
      pOp++;
      goto jump_to_p2;
    }
    if( res>=0 ){
      /* Jump to This.P2, bypassing the OP_SeekGE opcode */
#ifdef SQLITE_DEBUG
      if( db->flags&SQLITE_VdbeTrace ){
        printf("... %d steps and then success\n", pOp->p1 - nStep);
      }
#endif
      VdbeBranchTaken(2,3);
      goto jump_to_p2;

    pExpr = pExpr->pLeft;
    assert( pExpr!=0 );
  }
  op = pExpr->op;
  if( op==TK_REGISTER ) op = pExpr->op2;
  if( op==TK_COLUMN || op==TK_AGG_COLUMN ){
    assert( ExprUseYTab(pExpr) );
    assert( pExpr->y.pTab!=0 );
    return sqlite3TableColumnAffinity(pExpr->y.pTab, pExpr->iColumn);

  }
  if( op==TK_SELECT ){
    assert( ExprUseXSelect(pExpr) );
    assert( pExpr->x.pSelect!=0 );
    assert( pExpr->x.pSelect->pEList!=0 );
    assert( pExpr->x.pSelect->pEList->a[0].pExpr!=0 );
    return sqlite3ExprAffinity(pExpr->x.pSelect->pEList->a[0].pExpr);

  sqlite3 *db = pParse->db;
  CollSeq *pColl = 0;
  const Expr *p = pExpr;
  while( p ){
    int op = p->op;
    if( op==TK_REGISTER ) op = p->op2;
    if( op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_TRIGGER ){
      int j;
      assert( ExprUseYTab(p) );
      assert( p->y.pTab!=0 );


      if( (j = p->iColumn)>=0 ){

        const char *zColl = sqlite3ColumnColl(&p->y.pTab->aCol[j]);
        pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0);
      }
      break;

    }
    if( op==TK_CAST || op==TK_UPLUS ){
      p = p->pLeft;
      continue;
    }
    if( op==TK_VECTOR ){
      assert( ExprUseXList(p) );

  Table *pTab,    /* The table containing the value */
  int iTabCur,    /* The table cursor.  Or the PK cursor for WITHOUT ROWID */
  int iCol,       /* Index of the column to extract */
  int regOut      /* Extract the value into this register */
){
  Column *pCol;
  assert( v!=0 );
  assert( pTab!=0 );



  if( iCol<0 || iCol==pTab->iPKey ){
    sqlite3VdbeAddOp2(v, OP_Rowid, iTabCur, regOut);
    VdbeComment((v, "%s.rowid", pTab->zName));
  }else{
    int op;
    int x;
    if( IsVirtual(pTab) ){

      break;
    }
#endif /* !defined(SQLITE_UNTESTABLE) */
  }
  return target;
}

/*
** Check to see if pExpr is one of the indexed expressions on pParse->pIdxExpr.
** If it is, then resolve the expression by reading from the index and
** return the register into which the value has been read.  If pExpr is
** not an indexed expression, then return negative.
*/
static SQLITE_NOINLINE int sqlite3IndexedExprLookup(
  Parse *pParse,   /* The parsing context */
  Expr *pExpr,     /* The expression to potentially bypass */
  int target       /* Where to store the result of the expression */
){
  IndexedExpr *p;
  Vdbe *v;
  for(p=pParse->pIdxExpr; p; p=p->pIENext){
    int iDataCur = p->iDataCur;
    if( iDataCur<0 ) continue;
    if( pParse->iSelfTab ){
      if( p->iDataCur!=pParse->iSelfTab-1 ) continue;
      iDataCur = -1;
    }
    if( sqlite3ExprCompare(0, pExpr, p->pExpr, iDataCur)!=0 ) continue;
    v = pParse->pVdbe;
    assert( v!=0 );
    if( p->bMaybeNullRow ){
      /* If the index is on a NULL row due to an outer join, then we
      ** cannot extract the value from the index.  The value must be
      ** computed using the original expression. */
      int addr = sqlite3VdbeCurrentAddr(v);
      sqlite3VdbeAddOp3(v, OP_IfNullRow, p->iIdxCur, addr+3, target);
      VdbeCoverage(v);
      sqlite3VdbeAddOp3(v, OP_Column, p->iIdxCur, p->iIdxCol, target);
      VdbeComment((v, "%s expr-column %d", p->zIdxName, p->iIdxCol));
      sqlite3VdbeGoto(v, 0);
      p = pParse->pIdxExpr;
      pParse->pIdxExpr = 0;
      sqlite3ExprCode(pParse, pExpr, target);
      pParse->pIdxExpr = p;
      sqlite3VdbeJumpHere(v, addr+2);
    }else{
      sqlite3VdbeAddOp3(v, OP_Column, p->iIdxCur, p->iIdxCol, target);
      VdbeComment((v, "%s expr-column %d", p->zIdxName, p->iIdxCol));
    }
    return target;
  }
  return -1;  /* Not found */
}


/*
** Generate code into the current Vdbe to evaluate the given
** expression.  Attempt to store the results in register "target".
** Return the register where results are stored.
**
** With this routine, there is no guarantee that results will

  assert( target>0 && target<=pParse->nMem );
  assert( v!=0 );

expr_code_doover:
  if( pExpr==0 ){
    op = TK_NULL;
  }else if( pParse->pIdxExpr!=0
   && !ExprHasProperty(pExpr, EP_Leaf)
   && (r1 = sqlite3IndexedExprLookup(pParse, pExpr, target))>=0
  ){
    return r1;
  }else{
    assert( !ExprHasVVAProperty(pExpr,EP_Immutable) );
    op = pExpr->op;
  }
  switch( op ){
    case TK_AGG_COLUMN: {
      AggInfo *pAggInfo = pExpr->pAggInfo;

        ** expresssion.  However, make sure the constant has the correct
        ** datatype by applying the Affinity of the table column to the
        ** constant.
        */
        int aff;
        iReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft,target);
        assert( ExprUseYTab(pExpr) );
        assert( pExpr->y.pTab!=0 );
        aff = sqlite3TableColumnAffinity(pExpr->y.pTab, pExpr->iColumn);



        if( aff>SQLITE_AFF_BLOB ){
          static const char zAff[] = "B\000C\000D\000E";
          assert( SQLITE_AFF_BLOB=='A' );
          assert( SQLITE_AFF_TEXT=='B' );
          sqlite3VdbeAddOp4(v, OP_Affinity, iReg, 1, 0,
                            &zAff[(aff-'B')*2], P4_STATIC);
        }

        }else{
          /* Coding an expression that is part of an index where column names
          ** in the index refer to the table to which the index belongs */
          iTab = pParse->iSelfTab - 1;
        }
      }
      assert( ExprUseYTab(pExpr) );
      assert( pExpr->y.pTab!=0 );
      iReg = sqlite3ExprCodeGetColumn(pParse, pExpr->y.pTab,
                               pExpr->iColumn, iTab, target,
                               pExpr->op2);



      return iReg;
    }
    case TK_INTEGER: {
      codeInteger(pParse, pExpr, 0, target);
      return target;
    }
    case TK_TRUEFALSE: {

      break;
    }
    case TK_ISNULL:
    case TK_NOTNULL: {
      assert( TK_ISNULL==OP_IsNull );   testcase( op==TK_ISNULL );
      assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL );
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      sqlite3VdbeTypeofColumn(v, r1);
      sqlite3VdbeAddOp2(v, op, r1, dest);
      VdbeCoverageIf(v, op==TK_ISNULL);
      VdbeCoverageIf(v, op==TK_NOTNULL);
      testcase( regFree1==0 );
      break;
    }
    case TK_BETWEEN: {

      testcase( regFree1==0 );
      testcase( regFree2==0 );
      break;
    }
    case TK_ISNULL:
    case TK_NOTNULL: {
      r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, &regFree1);
      sqlite3VdbeTypeofColumn(v, r1);
      sqlite3VdbeAddOp2(v, op, r1, dest);
      testcase( op==TK_ISNULL );   VdbeCoverageIf(v, op==TK_ISNULL);
      testcase( op==TK_NOTNULL );  VdbeCoverageIf(v, op==TK_NOTNULL);
      testcase( regFree1==0 );
      break;
    }
    case TK_BETWEEN: {

  if( pA->op!=pB->op || pA->op==TK_RAISE ){
    if( pA->op==TK_COLLATE && sqlite3ExprCompare(pParse, pA->pLeft,pB,iTab)<2 ){
      return 1;
    }
    if( pB->op==TK_COLLATE && sqlite3ExprCompare(pParse, pA,pB->pLeft,iTab)<2 ){
      return 1;
    }
    if( pA->op==TK_AGG_COLUMN && pB->op==TK_COLUMN
     && pB->iTable<0 && pA->iTable==iTab
    ){
      /* fall through */
    }else{
      return 2;
    }
  }
  assert( !ExprHasProperty(pA, EP_IntValue) );
  assert( !ExprHasProperty(pB, EP_IntValue) );
  if( pA->u.zToken ){
    if( pA->op==TK_FUNCTION || pA->op==TK_AGG_FUNCTION ){
      if( sqlite3StrICmp(pA->u.zToken,pB->u.zToken)!=0 ) return 2;
#ifndef SQLITE_OMIT_WINDOWFUNC

      testcase( pExpr->op==TK_GT );
      testcase( pExpr->op==TK_GE );
      /* The y.pTab=0 assignment in wherecode.c always happens after the
      ** impliesNotNullRow() test */
      assert( pLeft->op!=TK_COLUMN || ExprUseYTab(pLeft) );
      assert( pRight->op!=TK_COLUMN || ExprUseYTab(pRight) );
      if( (pLeft->op==TK_COLUMN
           && ALWAYS(pLeft->y.pTab!=0)
           && IsVirtual(pLeft->y.pTab))
       || (pRight->op==TK_COLUMN
           && ALWAYS(pRight->y.pTab!=0)
           && IsVirtual(pRight->y.pTab))
      ){
        return WRC_Prune;
      }
      /* no break */ deliberate_fall_through
    }
    default:

){
  int i;           /* Index of column in the table */
  assert( k>=0 && k<pIdx->nColumn );
  i = pIdx->aiColumn[k];
  if( NEVER(i==XN_ROWID) ){
    VdbeComment((v,"%s.rowid",pIdx->zName));
  }else if( i==XN_EXPR ){
    assert( pIdx->bHasExpr );
    VdbeComment((v,"%s.expr(%d)",pIdx->zName, k));
  }else{
    VdbeComment((v,"%s.%s", pIdx->zName, pIdx->pTable->aCol[i].zCnName));
  }
}
#else
# define analyzeVdbeCommentIndexWithColumnName(a,b,c)

  p = sqlite3FindTable(db, zName, zDbase);
  if( p==0 ){
#ifndef SQLITE_OMIT_VIRTUALTABLE
    /* If zName is the not the name of a table in the schema created using
    ** CREATE, then check to see if it is the name of an virtual table that
    ** can be an eponymous virtual table. */
    if( (pParse->prepFlags & SQLITE_PREPARE_NO_VTAB)==0 && db->init.busy==0 ){
      Module *pMod = (Module*)sqlite3HashFind(&db->aModule, zName);
      if( pMod==0 && sqlite3_strnicmp(zName, "pragma_", 7)==0 ){
        pMod = sqlite3PragmaVtabRegister(db, zName);
      }
      if( pMod && sqlite3VtabEponymousTableInit(pParse, pMod) ){
        testcase( pMod->pEpoTab==0 );
        return pMod->pEpoTab;
      }
    }
#endif
    if( flags & LOCATE_NOERR ) return 0;
    pParse->checkSchema = 1;
  }else if( IsVirtual(p) && (pParse->prepFlags & SQLITE_PREPARE_NO_VTAB)!=0 ){
    p = 0;
  }

  if( p==0 ){
    const char *zMsg = flags & LOCATE_VIEW ? "no such view" : "no such table";
    if( zDbase ){
      sqlite3ErrorMsg(pParse, "%s: %s.%s", zMsg, zDbase, zName);

