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/*
** 2001 September 15
**
** 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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
*/
#ifndef SQLITEINT_H
#define SQLITEINT_H

/* Special Comments:
**
** Some comments have special meaning to the tools that measure test
** coverage:
**
**    NO_TEST                     - The branches on this line are not
**                                  measured by branch coverage.  This is
**                                  used on lines of code that actually
**                                  implement parts of coverage testing.
**
**    OPTIMIZATION-IF-TRUE        - This branch is allowed to always be false
**                                  and the correct answer is still obtained,
**                                  though perhaps more slowly.
**
**    OPTIMIZATION-IF-FALSE       - This branch is allowed to always be true
**                                  and the correct answer is still obtained,
**                                  though perhaps more slowly.
**
**    PREVENTS-HARMLESS-OVERREAD  - This branch prevents a buffer overread
**                                  that would be harmless and undetectable
**                                  if it did occur.
**
** In all cases, the special comment must be enclosed in the usual
** slash-asterisk...asterisk-slash comment marks, with no spaces between the
** asterisks and the comment text.
*/

/*
** Make sure the Tcl calling convention macro is defined.  This macro is
** only used by test code and Tcl integration code.
*/
#ifndef SQLITE_TCLAPI
#  define SQLITE_TCLAPI
#endif

/*
** Include the header file used to customize the compiler options for MSVC.
** This should be done first so that it can successfully prevent spurious
** compiler warnings due to subsequent content in this file and other files
** that are included by this file.
*/
#include "msvc.h"

/*
** Special setup for VxWorks
*/
#include "vxworks.h"

/*
** These #defines should enable >2GB file support on POSIX if the
** underlying operating system supports it.  If the OS lacks
** large file support, or if the OS is windows, these should be no-ops.
**
** Ticket #2739:  The _LARGEFILE_SOURCE macro must appear before any
** system #includes.  Hence, this block of code must be the very first
** code in all source files.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
** on a recent machine (ex: Red Hat 7.2) but you want your code to work
** on an older machine (ex: Red Hat 6.0).  If you compile on Red Hat 7.2
** without this option, LFS is enable.  But LFS does not exist in the kernel
** in Red Hat 6.0, so the code won't work.  Hence, for maximum binary
** portability you should omit LFS.
**
** The previous paragraph was written in 2005.  (This paragraph is written
** on 2008-11-28.) These days, all Linux kernels support large files, so
** you should probably leave LFS enabled.  But some embedded platforms might
** lack LFS in which case the SQLITE_DISABLE_LFS macro might still be useful.
**
** Similar is true for Mac OS X.  LFS is only supported on Mac OS X 9 and later.
*/
#ifndef SQLITE_DISABLE_LFS
# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

/* The GCC_VERSION and MSVC_VERSION macros are used to
** conditionally include optimizations for each of these compilers.  A
** value of 0 means that compiler is not being used.  The
** SQLITE_DISABLE_INTRINSIC macro means do not use any compiler-specific
** optimizations, and hence set all compiler macros to 0
**
** There was once also a CLANG_VERSION macro.  However, we learn that the
** version numbers in clang are for "marketing" only and are inconsistent
** and unreliable.  Fortunately, all versions of clang also recognize the
** gcc version numbers and have reasonable settings for gcc version numbers,
** so the GCC_VERSION macro will be set to a correct non-zero value even
** when compiling with clang.
*/
#if defined(__GNUC__) && !defined(SQLITE_DISABLE_INTRINSIC)
# define GCC_VERSION (__GNUC__*1000000+__GNUC_MINOR__*1000+__GNUC_PATCHLEVEL__)
#else
# define GCC_VERSION 0
#endif
#if defined(_MSC_VER) && !defined(SQLITE_DISABLE_INTRINSIC)
# define MSVC_VERSION _MSC_VER
#else
# define MSVC_VERSION 0
#endif

/*
** Some C99 functions in "math.h" are only present for MSVC when its version
** is associated with Visual Studio 2013 or higher.
*/
#ifndef SQLITE_HAVE_C99_MATH_FUNCS
# if MSVC_VERSION==0 || MSVC_VERSION>=1800
#  define SQLITE_HAVE_C99_MATH_FUNCS (1)
# else
#  define SQLITE_HAVE_C99_MATH_FUNCS (0)
# endif
#endif

/* Needed for various definitions... */
#if defined(__GNUC__) && !defined(_GNU_SOURCE)
# define _GNU_SOURCE
#endif

#if defined(__OpenBSD__) && !defined(_BSD_SOURCE)
# define _BSD_SOURCE
#endif

/*
** Macro to disable warnings about missing "break" at the end of a "case".
*/
#if defined(__has_attribute)
#  if __has_attribute(fallthrough)
#    define deliberate_fall_through __attribute__((fallthrough));
#  endif
#endif
#if !defined(deliberate_fall_through)
#  define deliberate_fall_through
#endif

/*
** For MinGW, check to see if we can include the header file containing its
** version information, among other things.  Normally, this internal MinGW
** header file would [only] be included automatically by other MinGW header
** files; however, the contained version information is now required by this
** header file to work around binary compatibility issues (see below) and
** this is the only known way to reliably obtain it.  This entire #if block
** would be completely unnecessary if there was any other way of detecting
** MinGW via their preprocessor (e.g. if they customized their GCC to define
** some MinGW-specific macros).  When compiling for MinGW, either the
** _HAVE_MINGW_H or _HAVE__MINGW_H (note the extra underscore) macro must be
** defined; otherwise, detection of conditions specific to MinGW will be
** disabled.
*/
#if defined(_HAVE_MINGW_H)
# include "mingw.h"
#elif defined(_HAVE__MINGW_H)
# include "_mingw.h"
#endif

/*
** For MinGW version 4.x (and higher), check to see if the _USE_32BIT_TIME_T
** define is required to maintain binary compatibility with the MSVC runtime
** library in use (e.g. for Windows XP).
*/
#if !defined(_USE_32BIT_TIME_T) && !defined(_USE_64BIT_TIME_T) && \
    defined(_WIN32) && !defined(_WIN64) && \
    defined(__MINGW_MAJOR_VERSION) && __MINGW_MAJOR_VERSION >= 4 && \
    defined(__MSVCRT__)
# define _USE_32BIT_TIME_T
#endif

/* Optionally #include a user-defined header, whereby compilation options
** may be set prior to where they take effect, but after platform setup.
** If SQLITE_CUSTOM_INCLUDE=? is defined, its value names the #include
** file.
*/
#ifdef SQLITE_CUSTOM_INCLUDE
# define INC_STRINGIFY_(f) #f
# define INC_STRINGIFY(f) INC_STRINGIFY_(f)
# include INC_STRINGIFY(SQLITE_CUSTOM_INCLUDE)
#endif

/* The public SQLite interface.  The _FILE_OFFSET_BITS macro must appear
** first in QNX.  Also, the _USE_32BIT_TIME_T macro must appear first for
** MinGW.
*/
#include "sqlite3.h"

/*
** Reuse the STATIC_LRU for mutex access to sqlite3_temp_directory.
*/
#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"

/* Disable nuisance warnings on Borland compilers */
#if defined(__BORLANDC__)
#pragma warn -rch /* unreachable code */
#pragma warn -ccc /* Condition is always true or false */
#pragma warn -aus /* Assigned value is never used */
#pragma warn -csu /* Comparing signed and unsigned */
#pragma warn -spa /* Suspicious pointer arithmetic */
#endif

/*
** A few places in the code require atomic load/store of aligned
** integer values.
*/
#ifndef __has_extension
# define __has_extension(x) 0     /* compatibility with non-clang compilers */
#endif
#if GCC_VERSION>=4007000 || __has_extension(c_atomic)
# define SQLITE_ATOMIC_INTRINSICS 1
# define AtomicLoad(PTR)       __atomic_load_n((PTR),__ATOMIC_RELAXED)
# define AtomicStore(PTR,VAL)  __atomic_store_n((PTR),(VAL),__ATOMIC_RELAXED)
#else
# define SQLITE_ATOMIC_INTRINSICS 0
# define AtomicLoad(PTR)       (*(PTR))
# define AtomicStore(PTR,VAL)  (*(PTR) = (VAL))
#endif

/*
** Include standard header files as necessary
*/
#include 
#ifdef HAVE_INTTYPES_H
#include 
#endif

/*
** The following macros are used to cast pointers to integers and
** integers to pointers.  The way you do this varies from one compiler
** to the next, so we have developed the following set of #if statements
** to generate appropriate macros for a wide range of compilers.
**
** The correct "ANSI" way to do this is to use the intptr_t type.
** Unfortunately, that typedef is not available on all compilers, or
** if it is available, it requires an #include of specific headers
** that vary from one machine to the next.
**
** Ticket #3860:  The llvm-gcc-4.2 compiler from Apple chokes on
** the ((void*)&((char*)0)[X]) construct.  But MSVC chokes on ((void*)(X)).
** So we have to define the macros in different ways depending on the
** compiler.
*/
#if defined(HAVE_STDINT_H)   /* Use this case if we have ANSI headers */
# define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
#elif defined(__PTRDIFF_TYPE__)  /* This case should work for GCC */
# define SQLITE_INT_TO_PTR(X)  ((void*)(__PTRDIFF_TYPE__)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(__PTRDIFF_TYPE__)(X))
#elif !defined(__GNUC__)       /* Works for compilers other than LLVM */
# define SQLITE_INT_TO_PTR(X)  ((void*)&((char*)0)[X])
# define SQLITE_PTR_TO_INT(X)  ((int)(((char*)X)-(char*)0))
#else                          /* Generates a warning - but it always works */
# define SQLITE_INT_TO_PTR(X)  ((void*)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(X))
#endif

/*
** Macros to hint to the compiler that a function should or should not be
** inlined.
*/
#if defined(__GNUC__)
#  define SQLITE_NOINLINE  __attribute__((noinline))
#  define SQLITE_INLINE    __attribute__((always_inline)) inline
#elif defined(_MSC_VER) && _MSC_VER>=1310
#  define SQLITE_NOINLINE  __declspec(noinline)
#  define SQLITE_INLINE    __forceinline
#else
#  define SQLITE_NOINLINE
#  define SQLITE_INLINE
#endif
#if defined(SQLITE_COVERAGE_TEST) || defined(__STRICT_ANSI__)
# undef SQLITE_INLINE
# define SQLITE_INLINE
#endif

/*
** Make sure that the compiler intrinsics we desire are enabled when
** compiling with an appropriate version of MSVC unless prevented by
** the SQLITE_DISABLE_INTRINSIC define.
*/
#if !defined(SQLITE_DISABLE_INTRINSIC)
#  if defined(_MSC_VER) && _MSC_VER>=1400
#    if !defined(_WIN32_WCE)
#      include 
#      pragma intrinsic(_byteswap_ushort)
#      pragma intrinsic(_byteswap_ulong)
#      pragma intrinsic(_byteswap_uint64)
#      pragma intrinsic(_ReadWriteBarrier)
#    else
#      include 
#    endif
#  endif
#endif

/*
** Enable SQLITE_USE_SEH by default on MSVC builds.  Only omit
** SEH support if the -DSQLITE_OMIT_SEH option is given.
*/
#if defined(_MSC_VER) && !defined(SQLITE_OMIT_SEH)
# define SQLITE_USE_SEH 1
#else
# undef SQLITE_USE_SEH
#endif

/*
** Enable SQLITE_DIRECT_OVERFLOW_READ, unless the build explicitly
** disables it using -DSQLITE_DIRECT_OVERFLOW_READ=0
*/
#if defined(SQLITE_DIRECT_OVERFLOW_READ) && SQLITE_DIRECT_OVERFLOW_READ+1==1
  /* Disable if -DSQLITE_DIRECT_OVERFLOW_READ=0 */
# undef SQLITE_DIRECT_OVERFLOW_READ
#else
  /* In all other cases, enable */
# define SQLITE_DIRECT_OVERFLOW_READ 1
#endif


/*
** The SQLITE_THREADSAFE macro must be defined as 0, 1, or 2.
** 0 means mutexes are permanently disable and the library is never
** threadsafe.  1 means the library is serialized which is the highest
** level of threadsafety.  2 means the library is multithreaded - multiple
** threads can use SQLite as long as no two threads try to use the same
** database connection at the same time.
**
** Older versions of SQLite used an optional THREADSAFE macro.
** We support that for legacy.
**
** To ensure that the correct value of "THREADSAFE" is reported when querying
** for compile-time options at runtime (e.g. "PRAGMA compile_options"), this
** logic is partially replicated in ctime.c. If it is updated here, it should
** also be updated there.
*/
#if !defined(SQLITE_THREADSAFE)
# if defined(THREADSAFE)
#   define SQLITE_THREADSAFE THREADSAFE
# else
#   define SQLITE_THREADSAFE 1 /* IMP: R-07272-22309 */
# endif
#endif