  }
  return 0;
}

/* Recompute the colNotIdxed field of the Index.
**
** colNotIdxed is a bitmask that has a 0 bit representing each indexed
** columns that are within the first 63 columns of the table and a 1 for
** all other bits (all columns that are not in the index).  The
** high-order bit of colNotIdxed is always 1.  All unindexed columns
** of the table have a 1.
**
** 2019-10-24:  For the purpose of this computation, virtual columns are
** not considered to be covered by the index, even if they are in the
** index, because we do not trust the logic in whereIndexExprTrans() to be
** able to find all instances of a reference to the indexed table column

    if( x>=0 && (pTab->aCol[x].colFlags & COLFLAG_VIRTUAL)==0 ){
      testcase( x==BMS-1 );
      testcase( x==BMS-2 );
      if( x<BMS-1 ) m |= MASKBIT(x);
    }
  }
  pIdx->colNotIdxed = ~m;
  assert( (pIdx->colNotIdxed>>63)==1 );  /* See note-20221022-a */
}

/*
** This routine runs at the end of parsing a CREATE TABLE statement that
** has a WITHOUT ROWID clause.  The job of this routine is to convert both
** internal schema data structures and the generated VDBE code so that they
** are appropriate for a WITHOUT ROWID table instead of a rowid table.

      if( pIndex->aColExpr==0 ){
        pIndex->aColExpr = pList;
        pList = 0;
      }
      j = XN_EXPR;
      pIndex->aiColumn[i] = XN_EXPR;
      pIndex->uniqNotNull = 0;
      pIndex->bHasExpr = 1;
    }else{
      j = pCExpr->iColumn;
      assert( j<=0x7fff );
      if( j<0 ){
        j = pTab->iPKey;
      }else{
        if( pTab->aCol[j].notNull==0 ){
          pIndex->uniqNotNull = 0;
        }
        if( pTab->aCol[j].colFlags & COLFLAG_VIRTUAL ){
          pIndex->bHasVCol = 1;
          pIndex->bHasExpr = 1;
        }
      }
      pIndex->aiColumn[i] = (i16)j;
    }
    zColl = 0;
    if( pListItem->pExpr->op==TK_COLLATE ){
      int nColl;

      ** first matching character and recursively continue the match from
      ** that point.
      **
      ** For a case-insensitive search, set variable cx to be the same as
      ** c but in the other case and search the input string for either
      ** c or cx.
      */
      if( c<0x80 ){
        char zStop[3];
        int bMatch;
        if( noCase ){
          zStop[0] = sqlite3Toupper(c);
          zStop[1] = sqlite3Tolower(c);
          zStop[2] = 0;
        }else{

}

/*
** The sqlite3_strglob() interface.  Return 0 on a match (like strcmp()) and
** non-zero if there is no match.
*/
SQLITE_API int sqlite3_strglob(const char *zGlobPattern, const char *zString){
  if( zString==0 ){
    return zGlobPattern!=0;
  }else if( zGlobPattern==0 ){
    return 1;
  }else {
    return patternCompare((u8*)zGlobPattern, (u8*)zString, &globInfo, '[');
  }
}

/*
** The sqlite3_strlike() interface.  Return 0 on a match and non-zero for
** a miss - like strcmp().
*/
SQLITE_API int sqlite3_strlike(const char *zPattern, const char *zStr, unsigned int esc){
  if( zStr==0 ){
    return zPattern!=0;
  }else if( zPattern==0 ){
    return 1;
  }else{
    return patternCompare((u8*)zPattern, (u8*)zStr, &likeInfoNorm, esc);
  }
}

/*
** 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
** only.
*/

      char aff;
      if( x>=0 ){
        aff = pTab->aCol[x].affinity;
      }else if( x==XN_ROWID ){
        aff = SQLITE_AFF_INTEGER;
      }else{
        assert( x==XN_EXPR );
        assert( pIdx->bHasExpr );
        assert( pIdx->aColExpr!=0 );
        aff = sqlite3ExprAffinity(pIdx->aColExpr->a[n].pExpr);
      }
      if( aff<SQLITE_AFF_BLOB ) aff = SQLITE_AFF_BLOB;
      if( aff>SQLITE_AFF_NUMERIC) aff = SQLITE_AFF_NUMERIC;
      pIdx->zColAff[n] = aff;
    }
    pIdx->zColAff[n] = 0;
  }

  return pIdx->zColAff;
}

/*
** Compute an affinity string for a table.   Space is obtained
** from sqlite3DbMalloc().  The caller is responsible for freeing
** the space when done.
*/
SQLITE_PRIVATE char *sqlite3TableAffinityStr(sqlite3 *db, const Table *pTab){
  char *zColAff;
  zColAff = (char *)sqlite3DbMallocRaw(db, pTab->nCol+1);
  if( zColAff ){
    int i, j;
    for(i=j=0; i<pTab->nCol; i++){
      if( (pTab->aCol[i].colFlags & COLFLAG_VIRTUAL)==0 ){
        zColAff[j++] = pTab->aCol[i].affinity;
      }
    }
    do{
      zColAff[j--] = 0;
    }while( j>=0 && zColAff[j]<=SQLITE_AFF_BLOB );
  }
  return zColAff;
}

/*
** Make changes to the evolving bytecode to do affinity transformations
** of values that are about to be gathered into a row for table pTab.
**
** For ordinary (legacy, non-strict) tables:
** -----------------------------------------

** the last opcode generated.  The new OP_TypeCheck needs to be inserted
** before the OP_MakeRecord.  The new OP_TypeCheck should use the same
** register set as the OP_MakeRecord.  If iReg>0 then register iReg is
** the first of a series of registers that will form the new record.
** Apply the type checking to that array of registers.
*/
SQLITE_PRIVATE void sqlite3TableAffinity(Vdbe *v, Table *pTab, int iReg){
  int i;
  char *zColAff;
  if( pTab->tabFlags & TF_Strict ){
    if( iReg==0 ){
      /* Move the previous opcode (which should be OP_MakeRecord) forward
      ** by one slot and insert a new OP_TypeCheck where the current
      ** OP_MakeRecord is found */
      VdbeOp *pPrev;

      sqlite3VdbeAddOp2(v, OP_TypeCheck, iReg, pTab->nNVCol);
      sqlite3VdbeAppendP4(v, pTab, P4_TABLE);
    }
    return;
  }
  zColAff = pTab->zColAff;
  if( zColAff==0 ){
    zColAff = sqlite3TableAffinityStr(0, pTab);

    if( !zColAff ){
      sqlite3OomFault(sqlite3VdbeDb(v));
      return;
    }










    pTab->zColAff = zColAff;
  }
  assert( zColAff!=0 );
  i = sqlite3Strlen30NN(zColAff);
  if( i ){
    if( iReg ){
      sqlite3VdbeAddOp4(v, OP_Affinity, iReg, i, 0, zColAff, i);

  /* Version 3.31.0 and later */
  sqlite3_int64 (*hard_heap_limit64)(sqlite3_int64);
  const char *(*uri_key)(const char*,int);
  const char *(*filename_database)(const char*);
  const char *(*filename_journal)(const char*);
  const char *(*filename_wal)(const char*);
  /* Version 3.32.0 and later */
  const char *(*create_filename)(const char*,const char*,const char*,
                           int,const char**);
  void (*free_filename)(const char*);
  sqlite3_file *(*database_file_object)(const char*);
  /* Version 3.34.0 and later */
  int (*txn_state)(sqlite3*,const char*);
  /* Version 3.36.1 and later */
  sqlite3_int64 (*changes64)(sqlite3*);
  sqlite3_int64 (*total_changes64)(sqlite3*);
  /* Version 3.37.0 and later */

  int (*vtab_in_next)(sqlite3_value*,sqlite3_value**);
  /* Version 3.39.0 and later */
  int (*deserialize)(sqlite3*,const char*,unsigned char*,
                     sqlite3_int64,sqlite3_int64,unsigned);
  unsigned char *(*serialize)(sqlite3*,const char *,sqlite3_int64*,
                              unsigned int);
  const char *(*db_name)(sqlite3*,int);
  /* Version 3.40.0 and later */
  int (*value_encoding)(sqlite3_value*);
};

/*
** This is the function signature used for all extension entry points.  It
** is also defined in the file "loadext.c".
*/
typedef int (*sqlite3_loadext_entry)(

#define sqlite3_vtab_in_next           sqlite3_api->vtab_in_next
/* Version 3.39.0 and later */
#ifndef SQLITE_OMIT_DESERIALIZE
#define sqlite3_deserialize            sqlite3_api->deserialize
#define sqlite3_serialize              sqlite3_api->serialize
#endif
#define sqlite3_db_name                sqlite3_api->db_name
/* Version 3.40.0 and later */
#define sqlite3_value_encoding         sqlite3_api->value_encoding
#endif /* !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION) */

#if !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
  /* 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;

#ifndef SQLITE_OMIT_DESERIALIZE
  sqlite3_deserialize,
  sqlite3_serialize,
#else
  0,
  0,
#endif
  sqlite3_db_name,
  /* Version 3.40.0 and later */
  sqlite3_value_type
};

/* True if x is the directory separator character
*/
#if SQLITE_OS_WIN
# define DirSep(X)  ((X)=='/'||(X)=='\\')
#else

      for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx, *pPk;
        Index *pPrior = 0;      /* Previous index */
        int loopTop;
        int iDataCur, iIdxCur;
        int r1 = -1;
        int bStrict;            /* True for a STRICT table */
        int r2;                 /* Previous key for WITHOUT ROWID tables */
        int mxCol;              /* Maximum non-virtual column number */

        if( !IsOrdinaryTable(pTab) ) continue;
        if( pObjTab && pObjTab!=pTab ) continue;
        if( isQuick || HasRowid(pTab) ){
          pPk = 0;
          r2 = 0;
        }else{

        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
          sqlite3VdbeAddOp2(v, OP_Integer, 0, 8+j); /* index entries counter */
        }
        assert( pParse->nMem>=8+j );
        assert( sqlite3NoTempsInRange(pParse,1,7+j) );
        sqlite3VdbeAddOp2(v, OP_Rewind, iDataCur, 0); VdbeCoverage(v);
        loopTop = sqlite3VdbeAddOp2(v, OP_AddImm, 7, 1);

        /* Fetch the right-most column from the table.  This will cause
        ** the entire record header to be parsed and sanity checked.  It
        ** will also prepopulate the cursor column cache that is used
        ** by the OP_IsType code, so it is a required step.
        */
        mxCol = pTab->nCol-1;
        while( mxCol>=0
            && ((pTab->aCol[mxCol].colFlags & COLFLAG_VIRTUAL)!=0
                || pTab->iPKey==mxCol) ) mxCol--;
        if( mxCol>=0 ){
          sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, mxCol, 3);
          sqlite3VdbeTypeofColumn(v, 3);
        }

        if( !isQuick ){
          if( pPk ){
            /* Verify WITHOUT ROWID keys are in ascending order */
            int a1;
            char *zErr;
            a1 = sqlite3VdbeAddOp4Int(v, OP_IdxGT, iDataCur, 0,r2,pPk->nKeyCol);
            VdbeCoverage(v);
            sqlite3VdbeAddOp1(v, OP_IsNull, r2); VdbeCoverage(v);
            zErr = sqlite3MPrintf(db,
                   "row not in PRIMARY KEY order for %s",
                    pTab->zName);
            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, zErr, P4_DYNAMIC);
            integrityCheckResultRow(v);
            sqlite3VdbeJumpHere(v, a1);
            sqlite3VdbeJumpHere(v, a1+1);
            for(j=0; j<pPk->nKeyCol; j++){
              sqlite3ExprCodeLoadIndexColumn(pParse, pPk, iDataCur, j, r2+j);
            }
          }
        }
        /* Verify datatypes for all columns:
        **
        **   (1) NOT NULL columns may not contain a NULL
        **   (2) Datatype must be exact for non-ANY columns in STRICT tables
        **   (3) Datatype for TEXT columns in non-STRICT tables must be
        **       NULL, TEXT, or BLOB.
        **   (4) Datatype for numeric columns in non-STRICT tables must not
        **       be a TEXT value that can be losslessly converted to numeric.
        */
        bStrict = (pTab->tabFlags & TF_Strict)!=0;
        for(j=0; j<pTab->nCol; j++){
          char *zErr;
          Column *pCol = pTab->aCol + j;  /* The column to be checked */
          int labelError;               /* Jump here to report an error */
          int labelOk;                  /* Jump here if all looks ok */
          int p1, p3, p4;               /* Operands to the OP_IsType opcode */
          int doTypeCheck;              /* Check datatypes (besides NOT NULL) */

          if( j==pTab->iPKey ) continue;
          if( bStrict ){
            doTypeCheck = pCol->eCType>COLTYPE_ANY;
          }else{
            doTypeCheck = pCol->affinity>SQLITE_AFF_BLOB;
          }
          if( pCol->notNull==0 && !doTypeCheck ) continue;

          /* Compute the operands that will be needed for OP_IsType */
          p4 = SQLITE_NULL;
          if( pCol->colFlags & COLFLAG_VIRTUAL ){
            sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, j, 3);
            p1 = -1;
            p3 = 3;
          }else{
            if( pCol->iDflt ){
              sqlite3_value *pDfltValue = 0;
              sqlite3ValueFromExpr(db, sqlite3ColumnExpr(pTab,pCol), ENC(db),
                                   pCol->affinity, &pDfltValue);
              if( pDfltValue ){
                p4 = sqlite3_value_type(pDfltValue);
                sqlite3ValueFree(pDfltValue);
              }
            }
            p1 = iDataCur;
            if( !HasRowid(pTab) ){
              testcase( j!=sqlite3TableColumnToStorage(pTab, j) );
              p3 = sqlite3TableColumnToIndex(sqlite3PrimaryKeyIndex(pTab), j);
            }else{
              p3 = sqlite3TableColumnToStorage(pTab,j);
              testcase( p3!=j);
            }
          }

          labelError = sqlite3VdbeMakeLabel(pParse);
          labelOk = sqlite3VdbeMakeLabel(pParse);
          if( pCol->notNull ){
            /* (1) NOT NULL columns may not contain a NULL */
            int jmp2 = sqlite3VdbeAddOp4Int(v, OP_IsType, p1, labelOk, p3, p4);
            sqlite3VdbeChangeP5(v, 0x0f);
            VdbeCoverage(v);
            zErr = sqlite3MPrintf(db, "NULL value in %s.%s", pTab->zName,
                                pCol->zCnName);
            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, zErr, P4_DYNAMIC);
            if( doTypeCheck ){
              sqlite3VdbeGoto(v, labelError);
              sqlite3VdbeJumpHere(v, jmp2);
            }else{

              /* VDBE byte code will fall thru */
            }

          }
          if( bStrict && doTypeCheck ){
            /* (2) Datatype must be exact for non-ANY columns in STRICT tables*/
            static unsigned char aStdTypeMask[] = {
               0x1f,    /* ANY */
               0x18,    /* BLOB */
               0x11,    /* INT */
               0x11,    /* INTEGER */
               0x13,    /* REAL */
               0x14     /* TEXT */
            };
            sqlite3VdbeAddOp4Int(v, OP_IsType, p1, labelOk, p3, p4);
            assert( pCol->eCType>=1 && pCol->eCType<=sizeof(aStdTypeMask) );
            sqlite3VdbeChangeP5(v, aStdTypeMask[pCol->eCType-1]);
            VdbeCoverage(v);
            zErr = sqlite3MPrintf(db, "non-%s value in %s.%s",
                                  sqlite3StdType[pCol->eCType-1],
                                  pTab->zName, pTab->aCol[j].zCnName);
            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, zErr, P4_DYNAMIC);
          }else if( !bStrict && pCol->affinity==SQLITE_AFF_TEXT ){
            /* (3) Datatype for TEXT columns in non-STRICT tables must be
            **     NULL, TEXT, or BLOB. */
            sqlite3VdbeAddOp4Int(v, OP_IsType, p1, labelOk, p3, p4);
            sqlite3VdbeChangeP5(v, 0x1c); /* NULL, TEXT, or BLOB */
            VdbeCoverage(v);
            zErr = sqlite3MPrintf(db, "NUMERIC value in %s.%s",
                                  pTab->zName, pTab->aCol[j].zCnName);
            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, zErr, P4_DYNAMIC);
          }else if( !bStrict && pCol->affinity>=SQLITE_AFF_NUMERIC ){
            /* (4) Datatype for numeric columns in non-STRICT tables must not
            **     be a TEXT value that can be converted to numeric. */
            sqlite3VdbeAddOp4Int(v, OP_IsType, p1, labelOk, p3, p4);
            sqlite3VdbeChangeP5(v, 0x1b); /* NULL, INT, FLOAT, or BLOB */
            VdbeCoverage(v);
            if( p1>=0 ){
              sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, j, 3);
            }
            sqlite3VdbeAddOp4(v, OP_Affinity, 3, 1, 0, "C", P4_STATIC);
            sqlite3VdbeAddOp4Int(v, OP_IsType, -1, labelOk, 3, p4);
            sqlite3VdbeChangeP5(v, 0x1c); /* NULL, TEXT, or BLOB */
            VdbeCoverage(v);
            zErr = sqlite3MPrintf(db, "TEXT value in %s.%s",
                                  pTab->zName, pTab->aCol[j].zCnName);
            sqlite3VdbeAddOp4(v, OP_String8, 0, 3, 0, zErr, P4_DYNAMIC);
          }
          sqlite3VdbeResolveLabel(v, labelError);
          integrityCheckResultRow(v);
          sqlite3VdbeResolveLabel(v, labelOk);

        }
        /* Verify CHECK constraints */
        if( pTab->pCheck && (db->flags & SQLITE_IgnoreChecks)==0 ){
          ExprList *pCheck = sqlite3ExprListDup(db, pTab->pCheck, 0);
          if( db->mallocFailed==0 ){
            int addrCkFault = sqlite3VdbeMakeLabel(pParse);
            int addrCkOk = sqlite3VdbeMakeLabel(pParse);

  /* For a long-term use prepared statement avoid the use of
  ** lookaside memory.
  */
  if( prepFlags & SQLITE_PREPARE_PERSISTENT ){
    sParse.disableLookaside++;
    DisableLookaside;
  }
  sParse.prepFlags = prepFlags & 0xff;

  /* Check to verify that it is possible to get a read lock on all
  ** database schemas.  The inability to get a read lock indicates that
  ** some other database connection is holding a write-lock, which in
  ** turn means that the other connection has made uncommitted changes
  ** to the schema.
  **

          testcase( db->flags & SQLITE_ReadUncommit );
          goto end_prepare;
        }
      }
    }
  }

#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( db->pDisconnect ) sqlite3VtabUnlockList(db);
#endif

  if( nBytes>=0 && (nBytes==0 || zSql[nBytes-1]!=0) ){
    char *zSqlCopy;
    int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
    testcase( nBytes==mxLen );
    testcase( nBytes==mxLen+1 );
    if( nBytes>mxLen ){

    case SRT_EphemTab: {
      int r1 = sqlite3GetTempRange(pParse, nPrefixReg+1);
      testcase( eDest==SRT_Table );
      testcase( eDest==SRT_EphemTab );
      testcase( eDest==SRT_Fifo );
      testcase( eDest==SRT_DistFifo );
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nResultCol, r1+nPrefixReg);
      if( pDest->zAffSdst ){
        sqlite3VdbeChangeP4(v, -1, pDest->zAffSdst, nResultCol);
      }
#ifndef SQLITE_OMIT_CTE
      if( eDest==SRT_DistFifo ){
        /* If the destination is DistFifo, then cursor (iParm+1) is open
        ** on an ephemeral index. If the current row is already present
        ** in the index, do not write it to the output. If not, add the
        ** current row to the index and proceed with writing it to the
        ** output table as well.  */

  sqlite3VdbeChangeP5(v, OPFLAG_PERMUTE);
  sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB); VdbeCoverage(v);

  /* Jump to the this point in order to terminate the query.
  */
  sqlite3VdbeResolveLabel(v, labelEnd);

  /* Make arrangements to free the 2nd and subsequent arms of the compound
  ** after the parse has finished */
  if( pSplit->pPrior ){
    sqlite3ParserAddCleanup(pParse,
       (void(*)(sqlite3*,void*))sqlite3SelectDelete, pSplit->pPrior);
  }
  pSplit->pPrior = pPrior;
  pPrior->pNext = pSplit;
  sqlite3ExprListDelete(db, pPrior->pOrderBy);

*/
typedef struct SubstContext {
  Parse *pParse;            /* The parsing context */
  int iTable;               /* Replace references to this table */
  int iNewTable;            /* New table number */
  int isOuterJoin;          /* Add TK_IF_NULL_ROW opcodes on each replacement */
  ExprList *pEList;         /* Replacement expressions */
  ExprList *pCList;         /* Collation sequences for replacement expr */
} SubstContext;

/* Forward Declarations */
static void substExprList(SubstContext*, ExprList*);
static void substSelect(SubstContext*, Select*, int);

/*

#ifdef SQLITE_ALLOW_ROWID_IN_VIEW
    if( pExpr->iColumn<0 ){
      pExpr->op = TK_NULL;
    }else
#endif
    {
      Expr *pNew;
      int iColumn = pExpr->iColumn;
      Expr *pCopy = pSubst->pEList->a[iColumn].pExpr;
      Expr ifNullRow;
      assert( pSubst->pEList!=0 && iColumn<pSubst->pEList->nExpr );
      assert( pExpr->pRight==0 );
      if( sqlite3ExprIsVector(pCopy) ){
        sqlite3VectorErrorMsg(pSubst->pParse, pCopy);
      }else{
        sqlite3 *db = pSubst->pParse->db;
        if( pSubst->isOuterJoin && pCopy->op!=TK_COLUMN ){
          memset(&ifNullRow, 0, sizeof(ifNullRow));

          pExpr->u.iValue = sqlite3ExprTruthValue(pExpr);
          pExpr->op = TK_INTEGER;
          ExprSetProperty(pExpr, EP_IntValue);
        }

        /* Ensure that the expression now has an implicit collation sequence,
        ** just as it did when it was a column of a view or sub-query. */
        {
          CollSeq *pNat = sqlite3ExprCollSeq(pSubst->pParse, pExpr);
          CollSeq *pColl = sqlite3ExprCollSeq(pSubst->pParse,
                pSubst->pCList->a[iColumn].pExpr
          );
          if( pNat!=pColl || (pExpr->op!=TK_COLUMN && pExpr->op!=TK_COLLATE) ){
            pExpr = sqlite3ExprAddCollateString(pSubst->pParse, pExpr,
                (pColl ? pColl->zName : "BINARY")
            );
          }
        }
        ExprClearProperty(pExpr, EP_Collate);
      }
    }
  }else{
    if( pExpr->op==TK_IF_NULL_ROW && pExpr->iTable==pSubst->iTable ){
      pExpr->iTable = pSubst->iNewTable;

  memset(&w, 0, sizeof(w));
  w.u.aiCol = aCsrMap;
  w.xExprCallback = renumberCursorsCb;
  w.xSelectCallback = sqlite3SelectWalkNoop;
  sqlite3WalkSelect(&w, p);
}
#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */

/*
** If pSel is not part of a compound SELECT, return a pointer to its
** expression list. Otherwise, return a pointer to the expression list
** of the leftmost SELECT in the compound.
*/
static ExprList *findLeftmostExprlist(Select *pSel){
  while( pSel->pPrior ){
    pSel = pSel->pPrior;
  }
  return pSel->pEList;
}

#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
/*
** This routine attempts to flatten subqueries as a performance optimization.
** This routine returns 1 if it makes changes and 0 if no flattening occurs.
**
** To understand the concept of flattening, consider the following

**              (17d1) aggregate, or
**              (17d2) DISTINCT
**        (17e) the subquery may not contain window functions, and
**        (17f) the subquery must not be the RHS of a LEFT JOIN.
**        (17g) either the subquery is the first element of the outer
**              query or there are no RIGHT or FULL JOINs in any arm
**              of the subquery.  (This is a duplicate of condition (27b).)
**        (17h) The corresponding result set expressions in all arms of the
**              compound must have the same affinity.
**
**        The parent and sub-query may contain WHERE clauses. Subject to
**        rules (11), (13) and (14), they may also contain ORDER BY,
**        LIMIT and OFFSET clauses.  The subquery cannot use any compound
**        operator other than UNION ALL because all the other compound
**        operators have an implied DISTINCT which is disallowed by
**        restriction (4).