/*
** Powersafe overwrite is on by default.  But can be turned off using
** the -DSQLITE_POWERSAFE_OVERWRITE=0 command-line option.
*/
#ifndef SQLITE_POWERSAFE_OVERWRITE
# define SQLITE_POWERSAFE_OVERWRITE 1
#endif

/*
** EVIDENCE-OF: R-25715-37072 Memory allocation statistics are enabled by
** default unless SQLite is compiled with SQLITE_DEFAULT_MEMSTATUS=0 in
** which case memory allocation statistics are disabled by default.
*/
#if !defined(SQLITE_DEFAULT_MEMSTATUS)
# define SQLITE_DEFAULT_MEMSTATUS 1
#endif

/*
** Exactly one of the following macros must be defined in order to
** specify which memory allocation subsystem to use.
**
**     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
**     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
**     SQLITE_ZERO_MALLOC            // Use a stub allocator that always fails
**     SQLITE_MEMDEBUG               // Debugging version of system malloc()
**
** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
** assert() macro is enabled, each call into the Win32 native heap subsystem
** will cause HeapValidate to be called.  If heap validation should fail, an
** assertion will be triggered.
**
** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
** the default.
*/
#if defined(SQLITE_SYSTEM_MALLOC) \
  + defined(SQLITE_WIN32_MALLOC) \
  + defined(SQLITE_ZERO_MALLOC) \
  + defined(SQLITE_MEMDEBUG)>1
# error "Two or more of the following compile-time configuration options\
 are defined but at most one is allowed:\
 SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG,\
 SQLITE_ZERO_MALLOC"
#endif
#if defined(SQLITE_SYSTEM_MALLOC) \
  + defined(SQLITE_WIN32_MALLOC) \
  + defined(SQLITE_ZERO_MALLOC) \
  + defined(SQLITE_MEMDEBUG)==0
# define SQLITE_SYSTEM_MALLOC 1
#endif

/*
** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
** sizes of memory allocations below this value where possible.
*/
#if !defined(SQLITE_MALLOC_SOFT_LIMIT)
# define SQLITE_MALLOC_SOFT_LIMIT 1024
#endif

/*
** We need to define _XOPEN_SOURCE as follows in order to enable
** recursive mutexes on most Unix systems and fchmod() on OpenBSD.
** But _XOPEN_SOURCE define causes problems for Mac OS X, so omit
** it.
*/
#if !defined(_XOPEN_SOURCE) && !defined(__DARWIN__) && !defined(__APPLE__)
#  define _XOPEN_SOURCE 600
#endif

/*
** NDEBUG and SQLITE_DEBUG are opposites.  It should always be true that
** defined(NDEBUG)==!defined(SQLITE_DEBUG).  If this is not currently true,
** make it true by defining or undefining NDEBUG.
**
** Setting NDEBUG makes the code smaller and faster by disabling the
** assert() statements in the code.  So we want the default action
** to be for NDEBUG to be set and NDEBUG to be undefined only if SQLITE_DEBUG
** is set.  Thus NDEBUG becomes an opt-in rather than an opt-out
** feature.
*/
#if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
# define NDEBUG 1
#endif
#if defined(NDEBUG) && defined(SQLITE_DEBUG)
# undef NDEBUG
#endif

/*
** Enable SQLITE_ENABLE_EXPLAIN_COMMENTS if SQLITE_DEBUG is turned on.
*/
#if !defined(SQLITE_ENABLE_EXPLAIN_COMMENTS) && defined(SQLITE_DEBUG)
# define SQLITE_ENABLE_EXPLAIN_COMMENTS 1
#endif

/*
** The testcase() macro is used to aid in coverage testing.  When
** doing coverage testing, the condition inside the argument to
** testcase() must be evaluated both true and false in order to
** get full branch coverage.  The testcase() macro is inserted
** to help ensure adequate test coverage in places where simple
** condition/decision coverage is inadequate.  For example, testcase()
** can be used to make sure boundary values are tested.  For
** bitmask tests, testcase() can be used to make sure each bit
** is significant and used at least once.  On switch statements
** where multiple cases go to the same block of code, testcase()
** can insure that all cases are evaluated.
*/
#if defined(SQLITE_COVERAGE_TEST) || defined(SQLITE_DEBUG)
# ifndef SQLITE_AMALGAMATION
    extern unsigned int sqlite3CoverageCounter;
# endif
# define testcase(X)  if( X ){ sqlite3CoverageCounter += (unsigned)__LINE__; }
#else
# define testcase(X)
#endif

/*
** The TESTONLY macro is used to enclose variable declarations or
** other bits of code that are needed to support the arguments
** within testcase() and assert() macros.
*/
#if !defined(NDEBUG) || defined(SQLITE_COVERAGE_TEST)
# define TESTONLY(X)  X
#else
# define TESTONLY(X)
#endif

/*
** Sometimes we need a small amount of code such as a variable initialization
** to setup for a later assert() statement.  We do not want this code to
** appear when assert() is disabled.  The following macro is therefore
** used to contain that setup code.  The "VVA" acronym stands for
** "Verification, Validation, and Accreditation".  In other words, the
** code within VVA_ONLY() will only run during verification processes.
*/
#ifndef NDEBUG
# define VVA_ONLY(X)  X
#else
# define VVA_ONLY(X)
#endif

/*
** Disable ALWAYS() and NEVER() (make them pass-throughs) for coverage
** and mutation testing
*/
#if defined(SQLITE_COVERAGE_TEST) || defined(SQLITE_MUTATION_TEST)
# define SQLITE_OMIT_AUXILIARY_SAFETY_CHECKS  1
#endif

/*
** The ALWAYS and NEVER macros surround boolean expressions which
** are intended to always be true or false, respectively.  Such
** expressions could be omitted from the code completely.  But they
** are included in a few cases in order to enhance the resilience
** of SQLite to unexpected behavior - to make the code "self-healing"
** or "ductile" rather than being "brittle" and crashing at the first
** hint of unplanned behavior.
**
** In other words, ALWAYS and NEVER are added for defensive code.
**
** When doing coverage testing ALWAYS and NEVER are hard-coded to
** be true and false so that the unreachable code they specify will
** not be counted as untested code.
*/
#if defined(SQLITE_OMIT_AUXILIARY_SAFETY_CHECKS)
# define ALWAYS(X)      (1)
# define NEVER(X)       (0)
#elif !defined(NDEBUG)
# define ALWAYS(X)      ((X)?1:(assert(0),0))
# define NEVER(X)       ((X)?(assert(0),1):0)
#else
# define ALWAYS(X)      (X)
# define NEVER(X)       (X)
#endif

/*
** Some conditionals are optimizations only.  In other words, if the
** conditionals are replaced with a constant 1 (true) or 0 (false) then
** the correct answer is still obtained, though perhaps not as quickly.
**
** The following macros mark these optimizations conditionals.
*/
#if defined(SQLITE_MUTATION_TEST)
# define OK_IF_ALWAYS_TRUE(X)  (1)
# define OK_IF_ALWAYS_FALSE(X) (0)
#else
# define OK_IF_ALWAYS_TRUE(X)  (X)
# define OK_IF_ALWAYS_FALSE(X) (X)
#endif

/*
** Some malloc failures are only possible if SQLITE_TEST_REALLOC_STRESS is
** defined.  We need to defend against those failures when testing with
** SQLITE_TEST_REALLOC_STRESS, but we don't want the unreachable branches
** during a normal build.  The following macro can be used to disable tests
** that are always false except when SQLITE_TEST_REALLOC_STRESS is set.
*/
#if defined(SQLITE_TEST_REALLOC_STRESS)
# define ONLY_IF_REALLOC_STRESS(X)  (X)
#elif !defined(NDEBUG)
# define ONLY_IF_REALLOC_STRESS(X)  ((X)?(assert(0),1):0)
#else
# define ONLY_IF_REALLOC_STRESS(X)  (0)
#endif

/*
** Declarations used for tracing the operating system interfaces.
*/
#if defined(SQLITE_FORCE_OS_TRACE) || defined(SQLITE_TEST) || \
    (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
  extern int sqlite3OSTrace;
# define OSTRACE(X)          if( sqlite3OSTrace ) sqlite3DebugPrintf X
# define SQLITE_HAVE_OS_TRACE
#else
# define OSTRACE(X)
# undef  SQLITE_HAVE_OS_TRACE
#endif

/*
** Is the sqlite3ErrName() function needed in the build?  Currently,
** it is needed by "mutex_w32.c" (when debugging), "os_win.c" (when
** OSTRACE is enabled), and by several "test*.c" files (which are
** compiled using SQLITE_TEST).
*/
#if defined(SQLITE_HAVE_OS_TRACE) || defined(SQLITE_TEST) || \
    (defined(SQLITE_DEBUG) && SQLITE_OS_WIN)
# define SQLITE_NEED_ERR_NAME
#else
# undef  SQLITE_NEED_ERR_NAME
#endif

/*
** SQLITE_ENABLE_EXPLAIN_COMMENTS is incompatible with SQLITE_OMIT_EXPLAIN
*/
#ifdef SQLITE_OMIT_EXPLAIN
# undef SQLITE_ENABLE_EXPLAIN_COMMENTS
#endif

/*
** SQLITE_OMIT_VIRTUALTABLE implies SQLITE_OMIT_ALTERTABLE
*/
#if defined(SQLITE_OMIT_VIRTUALTABLE) && !defined(SQLITE_OMIT_ALTERTABLE)
# define SQLITE_OMIT_ALTERTABLE
#endif

#define SQLITE_DIGIT_SEPARATOR '_'

/*
** Return true (non-zero) if the input is an integer that is too large
** to fit in 32-bits.  This macro is used inside of various testcase()
** macros to verify that we have tested SQLite for large-file support.
*/
#define IS_BIG_INT(X)  (((X)&~(i64)0xffffffff)!=0)

/*
** The macro unlikely() is a hint that surrounds a boolean
** expression that is usually false.  Macro likely() surrounds
** a boolean expression that is usually true.  These hints could,
** in theory, be used by the compiler to generate better code, but
** currently they are just comments for human readers.
*/
#define likely(X)    (X)
#define unlikely(X)  (X)

#include "hash.h"
#include "parse.h"
#include 
#include 
#include 
#include 
#include 
#include 

/*
** Use a macro to replace memcpy() if compiled with SQLITE_INLINE_MEMCPY.
** This allows better measurements of where memcpy() is used when running
** cachegrind.  But this macro version of memcpy() is very slow so it
** should not be used in production.  This is a performance measurement
** hack only.
*/
#ifdef SQLITE_INLINE_MEMCPY
# define memcpy(D,S,N) {char*xxd=(char*)(D);const char*xxs=(const char*)(S);\
                        int xxn=(N);while(xxn-->0)*(xxd++)=*(xxs++);}
#endif

/*
** If compiling for a processor that lacks floating point support,
** substitute integer for floating-point
*/
#ifdef SQLITE_OMIT_FLOATING_POINT
# define double sqlite_int64
# define float sqlite_int64
# define fabs(X) ((X)dbOptFlags&(mask))!=0)
#define OptimizationEnabled(db, mask)   (((db)->dbOptFlags&(mask))==0)

/*
** Return true if it OK to factor constant expressions into the initialization
** code. The argument is a Parse object for the code generator.
*/
#define ConstFactorOk(P) ((P)->okConstFactor)

/* Possible values for the sqlite3.eOpenState field.
** The numbers are randomly selected such that a minimum of three bits must
** change to convert any number to another or to zero
*/
#define SQLITE_STATE_OPEN     0x76  /* Database is open */
#define SQLITE_STATE_CLOSED   0xce  /* Database is closed */
#define SQLITE_STATE_SICK     0xba  /* Error and awaiting close */
#define SQLITE_STATE_BUSY     0x6d  /* Database currently in use */
#define SQLITE_STATE_ERROR    0xd5  /* An SQLITE_MISUSE error occurred */
#define SQLITE_STATE_ZOMBIE   0xa7  /* Close with last statement close */

/*
** Each SQL function is defined by an instance of the following
** structure.  For global built-in functions (ex: substr(), max(), count())
** a pointer to this structure is held in the sqlite3BuiltinFunctions object.
** For per-connection application-defined functions, a pointer to this
** structure is held in the db->aHash hash table.
**
** The u.pHash field is used by the global built-ins.  The u.pDestructor
** field is used by per-connection app-def functions.
*/
struct FuncDef {
  i16 nArg;            /* Number of arguments.  -1 means unlimited */
  u32 funcFlags;       /* Some combination of SQLITE_FUNC_* */
  void *pUserData;     /* User data parameter */
  FuncDef *pNext;      /* Next function with same name */
  void (*xSFunc)(sqlite3_context*,int,sqlite3_value**); /* func or agg-step */
  void (*xFinalize)(sqlite3_context*);                  /* Agg finalizer */
  void (*xValue)(sqlite3_context*);                     /* Current agg value */
  void (*xInverse)(sqlite3_context*,int,sqlite3_value**); /* inverse agg-step */
  const char *zName;   /* SQL name of the function. */
  union {
    FuncDef *pHash;      /* Next with a different name but the same hash */
    FuncDestructor *pDestructor;   /* Reference counted destructor function */
  } u; /* pHash if SQLITE_FUNC_BUILTIN, pDestructor otherwise */
};