  /* Restriction (17): If the sub-query is a compound SELECT, then it must
  ** use only the UNION ALL operator. And none of the simple select queries
  ** that make up the compound SELECT are allowed to be aggregate or distinct
  ** queries.
  */
  if( pSub->pPrior ){
    int ii;
    if( pSub->pOrderBy ){
      return 0;  /* Restriction (20) */
    }
    if( isAgg || (p->selFlags & SF_Distinct)!=0 || isOuterJoin>0 ){
      return 0; /* (17d1), (17d2), or (17f) */
    }
    for(pSub1=pSub; pSub1; pSub1=pSub1->pPrior){

        return 0;   /* Restrictions (17g), (27b) */
      }
      testcase( pSub1->pSrc->nSrc>1 );
    }

    /* Restriction (18). */
    if( p->pOrderBy ){

      for(ii=0; ii<p->pOrderBy->nExpr; ii++){
        if( p->pOrderBy->a[ii].u.x.iOrderByCol==0 ) return 0;
      }
    }

    /* Restriction (23) */
    if( (p->selFlags & SF_Recursive) ) return 0;

    /* Restriction (17h) */
    for(ii=0; ii<pSub->pEList->nExpr; ii++){
      char aff;
      assert( pSub->pEList->a[ii].pExpr!=0 );
      aff = sqlite3ExprAffinity(pSub->pEList->a[ii].pExpr);
      for(pSub1=pSub->pPrior; pSub1; pSub1=pSub1->pPrior){
        assert( pSub1->pEList!=0 );
        assert( pSub1->pEList->nExpr>ii );
        assert( pSub1->pEList->a[ii].pExpr!=0 );
        if( sqlite3ExprAffinity(pSub1->pEList->a[ii].pExpr)!=aff ){
          return 0;
        }
      }
    }

    if( pSrc->nSrc>1 ){
      if( pParse->nSelect>500 ) return 0;
      if( OptimizationDisabled(db, SQLITE_FlttnUnionAll) ) return 0;
      aCsrMap = sqlite3DbMallocZero(db, ((i64)pParse->nTab+1)*sizeof(int));
      if( aCsrMap ) aCsrMap[0] = pParse->nTab;
    }

    if( db->mallocFailed==0 ){
      SubstContext x;
      x.pParse = pParse;
      x.iTable = iParent;
      x.iNewTable = iNewParent;
      x.isOuterJoin = isOuterJoin;
      x.pEList = pSub->pEList;
      x.pCList = findLeftmostExprlist(pSub);
      substSelect(&x, pParent, 0);
    }

    /* The flattened query is a compound if either the inner or the
    ** outer query is a compound. */
    pParent->selFlags |= pSub->selFlags & SF_Compound;
    assert( (pSub->selFlags & SF_Distinct)==0 ); /* restriction (17b) */

    /*
    ** SELECT ... FROM (SELECT ... LIMIT a OFFSET b) LIMIT x OFFSET y;
    **
    ** One is tempted to try to add a and b to combine the limits.  But this
    ** does not work if either limit is negative.
    */
    if( pSub->pLimit ){
      pParent->pLimit = pSub->pLimit;
      pSub->pLimit = 0;
    }

    /* Recompute the SrcItem.colUsed masks for the flattened
    ** tables. */
    for(i=0; i<nSubSrc; i++){
      recomputeColumnsUsed(pParent, &pSrc->a[i+iFrom]);
    }
  }

  /* Finially, delete what is left of the subquery and return

**          all window-functions used by the sub-query. It is safe to
**          filter out entire partitions, as this does not change the
**          window over which any window-function is calculated.
**
**   (7) The inner query is a Common Table Expression (CTE) that should
**       be materialized.  (This restriction is implemented in the calling
**       routine.)
**
**   (8) The subquery may not be a compound that uses UNION, INTERSECT,
**       or EXCEPT.  (We could, perhaps, relax this restriction to allow
**       this case if none of the comparisons operators between left and
**       right arms of the compound use a collation other than BINARY.
**       But it is a lot of work to check that case for an obscure and
**       minor optimization, so we omit it for now.)
**
** Return 0 if no changes are made and non-zero if one or more WHERE clause
** terms are duplicated into the subquery.
*/
static int pushDownWhereTerms(
  Parse *pParse,        /* Parse context (for malloc() and error reporting) */
  Select *pSubq,        /* The subquery whose WHERE clause is to be augmented */
  Expr *pWhere,         /* The WHERE clause of the outer query */
  SrcItem *pSrc         /* The subquery term of the outer FROM clause */
){
  Expr *pNew;
  int nChng = 0;
  if( pWhere==0 ) return 0;
  if( pSubq->selFlags & (SF_Recursive|SF_MultiPart) ) return 0;
  if( pSrc->fg.jointype & (JT_LTORJ|JT_RIGHT) ) return 0;

#ifndef SQLITE_OMIT_WINDOWFUNC
  if( pSubq->pPrior ){
    Select *pSel;
    for(pSel=pSubq; pSel; pSel=pSel->pPrior){
      u8 op = pSel->op;
      assert( op==TK_ALL || op==TK_SELECT
           || op==TK_UNION || op==TK_INTERSECT || op==TK_EXCEPT );
      if( op!=TK_ALL && op!=TK_SELECT ) return 0;  /* restriction (8) */
      if( pSel->pWin ) return 0;    /* restriction (6b) */
    }
  }else{
    if( pSubq->pWin && pSubq->pWin->pPartition==0 ) return 0;
  }
#endif

      pNew = sqlite3ExprDup(pParse->db, pWhere, 0);
      unsetJoinExpr(pNew, -1, 1);
      x.pParse = pParse;
      x.iTable = pSrc->iCursor;
      x.iNewTable = pSrc->iCursor;
      x.isOuterJoin = 0;
      x.pEList = pSubq->pEList;
      x.pCList = findLeftmostExprlist(pSubq);
      pNew = substExpr(&x, pNew);
#ifndef SQLITE_OMIT_WINDOWFUNC
      if( pSubq->pWin && 0==pushDownWindowCheck(pParse, pSubq, pNew) ){
        /* Restriction 6c has prevented push-down in this case */
        sqlite3ExprDelete(pParse->db, pNew);
        nChng--;
        break;

      pParse->pWith = pWith->pOuter;
    }
  }
}
#endif

/*
** The SrcItem structure passed as the second argument represents a
** sub-query in the FROM clause of a SELECT statement. This function
** allocates and populates the SrcItem.pTab object. If successful,
** SQLITE_OK is returned. Otherwise, if an OOM error is encountered,
** SQLITE_NOMEM.
*/
SQLITE_PRIVATE int sqlite3ExpandSubquery(Parse *pParse, SrcItem *pFrom){
  Select *pSel = pFrom->pSelect;
  Table *pTab;

    sqlite3TreeViewSelect(0, p, 0);
  }
#endif
}

/*
** Check to see if the pThis entry of pTabList is a self-join of a prior view.
** If it is, then return the SrcItem for the prior view.  If it is not,
** then return 0.
*/
static SrcItem *isSelfJoinView(
  SrcList *pTabList,           /* Search for self-joins in this FROM clause */
  SrcItem *pThis               /* Search for prior reference to this subquery */
){
  SrcItem *pItem;

        onceAddr = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
        VdbeComment((v, "materialize %!S", pItem));
      }else{
        VdbeNoopComment((v, "materialize %!S", pItem));
      }
      sqlite3SelectDestInit(&dest, SRT_EphemTab, pItem->iCursor);
      ExplainQueryPlan((pParse, 1, "MATERIALIZE %!S", pItem));
      dest.zAffSdst = sqlite3TableAffinityStr(db, pItem->pTab);
      sqlite3Select(pParse, pSub, &dest);
      sqlite3DbFree(db, dest.zAffSdst);
      dest.zAffSdst = 0;
      pItem->pTab->nRowLogEst = pSub->nSelectRow;
      if( onceAddr ) sqlite3VdbeJumpHere(v, onceAddr);
      sqlite3VdbeAddOp2(v, OP_Return, pItem->regReturn, topAddr+1);
      VdbeComment((v, "end %!S", pItem));
      sqlite3VdbeJumpHere(v, topAddr);
      sqlite3ClearTempRegCache(pParse);
      if( pItem->fg.isCte && pItem->fg.isCorrelated==0 ){

      ** This might involve two separate loops with an OP_Sort in between, or
      ** it might be a single loop that uses an index to extract information
      ** in the right order to begin with.
      */
      sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
      SELECTTRACE(1,pParse,p,("WhereBegin\n"));
      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, pDistinct,
          p, (sDistinct.isTnct==2 ? WHERE_DISTINCTBY : WHERE_GROUPBY)
          |  (orderByGrp ? WHERE_SORTBYGROUP : 0) | distFlag, 0
      );
      if( pWInfo==0 ){
        sqlite3ExprListDelete(db, pDistinct);
        goto select_end;
      }
      eDist = sqlite3WhereIsDistinct(pWInfo);

        ** be an appropriate ORDER BY expression for the optimization.
        */
        assert( minMaxFlag==WHERE_ORDERBY_NORMAL || pMinMaxOrderBy!=0 );
        assert( pMinMaxOrderBy==0 || pMinMaxOrderBy->nExpr==1 );

        SELECTTRACE(1,pParse,p,("WhereBegin\n"));
        pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pMinMaxOrderBy,
                                   pDistinct, p, minMaxFlag|distFlag, 0);
        if( pWInfo==0 ){
          goto select_end;
        }
        SELECTTRACE(1,pParse,p,("WhereBegin returns\n"));
        eDist = sqlite3WhereIsDistinct(pWInfo);
        updateAccumulator(pParse, regAcc, pAggInfo, eDist);
        if( eDist!=WHERE_DISTINCT_NOOP ){

  memset(&sNC, 0, sizeof(sNC));
  sNC.pParse = &sSubParse;
  sSubParse.pTriggerTab = pTab;
  sSubParse.pToplevel = pTop;
  sSubParse.zAuthContext = pTrigger->zName;
  sSubParse.eTriggerOp = pTrigger->op;
  sSubParse.nQueryLoop = pParse->nQueryLoop;
  sSubParse.prepFlags = pParse->prepFlags;

  v = sqlite3GetVdbe(&sSubParse);
  if( v ){
    VdbeComment((v, "Start: %s.%s (%s %s%s%s ON %s)",
      pTrigger->zName, onErrorText(orconf),
      (pTrigger->tr_tm==TRIGGER_BEFORE ? "BEFORE" : "AFTER"),
        (pTrigger->op==TK_UPDATE ? "UPDATE" : ""),

**
** If column as REAL affinity and the table is an ordinary b-tree table
** (not a virtual table) then the value might have been stored as an
** integer.  In that case, add an OP_RealAffinity opcode to make sure
** it has been converted into REAL.
*/
SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *v, Table *pTab, int i, int iReg){
  Column *pCol;
  assert( pTab!=0 );
  assert( pTab->nCol>i );
  pCol = &pTab->aCol[i];
  if( pCol->iDflt ){
    sqlite3_value *pValue = 0;
    u8 enc = ENC(sqlite3VdbeDb(v));
    assert( !IsView(pTab) );
    VdbeComment((v, "%s.%s", pTab->zName, pCol->zCnName));
    assert( i<pTab->nCol );
    sqlite3ValueFromExpr(sqlite3VdbeDb(v),
                         sqlite3ColumnExpr(pTab,pCol), enc,
                         pCol->affinity, &pValue);
    if( pValue ){
      sqlite3VdbeAppendP4(v, pValue, P4_MEM);
    }
  }
#ifndef SQLITE_OMIT_FLOATING_POINT
  if( pCol->affinity==SQLITE_AFF_REAL && !IsVirtual(pTab) ){
    sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg);
  }
#endif
}

/*
** Check to see if column iCol of index pIdx references any of the

      nn = pIdx->nKeyCol;
      for(ii=0; ii<nn; ii++){
        Expr *pExpr;
        sCol[0].u.zToken = (char*)pIdx->azColl[ii];
        if( pIdx->aiColumn[ii]==XN_EXPR ){
          assert( pIdx->aColExpr!=0 );
          assert( pIdx->aColExpr->nExpr>ii );
          assert( pIdx->bHasExpr );
          pExpr = pIdx->aColExpr->a[ii].pExpr;
          if( pExpr->op!=TK_COLLATE ){
            sCol[0].pLeft = pExpr;
            pExpr = &sCol[0];
          }
        }else{
          sCol[0].pLeft = &sCol[1];

  u8 saved_mTrace;        /* Saved trace settings */
  Db *pDb = 0;            /* Database to detach at end of vacuum */
  int isMemDb;            /* True if vacuuming a :memory: database */
  int nRes;               /* Bytes of reserved space at the end of each page */
  int nDb;                /* Number of attached databases */
  const char *zDbMain;    /* Schema name of database to vacuum */
  const char *zOut;       /* Name of output file */
  u32 pgflags = PAGER_SYNCHRONOUS_OFF; /* sync flags for output db */

  if( !db->autoCommit ){
    sqlite3SetString(pzErrMsg, db, "cannot VACUUM from within a transaction");
    return SQLITE_ERROR; /* IMP: R-12218-18073 */
  }
  if( db->nVdbeActive>1 ){
    sqlite3SetString(pzErrMsg, db,"cannot VACUUM - SQL statements in progress");

    i64 sz = 0;
    if( id->pMethods!=0 && (sqlite3OsFileSize(id, &sz)!=SQLITE_OK || sz>0) ){
      rc = SQLITE_ERROR;
      sqlite3SetString(pzErrMsg, db, "output file already exists");
      goto end_of_vacuum;
    }
    db->mDbFlags |= DBFLAG_VacuumInto;

    /* For a VACUUM INTO, the pager-flags are set to the same values as
    ** they are for the database being vacuumed, except that PAGER_CACHESPILL
    ** is always set. */
    pgflags = db->aDb[iDb].safety_level | (db->flags & PAGER_FLAGS_MASK);
  }
  nRes = sqlite3BtreeGetRequestedReserve(pMain);

  sqlite3BtreeSetCacheSize(pTemp, db->aDb[iDb].pSchema->cache_size);
  sqlite3BtreeSetSpillSize(pTemp, sqlite3BtreeSetSpillSize(pMain,0));
  sqlite3BtreeSetPagerFlags(pTemp, pgflags|PAGER_CACHESPILL);

  /* Begin a transaction and take an exclusive lock on the main database
  ** file. This is done before the sqlite3BtreeGetPageSize(pMain) call below,
  ** to ensure that we do not try to change the page-size on a WAL database.
  */
  rc = execSql(db, pzErrMsg, "BEGIN");
  if( rc!=SQLITE_OK ) goto end_of_vacuum;

  int rc = 0;

  /* Check to see the left operand is a column in a virtual table */
  if( NEVER(pExpr==0) ) return pDef;
  if( pExpr->op!=TK_COLUMN ) return pDef;
  assert( ExprUseYTab(pExpr) );
  pTab = pExpr->y.pTab;
  if( NEVER(pTab==0) ) return pDef;
  if( !IsVirtual(pTab) ) return pDef;
  pVtab = sqlite3GetVTable(db, pTab)->pVtab;
  assert( pVtab!=0 );
  assert( pVtab->pModule!=0 );
  pMod = (sqlite3_module *)pVtab->pModule;
  if( pMod->xFindFunction==0 ) return pDef;

};

/*
** An instance of the following structure keeps track of a mapping
** between VDBE cursor numbers and bits of the bitmasks in WhereTerm.
**
** The VDBE cursor numbers are small integers contained in
** SrcItem.iCursor and Expr.iTable fields.  For any given WHERE
** clause, the cursor numbers might not begin with 0 and they might
** contain gaps in the numbering sequence.  But we want to make maximum
** use of the bits in our bitmasks.  This structure provides a mapping
** from the sparse cursor numbers into consecutive integers beginning
** with 0.
**
** If WhereMaskSet.ix[A]==B it means that The A-th bit of a Bitmask

#ifndef SQLITE_QUERY_PLANNER_LIMIT
# define SQLITE_QUERY_PLANNER_LIMIT 20000
#endif
#ifndef SQLITE_QUERY_PLANNER_LIMIT_INCR
# define SQLITE_QUERY_PLANNER_LIMIT_INCR 1000
#endif















/*
** 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 of the query */
#if WHERETRACE_ENABLED
  Expr *pWhere;             /* The complete WHERE clause */


#endif
  Select *pSelect;          /* The entire SELECT statement containing WHERE */
  int aiCurOnePass[2];      /* OP_OpenWrite cursors for the ONEPASS opt */
  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 */
  u16 wctrlFlags;           /* Flags originally passed to sqlite3WhereBegin() */
  LogEst iLimit;            /* LIMIT if wctrlFlags has WHERE_USE_LIMIT */
  u8 nLevel;                /* Number of nested loop */
  i8 nOBSat;                /* Number of ORDER BY terms satisfied by indices */
  u8 eOnePass;              /* ONEPASS_OFF, or _SINGLE, or _MULTI */
  u8 eDistinct;             /* One of the WHERE_DISTINCT_* values */
  unsigned bDeferredSeek :1;   /* Uses OP_DeferredSeek */
  unsigned untestedTerms :1;   /* Not all WHERE terms resolved by outer loop */
  unsigned bOrderedInnerLoop:1;/* True if only the inner-most loop is ordered */
  unsigned sorted :1;          /* True if really sorted (not just grouped) */
  LogEst nRowOut;           /* Estimated number of output rows */
  int iTop;                 /* The very beginning of the WHERE loop */
  int iEndWhere;            /* End of the WHERE clause itself */
  WhereLoop *pLoops;        /* List of all WhereLoop objects */

  WhereMemBlock *pMemToFree;/* Memory to free when this object destroyed */
  Bitmask revMask;          /* Mask of ORDER BY terms that need reversing */
  WhereClause sWC;          /* Decomposition of the WHERE clause */
  WhereMaskSet sMaskSet;    /* Map cursor numbers to bitmasks */
  WhereLevel a[1];          /* Information about each nest loop in WHERE */
};

    }
  }else{
    assert( nReg==1 || pParse->nErr );
    sqlite3ExprCode(pParse, p, iReg);
  }
}










































































































































/*
** The pTruth expression is always true because it is the WHERE clause
** a partial index that is driving a query loop.  Look through all of the
** WHERE clause terms on the query, and if any of those terms must be
** true because pTruth is true, then mark those WHERE clause terms as
** coded.
*/

      WhereTerm *pTerm = pLoop->aLTerm[0];
      int regRowid;
      assert( pTerm!=0 );
      assert( pTerm->pExpr!=0 );
      testcase( pTerm->wtFlags & TERM_VIRTUAL );
      regRowid = sqlite3GetTempReg(pParse);
      regRowid = codeEqualityTerm(pParse, pTerm, pLevel, 0, 0, regRowid);
      sqlite3VdbeAddOp2(pParse->pVdbe, OP_MustBeInt, regRowid, addrNxt);
      VdbeCoverage(pParse->pVdbe);
      sqlite3VdbeAddOp4Int(pParse->pVdbe, OP_Filter, pLevel->regFilter,
                           addrNxt, regRowid, 1);
      VdbeCoverage(pParse->pVdbe);
    }else{
      u16 nEq = pLoop->u.btree.nEq;
      int r1;
      char *zStartAff;

      }else{
        Expr *pRight = pTerm->pExpr->pRight;
        codeExprOrVector(pParse, pRight, iTarget, 1);
        if( pTerm->eMatchOp==SQLITE_INDEX_CONSTRAINT_OFFSET
         && pLoop->u.vtab.bOmitOffset
        ){
          assert( pTerm->eOperator==WO_AUX );
          assert( pWInfo->pSelect!=0 );
          assert( pWInfo->pSelect->iOffset>0 );
          sqlite3VdbeAddOp2(v, OP_Integer, 0, pWInfo->pSelect->iOffset);
          VdbeComment((v,"Zero OFFSET counter"));
        }
      }
    }
    sqlite3VdbeAddOp2(v, OP_Integer, pLoop->u.vtab.idxNum, iReg);
    sqlite3VdbeAddOp2(v, OP_Integer, nConstraint, iReg+1);
    sqlite3VdbeAddOp4(v, OP_VFilter, iCur, addrNotFound, iReg,

    assert( pTerm->pExpr!=0 );
    testcase( pTerm->wtFlags & TERM_VIRTUAL );
    iReleaseReg = ++pParse->nMem;
    iRowidReg = codeEqualityTerm(pParse, pTerm, pLevel, 0, bRev, iReleaseReg);
    if( iRowidReg!=iReleaseReg ) sqlite3ReleaseTempReg(pParse, iReleaseReg);
    addrNxt = pLevel->addrNxt;
    if( pLevel->regFilter ){
      sqlite3VdbeAddOp2(v, OP_MustBeInt, iRowidReg, addrNxt);
      VdbeCoverage(v);
      sqlite3VdbeAddOp4Int(v, OP_Filter, pLevel->regFilter, addrNxt,
                           iRowidReg, 1);
      VdbeCoverage(v);
      filterPullDown(pParse, pWInfo, iLevel, addrNxt, notReady);
    }
    sqlite3VdbeAddOp3(v, OP_SeekRowid, iCur, addrNxt, iRowidReg);
    VdbeCoverage(v);

        ** should we try before giving up and going with a seek.  The cost
        ** of a seek is proportional to the logarithm of the of the number
        ** of entries in the tree, so basing the number of steps to try
        ** on the estimated number of rows in the btree seems like a good
        ** guess. */
        addrSeekScan = sqlite3VdbeAddOp1(v, OP_SeekScan,
                                         (pIdx->aiRowLogEst[0]+9)/10);
        if( pRangeStart ){
          sqlite3VdbeChangeP5(v, 1);
          sqlite3VdbeChangeP2(v, addrSeekScan, sqlite3VdbeCurrentAddr(v)+1);
          addrSeekScan = 0;
        }
        VdbeCoverage(v);
      }
      sqlite3VdbeAddOp4Int(v, op, iIdxCur, addrNxt, regBase, nConstraint);
      VdbeCoverage(v);
      VdbeCoverageIf(v, op==OP_Rewind);  testcase( op==OP_Rewind );
      VdbeCoverageIf(v, op==OP_Last);    testcase( op==OP_Last );
      VdbeCoverageIf(v, op==OP_SeekGT);  testcase( op==OP_SeekGT );

        sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, k, iRowidReg+j);
      }
      sqlite3VdbeAddOp4Int(v, OP_NotFound, iCur, addrCont,
                           iRowidReg, pPk->nKeyCol); VdbeCoverage(v);
    }

    if( pLevel->iLeftJoin==0 ){





















      /* If a partial index is driving the loop, try to eliminate WHERE clause
      ** terms from the query that must be true due to the WHERE clause of
      ** the partial index.
      **
      ** 2019-11-02 ticket 623eff57e76d45f6: This optimization does not work
      ** for a LEFT JOIN.
      */

    ** 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().
    */
    if( pWInfo->nLevel>1 ){
      int nNotReady;                 /* The number of notReady tables */
      SrcItem *origSrc;              /* Original list of tables */
      nNotReady = pWInfo->nLevel - iLevel - 1;
      pOrTab = sqlite3DbMallocRawNN(db,
                            sizeof(*pOrTab)+ nNotReady*sizeof(pOrTab->a[0]));
      if( pOrTab==0 ) return notReady;
      pOrTab->nAlloc = (u8)(nNotReady + 1);
      pOrTab->nSrc = pOrTab->nAlloc;
      memcpy(pOrTab->a, pTabItem, sizeof(*pTabItem));
      origSrc = pWInfo->pTabList->a;
      for(k=1; k<=nNotReady; k++){

    ** loop to point to this spot, which is the top of the next containing
    ** loop.  The byte-code formatter will use that P2 value as a hint to
    ** indent everything in between the this point and the final OP_Return.
    ** See tag-20220407a in vdbe.c and shell.c */
    assert( pLevel->op==OP_Return );
    pLevel->p2 = sqlite3VdbeCurrentAddr(v);

    if( pWInfo->nLevel>1 ){ sqlite3DbFreeNN(db, pOrTab); }
    if( !untestedTerms ) disableTerm(pLevel, pTerm);
  }else
#endif /* SQLITE_OMIT_OR_OPTIMIZATION */

  {
    /* Case 6:  There is no usable index.  We must do a complete
    **          scan of the entire table.