/*
** This structure encapsulates a user-function destructor callback (as
** configured using create_function_v2()) and a reference counter. When
** create_function_v2() is called to create a function with a destructor,
** a single object of this type is allocated. FuncDestructor.nRef is set to
** the number of FuncDef objects created (either 1 or 3, depending on whether
** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
** member of each of the new FuncDef objects is set to point to the allocated
** FuncDestructor.
**
** Thereafter, when one of the FuncDef objects is deleted, the reference
** count on this object is decremented. When it reaches 0, the destructor
** is invoked and the FuncDestructor structure freed.
*/
struct FuncDestructor {
  int nRef;
  void (*xDestroy)(void *);
  void *pUserData;
};

/*
** Possible values for FuncDef.flags.  Note that the _LENGTH and _TYPEOF
** values must correspond to OPFLAG_LENGTHARG and OPFLAG_TYPEOFARG.  And
** SQLITE_FUNC_CONSTANT must be the same as SQLITE_DETERMINISTIC.  There
** are assert() statements in the code to verify this.
**
** Value constraints (enforced via assert()):
**     SQLITE_FUNC_MINMAX      ==  NC_MinMaxAgg      == SF_MinMaxAgg
**     SQLITE_FUNC_ANYORDER    ==  NC_OrderAgg       == SF_OrderByReqd
**     SQLITE_FUNC_LENGTH      ==  OPFLAG_LENGTHARG
**     SQLITE_FUNC_TYPEOF      ==  OPFLAG_TYPEOFARG
**     SQLITE_FUNC_BYTELEN     ==  OPFLAG_BYTELENARG
**     SQLITE_FUNC_CONSTANT    ==  SQLITE_DETERMINISTIC from the API
**     SQLITE_FUNC_DIRECT      ==  SQLITE_DIRECTONLY from the API
**     SQLITE_FUNC_UNSAFE      ==  SQLITE_INNOCUOUS  -- opposite meanings!!!
**     SQLITE_FUNC_ENCMASK   depends on SQLITE_UTF* macros in the API
**
** Note that even though SQLITE_FUNC_UNSAFE and SQLITE_INNOCUOUS have the
** same bit value, their meanings are inverted.  SQLITE_FUNC_UNSAFE is
** used internally and if set means that the function has side effects.
** SQLITE_INNOCUOUS is used by application code and means "not unsafe".
** See multiple instances of tag-20230109-1.
*/
#define SQLITE_FUNC_ENCMASK  0x0003 /* SQLITE_UTF8, SQLITE_UTF16BE or UTF16LE */
#define SQLITE_FUNC_LIKE     0x0004 /* Candidate for the LIKE optimization */
#define SQLITE_FUNC_CASE     0x0008 /* Case-sensitive LIKE-type function */
#define SQLITE_FUNC_EPHEM    0x0010 /* Ephemeral.  Delete with VDBE */
#define SQLITE_FUNC_NEEDCOLL 0x0020 /* sqlite3GetFuncCollSeq() might be called*/
#define SQLITE_FUNC_LENGTH   0x0040 /* Built-in length() function */
#define SQLITE_FUNC_TYPEOF   0x0080 /* Built-in typeof() function */
#define SQLITE_FUNC_BYTELEN  0x00c0 /* Built-in octet_length() function */
#define SQLITE_FUNC_COUNT    0x0100 /* Built-in count(*) aggregate */
/*                           0x0200 -- available for reuse */
#define SQLITE_FUNC_UNLIKELY 0x0400 /* Built-in unlikely() function */
#define SQLITE_FUNC_CONSTANT 0x0800 /* Constant inputs give a constant output */
#define SQLITE_FUNC_MINMAX   0x1000 /* True for min() and max() aggregates */
#define SQLITE_FUNC_SLOCHNG  0x2000 /* "Slow Change". Value constant during a
                                    ** single query - might change over time */
#define SQLITE_FUNC_TEST     0x4000 /* Built-in testing functions */
#define SQLITE_FUNC_RUNONLY  0x8000 /* Cannot be used by valueFromFunction */
#define SQLITE_FUNC_WINDOW   0x00010000 /* Built-in window-only function */
#define SQLITE_FUNC_INTERNAL 0x00040000 /* For use by NestedParse() only */
#define SQLITE_FUNC_DIRECT   0x00080000 /* Not for use in TRIGGERs or VIEWs */
/* SQLITE_SUBTYPE            0x00100000 // Consumer of subtypes */
#define SQLITE_FUNC_UNSAFE   0x00200000 /* Function has side effects */
#define SQLITE_FUNC_INLINE   0x00400000 /* Functions implemented in-line */
#define SQLITE_FUNC_BUILTIN  0x00800000 /* This is a built-in function */
/*  SQLITE_RESULT_SUBTYPE    0x01000000 // Generator of subtypes */
#define SQLITE_FUNC_ANYORDER 0x08000000 /* count/min/max aggregate */

/* Identifier numbers for each in-line function */
#define INLINEFUNC_coalesce             0
#define INLINEFUNC_implies_nonnull_row  1
#define INLINEFUNC_expr_implies_expr    2
#define INLINEFUNC_expr_compare         3
#define INLINEFUNC_affinity             4
#define INLINEFUNC_iif                  5
#define INLINEFUNC_sqlite_offset        6
#define INLINEFUNC_unlikely            99  /* Default case */

/*
** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
** used to create the initializers for the FuncDef structures.
**
**   FUNCTION(zName, nArg, iArg, bNC, xFunc)
**     Used to create a scalar function definition of a function zName
**     implemented by C function xFunc that accepts nArg arguments. The
**     value passed as iArg is cast to a (void*) and made available
**     as the user-data (sqlite3_user_data()) for the function. If
**     argument bNC is true, then the SQLITE_FUNC_NEEDCOLL flag is set.
**
**   VFUNCTION(zName, nArg, iArg, bNC, xFunc)
**     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag.
**
**   SFUNCTION(zName, nArg, iArg, bNC, xFunc)
**     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
**     adds the SQLITE_DIRECTONLY flag.
**
**   INLINE_FUNC(zName, nArg, iFuncId, mFlags)
**     zName is the name of a function that is implemented by in-line
**     byte code rather than by the usual callbacks. The iFuncId
**     parameter determines the function id.  The mFlags parameter is
**     optional SQLITE_FUNC_ flags for this function.
**
**   TEST_FUNC(zName, nArg, iFuncId, mFlags)
**     zName is the name of a test-only function implemented by in-line
**     byte code rather than by the usual callbacks. The iFuncId
**     parameter determines the function id.  The mFlags parameter is
**     optional SQLITE_FUNC_ flags for this function.
**
**   DFUNCTION(zName, nArg, iArg, bNC, xFunc)
**     Like FUNCTION except it omits the SQLITE_FUNC_CONSTANT flag and
**     adds the SQLITE_FUNC_SLOCHNG flag.  Used for date & time functions
**     and functions like sqlite_version() that can change, but not during
**     a single query.  The iArg is ignored.  The user-data is always set
**     to a NULL pointer.  The bNC parameter is not used.
**
**   MFUNCTION(zName, nArg, xPtr, xFunc)
**     For math-library functions.  xPtr is an arbitrary pointer.
**
**   PURE_DATE(zName, nArg, iArg, bNC, xFunc)
**     Used for "pure" date/time functions, this macro is like DFUNCTION
**     except that it does set the SQLITE_FUNC_CONSTANT flags.  iArg is
**     ignored and the user-data for these functions is set to an
**     arbitrary non-NULL pointer.  The bNC parameter is not used.
**
**   AGGREGATE(zName, nArg, iArg, bNC, xStep, xFinal)
**     Used to create an aggregate function definition implemented by
**     the C functions xStep and xFinal. The first four parameters
**     are interpreted in the same way as the first 4 parameters to
**     FUNCTION().
**
**   WAGGREGATE(zName, nArg, iArg, xStep, xFinal, xValue, xInverse)
**     Used to create an aggregate function definition implemented by
**     the C functions xStep and xFinal. The first four parameters
**     are interpreted in the same way as the first 4 parameters to
**     FUNCTION().
**
**   LIKEFUNC(zName, nArg, pArg, flags)
**     Used to create a scalar function definition of a function zName
**     that accepts nArg arguments and is implemented by a call to C
**     function likeFunc. Argument pArg is cast to a (void *) and made
**     available as the function user-data (sqlite3_user_data()). The
**     FuncDef.flags variable is set to the value passed as the flags
**     parameter.
*/
#define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|\
   SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define SFUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_UTF8|SQLITE_DIRECTONLY|SQLITE_FUNC_UNSAFE, \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define MFUNCTION(zName, nArg, xPtr, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_CONSTANT|SQLITE_UTF8, \
   xPtr, 0, xFunc, 0, 0, 0, #zName, {0} }
#define JFUNCTION(zName, nArg, bUseCache, bWS, bRS, bJsonB, iArg, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_DETERMINISTIC|SQLITE_FUNC_CONSTANT|\
   SQLITE_UTF8|((bUseCache)*SQLITE_FUNC_RUNONLY)|\
   ((bRS)*SQLITE_SUBTYPE)|((bWS)*SQLITE_RESULT_SUBTYPE), \
   SQLITE_INT_TO_PTR(iArg|((bJsonB)*JSON_BLOB)),0,xFunc,0, 0, 0, #zName, {0} }
#define INLINE_FUNC(zName, nArg, iArg, mFlags) \
  {nArg, SQLITE_FUNC_BUILTIN|\
   SQLITE_UTF8|SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
   SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
#define TEST_FUNC(zName, nArg, iArg, mFlags) \
  {nArg, SQLITE_FUNC_BUILTIN|\
         SQLITE_UTF8|SQLITE_FUNC_INTERNAL|SQLITE_FUNC_TEST| \
         SQLITE_FUNC_INLINE|SQLITE_FUNC_CONSTANT|(mFlags), \
   SQLITE_INT_TO_PTR(iArg), 0, noopFunc, 0, 0, 0, #zName, {0} }
#define DFUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_SLOCHNG|SQLITE_UTF8, \
   0, 0, xFunc, 0, 0, 0, #zName, {0} }
#define PURE_DATE(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|\
         SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|SQLITE_FUNC_CONSTANT, \
   (void*)&sqlite3Config, 0, xFunc, 0, 0, 0, #zName, {0} }
#define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
  {nArg, SQLITE_FUNC_BUILTIN|\
   SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, 0, #zName, {0} }
#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|\
   SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   pArg, 0, xFunc, 0, 0, 0, #zName, {0} }
#define LIKEFUNC(zName, nArg, arg, flags) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
   (void *)arg, 0, likeFunc, 0, 0, 0, #zName, {0} }
#define WAGGREGATE(zName, nArg, arg, nc, xStep, xFinal, xValue, xInverse, f) \
  {nArg, SQLITE_FUNC_BUILTIN|SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|f, \
   SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,xValue,xInverse,#zName, {0}}
#define INTERNAL_FUNCTION(zName, nArg, xFunc) \
  {nArg, SQLITE_FUNC_BUILTIN|\
   SQLITE_FUNC_INTERNAL|SQLITE_UTF8|SQLITE_FUNC_CONSTANT, \
   0, 0, xFunc, 0, 0, 0, #zName, {0} }


/*
** All current savepoints are stored in a linked list starting at
** sqlite3.pSavepoint. The first element in the list is the most recently
** opened savepoint. Savepoints are added to the list by the vdbe
** OP_Savepoint instruction.
*/
struct Savepoint {
  char *zName;                        /* Savepoint name (nul-terminated) */
  i64 nDeferredCons;                  /* Number of deferred fk violations */
  i64 nDeferredImmCons;               /* Number of deferred imm fk. */
  Savepoint *pNext;                   /* Parent savepoint (if any) */
};

/*
** The following are used as the second parameter to sqlite3Savepoint(),
** and as the P1 argument to the OP_Savepoint instruction.
*/
#define SAVEPOINT_BEGIN      0
#define SAVEPOINT_RELEASE    1
#define SAVEPOINT_ROLLBACK   2


/*
** Each SQLite module (virtual table definition) is defined by an
** instance of the following structure, stored in the sqlite3.aModule
** hash table.
*/
struct Module {
  const sqlite3_module *pModule;       /* Callback pointers */
  const char *zName;                   /* Name passed to create_module() */
  int nRefModule;                      /* Number of pointers to this object */
  void *pAux;                          /* pAux passed to create_module() */
  void (*xDestroy)(void *);            /* Module destructor function */
  Table *pEpoTab;                      /* Eponymous table for this module */
};