        **    2019-06-10 https://sqlite.org/src/info/fd76310a5e843e07
        **    2019-06-14 https://sqlite.org/src/info/ce8717f0885af975
        **    2019-09-03 https://sqlite.org/src/info/0f0428096f17252a
        */
        if( pLeft->op!=TK_COLUMN
         || sqlite3ExprAffinity(pLeft)!=SQLITE_AFF_TEXT
         || (ALWAYS( ExprUseYTab(pLeft) )
             && ALWAYS(pLeft->y.pTab)
             && IsVirtual(pLeft->y.pTab))  /* Might be numeric */
        ){
          int isNum;
          double rDummy;
          isNum = sqlite3AtoF(zNew, &rDummy, iTo, SQLITE_UTF8);
          if( isNum<=0 ){
            if( iTo==1 && zNew[0]=='-' ){

    ** virtual table on their second argument, which is the same as
    ** the left-hand side operand in their in-fix form.
    **
    **       vtab_column MATCH expression
    **       MATCH(expression,vtab_column)
    */
    pCol = pList->a[1].pExpr;
    assert( pCol->op!=TK_COLUMN || (ExprUseYTab(pCol) && pCol->y.pTab!=0) );

    if( ExprIsVtab(pCol) ){
      for(i=0; i<ArraySize(aOp); i++){
        assert( !ExprHasProperty(pExpr, EP_IntValue) );
        if( sqlite3StrICmp(pExpr->u.zToken, aOp[i].zOp)==0 ){
          *peOp2 = aOp[i].eOp2;
          *ppRight = pList->a[0].pExpr;
          *ppLeft = pCol;

    **
    ** Historically, xFindFunction expected to see lower-case function
    ** names.  But for this use case, xFindFunction is expected to deal
    ** with function names in an arbitrary case.
    */
    pCol = pList->a[0].pExpr;
    assert( pCol->op!=TK_COLUMN || ExprUseYTab(pCol) );
    assert( pCol->op!=TK_COLUMN || (ExprUseYTab(pCol) && pCol->y.pTab!=0) );
    if( ExprIsVtab(pCol) ){
      sqlite3_vtab *pVtab;
      sqlite3_module *pMod;
      void (*xNotUsed)(sqlite3_context*,int,sqlite3_value**);
      void *pNotUsed;
      pVtab = sqlite3GetVTable(db, pCol->y.pTab)->pVtab;
      assert( pVtab!=0 );

        }
      }
    }
  }else if( pExpr->op==TK_NE || pExpr->op==TK_ISNOT || pExpr->op==TK_NOTNULL ){
    int res = 0;
    Expr *pLeft = pExpr->pLeft;
    Expr *pRight = pExpr->pRight;
    assert( pLeft->op!=TK_COLUMN || (ExprUseYTab(pLeft) && pLeft->y.pTab!=0) );

    if( ExprIsVtab(pLeft) ){
      res++;
    }
    assert( pRight==0 || pRight->op!=TK_COLUMN
            || (ExprUseYTab(pRight) && pRight->y.pTab!=0) );
    if( pRight && ExprIsVtab(pRight) ){
      res++;
      SWAP(Expr*, pLeft, pRight);
    }
    *ppLeft = pLeft;
    *ppRight = pRight;
    if( pExpr->op==TK_NE ) *peOp2 = SQLITE_INDEX_CONSTRAINT_NE;

  int iCur;
  for(i=0; mPrereq>1; i++, mPrereq>>=1){}
  iCur = pFrom->a[i].iCursor;
  for(pIdx=pFrom->a[i].pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    if( pIdx->aColExpr==0 ) continue;
    for(i=0; i<pIdx->nKeyCol; i++){
      if( pIdx->aiColumn[i]!=XN_EXPR ) continue;
      assert( pIdx->bHasExpr );
      if( sqlite3ExprCompareSkip(pExpr, pIdx->aColExpr->a[i].pExpr, iCur)==0 ){
        aiCurCol[0] = iCur;
        aiCurCol[1] = XN_EXPR;
        return 1;
      }
    }
  }

**   5. The ORDER BY clause, if any, will be made available to the xBestIndex
**      method.
**
** LIMIT and OFFSET terms are ignored by most of the planner code. They
** exist only so that they may be passed to the xBestIndex method of the
** single virtual table in the FROM clause of the SELECT.
*/
SQLITE_PRIVATE void SQLITE_NOINLINE sqlite3WhereAddLimit(WhereClause *pWC, Select *p){
  assert( p!=0 && p->pLimit!=0 );                 /* 1 -- checked by caller */
  if( p->pGroupBy==0

   && (p->selFlags & (SF_Distinct|SF_Aggregate))==0             /* 2 */
   && (p->pSrc->nSrc==1 && IsVirtual(p->pSrc->a[0].pTab))       /* 3 */
  ){
    ExprList *pOrderBy = p->pOrderBy;
    int iCsr = p->pSrc->a[0].iCursor;
    int ii;

  assert( db!=0 );
  sqlite3WhereClauseClear(&pWInfo->sWC);
  while( pWInfo->pLoops ){
    WhereLoop *p = pWInfo->pLoops;
    pWInfo->pLoops = p->pNextLoop;
    whereLoopDelete(db, p);
  }

  while( pWInfo->pMemToFree ){
    WhereMemBlock *pNext = pWInfo->pMemToFree->pNext;
    sqlite3DbNNFreeNN(db, pWInfo->pMemToFree);
    pWInfo->pMemToFree = pNext;
  }
  sqlite3DbNNFreeNN(db, pWInfo);
}












/*
** Return TRUE if all of the following are true:
**
**   (1)  X has the same or lower cost, or returns the same or fewer rows,
**        than Y.
**   (2)  X uses fewer WHERE clause terms than Y
**   (3)  Every WHERE clause term used by X is also used by Y

     && (pTerm->wtFlags & TERM_VNULL)==0
    ){
      return 1;
    }
  }
  return 0;
}

/*
** Structure passed to the whereIsCoveringIndex Walker callback.
*/
struct CoveringIndexCheck {
  Index *pIdx;       /* The index */
  int iTabCur;       /* Cursor number for the corresponding table */
};

/*
** Information passed in is pWalk->u.pCovIdxCk.  Call is pCk.
**
** If the Expr node references the table with cursor pCk->iTabCur, then
** make sure that column is covered by the index pCk->pIdx.  We know that
** all columns less than 63 (really BMS-1) are covered, so we don't need
** to check them.  But we do need to check any column at 63 or greater.
**
** If the index does not cover the column, then set pWalk->eCode to
** non-zero and return WRC_Abort to stop the search.
**
** If this node does not disprove that the index can be a covering index,
** then just return WRC_Continue, to continue the search.
*/
static int whereIsCoveringIndexWalkCallback(Walker *pWalk, Expr *pExpr){
  int i;                  /* Loop counter */
  const Index *pIdx;      /* The index of interest */
  const i16 *aiColumn;    /* Columns contained in the index */
  u16 nColumn;            /* Number of columns in the index */
  if( pExpr->op!=TK_COLUMN && pExpr->op!=TK_AGG_COLUMN ) return WRC_Continue;
  if( pExpr->iColumn<(BMS-1) ) return WRC_Continue;
  if( pExpr->iTable!=pWalk->u.pCovIdxCk->iTabCur ) return WRC_Continue;
  pIdx = pWalk->u.pCovIdxCk->pIdx;
  aiColumn = pIdx->aiColumn;
  nColumn = pIdx->nColumn;
  for(i=0; i<nColumn; i++){
    if( aiColumn[i]==pExpr->iColumn ) return WRC_Continue;
  }
  pWalk->eCode = 1;
  return WRC_Abort;
}


/*
** pIdx is an index that covers all of the low-number columns used by
** pWInfo->pSelect (columns from 0 through 62).  But there are columns
** in pWInfo->pSelect beyond 62.  This routine tries to answer the question
** of whether pIdx covers *all* columns in the query.
**
** Return 0 if pIdx is a covering index.   Return non-zero if pIdx is
** not a covering index or if we are unable to determine if pIdx is a
** covering index.
**
** This routine is an optimization.  It is always safe to return non-zero.
** But returning zero when non-zero should have been returned can lead to
** incorrect bytecode and assertion faults.
*/
static SQLITE_NOINLINE u32 whereIsCoveringIndex(
  WhereInfo *pWInfo,     /* The WHERE clause context */
  Index *pIdx,           /* Index that is being tested */
  int iTabCur            /* Cursor for the table being indexed */
){
  int i;
  struct CoveringIndexCheck ck;
  Walker w;
  if( pWInfo->pSelect==0 ){
    /* We don't have access to the full query, so we cannot check to see
    ** if pIdx is covering.  Assume it is not. */
    return 1;
  }
  for(i=0; i<pIdx->nColumn; i++){
    if( pIdx->aiColumn[i]>=BMS-1 ) break;
  }
  if( i>=pIdx->nColumn ){
    /* pIdx does not index any columns greater than 62, but we know from
    ** colMask that columns greater than 62 are used, so this is not a
    ** covering index */
    return 1;
  }
  ck.pIdx = pIdx;
  ck.iTabCur = iTabCur;
  memset(&w, 0, sizeof(w));
  w.xExprCallback = whereIsCoveringIndexWalkCallback;
  w.xSelectCallback = sqlite3SelectWalkNoop;
  w.u.pCovIdxCk = &ck;
  w.eCode = 0;
  sqlite3WalkSelect(&w, pWInfo->pSelect);
  return w.eCode;
}

/*
** Add all WhereLoop objects for a single table of the join where the table
** is identified by pBuilder->pNew->iTab.  That table is guaranteed to be
** a b-tree table, not a virtual table.
**
** The costs (WhereLoop.rRun) of the b-tree loops added by this function

    }else{
      Bitmask m;
      if( pProbe->isCovering ){
        pNew->wsFlags = WHERE_IDX_ONLY | WHERE_INDEXED;
        m = 0;
      }else{
        m = pSrc->colUsed & pProbe->colNotIdxed;
        if( m==TOPBIT ){
          m = whereIsCoveringIndex(pWInfo, pProbe, pSrc->iCursor);
        }
        pNew->wsFlags = (m==0) ? (WHERE_IDX_ONLY|WHERE_INDEXED) : WHERE_INDEXED;
      }

      /* Full scan via index */
      if( b
       || !HasRowid(pTab)
       || pProbe->pPartIdxWhere!=0

** Return SQLITE_OK on success or SQLITE_NOMEM of a memory allocation
** error occurs.
*/
static int wherePathSolver(WhereInfo *pWInfo, LogEst nRowEst){
  int mxChoice;             /* Maximum number of simultaneous paths tracked */
  int nLoop;                /* Number of terms in the join */
  Parse *pParse;            /* Parsing context */

  int iLoop;                /* Loop counter over the terms of the join */
  int ii, jj;               /* Loop counters */
  int mxI = 0;              /* Index of next entry to replace */
  int nOrderBy;             /* Number of ORDER BY clause terms */
  LogEst mxCost = 0;        /* Maximum cost of a set of paths */
  LogEst mxUnsorted = 0;    /* Maximum unsorted cost of a set of path */
  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 */
  LogEst *aSortCost = 0;    /* Sorting and partial sorting costs */
  char *pSpace;             /* Temporary memory used by this routine */
  int nSpace;               /* Bytes of space allocated at pSpace */

  pParse = pWInfo->pParse;

  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.  (nRowEst=%d)\n", nRowEst));

  }else{
    nOrderBy = pWInfo->pOrderBy->nExpr;
  }

  /* Allocate and initialize space for aTo, aFrom and aSortCost[] */
  nSpace = (sizeof(WherePath)+sizeof(WhereLoop*)*nLoop)*mxChoice*2;
  nSpace += sizeof(LogEst) * nOrderBy;
  pSpace = sqlite3StackAllocRawNN(pParse->db, nSpace);
  if( pSpace==0 ) return SQLITE_NOMEM_BKPT;
  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;

    aTo = aFrom;
    aFrom = pFrom;
    nFrom = nTo;
  }

  if( nFrom==0 ){
    sqlite3ErrorMsg(pParse, "no query solution");
    sqlite3StackFreeNN(pParse->db, pSpace);
    return SQLITE_ERROR;
  }

  /* Find the lowest cost path.  pFrom will be left pointing to that path */
  pFrom = aFrom;
  for(ii=1; ii<nFrom; ii++){
    if( pFrom->rCost>aFrom[ii].rCost ) pFrom = &aFrom[ii];

    }
  }


  pWInfo->nRowOut = pFrom->nRow;

  /* Free temporary memory and return success */

  sqlite3StackFreeNN(pParse->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

           pLoop->cId, (double)sqlite3LogEstToInt(nSearch), pTab->zName,
           (double)sqlite3LogEstToInt(pTab->nRowLogEst)));
      }
    }
    nSearch += pLoop->nOut;
  }
}

/*
** This is an sqlite3ParserAddCleanup() callback that is invoked to
** free the Parse->pIdxExpr list when the Parse object is destroyed.
*/
static void whereIndexedExprCleanup(sqlite3 *db, void *pObject){
  Parse *pParse = (Parse*)pObject;
  while( pParse->pIdxExpr!=0 ){
    IndexedExpr *p = pParse->pIdxExpr;
    pParse->pIdxExpr = p->pIENext;
    sqlite3ExprDelete(db, p->pExpr);
    sqlite3DbFreeNN(db, p);
  }
}

/*
** The index pIdx is used by a query and contains one or more expressions.
** In other words pIdx is an index on an expression.  iIdxCur is the cursor
** number for the index and iDataCur is the cursor number for the corresponding
** table.
**
** This routine adds IndexedExpr entries to the Parse->pIdxExpr field for
** each of the expressions in the index so that the expression code generator
** will know to replace occurrences of the indexed expression with
** references to the corresponding column of the index.
*/
static SQLITE_NOINLINE void whereAddIndexedExpr(
  Parse *pParse,     /* Add IndexedExpr entries to pParse->pIdxExpr */
  Index *pIdx,       /* The index-on-expression that contains the expressions */
  int iIdxCur,       /* Cursor number for pIdx */
  SrcItem *pTabItem  /* The FROM clause entry for the table */
){
  int i;
  IndexedExpr *p;
  Table *pTab;
  assert( pIdx->bHasExpr );
  pTab = pIdx->pTable;
  for(i=0; i<pIdx->nColumn; i++){
    Expr *pExpr;
    int j = pIdx->aiColumn[i];
    int bMaybeNullRow;
    if( j==XN_EXPR ){
      pExpr = pIdx->aColExpr->a[i].pExpr;
      testcase( pTabItem->fg.jointype & JT_LEFT );
      testcase( pTabItem->fg.jointype & JT_RIGHT );
      testcase( pTabItem->fg.jointype & JT_LTORJ );
      bMaybeNullRow = (pTabItem->fg.jointype & (JT_LEFT|JT_LTORJ|JT_RIGHT))!=0;
    }else if( j>=0 && (pTab->aCol[j].colFlags & COLFLAG_VIRTUAL)!=0 ){
      pExpr = sqlite3ColumnExpr(pTab, &pTab->aCol[j]);
      bMaybeNullRow = 0;
    }else{
      continue;
    }
    if( sqlite3ExprIsConstant(pExpr) ) continue;
    p = sqlite3DbMallocRaw(pParse->db,  sizeof(IndexedExpr));
    if( p==0 ) break;
    p->pIENext = pParse->pIdxExpr;
    p->pExpr = sqlite3ExprDup(pParse->db, pExpr, 0);
    p->iDataCur = pTabItem->iCursor;
    p->iIdxCur = iIdxCur;
    p->iIdxCol = i;
    p->bMaybeNullRow = bMaybeNullRow;
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
    p->zIdxName = pIdx->zName;
#endif
    pParse->pIdxExpr = p;
    if( p->pIENext==0 ){
      sqlite3ParserAddCleanup(pParse, whereIndexedExprCleanup, pParse);
    }
  }
}

/*
** Generate the beginning of the loop used for WHERE clause processing.
** The return value is a pointer to an opaque structure that contains
** information needed to terminate the loop.  Later, the calling routine
** should invoke sqlite3WhereEnd() with the return value of this function
** in order to complete the WHERE clause processing.

*/
SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
  Parse *pParse,          /* The parser context */
  SrcList *pTabList,      /* FROM clause: A list of all tables to be scanned */
  Expr *pWhere,           /* The WHERE clause */
  ExprList *pOrderBy,     /* An ORDER BY (or GROUP BY) clause, or NULL */
  ExprList *pResultSet,   /* Query result set.  Req'd for DISTINCT */
  Select *pSelect,        /* The entire SELECT statement */
  u16 wctrlFlags,         /* The WHERE_* flags defined in sqliteInt.h */
  int iAuxArg             /* If WHERE_OR_SUBCLAUSE is set, index cursor number
                          ** If WHERE_USE_LIMIT, then the limit amount */
){
  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 */

    sqlite3DbFree(db, pWInfo);
    pWInfo = 0;
    goto whereBeginError;
  }
  pWInfo->pParse = pParse;
  pWInfo->pTabList = pTabList;
  pWInfo->pOrderBy = pOrderBy;
#if WHERETRACE_ENABLED
  pWInfo->pWhere = pWhere;
#endif
  pWInfo->pResultSet = pResultSet;
  pWInfo->aiCurOnePass[0] = pWInfo->aiCurOnePass[1] = -1;
  pWInfo->nLevel = nTabList;
  pWInfo->iBreak = pWInfo->iContinue = sqlite3VdbeMakeLabel(pParse);
  pWInfo->wctrlFlags = wctrlFlags;
  pWInfo->iLimit = iAuxArg;
  pWInfo->savedNQueryLoop = pParse->nQueryLoop;

  pWInfo->pSelect = pSelect;

  memset(&pWInfo->nOBSat, 0,
         offsetof(WhereInfo,sWC) - offsetof(WhereInfo,nOBSat));
  memset(&pWInfo->a[0], 0, sizeof(WhereLoop)+nTabList*sizeof(WhereLevel));
  assert( pWInfo->eOnePass==ONEPASS_OFF );  /* ONEPASS defaults to OFF */
  pMaskSet = &pWInfo->sMaskSet;
  pMaskSet->n = 0;
  pMaskSet->ix[0] = -99; /* Initialize ix[0] to a value that can never be

      }
    }
  #endif
  }

  /* Analyze all of the subexpressions. */
  sqlite3WhereExprAnalyze(pTabList, &pWInfo->sWC);
  if( pSelect && pSelect->pLimit ){
    sqlite3WhereAddLimit(&pWInfo->sWC, pSelect);
  }
  if( pParse->nErr ) goto whereBeginError;

  /* Special case: WHERE terms that do not refer to any tables in the join
  ** (constant expressions). Evaluate each such term, and jump over all the
  ** generated code if the result is not true.
  **
  ** Do not do this if the expression contains non-deterministic functions

        op = OP_OpenWrite;
        pWInfo->aiCurOnePass[1] = iIndexCur;
      }else if( iAuxArg && (wctrlFlags & WHERE_OR_SUBCLAUSE)!=0 ){
        iIndexCur = iAuxArg;
        op = OP_ReopenIdx;
      }else{
        iIndexCur = pParse->nTab++;
        if( pIx->bHasExpr && OptimizationEnabled(db, SQLITE_IndexedExpr) ){
          whereAddIndexedExpr(pParse, pIx, iIndexCur, pTabItem);
        }
      }
      pLevel->iIdxCur = iIndexCur;
      assert( pIx!=0 );
      assert( pIx->pSchema==pTab->pSchema );
      assert( iIndexCur>=0 );
      if( op ){
        sqlite3VdbeAddOp3(v, op, iIndexCur, pIx->tnum, iDb);

  VdbeModuleComment((v, "Begin WHERE-core"));
  pWInfo->iEndWhere = sqlite3VdbeCurrentAddr(v);
  return pWInfo;

  /* Jump here if malloc fails */
whereBeginError:
  if( pWInfo ){


    pParse->nQueryLoop = pWInfo->savedNQueryLoop;
    whereInfoFree(db, pWInfo);
  }
  return 0;
}

/*

      sqlite3VdbeJumpHere(v, addr);
    }
    VdbeModuleComment((v, "End WHERE-loop%d: %s", i,
                     pWInfo->pTabList->a[pLevel->iFrom].pTab->zName));
  }

  assert( pWInfo->nLevel<=pTabList->nSrc );

  for(i=0, pLevel=pWInfo->a; i<pWInfo->nLevel; i++, pLevel++){
    int k, last;
    VdbeOp *pOp, *pLastOp;
    Index *pIdx = 0;
    SrcItem *pTabItem = &pTabList->a[pLevel->iFrom];
    Table *pTab = pTabItem->pTab;
    assert( pTab!=0 );

    if( pIdx
     && !db->mallocFailed
    ){
      if( pWInfo->eOnePass==ONEPASS_OFF || !HasRowid(pIdx->pTable) ){
        last = iEnd;
      }else{
        last = pWInfo->iEndWhere;
      }
      if( pIdx->bHasExpr ){
        IndexedExpr *p = pParse->pIdxExpr;
        while( p ){
          if( p->iIdxCur==pLevel->iIdxCur ){
            p->iDataCur = -1;
            p->iIdxCur = -1;
          }
          p = p->pIENext;
        }
      }
      k = pLevel->addrBody + 1;
#ifdef SQLITE_DEBUG
      if( db->flags & SQLITE_VdbeAddopTrace ){
        printf("TRANSLATE opcodes in range %d..%d\n", k, last-1);
      }
      /* Proof that the "+1" on the k value above is safe */

  createCollation(db, sqlite3StrBINARY, SQLITE_UTF16LE, 0, binCollFunc, 0);
  createCollation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc, 0);
  createCollation(db, "RTRIM", SQLITE_UTF8, 0, rtrimCollFunc, 0);
  if( db->mallocFailed ){
    goto opendb_out;
  }