/*
** Information about each column of an SQL table is held in an instance
** of the Column structure, in the Table.aCol[] array.
**
** Definitions:
**
**   "table column index"     This is the index of the column in the
**                            Table.aCol[] array, and also the index of
**                            the column in the original CREATE TABLE stmt.
**
**   "storage column index"   This is the index of the column in the
**                            record BLOB generated by the OP_MakeRecord
**                            opcode.  The storage column index is less than
**                            or equal to the table column index.  It is
**                            equal if and only if there are no VIRTUAL
**                            columns to the left.
**
** Notes on zCnName:
** The zCnName field stores the name of the column, the datatype of the
** column, and the collating sequence for the column, in that order, all in
** a single allocation.  Each string is 0x00 terminated.  The datatype
** is only included if the COLFLAG_HASTYPE bit of colFlags is set and the
** collating sequence name is only included if the COLFLAG_HASCOLL bit is
** set.
*/
struct Column {
  char *zCnName;        /* Name of this column */
  unsigned notNull :4;  /* An OE_ code for handling a NOT NULL constraint */
  unsigned eCType :4;   /* One of the standard types */
  char affinity;        /* One of the SQLITE_AFF_... values */
  u8 szEst;             /* Est size of value in this column. sizeof(INT)==1 */
  u8 hName;             /* Column name hash for faster lookup */
  u16 iDflt;            /* 1-based index of DEFAULT.  0 means "none" */
  u16 colFlags;         /* Boolean properties.  See COLFLAG_ defines below */
};

/* Allowed values for Column.eCType.
**
** Values must match entries in the global constant arrays
** sqlite3StdTypeLen[] and sqlite3StdType[].  Each value is one more
** than the offset into these arrays for the corresponding name.
** Adjust the SQLITE_N_STDTYPE value if adding or removing entries.
*/
#define COLTYPE_CUSTOM      0   /* Type appended to zName */
#define COLTYPE_ANY         1
#define COLTYPE_BLOB        2
#define COLTYPE_INT         3
#define COLTYPE_INTEGER     4
#define COLTYPE_REAL        5
#define COLTYPE_TEXT        6
#define SQLITE_N_STDTYPE    6  /* Number of standard types */

/* Allowed values for Column.colFlags.
**
** Constraints:
**         TF_HasVirtual == COLFLAG_VIRTUAL
**         TF_HasStored  == COLFLAG_STORED
**         TF_HasHidden  == COLFLAG_HIDDEN
*/
#define COLFLAG_PRIMKEY   0x0001   /* Column is part of the primary key */
#define COLFLAG_HIDDEN    0x0002   /* A hidden column in a virtual table */
#define COLFLAG_HASTYPE   0x0004   /* Type name follows column name */
#define COLFLAG_UNIQUE    0x0008   /* Column def contains "UNIQUE" or "PK" */
#define COLFLAG_SORTERREF 0x0010   /* Use sorter-refs with this column */
#define COLFLAG_VIRTUAL   0x0020   /* GENERATED ALWAYS AS ... VIRTUAL */
#define COLFLAG_STORED    0x0040   /* GENERATED ALWAYS AS ... STORED */
#define COLFLAG_NOTAVAIL  0x0080   /* STORED column not yet calculated */
#define COLFLAG_BUSY      0x0100   /* Blocks recursion on GENERATED columns */
#define COLFLAG_HASCOLL   0x0200   /* Has collating sequence name in zCnName */
#define COLFLAG_NOEXPAND  0x0400   /* Omit this column when expanding "*" */
#define COLFLAG_GENERATED 0x0060   /* Combo: _STORED, _VIRTUAL */
#define COLFLAG_NOINSERT  0x0062   /* Combo: _HIDDEN, _STORED, _VIRTUAL */

/*
** A "Collating Sequence" is defined by an instance of the following
** structure. Conceptually, a collating sequence consists of a name and
** a comparison routine that defines the order of that sequence.
**
** If CollSeq.xCmp is NULL, it means that the
** collating sequence is undefined.  Indices built on an undefined
** collating sequence may not be read or written.
*/
struct CollSeq {
  char *zName;          /* Name of the collating sequence, UTF-8 encoded */
  u8 enc;               /* Text encoding handled by xCmp() */
  void *pUser;          /* First argument to xCmp() */
  int (*xCmp)(void*,int, const void*, int, const void*);
  void (*xDel)(void*);  /* Destructor for pUser */
};

/*
** A sort order can be either ASC or DESC.
*/
#define SQLITE_SO_ASC       0  /* Sort in ascending order */
#define SQLITE_SO_DESC      1  /* Sort in ascending order */
#define SQLITE_SO_UNDEFINED -1 /* No sort order specified */

/*
** Column affinity types.
**
** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
** 't' for SQLITE_AFF_TEXT.  But we can save a little space and improve
** the speed a little by numbering the values consecutively.
**
** But rather than start with 0 or 1, we begin with 'A'.  That way,
** when multiple affinity types are concatenated into a string and
** used as the P4 operand, they will be more readable.
**
** Note also that the numeric types are grouped together so that testing
** for a numeric type is a single comparison.  And the BLOB type is first.
*/
#define SQLITE_AFF_NONE     0x40  /* '@' */
#define SQLITE_AFF_BLOB     0x41  /* 'A' */
#define SQLITE_AFF_TEXT     0x42  /* 'B' */
#define SQLITE_AFF_NUMERIC  0x43  /* 'C' */
#define SQLITE_AFF_INTEGER  0x44  /* 'D' */
#define SQLITE_AFF_REAL     0x45  /* 'E' */
#define SQLITE_AFF_FLEXNUM  0x46  /* 'F' */
#define SQLITE_AFF_DEFER    0x58  /* 'X'  - defer computation until later */

#define sqlite3IsNumericAffinity(X)  ((X)>=SQLITE_AFF_NUMERIC)

/*
** The SQLITE_AFF_MASK values masks off the significant bits of an
** affinity value.
*/
#define SQLITE_AFF_MASK     0x47

/*
** Additional bit values that can be ORed with an affinity without
** changing the affinity.
**
** The SQLITE_NOTNULL flag is a combination of NULLEQ and JUMPIFNULL.
** It causes an assert() to fire if either operand to a comparison
** operator is NULL.  It is added to certain comparison operators to
** prove that the operands are always NOT NULL.
*/
#define SQLITE_JUMPIFNULL   0x10  /* jumps if either operand is NULL */
#define SQLITE_NULLEQ       0x80  /* NULL=NULL */
#define SQLITE_NOTNULL      0x90  /* Assert that operands are never NULL */

/*
** An object of this type is created for each virtual table present in
** the database schema.
**
** If the database schema is shared, then there is one instance of this
** structure for each database connection (sqlite3*) that uses the shared
** schema. This is because each database connection requires its own unique
** instance of the sqlite3_vtab* handle used to access the virtual table
** implementation. sqlite3_vtab* handles can not be shared between
** database connections, even when the rest of the in-memory database
** schema is shared, as the implementation often stores the database
** connection handle passed to it via the xConnect() or xCreate() method
** during initialization internally. This database connection handle may
** then be used by the virtual table implementation to access real tables
** within the database. So that they appear as part of the callers
** transaction, these accesses need to be made via the same database
** connection as that used to execute SQL operations on the virtual table.
**
** All VTable objects that correspond to a single table in a shared
** database schema are initially stored in a linked-list pointed to by
** the Table.pVTable member variable of the corresponding Table object.
** When an sqlite3_prepare() operation is required to access the virtual
** table, it searches the list for the VTable that corresponds to the
** database connection doing the preparing so as to use the correct
** sqlite3_vtab* handle in the compiled query.
**
** When an in-memory Table object is deleted (for example when the
** schema is being reloaded for some reason), the VTable objects are not
** deleted and the sqlite3_vtab* handles are not xDisconnect()ed
** immediately. Instead, they are moved from the Table.pVTable list to
** another linked list headed by the sqlite3.pDisconnect member of the
** corresponding sqlite3 structure. They are then deleted/xDisconnected
** next time a statement is prepared using said sqlite3*. This is done
** to avoid deadlock issues involving multiple sqlite3.mutex mutexes.
** Refer to comments above function sqlite3VtabUnlockList() for an
** explanation as to why it is safe to add an entry to an sqlite3.pDisconnect
** list without holding the corresponding sqlite3.mutex mutex.
**
** The memory for objects of this type is always allocated by
** sqlite3DbMalloc(), using the connection handle stored in VTable.db as
** the first argument.
*/
struct VTable {
  sqlite3 *db;              /* Database connection associated with this table */
  Module *pMod;             /* Pointer to module implementation */
  sqlite3_vtab *pVtab;      /* Pointer to vtab instance */
  int nRef;                 /* Number of pointers to this structure */
  u8 bConstraint;           /* True if constraints are supported */
  u8 bAllSchemas;           /* True if might use any attached schema */
  u8 eVtabRisk;             /* Riskiness of allowing hacker access */
  int iSavepoint;           /* Depth of the SAVEPOINT stack */
  VTable *pNext;            /* Next in linked list (see above) */
};

/* Allowed values for VTable.eVtabRisk
*/
#define SQLITE_VTABRISK_Low          0
#define SQLITE_VTABRISK_Normal       1
#define SQLITE_VTABRISK_High         2

/*
** The schema for each SQL table, virtual table, and view is represented
** in memory by an instance of the following structure.
*/
struct Table {
  char *zName;         /* Name of the table or view */
  Column *aCol;        /* Information about each column */
  Index *pIndex;       /* List of SQL indexes on this table. */
  char *zColAff;       /* String defining the affinity of each column */
  ExprList *pCheck;    /* All CHECK constraints */
                       /*   ... also used as column name list in a VIEW */
  Pgno tnum;           /* Root BTree page for this table */
  u32 nTabRef;         /* Number of pointers to this Table */
  u32 tabFlags;        /* Mask of TF_* values */
  i16 iPKey;           /* If not negative, use aCol[iPKey] as the rowid */
  i16 nCol;            /* Number of columns in this table */
  i16 nNVCol;          /* Number of columns that are not VIRTUAL */
  LogEst nRowLogEst;   /* Estimated rows in table - from sqlite_stat1 table */
  LogEst szTabRow;     /* Estimated size of each table row in bytes */
#ifdef SQLITE_ENABLE_COSTMULT
  LogEst costMult;     /* Cost multiplier for using this table */
#endif
  u8 keyConf;          /* What to do in case of uniqueness conflict on iPKey */
  u8 eTabType;         /* 0: normal, 1: virtual, 2: view */
  union {
    struct {             /* Used by ordinary tables: */
      int addColOffset;    /* Offset in CREATE TABLE stmt to add a new column */
      FKey *pFKey;         /* Linked list of all foreign keys in this table */
      ExprList *pDfltList; /* DEFAULT clauses on various columns.
                           ** Or the AS clause for generated columns. */
    } tab;
    struct {             /* Used by views: */
      Select *pSelect;     /* View definition */
    } view;
    struct {             /* Used by virtual tables only: */
      int nArg;            /* Number of arguments to the module */
      char **azArg;        /* 0: module 1: schema 2: vtab name 3...: args */
      VTable *p;           /* List of VTable objects. */
    } vtab;
  } u;
  Trigger *pTrigger;   /* List of triggers on this object */
  Schema *pSchema;     /* Schema that contains this table */
  u8 aHx[16];          /* Column aHt[K%sizeof(aHt)] might have hash K */
};

/*
** Allowed values for Table.tabFlags.
**
** TF_OOOHidden applies to tables or view that have hidden columns that are
** followed by non-hidden columns.  Example:  "CREATE VIRTUAL TABLE x USING
** vtab1(a HIDDEN, b);".  Since "b" is a non-hidden column but "a" is hidden,
** the TF_OOOHidden attribute would apply in this case.  Such tables require
** special handling during INSERT processing. The "OOO" means "Out Of Order".
**
** Constraints:
**
**         TF_HasVirtual == COLFLAG_VIRTUAL
**         TF_HasStored  == COLFLAG_STORED
**         TF_HasHidden  == COLFLAG_HIDDEN
*/
#define TF_Readonly       0x00000001 /* Read-only system table */
#define TF_HasHidden      0x00000002 /* Has one or more hidden columns */
#define TF_HasPrimaryKey  0x00000004 /* Table has a primary key */
#define TF_Autoincrement  0x00000008 /* Integer primary key is autoincrement */
#define TF_HasStat1       0x00000010 /* nRowLogEst set from sqlite_stat1 */
#define TF_HasVirtual     0x00000020 /* Has one or more VIRTUAL columns */
#define TF_HasStored      0x00000040 /* Has one or more STORED columns */
#define TF_HasGenerated   0x00000060 /* Combo: HasVirtual + HasStored */
#define TF_WithoutRowid   0x00000080 /* No rowid.  PRIMARY KEY is the key */
#define TF_MaybeReanalyze 0x00000100 /* Maybe run ANALYZE on this table */
#define TF_NoVisibleRowid 0x00000200 /* No user-visible "rowid" column */
#define TF_OOOHidden      0x00000400 /* Out-of-Order hidden columns */
#define TF_HasNotNull     0x00000800 /* Contains NOT NULL constraints */
#define TF_Shadow         0x00001000 /* True for a shadow table */
#define TF_HasStat4       0x00002000 /* STAT4 info available for this table */
#define TF_Ephemeral      0x00004000 /* An ephemeral table */
#define TF_Eponymous      0x00008000 /* An eponymous virtual table */
#define TF_Strict         0x00010000 /* STRICT mode */
#define TF_Imposter       0x00020000 /* An imposter table */