#if SQLITE_OS_UNIX && defined(SQLITE_OS_KV_OPTIONAL)
  /* Process magic filenames ":localStorage:" and ":sessionStorage:" */
  if( zFilename && zFilename[0]==':' ){
    if( strcmp(zFilename, ":localStorage:")==0 ){
      zFilename = "file:local?vfs=kvvfs";
      flags |= SQLITE_OPEN_URI;
    }else if( strcmp(zFilename, ":sessionStorage:")==0 ){
      zFilename = "file:session?vfs=kvvfs";
      flags |= SQLITE_OPEN_URI;
    }
  }
#endif /* SQLITE_OS_UNIX && defined(SQLITE_OS_KV_OPTIONAL) */

  /* Parse the filename/URI argument
  **
  ** Only allow sensible combinations of bits in the flags argument.
  ** Throw an error if any non-sense combination is used.  If we
  ** do not block illegal combinations here, it could trigger
  ** assert() statements in deeper layers.  Sensible combinations
  ** are:

  }
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_NOMEM ) sqlite3OomFault(db);
    sqlite3ErrorWithMsg(db, rc, zErrMsg ? "%s" : 0, zErrMsg);
    sqlite3_free(zErrMsg);
    goto opendb_out;
  }
  assert( db->pVfs!=0 );
#if SQLITE_OS_KV || defined(SQLITE_OS_KV_OPTIONAL)
  if( sqlite3_stricmp(db->pVfs->zName, "kvvfs")==0 ){
    db->temp_store = 2;
  }
#endif

  /* Open the backend database driver */
  rc = sqlite3BtreeOpen(db->pVfs, zOpen, db, &db->aDb[0].pBt, 0,
                        flags | SQLITE_OPEN_MAIN_DB);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_IOERR_NOMEM ){
      rc = SQLITE_NOMEM_BKPT;

** and query parameters.  The pointer returned is valid for use by
** sqlite3_filename_database() and sqlite3_uri_parameter() and related
** functions.
**
** Memory layout must be compatible with that generated by the pager
** and expected by sqlite3_uri_parameter() and databaseName().
*/
SQLITE_API const char *sqlite3_create_filename(
  const char *zDatabase,
  const char *zJournal,
  const char *zWal,
  int nParam,
  const char **azParam
){
  sqlite3_int64 nByte;

}

/*
** Free memory obtained from sqlite3_create_filename().  It is a severe
** error to call this routine with any parameter other than a pointer
** previously obtained from sqlite3_create_filename() or a NULL pointer.
*/
SQLITE_API void sqlite3_free_filename(const char *p){
  if( p==0 ) return;
  p = databaseName(p);
  sqlite3_free((char*)p - 4);
}


/*
** This is a utility routine, useful to VFS implementations, that checks
** to see if a database file was a URI that contained a specific query
** parameter, and if so obtains the value of the query parameter.

/*
** Recover as many snapshots as possible from the wal file associated with
** schema zDb of database db.
*/
SQLITE_API int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb){
  int rc = SQLITE_ERROR;

#ifndef SQLITE_OMIT_WAL
  int iDb;

#ifdef SQLITE_ENABLE_API_ARMOR
  if( !sqlite3SafetyCheckOk(db) ){
    return SQLITE_MISUSE_BKPT;
  }
#endif

    ** since the write might do a rebalance which would disrupt the read
    ** cursor. */
    return SQLITE_LOCKED_VTAB;
  }
  rtreeReference(pRtree);
  assert(nData>=1);

  memset(&cell, 0, sizeof(cell));

  /* Constraint handling. A write operation on an r-tree table may return
  ** SQLITE_CONSTRAINT for two reasons:
  **
  **   1. A duplicate rowid value, or
  **   2. The supplied data violates the "x2>=x1" constraint.
  **

#define SQLITE_RBU_STATE_OAL        1
#define SQLITE_RBU_STATE_MOVE       2
#define SQLITE_RBU_STATE_CHECKPOINT 3
#define SQLITE_RBU_STATE_DONE       4
#define SQLITE_RBU_STATE_ERROR      5

SQLITE_API int sqlite3rbu_state(sqlite3rbu *pRbu);

/*
** As part of applying an RBU update or performing an RBU vacuum operation,
** the system must at one point move the *-oal file to the equivalent *-wal
** path. Normally, it does this by invoking POSIX function rename(2) directly.
** Except on WINCE platforms, where it uses win32 API MoveFileW(). This
** function may be used to register a callback that the RBU module will invoke
** instead of one of these APIs.
**
** If a callback is registered with an RBU handle, it invokes it instead
** of rename(2) when it needs to move a file within the file-system. The
** first argument passed to the xRename() callback is a copy of the second
** argument (pArg) passed to this function. The second is the full path
** to the file to move and the third the full path to which it should be
** moved. The callback function should return SQLITE_OK to indicate
** success. If an error occurs, it should return an SQLite error code.
** In this case the RBU operation will be abandoned and the error returned
** to the RBU user.
**
** Passing a NULL pointer in place of the xRename argument to this function
** restores the default behaviour.
*/
SQLITE_API void sqlite3rbu_rename_handler(
  sqlite3rbu *pRbu,
  void *pArg,
  int (*xRename)(void *pArg, const char *zOld, const char *zNew)
);


/*
** Create an RBU VFS named zName that accesses the underlying file-system
** via existing VFS zParent. Or, if the zParent parameter is passed NULL,
** then the new RBU VFS uses the default system VFS to access the file-system.
** The new object is registered as a non-default VFS with SQLite before
** returning.

  int nProgress;                  /* Rows processed for all objects */
  RbuObjIter objiter;             /* Iterator for skipping through tbl/idx */
  const char *zVfsName;           /* Name of automatically created rbu vfs */
  rbu_file *pTargetFd;            /* File handle open on target db */
  int nPagePerSector;             /* Pages per sector for pTargetFd */
  i64 iOalSz;
  i64 nPhaseOneStep;
  void *pRenameArg;
  int (*xRename)(void*, const char*, const char*);

  /* The following state variables are used as part of the incremental
  ** checkpoint stage (eStage==RBU_STAGE_CKPT). See comments surrounding
  ** function rbuSetupCheckpoint() for details.  */
  u32 iMaxFrame;                  /* Largest iWalFrame value in aFrame[] */
  u32 mLock;
  int nFrame;                     /* Entries in aFrame[] array */

    dbMain = rbuOpenDbhandle(p, p->zTarget, 1);
    if( dbMain ){
      assert( p->rc==SQLITE_OK );
      p->rc = rbuLockDatabase(dbMain);
    }

    if( p->rc==SQLITE_OK ){




      p->rc = p->xRename(p->pRenameArg, zOal, zWal);





















    }

    if( p->rc!=SQLITE_OK
     || rbuIsVacuum(p)
     || rbuExclusiveCheckpoint(dbMain)==0
    ){
      sqlite3_close(dbMain);

  p = (sqlite3rbu*)sqlite3_malloc64(nByte);
  if( p ){
    RbuState *pState = 0;

    /* Create the custom VFS. */
    memset(p, 0, sizeof(sqlite3rbu));
    sqlite3rbu_rename_handler(p, 0, 0);
    rbuCreateVfs(p);

    /* Open the target, RBU and state databases */
    if( p->rc==SQLITE_OK ){
      char *pCsr = (char*)&p[1];
      int bRetry = 0;
      if( zTarget ){

    }
    if( rc==SQLITE_OK ) rc = sqlite3_exec(p->dbMain, "BEGIN IMMEDIATE", 0, 0,0);
  }

  p->rc = rc;
  return rc;
}

/*
** Default xRename callback for RBU.
*/
static int xDefaultRename(void *pArg, const char *zOld, const char *zNew){
  int rc = SQLITE_OK;
#if defined(_WIN32_WCE)
  {
    LPWSTR zWideOld;
    LPWSTR zWideNew;

    zWideOld = rbuWinUtf8ToUnicode(zOld);
    if( zWideOld ){
      zWideNew = rbuWinUtf8ToUnicode(zNew);
      if( zWideNew ){
        if( MoveFileW(zWideOld, zWideNew) ){
          rc = SQLITE_OK;
        }else{
          rc = SQLITE_IOERR;
        }
        sqlite3_free(zWideNew);
      }else{
        rc = SQLITE_IOERR_NOMEM;
      }
      sqlite3_free(zWideOld);
    }else{
      rc = SQLITE_IOERR_NOMEM;
    }
  }
#else
  rc = rename(zOld, zNew) ? SQLITE_IOERR : SQLITE_OK;
#endif
  return rc;
}

SQLITE_API void sqlite3rbu_rename_handler(
  sqlite3rbu *pRbu,
  void *pArg,
  int (*xRename)(void *pArg, const char *zOld, const char *zNew)
){
  if( xRename ){
    pRbu->xRename = xRename;
    pRbu->pRenameArg = pArg;
  }else{
    pRbu->xRename = xDefaultRename;
    pRbu->pRenameArg = 0;
  }
}

/**************************************************************************
** Beginning of RBU VFS shim methods. The VFS shim modifies the behaviour
** of a standard VFS in the following ways:
**
** 1. Whenever the first page of a main database file is read or
**    written, the value of the change-counter cookie is stored in

  switch( i ){
    case 0: {           /* pgno */
      sqlite3_result_int(ctx, pCsr->pgno);
      break;
    }
    case 1: {           /* data */
      DbPage *pDbPage = 0;
      if( pCsr->pgno==((PENDING_BYTE/pCsr->szPage)+1) ){
        /* The pending byte page. Assume it is zeroed out. Attempting to
        ** request this page from the page is an SQLITE_CORRUPT error. */
        sqlite3_result_zeroblob(ctx, pCsr->szPage);
      }else{
        rc = sqlite3PagerGet(pCsr->pPager, pCsr->pgno, (DbPage**)&pDbPage, 0);
        if( rc==SQLITE_OK ){
          sqlite3_result_blob(ctx, sqlite3PagerGetData(pDbPage), pCsr->szPage,
              SQLITE_TRANSIENT);
        }
        sqlite3PagerUnref(pDbPage);
      }
      break;
    }
    default: {          /* schema */
      sqlite3 *db = sqlite3_context_db_handle(ctx);
      sqlite3_result_text(ctx, db->aDb[pCsr->iDb].zDbSName, -1, SQLITE_STATIC);
      break;
    }
  }
  return rc;
}

static int dbpageRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
  DbpageCursor *pCsr = (DbpageCursor *)pCursor;
  *pRowid = pCsr->pgno;
  return SQLITE_OK;
}

  ){
    zErr = "bad page value";
    goto update_fail;
  }
  pPager = sqlite3BtreePager(pBt);
  rc = sqlite3PagerGet(pPager, pgno, (DbPage**)&pDbPage, 0);
  if( rc==SQLITE_OK ){
    const void *pData = sqlite3_value_blob(argv[3]);
    assert( pData!=0 || pTab->db->mallocFailed );
    if( pData
     && (rc = sqlite3PagerWrite(pDbPage))==SQLITE_OK
    ){
      memcpy(sqlite3PagerGetData(pDbPage), pData, szPage);


    }
  }
  sqlite3PagerUnref(pDbPage);
  return rc;

update_fail:
  sqlite3_free(pVtab->zErrMsg);

static void fts5SourceIdFunc(
  sqlite3_context *pCtx,          /* Function call context */
  int nArg,                       /* Number of args */
  sqlite3_value **apUnused        /* Function arguments */
){
  assert( nArg==0 );
  UNUSED_PARAM2(nArg, apUnused);
  sqlite3_result_text(pCtx, "fts5: 2022-11-07 19:40:20 55a19677d723147aeb2b4a86bbd01756ddeb2072cba72c3145ad32d335e203b0", -1, SQLITE_TRANSIENT);
}

/*
** Return true if zName is the extension on one of the shadow tables used
** by this module.
*/
static int fts5ShadowName(const char *zName){