/*
** Allowed values for Table.eTabType
*/
#define TABTYP_NORM      0     /* Ordinary table */
#define TABTYP_VTAB      1     /* Virtual table */
#define TABTYP_VIEW      2     /* A view */

#define IsView(X)           ((X)->eTabType==TABTYP_VIEW)
#define IsOrdinaryTable(X)  ((X)->eTabType==TABTYP_NORM)

/*
** 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()
** only works for non-virtual tables (ordinary tables and views) and is
** always false unless SQLITE_ENABLE_HIDDEN_COLUMNS is defined.  The
** IsHiddenColumn() macro is general purpose.
*/
#if defined(SQLITE_ENABLE_HIDDEN_COLUMNS)
#  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#  define IsOrdinaryHiddenColumn(X) (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#elif !defined(SQLITE_OMIT_VIRTUALTABLE)
#  define IsHiddenColumn(X)         (((X)->colFlags & COLFLAG_HIDDEN)!=0)
#  define IsOrdinaryHiddenColumn(X) 0
#else
#  define IsHiddenColumn(X)         0
#  define IsOrdinaryHiddenColumn(X) 0
#endif


/* Does the table have a rowid */
#define HasRowid(X)     (((X)->tabFlags & TF_WithoutRowid)==0)
#define VisibleRowid(X) (((X)->tabFlags & TF_NoVisibleRowid)==0)

/* Macro is true if the SQLITE_ALLOW_ROWID_IN_VIEW (mis-)feature is
** available.  By default, this macro is false
*/
#ifndef SQLITE_ALLOW_ROWID_IN_VIEW
# define ViewCanHaveRowid     0
#else
# define ViewCanHaveRowid     (sqlite3Config.mNoVisibleRowid==0)
#endif

/*
** Each foreign key constraint is an instance of the following structure.
**
** A foreign key is associated with two tables.  The "from" table is
** the table that contains the REFERENCES clause that creates the foreign
** key.  The "to" table is the table that is named in the REFERENCES clause.
** Consider this example:
**
**     CREATE TABLE ex1(
**       a INTEGER PRIMARY KEY,
**       b INTEGER CONSTRAINT fk1 REFERENCES ex2(x)
**     );
**
** For foreign key "fk1", the from-table is "ex1" and the to-table is "ex2".
** Equivalent names:
**
**     from-table == child-table
**       to-table == parent-table
**
** Each REFERENCES clause generates an instance of the following structure
** which is attached to the from-table.  The to-table need not exist when
** the from-table is created.  The existence of the to-table is not checked.
**
** The list of all parents for child Table X is held at X.pFKey.
**
** A list of all children for a table named Z (which might not even exist)
** is held in Schema.fkeyHash with a hash key of Z.
*/
struct FKey {
  Table *pFrom;     /* Table containing the REFERENCES clause (aka: Child) */
  FKey *pNextFrom;  /* Next FKey with the same in pFrom. Next parent of pFrom */
  char *zTo;        /* Name of table that the key points to (aka: Parent) */
  FKey *pNextTo;    /* Next with the same zTo. Next child of zTo. */
  FKey *pPrevTo;    /* Previous with the same zTo */
  int nCol;         /* Number of columns in this key */
  /* EV: R-30323-21917 */
  u8 isDeferred;       /* True if constraint checking is deferred till COMMIT */
  u8 aAction[2];        /* ON DELETE and ON UPDATE actions, respectively */
  Trigger *apTrigger[2];/* Triggers for aAction[] actions */
  struct sColMap {      /* Mapping of columns in pFrom to columns in zTo */
    int iFrom;            /* Index of column in pFrom */
    char *zCol;           /* Name of column in zTo.  If NULL use PRIMARY KEY */
  } aCol[FLEXARRAY];      /* One entry for each of nCol columns */
};

/* The size (in bytes) of an FKey object holding N columns.  The answer
** does NOT include space to hold the zTo name. */
#define SZ_FKEY(N)  (offsetof(FKey,aCol)+(N)*sizeof(struct sColMap))

/*
** SQLite supports many different ways to resolve a constraint
** error.  ROLLBACK processing means that a constraint violation
** causes the operation in process to fail and for the current transaction
** to be rolled back.  ABORT processing means the operation in process
** fails and any prior changes from that one operation are backed out,
** but the transaction is not rolled back.  FAIL processing means that
** the operation in progress stops and returns an error code.  But prior
** changes due to the same operation are not backed out and no rollback
** occurs.  IGNORE means that the particular row that caused the constraint
** error is not inserted or updated.  Processing continues and no error
** is returned.  REPLACE means that preexisting database rows that caused
** a UNIQUE constraint violation are removed so that the new insert or
** update can proceed.  Processing continues and no error is reported.
** UPDATE applies to insert operations only and means that the insert
** is omitted and the DO UPDATE clause of an upsert is run instead.
**
** RESTRICT, SETNULL, SETDFLT, and CASCADE actions apply only to foreign keys.
** RESTRICT is the same as ABORT for IMMEDIATE foreign keys and the
** same as ROLLBACK for DEFERRED keys.  SETNULL means that the foreign
** key is set to NULL.  SETDFLT means that the foreign key is set
** to its default value.  CASCADE means that a DELETE or UPDATE of the
** referenced table row is propagated into the row that holds the
** foreign key.
**
** The OE_Default value is a place holder that means to use whatever
** conflict resolution algorithm is required from context.
**
** The following symbolic values are used to record which type
** of conflict resolution action to take.
*/
#define OE_None     0   /* There is no constraint to check */
#define OE_Rollback 1   /* Fail the operation and rollback the transaction */
#define OE_Abort    2   /* Back out changes but do no rollback transaction */
#define OE_Fail     3   /* Stop the operation but leave all prior changes */
#define OE_Ignore   4   /* Ignore the error. Do not do the INSERT or UPDATE */
#define OE_Replace  5   /* Delete existing record, then do INSERT or UPDATE */
#define OE_Update   6   /* Process as a DO UPDATE in an upsert */
#define OE_Restrict 7   /* OE_Abort for IMMEDIATE, OE_Rollback for DEFERRED */
#define OE_SetNull  8   /* Set the foreign key value to NULL */
#define OE_SetDflt  9   /* Set the foreign key value to its default */
#define OE_Cascade  10  /* Cascade the changes */
#define OE_Default  11  /* Do whatever the default action is */


/*
** An instance of the following structure is passed as the first
** argument to sqlite3VdbeKeyCompare and is used to control the
** comparison of the two index keys.
**
** The aSortOrder[] and aColl[] arrays have nAllField slots each. There
** are nKeyField slots for the columns of an index then extra slots
** for the rowid or key at the end.  The aSortOrder array is located after
** the aColl[] array.
**
** If SQLITE_ENABLE_PREUPDATE_HOOK is defined, then aSortFlags might be NULL
** to indicate that this object is for use by a preupdate hook.  When aSortFlags
** is NULL, then nAllField is uninitialized and no space is allocated for
** aColl[], so those fields may not be used.
*/
struct KeyInfo {
  u32 nRef;           /* Number of references to this KeyInfo object */
  u8 enc;             /* Text encoding - one of the SQLITE_UTF* values */
  u16 nKeyField;      /* Number of key columns in the index */
  u16 nAllField;      /* Total columns, including key plus others */
  sqlite3 *db;        /* The database connection */
  u8 *aSortFlags;     /* Sort order for each column. */
  CollSeq *aColl[FLEXARRAY]; /* Collating sequence for each term of the key */
};

/* The size (in bytes) of a KeyInfo object with up to N fields.  This includes
** the main body of the KeyInfo object and the aColl[] array of N elements,
** but does not count the memory used to hold aSortFlags[]. */
#define SZ_KEYINFO(N)  (offsetof(KeyInfo,aColl) + (N)*sizeof(CollSeq*))

/* The size of a bare KeyInfo with no aColl[] entries */
#if FLEXARRAY+1 > 1
# define SZ_KEYINFO_0   offsetof(KeyInfo,aColl)
#else
# define SZ_KEYINFO_0   sizeof(KeyInfo)
#endif

/*
** Allowed bit values for entries in the KeyInfo.aSortFlags[] array.
*/
#define KEYINFO_ORDER_DESC    0x01    /* DESC sort order */
#define KEYINFO_ORDER_BIGNULL 0x02    /* NULL is larger than any other value */

/*
** This object holds a record which has been parsed out into individual
** fields, for the purposes of doing a comparison.
**
** A record is an object that contains one or more fields of data.
** Records are used to store the content of a table row and to store
** the key of an index.  A blob encoding of a record is created by
** the OP_MakeRecord opcode of the VDBE and is disassembled by the
** OP_Column opcode.
**
** An instance of this object serves as a "key" for doing a search on
** an index b+tree. The goal of the search is to find the entry that
** is closest to the key described by this object.  This object might hold
** just a prefix of the key.  The number of fields is given by nField.
**
** The r1 and r2 fields are the values to return if this key is less than
** or greater than a key in the btree, respectively.  These are normally
** -1 and +1 respectively, but might be inverted to +1 and -1 if the b-tree
** is in DESC order.
**
** The key comparison functions actually return default_rc when they find
** an equals comparison.  default_rc can be -1, 0, or +1.  If there are
** multiple entries in the b-tree with the same key (when only looking
** at the first nField elements) then default_rc can be set to -1 to
** cause the search to find the last match, or +1 to cause the search to
** find the first match.
**
** The key comparison functions will set eqSeen to true if they ever
** get and equal results when comparing this structure to a b-tree record.
** When default_rc!=0, the search might end up on the record immediately
** before the first match or immediately after the last match.  The
** eqSeen field will indicate whether or not an exact match exists in the
** b-tree.
*/
struct UnpackedRecord {
  KeyInfo *pKeyInfo;  /* Comparison info for the index that is unpacked */
  Mem *aMem;          /* Values for columns of the index */
  union {
    char *z;            /* Cache of aMem[0].z for vdbeRecordCompareString() */
    i64 i;              /* Cache of aMem[0].u.i for vdbeRecordCompareInt() */
  } u;
  int n;              /* Cache of aMem[0].n used by vdbeRecordCompareString() */
  u16 nField;         /* Number of entries in apMem[] */
  i8 default_rc;      /* Comparison result if keys are equal */
  u8 errCode;         /* Error detected by xRecordCompare (CORRUPT or NOMEM) */
  i8 r1;              /* Value to return if (lhs < rhs) */
  i8 r2;              /* Value to return if (lhs > rhs) */
  u8 eqSeen;          /* True if an equality comparison has been seen */
};


/*
** Each SQL index is represented in memory by an
** instance of the following structure.
**
** The columns of the table that are to be indexed are described
** by the aiColumn[] field of this structure.  For example, suppose
** we have the following table and index:
**
**     CREATE TABLE Ex1(c1 int, c2 int, c3 text);
**     CREATE INDEX Ex2 ON Ex1(c3,c1);
**
** In the Table structure describing Ex1, nCol==3 because there are
** three columns in the table.  In the Index structure describing
** Ex2, nColumn==2 since 2 of the 3 columns of Ex1 are indexed.
** The value of aiColumn is {2, 0}.  aiColumn[0]==2 because the
** 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
** program is executed). See convertToWithoutRowidTable() for details.
*/
struct Index {
  char *zName;             /* Name of this index */
  i16 *aiColumn;           /* Which columns are used by this index.  1st is 0 */
  LogEst *aiRowLogEst;     /* From ANALYZE: Est. rows selected by each column */
  Table *pTable;           /* The SQL table being indexed */
  char *zColAff;           /* String defining the affinity of each column */
  Index *pNext;            /* The next index associated with the same table */
  Schema *pSchema;         /* Schema containing this index */
  u8 *aSortOrder;          /* for each column: True==DESC, False==ASC */
  const char **azColl;     /* Array of collation sequence names for index */
  Expr *pPartIdxWhere;     /* WHERE clause for partial indices */
  ExprList *aColExpr;      /* Column expressions */
  Pgno tnum;               /* DB Page containing root of this index */
  LogEst szIdxRow;         /* Estimated average row size in bytes */
  u16 nKeyCol;             /* Number of columns forming the key */
  u16 nColumn;             /* Nr columns in btree. Can be 2*Table.nCol */
  u8 onError;              /* OE_Abort, OE_Ignore, OE_Replace, or OE_None */
  unsigned idxType:2;      /* 0:Normal 1:UNIQUE, 2:PRIMARY KEY, 3:IPK */
  unsigned bUnordered:1;   /* Use this index for == or IN queries only */
  unsigned uniqNotNull:1;  /* True if UNIQUE and NOT NULL for all columns */
  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 mxSample;            /* Number of slots allocated to aSample[] */
  int nSampleCol;          /* Size of IndexSample.anEq[] and so on */
  tRowcnt *aAvgEq;         /* Average nEq values for keys not in aSample */
  IndexSample *aSample;    /* Samples of the left-most key */
  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 SQLITE_IDXTYPE_PRIMARYKEY  2   /* Is the PRIMARY KEY for the table */
#define SQLITE_IDXTYPE_IPK         3   /* INTEGER PRIMARY KEY index */

/* Return true if index X is a PRIMARY KEY index */
#define IsPrimaryKeyIndex(X)  ((X)->idxType==SQLITE_IDXTYPE_PRIMARYKEY)

/* Return true if index X is a UNIQUE index */
#define IsUniqueIndex(X)      ((X)->onError!=OE_None)

/* The Index.aiColumn[] values are normally positive integer.  But
** there are some negative values that have special meaning:
*/
#define XN_ROWID     (-1)     /* Indexed column is the rowid */
#define XN_EXPR      (-2)     /* Indexed column is an expression */

/*
** Each sample stored in the sqlite_stat4 table is represented in memory
** using a structure of this type.  See documentation at the top of the
** analyze.c source file for additional information.
*/
struct IndexSample {
  void *p;          /* Pointer to sampled record */
  int n;            /* Size of record in bytes */
  tRowcnt *anEq;    /* Est. number of rows where the key equals this sample */
  tRowcnt *anLt;    /* Est. number of rows where key is less than this sample */
  tRowcnt *anDLt;   /* Est. number of distinct keys less than this sample */
};

/*
** Possible values to use within the flags argument to sqlite3GetToken().
*/
#define SQLITE_TOKEN_QUOTED    0x1 /* Token is a quoted identifier. */
#define SQLITE_TOKEN_KEYWORD   0x2 /* Token is a keyword. */

/*
** Each token coming out of the lexer is an instance of
** this structure.  Tokens are also used as part of an expression.
**
** The memory that "z" points to is owned by other objects.  Take care
** that the owner of the "z" string does not deallocate the string before
** the Token goes out of scope!  Very often, the "z" points to some place
** in the middle of the Parse.zSql text.  But it might also point to a
** static string.
*/
struct Token {
  const char *z;     /* Text of the token.  Not NULL-terminated! */
  unsigned int n;    /* Number of characters in this token */
};

/*
** An instance of this structure contains information needed to generate
** code for a SELECT that contains aggregate functions.
**
** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
** pointer to this structure.  The Expr.iAgg field is the index in
** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
** code for that node.
**
** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
** original Select structure that describes the SELECT statement.  These
** fields do not need to be freed when deallocating the AggInfo structure.
*/
struct AggInfo {
  u8 directMode;          /* Direct rendering mode means take data directly
                          ** from source tables rather than from accumulators */
  u8 useSortingIdx;       /* In direct mode, reference the sorting index rather
                          ** than the source table */
  u32 nSortingColumn;     /* Number of columns in the sorting index */
  int sortingIdx;         /* Cursor number of the sorting index */
  int sortingIdxPTab;     /* Cursor number of pseudo-table */
  int iFirstReg;          /* First register in range for aCol[] and aFunc[] */
  ExprList *pGroupBy;     /* The group by clause */
  struct AggInfo_col {    /* For each column used in source tables */
    Table *pTab;             /* Source table */
    Expr *pCExpr;            /* The original expression */
    int iTable;              /* Cursor number of the source table */
    int iColumn;             /* Column number within the source table */
    int iSorterColumn;       /* Column number in the sorting index */
  } *aCol;
  int nColumn;            /* Number of used entries in aCol[] */
  int nAccumulator;       /* Number of columns that show through to the output.
                          ** Additional columns are used only as parameters to
                          ** aggregate functions */
  struct AggInfo_func {   /* For each aggregate function */
    Expr *pFExpr;            /* Expression encoding the function */
    FuncDef *pFunc;          /* The aggregate function implementation */
    int iDistinct;           /* Ephemeral table used to enforce DISTINCT */
    int iDistAddr;           /* Address of OP_OpenEphemeral */
    int iOBTab;              /* Ephemeral table to implement ORDER BY */
    u8 bOBPayload;           /* iOBTab has payload columns separate from key */
    u8 bOBUnique;            /* Enforce uniqueness on iOBTab keys */
    u8 bUseSubtype;          /* Transfer subtype info through sorter */
  } *aFunc;
  int nFunc;              /* Number of entries in aFunc[] */
  u32 selId;              /* Select to which this AggInfo belongs */
#ifdef SQLITE_DEBUG
  Select *pSelect;        /* SELECT statement that this AggInfo supports */
#endif
};

/*
** Macros to compute aCol[] and aFunc[] register numbers.
**
** These macros should not be used prior to the call to
** assignAggregateRegisters() that computes the value of pAggInfo->iFirstReg.
** The assert()s that are part of this macro verify that constraint.
*/
#ifndef NDEBUG
#define AggInfoColumnReg(A,I)  (assert((A)->iFirstReg),(A)->iFirstReg+(I))
#define AggInfoFuncReg(A,I)    \
                      (assert((A)->iFirstReg),(A)->iFirstReg+(A)->nColumn+(I))
#else
#define AggInfoColumnReg(A,I)  ((A)->iFirstReg+(I))
#define AggInfoFuncReg(A,I)    \
                      ((A)->iFirstReg+(A)->nColumn+(I))
#endif

/*
** The datatype ynVar is a signed integer, either 16-bit or 32-bit.
** Usually it is 16-bits.  But if SQLITE_MAX_VARIABLE_NUMBER is greater
** than 32767 we have to make it 32-bit.  16-bit is preferred because
** it uses less memory in the Expr object, which is a big memory user
** in systems with lots of prepared statements.  And few applications
** need more than about 10 or 20 variables.  But some extreme users want
** to have prepared statements with over 32766 variables, and for them
** the option is available (at compile-time).
*/
#if SQLITE_MAX_VARIABLE_NUMBER0
  int nHeight;           /* Height of the tree headed by this node */
#endif
  int iTable;            /* TK_COLUMN: cursor number of table holding column
                         ** TK_REGISTER: register number
                         ** TK_TRIGGER: 1 -> new, 0 -> old
                         ** EP_Unlikely:  134217728 times likelihood
                         ** TK_IN: ephemeral table holding RHS
                         ** TK_SELECT_COLUMN: Number of columns on the LHS
                         ** TK_SELECT: 1st register of result vector */
  ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
                         ** TK_VARIABLE: variable number (always >= 1).
                         ** TK_SELECT_COLUMN: column of the result vector */
  i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
  union {
    int iJoin;             /* If EP_OuterON or EP_InnerON, the right table */
    int iOfst;             /* else: start of token from start of statement */
  } w;
  AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
  union {
    Table *pTab;           /* TK_COLUMN: Table containing column. Can be NULL
                           ** for a column of an index on an expression */
    Window *pWin;          /* EP_WinFunc: Window/Filter defn for a function */
    int nReg;              /* TK_NULLS: Number of registers to NULL out */
    struct {               /* TK_IN, TK_SELECT, and TK_EXISTS */
      int iAddr;             /* Subroutine entry address */
      int regReturn;         /* Register used to hold return address */
    } sub;
  } y;
};

/* The following are the meanings of bits in the Expr.flags field.
** Value restrictions:
**
**          EP_Agg == NC_HasAgg == SF_HasAgg
**          EP_Win == NC_HasWin
*/
#define EP_OuterON    0x000001 /* Originates in ON/USING clause of outer join */
#define EP_InnerON    0x000002 /* Originates in ON/USING of an inner join */
#define EP_Distinct   0x000004 /* Aggregate function with DISTINCT keyword */
#define EP_HasFunc    0x000008 /* Contains one or more functions of any kind */
#define EP_Agg        0x000010 /* Contains one or more aggregate functions */
#define EP_FixedCol   0x000020 /* TK_Column with a known fixed value */
#define EP_VarSelect  0x000040 /* pSelect is correlated, not constant */
#define EP_DblQuoted  0x000080 /* token.z was originally in "..." */
#define EP_InfixFunc  0x000100 /* True for an infix function: LIKE, GLOB, etc */
#define EP_Collate    0x000200 /* Tree contains a TK_COLLATE operator */
#define EP_Commuted   0x000400 /* Comparison operator has been commuted */
#define EP_IntValue   0x000800 /* Integer value contained in u.iValue */
#define EP_xIsSelect  0x001000 /* x.pSelect is valid (otherwise x.pList is) */
#define EP_Skip       0x002000 /* Operator does not contribute to affinity */
#define EP_Reduced    0x004000 /* Expr struct EXPR_REDUCEDSIZE bytes only */
#define EP_Win        0x008000 /* Contains window functions */
#define EP_TokenOnly  0x010000 /* Expr struct EXPR_TOKENONLYSIZE bytes only */
#define EP_FullSize   0x020000 /* Expr structure must remain full sized */
#define EP_IfNullRow  0x040000 /* The TK_IF_NULL_ROW opcode */
#define EP_Unlikely   0x080000 /* unlikely() or likelihood() function */
#define EP_ConstFunc  0x100000 /* A SQLITE_FUNC_CONSTANT or _SLOCHNG function */
#define EP_CanBeNull  0x200000 /* Can be null despite NOT NULL constraint */
#define EP_Subquery   0x400000 /* Tree contains a TK_SELECT operator */
#define EP_Leaf       0x800000 /* Expr.pLeft, .pRight, .u.pSelect all NULL */
#define EP_WinFunc   0x1000000 /* TK_FUNCTION with Expr.y.pWin set */
#define EP_Subrtn    0x2000000 /* Uses Expr.y.sub. TK_IN, _SELECT, or _EXISTS */
#define EP_Quoted    0x4000000 /* TK_ID was originally quoted */
#define EP_Static    0x8000000 /* Held in memory not obtained from malloc() */
#define EP_IsTrue   0x10000000 /* Always has boolean value of TRUE */
#define EP_IsFalse  0x20000000 /* Always has boolean value of FALSE */
#define EP_FromDDL  0x40000000 /* Originates from sqlite_schema */
#define EP_SubtArg  0x80000000 /* Is argument to SQLITE_SUBTYPE function */

/* The EP_Propagate mask is a set of properties that automatically propagate
** upwards into parent nodes.
*/
#define EP_Propagate (EP_Collate|EP_Subquery|EP_HasFunc)

/* Macros can be used to test, set, or clear bits in the
** Expr.flags field.
*/
#define ExprHasProperty(E,P)     (((E)->flags&(u32)(P))!=0)
#define ExprHasAllProperty(E,P)  (((E)->flags&(u32)(P))==(u32)(P))
#define ExprSetProperty(E,P)     (E)->flags|=(u32)(P)
#define ExprClearProperty(E,P)   (E)->flags&=~(u32)(P)
#define ExprAlwaysTrue(E)   (((E)->flags&(EP_OuterON|EP_IsTrue))==EP_IsTrue)
#define ExprAlwaysFalse(E)  (((E)->flags&(EP_OuterON|EP_IsFalse))==EP_IsFalse)
#define ExprIsFullSize(E)   (((E)->flags&(EP_Reduced|EP_TokenOnly))==0)

/* Macros used to ensure that the correct members of unions are accessed
** in Expr.
*/
#define ExprUseUToken(E)    (((E)->flags&EP_IntValue)==0)
#define ExprUseUValue(E)    (((E)->flags&EP_IntValue)!=0)
#define ExprUseWOfst(E)     (((E)->flags&(EP_InnerON|EP_OuterON))==0)
#define ExprUseWJoin(E)     (((E)->flags&(EP_InnerON|EP_OuterON))!=0)
#define ExprUseXList(E)     (((E)->flags&EP_xIsSelect)==0)
#define ExprUseXSelect(E)   (((E)->flags&EP_xIsSelect)!=0)
#define ExprUseYTab(E)      (((E)->flags&(EP_WinFunc|EP_Subrtn))==0)
#define ExprUseYWin(E)      (((E)->flags&EP_WinFunc)!=0)
#define ExprUseYSub(E)      (((E)->flags&EP_Subrtn)!=0)

/* Flags for use with Expr.vvaFlags
*/
#define EP_NoReduce   0x01  /* Cannot EXPRDUP_REDUCE this Expr */
#define EP_Immutable  0x02  /* Do not change this Expr node */

/* The ExprSetVVAProperty() macro is used for Verification, Validation,
** and Accreditation only.  It works like ExprSetProperty() during VVA
** processes but is a no-op for delivery.
*/
#ifdef SQLITE_DEBUG
# define ExprSetVVAProperty(E,P)   (E)->vvaFlags|=(P)
# define ExprHasVVAProperty(E,P)   (((E)->vvaFlags&(P))!=0)
# define ExprClearVVAProperties(E) (E)->vvaFlags = 0
#else
# define ExprSetVVAProperty(E,P)
# define ExprHasVVAProperty(E,P)   0
# define ExprClearVVAProperties(E)
#endif

/*
** Macros to determine the number of bytes required by a normal Expr
** struct, an Expr struct with the EP_Reduced flag set in Expr.flags
** and an Expr struct with the EP_TokenOnly flag set.
*/
#define EXPR_FULLSIZE           sizeof(Expr)           /* Full size */
#define EXPR_REDUCEDSIZE        offsetof(Expr,iTable)  /* Common features */
#define EXPR_TOKENONLYSIZE      offsetof(Expr,pLeft)   /* Fewer features */

/*
** Flags passed to the sqlite3ExprDup() function. See the header comment
** above sqlite3ExprDup() for details.
*/
#define EXPRDUP_REDUCE         0x0001  /* Used reduced-size Expr nodes */

/*
** True if the expression passed as an argument was a function with
** an OVER() clause (a window function).
*/
#ifdef SQLITE_OMIT_WINDOWFUNC
# define IsWindowFunc(p) 0
#else
# define IsWindowFunc(p) ( \
    ExprHasProperty((p), EP_WinFunc) && p->y.pWin->eFrmType!=TK_FILTER \
 )
#endif

/*
** A list of expressions.  Each expression may optionally have a
** name.  An expr/name combination can be used in several ways, such
** as the list of "expr AS ID" fields following a "SELECT" or in the
** list of "ID = expr" items in an UPDATE.  A list of expressions can
** also be used as the argument to a function, in which case the a.zName
** field is not used.
**
** In order to try to keep memory usage down, the Expr.a.zEName field
** is used for multiple purposes:
**
**     eEName          Usage
**    ----------       -------------------------
**    ENAME_NAME       (1) the AS of result set column
**                     (2) COLUMN= of an UPDATE
**
**    ENAME_TAB        DB.TABLE.NAME used to resolve names
**                     of subqueries
**
**    ENAME_SPAN       Text of the original result set
**                     expression.
*/
struct ExprList {
  int nExpr;             /* Number of expressions on the list */
  int nAlloc;            /* Number of a[] slots allocated */
  struct ExprList_item { /* For each expression in the list */
    Expr *pExpr;            /* The parse tree for this expression */
    char *zEName;           /* Token associated with this expression */
    struct {
      u8 sortFlags;           /* Mask of KEYINFO_ORDER_* flags */
      unsigned eEName :2;     /* Meaning of zEName */
      unsigned done :1;       /* Indicates when processing is finished */
      unsigned reusable :1;   /* Constant expression is reusable */
      unsigned bSorterRef :1; /* Defer evaluation until after sorting */
      unsigned bNulls :1;     /* True if explicit "NULLS FIRST/LAST" */
      unsigned bUsed :1;      /* This column used in a SF_NestedFrom subquery */
      unsigned bUsingTerm:1;  /* Term from the USING clause of a NestedFrom */
      unsigned bNoExpand: 1;  /* Term is an auxiliary in NestedFrom and should
                              ** not be expanded by "*" in parent queries */
    } fg;
    union {
      struct {             /* Used by any ExprList other than Parse.pConsExpr */
        u16 iOrderByCol;      /* For ORDER BY, column number in result set */
        u16 iAlias;           /* Index into Parse.aAlias[] for zName */
      } x;
      int iConstExprReg;   /* Register in which Expr value is cached. Used only
                           ** by Parse.pConstExpr */
    } u;
  } a[FLEXARRAY];          /* One slot for each expression in the list */
};

/* The size (in bytes) of an ExprList object that is big enough to hold
** as many as N expressions. */
#define SZ_EXPRLIST(N)  \
             (offsetof(ExprList,a) + (N)*sizeof(struct ExprList_item))

/*
** Allowed values for Expr.a.eEName
*/
#define ENAME_NAME  0       /* The AS clause of a result set */
#define ENAME_SPAN  1       /* Complete text of the result set expression */
#define ENAME_TAB   2       /* "DB.TABLE.NAME" for the result set */
#define ENAME_ROWID 3       /* "DB.TABLE._rowid_" for * expansion of rowid */

/*
** An instance of this structure can hold a simple list of identifiers,
** such as the list "a,b,c" in the following statements:
**
**      INSERT INTO t(a,b,c) VALUES ...;
**      CREATE INDEX idx ON t(a,b,c);
**      CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
**
** The IdList.a.idx field is used when the IdList represents the list of
** column names after a table name in an INSERT statement.  In the statement
**
**     INSERT INTO t(a,b,c) ...
**
** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
*/
struct IdList {
  int nId;         /* Number of identifiers on the list */
  struct IdList_item {
    char *zName;      /* Name of the identifier */
  } a[FLEXARRAY];
};

/* The size (in bytes) of an IdList object that can hold up to N IDs. */
#define SZ_IDLIST(N)  (offsetof(IdList,a)+(N)*sizeof(struct IdList_item))

/*
** Allowed values for IdList.eType, which determines which value of the a.u4
** is valid.
*/
#define EU4_NONE   0   /* Does not use IdList.a.u4 */
#define EU4_IDX    1   /* Uses IdList.a.u4.idx */
#define EU4_EXPR   2   /* Uses IdList.a.u4.pExpr -- NOT CURRENTLY USED */

/*
** Details of the implementation of a subquery.
*/
struct Subquery {
  Select *pSelect;  /* A SELECT statement used in place of a table name */
  int addrFillSub;  /* Address of subroutine to initialize a subquery */
  int regReturn;    /* Register holding return address of addrFillSub */
  int regResult;    /* Registers holding results of a co-routine */
};

/*
** 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.
**
** Aggressive use of "union" helps keep the size of the object small.  This
** has been shown to boost performance, in addition to saving memory.
** Access to union elements is gated by the following rules which should
** always be checked, either by an if-statement or by an assert().
**
**    Field              Only access if this is true
**    ---------------    -----------------------------------
**    u1.zIndexedBy      fg.isIndexedBy
**    u1.pFuncArg        fg.isTabFunc
**    u1.nRow            !fg.isTabFunc  && !fg.isIndexedBy
**
**    u2.pIBIndex        fg.isIndexedBy
**    u2.pCteUse         fg.isCte
**
**    u3.pOn             !fg.isUsing
**    u3.pUsing          fg.isUsing
**
**    u4.zDatabase       !fg.fixedSchema && !fg.isSubquery
**    u4.pSchema         fg.fixedSchema
**    u4.pSubq           fg.isSubquery
**
** See also the sqlite3SrcListDelete() routine for assert() statements that
** check invariants on the fields of this object, especially the flags
** inside the fg struct.
*/
struct SrcItem {
  char *zName;      /* Name of the table */
  char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
  Table *pSTab;     /* Table object for zName. Mnemonic: Srcitem-TABle */
  struct {
    u8 jointype;      /* Type of join between this table and the previous */
    unsigned notIndexed :1;    /* True if there is a NOT INDEXED clause */
    unsigned isIndexedBy :1;   /* True if there is an INDEXED BY clause */
    unsigned isSubquery :1;    /* True if this term is a subquery */
    unsigned isTabFunc :1;     /* True if table-valued-function syntax */
    unsigned isCorrelated :1;  /* True if sub-query is correlated */
    unsigned isMaterialized:1; /* This is a materialized view */
    unsigned viaCoroutine :1;  /* Implemented as a co-routine */
    unsigned isRecursive :1;   /* True for recursive reference in WITH */
    unsigned fromDDL :1;       /* Comes from sqlite_schema */
    unsigned isCte :1;         /* This is a CTE */
    unsigned notCte :1;        /* This item may not match a CTE */
    unsigned isUsing :1;       /* u3.pUsing is valid */
    unsigned isOn :1;          /* u3.pOn was once valid and non-NULL */
    unsigned isSynthUsing :1;  /* u3.pUsing is synthesized from NATURAL */
    unsigned isNestedFrom :1;  /* pSelect is a SF_NestedFrom subquery */
    unsigned rowidUsed :1;     /* The ROWID of this table is referenced */
    unsigned fixedSchema :1;   /* Uses u4.pSchema, not u4.zDatabase */
    unsigned hadSchema :1;     /* Had u4.zDatabase before u4.pSchema */
    unsigned fromExists :1;    /* Comes from WHERE EXISTS(...) */
  } fg;
  int iCursor;      /* The VDBE cursor number used to access this table */
  Bitmask colUsed;  /* Bit N set if column N used. Details above for N>62 */
  union {
    char *zIndexedBy;    /* Identifier from "INDEXED BY " clause */
    ExprList *pFuncArg;  /* Arguments to table-valued-function */
    u32 nRow;            /* Number of rows in a VALUES clause */
  } u1;
  union {
    Index *pIBIndex;  /* Index structure corresponding to u1.zIndexedBy */
    CteUse *pCteUse;  /* CTE Usage info when fg.isCte is true */
  } u2;
  union {
    Expr *pOn;        /* fg.isUsing==0 =>  The ON clause of a join */
    IdList *pUsing;   /* fg.isUsing==1 =>  The USING clause of a join */
  } u3;
  union {
    Schema *pSchema;  /* Schema to which this item is fixed */
    char *zDatabase;  /* Name of database holding this table */
    Subquery *pSubq;  /* Description of a subquery */
  } u4;
};

/*
** 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[FLEXARRAY]; /* One entry for each identifier on the list */
};

/* Size (in bytes) of a SrcList object that can hold as many as N
** SrcItem objects. */
#define SZ_SRCLIST(N) (offsetof(SrcList,a)+(N)*sizeof(SrcItem))

/* Size (in bytes( of a SrcList object that holds 1 SrcItem.  This is a
** special case of SZ_SRCITEM(1) that comes up often. */
#define SZ_SRCLIST_1  (offsetof(SrcList,a)+sizeof(SrcItem))

/*
** Permitted values of the SrcList.a.jointype field
*/
#define JT_INNER     0x01    /* Any kind of inner or cross join */
#define JT_CROSS     0x02    /* Explicit use of the CROSS keyword */
#define JT_NATURAL   0x04    /* True for a "natural" join */
#define JT_LEFT      0x08    /* Left outer join */
#define JT_RIGHT     0x10    /* Right outer join */
#define JT_OUTER     0x20    /* The "OUTER" keyword is present */
#define JT_LTORJ     0x40    /* One of the LEFT operands of a RIGHT JOIN
                             ** Mnemonic: Left Table Of Right Join */
#define JT_ERROR     0x80    /* unknown or unsupported join type */

/*
** Flags appropriate for the wctrlFlags parameter of sqlite3WhereBegin()
** and the WhereInfo.wctrlFlags member.
**
** Value constraints (enforced via assert()):
**     WHERE_USE_LIMIT  == SF_FixedLimit
*/
#define WHERE_ORDERBY_NORMAL   0x0000 /* No-op */
#define WHERE_ORDERBY_MIN      0x0001 /* ORDER BY processing for min() func */
#define WHERE_ORDERBY_MAX      0x0002 /* ORDER BY processing for max() func */
#define WHERE_ONEPASS_DESIRED  0x0004 /* Want to do one-pass UPDATE/DELETE */
#define WHERE_ONEPASS_MULTIROW 0x0008 /* ONEPASS is ok with multiple rows */
#define WHERE_DUPLICATES_OK    0x0010 /* Ok to return a row more than once */
#define WHERE_OR_SUBCLAUSE     0x0020 /* Processing a sub-WHERE as part of
                                      ** the OR optimization  */
#define WHERE_GROUPBY          0x0040 /* pOrderBy is really a GROUP BY */
#define WHERE_DISTINCTBY       0x0080 /* pOrderby is really a DISTINCT clause */
#define WHERE_WANT_DISTINCT    0x0100 /* All output needs to be distinct */
#define WHERE_SORTBYGROUP      0x0200 /* Support sqlite3WhereIsSorted() */
#define WHERE_AGG_DISTINCT     0x0400 /* Query is "SELECT agg(DISTINCT ...)" */
#define WHERE_ORDERBY_LIMIT    0x0800 /* ORDERBY+LIMIT on the inner loop */
#define WHERE_RIGHT_JOIN       0x1000 /* Processing a RIGHT JOIN */
#define WHERE_KEEP_ALL_JOINS   0x2000 /* Do not do the omit-noop-join opt */
#define WHERE_USE_LIMIT        0x4000 /* Use the LIMIT in cost estimates */
                        /*     0x8000    not currently used */

/* Allowed return values from sqlite3WhereIsDistinct()
*/
#define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
#define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
#define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
#define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */

/*
** A NameContext defines a context in which to resolve table and column
** names.  The context consists of a list of tables (the pSrcList) field and
** a list of named expression (pEList).  The named expression list may
** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
** to the table being operated on by INSERT, UPDATE, or DELETE.  The
** pEList corresponds to the result set of a SELECT and is NULL for
** other statements.
**
** NameContexts can be nested.  When resolving names, the inner-most
** context is searched first.  If no match is found, the next outer
** context is checked.  If there is still no match, the next context
** is checked.  This process continues until either a match is found
** or all contexts are check.  When a match is found, the nRef member of
** the context containing the match is incremented.
**
** Each subquery gets a new NameContext.  The pNext field points to the
** NameContext in the parent query.  Thus the process of scanning the
** NameContext list corresponds to searching through successively outer
** subqueries looking for a match.
*/
struct NameContext {
  Parse *pParse;       /* The parser */
  SrcList *pSrcList;   /* One or more tables used to resolve names */
  union {
    ExprList *pEList;    /* Optional list of result-set columns */
    AggInfo *pAggInfo;   /* Information about aggregates at this level */
    Upsert *pUpsert;     /* ON CONFLICT clause information from an upsert */
    int iBaseReg;        /* For TK_REGISTER when parsing RETURNING */
  } uNC;
  NameContext *pNext;  /* Next outer name context.  NULL for outermost */
  int nRef;            /* Number of names resolved by this context */
  int nNcErr;          /* Number of errors encountered while resolving names */
  int ncFlags;         /* Zero or more NC_* flags defined below */
  u32 nNestedSelect;   /* Number of nested selects using this NC */
  Select *pWinSelect;  /* SELECT statement for any window functions */
};

/*
** Allowed values for the NameContext, ncFlags field.
**
** Value constraints (all checked via assert()):
**    NC_HasAgg    == SF_HasAgg       == EP_Agg
**    NC_MinMaxAgg == SF_MinMaxAgg    == SQLITE_FUNC_MINMAX
**    NC_OrderAgg  == SF_OrderByReqd  == SQLITE_FUNC_ANYORDER
**    NC_HasWin    == EP_Win
**
*/
#define NC_AllowAgg  0x000001 /* Aggregate functions are allowed here */
#define NC_PartIdx   0x000002 /* True if resolving a partial index WHERE */
#define NC_IsCheck   0x000004 /* True if resolving a CHECK constraint */
#define NC_GenCol    0x000008 /* True for a GENERATED ALWAYS AS clause */
#define NC_HasAgg    0x000010 /* One or more aggregate functions seen */
#define NC_IdxExpr   0x000020 /* True if resolving columns of CREATE INDEX */
#define NC_SelfRef   0x00002e /* Combo: PartIdx, isCheck, GenCol, and IdxExpr */
#define NC_Subquery  0x000040 /* A subquery has been seen */
#define NC_UEList    0x000080 /* True if uNC.pEList is used */
#define NC_UAggInfo  0x000100 /* True if uNC.pAggInfo is used */
#define NC_UUpsert   0x000200 /* True if uNC.pUpsert is used */
#define NC_UBaseReg  0x000400 /* True if uNC.iBaseReg is used */
#define NC_MinMaxAgg 0x001000 /* min/max aggregates seen.  See note above */
/*                   0x002000 // available for reuse */
#define NC_AllowWin  0x004000 /* Window functions are allowed here */
#define NC_HasWin    0x008000 /* One or more window functions seen */
#define NC_IsDDL     0x010000 /* Resolving names in a CREATE statement */
#define NC_InAggFunc 0x020000 /* True if analyzing arguments to an agg func */
#define NC_FromDDL   0x040000 /* SQL text comes from sqlite_schema */
#define NC_NoSelect  0x080000 /* Do not descend into sub-selects */
#define NC_Where     0x100000 /* Processing WHERE clause of a SELECT */
#define NC_OrderAgg 0x8000000 /* Has an aggregate other than count/min/max */

/*
** An instance of the following object describes a single ON CONFLICT
** clause in an upsert.
**
** The pUpsertTarget field is only set if the ON CONFLICT clause includes
** conflict-target clause.  (In "ON CONFLICT(a,b)" the "(a,b)" is the
** conflict-target clause.)  The pUpsertTargetWhere is the optional
** WHERE clause used to identify partial unique indexes.
**
** pUpsertSet is the list of column=expr terms of the UPDATE statement.
** The pUpsertSet field is NULL for a ON CONFLICT DO NOTHING.  The
** pUpsertWhere is the WHERE clause for the UPDATE and is NULL if the
** WHERE clause is omitted.
*/
struct Upsert {
  ExprList *pUpsertTarget;  /* Optional description of conflict target */
  Expr *pUpsertTargetWhere; /* WHERE clause for partial index targets */
  ExprList *pUpsertSet;     /* The SET clause from an ON CONFLICT UPDATE */
  Expr *pUpsertWhere;       /* WHERE clause for the ON CONFLICT UPDATE */
  Upsert *pNextUpsert;      /* Next ON CONFLICT clause in the list */
  u8 isDoUpdate;            /* True for DO UPDATE.  False for DO NOTHING */
  u8 isDup;                 /* True if 2nd or later with same pUpsertIdx */
  /* Above this point is the parse tree for the ON CONFLICT clauses.
  ** The next group of fields stores intermediate data. */
  void *pToFree;            /* Free memory when deleting the Upsert object */
  /* All fields above are owned by the Upsert object and must be freed
  ** when the Upsert is destroyed.  The fields below are used to transfer
  ** information from the INSERT processing down into the UPDATE processing
  ** while generating code.  The fields below are owned by the INSERT
  ** statement and will be freed by INSERT processing. */
  Index *pUpsertIdx;        /* UNIQUE constraint specified by pUpsertTarget */
  SrcList *pUpsertSrc;      /* Table to be updated */
  int regData;              /* First register holding array of VALUES */
  int iDataCur;             /* Index of the data cursor */
  int iIdxCur;              /* Index of the first index cursor */
};

/*
** An instance of the following structure contains all information
** needed to generate code for a single SELECT statement.
*/
struct Select {
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  LogEst nSelectRow;     /* Estimated number of result rows */
  u32 selFlags;          /* Various SF_* values */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
  u32 selId;             /* Unique identifier number for this SELECT */
  ExprList *pEList;      /* The fields of the result */
  SrcList *pSrc;         /* The FROM clause */
  Expr *pWhere;          /* The WHERE clause */
  ExprList *pGroupBy;    /* The GROUP BY clause */
  Expr *pHaving;         /* The HAVING clause */
  ExprList *pOrderBy;    /* The ORDER BY clause */
  Select *pPrior;        /* Prior select in a compound select statement */
  Select *pNext;         /* Next select to the left in a compound */
  Expr *pLimit;          /* LIMIT expression. NULL means not used. */
  With *pWith;           /* WITH clause attached to this select. Or NULL. */
#ifndef SQLITE_OMIT_WINDOWFUNC
  Window *pWin;          /* List of window functions */
  Window *pWinDefn;      /* List of named window definitions */
#endif
};

/*
** Allowed values for Select.selFlags.  The "SF" prefix stands for
** "Select Flag".
**
** Value constraints (all checked via assert())
**     SF_HasAgg      == NC_HasAgg
**     SF_MinMaxAgg   == NC_MinMaxAgg     == SQLITE_FUNC_MINMAX
**     SF_OrderByReqd == NC_OrderAgg      == SQLITE_FUNC_ANYORDER
**     SF_FixedLimit  == WHERE_USE_LIMIT
*/
#define SF_Distinct      0x0000001 /* Output should be DISTINCT */
#define SF_All           0x0000002 /* Includes the ALL keyword */
#define SF_Resolved      0x0000004 /* Identifiers have been resolved */
#define SF_Aggregate     0x0000008 /* Contains agg functions or a GROUP BY */
#define SF_HasAgg        0x0000010 /* Contains aggregate functions */
#define SF_ClonedRhsIn   0x0000020 /* Cloned RHS of an IN operator */
#define SF_Expanded      0x0000040 /* sqlite3SelectExpand() called on this */
#define SF_HasTypeInfo   0x0000080 /* FROM subqueries have Table metadata */
#define SF_Compound      0x0000100 /* Part of a compound query */
#define SF_Values        0x0000200 /* Synthesized from VALUES clause */
#define SF_MultiValue    0x0000400 /* Single VALUES term with multiple rows */
#define SF_NestedFrom    0x0000800 /* Part of a parenthesized FROM clause */
#define SF_MinMaxAgg     0x0001000 /* Aggregate containing min() or max() */
#define SF_Recursive     0x0002000 /* The recursive part of a recursive CTE */
#define SF_FixedLimit    0x0004000 /* nSelectRow set by a constant LIMIT */
/*                       0x0008000 // available for reuse */
#define SF_Converted     0x0010000 /* By convertCompoundSelectToSubquery() */
#define SF_IncludeHidden 0x0020000 /* Include hidden columns in output */
#define SF_ComplexResult 0x0040000 /* Result contains subquery or function */
#define SF_WhereBegin    0x0080000 /* Really a WhereBegin() call.  Debug Only */
#define SF_WinRewrite    0x0100000 /* Window function rewrite accomplished */
#define SF_View          0x0200000 /* SELECT statement is a view */
/*                       0x0400000 // available for reuse */
#define SF_UFSrcCheck    0x0800000 /* Check pSrc as required by UPDATE...FROM */
#define SF_PushDown      0x1000000 /* Modified by WHERE-clause push-down opt */
#define SF_MultiPart     0x2000000 /* Has multiple incompatible PARTITIONs */
#define SF_CopyCte       0x4000000 /* SELECT statement is a copy of a CTE */
#define SF_OrderByReqd   0x8000000 /* The ORDER BY clause may not be omitted */
#define SF_UpdateFrom   0x10000000 /* Query originates with UPDATE FROM */
#define SF_Correlated   0x20000000 /* True if references the outer context */
#define SF_OnToWhere    0x40000000 /* One or more ON clauses moved to WHERE */

/* True if SrcItem X is a subquery that has SF_NestedFrom */
#define IsNestedFrom(X) \
   ((X)->fg.isSubquery && \
    ((X)->u4.pSubq->pSelect->selFlags&SF_NestedFrom)!=0)

/*
** The results of a SELECT can be distributed in several ways, as defined
** by one of the following macros.  The "SRT" prefix means "SELECT Result
** Type".
**
**     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
**                     set is not empty.
**
**     SRT_Discard     Throw the results away.  This is used by SELECT
**                     statements within triggers whose only purpose is
**                     the side-effects of functions.
**
**     SRT_Output      Generate a row of output (using the OP_ResultRow
**                     opcode) for each row in the result set.
**
**     SRT_Mem         Only valid if the result is a single column.
**                     Store the first column of the first result row
**                     in register pDest->iSDParm then abandon the rest
**                     of the query.  This destination implies "LIMIT 1".
**
**     SRT_Set         The result must be a single column.  Store each
**                     row of result as the key in table pDest->iSDParm.
**                     Apply the affinity pDest->affSdst before storing
**                     results.  if pDest->iSDParm2 is positive, then it is
**                     a register holding a Bloom filter for the IN operator
**                     that should be populated in addition to the
**                     pDest->iSDParm table.  This SRT is used to
**                     implement "IN (SELECT ...)".
**
**     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
**                     the result there. The cursor is left open after
**                     returning.  This is like SRT_Table except that
**                     this destination uses OP_OpenEphemeral to create
**                     the table first.
**
**     SRT_Coroutine   Generate a co-routine that returns a new row of
**                     results each time it is invoked.  The entry point
**                     of the co-routine is stored in register pDest->iSDParm
**                     and the result row is stored in pDest->nDest registers
**                     starting with pDest->iSdst.
**
**     SRT_Table       Store results in temporary table pDest->iSDParm.
**     SRT_Fifo        This is like SRT_EphemTab except that the table
**                     is assumed to already be open.  SRT_Fifo has
**                     the additional property of being able to ignore
**                     the ORDER BY clause.
**
**     SRT_DistFifo    Store results in a temporary table pDest->iSDParm.
**                     But also use temporary table pDest->iSDParm+1 as
**                     a record of all prior results and ignore any duplicate
**                     rows.  Name means:  "Distinct Fifo".
**
**     SRT_Queue       Store results in priority queue pDest->iSDParm (really
**                     an index).  Append a sequence number so that all entries
**                     are distinct.
**
**     SRT_DistQueue   Store results in priority queue pDest->iSDParm only if
**                     the same record has never been stored before.  The
**                     index at pDest->iSDParm+1 hold all prior stores.
**
**     SRT_Upfrom      Store results in the temporary table already opened by
**                     pDest->iSDParm. If (pDest->iSDParmiSDParm>0), then the table is an index
**                     table. (pDest->iSDParm) is the number of key columns in
**                     each index record in this case.
*/
#define SRT_Exists       1  /* Store 1 if the result is not empty */
#define SRT_Discard      2  /* Do not save the results anywhere */
#define SRT_DistFifo     3  /* Like SRT_Fifo, but unique results only */
#define SRT_DistQueue    4  /* Like SRT_Queue, but unique results only */

/* The DISTINCT clause is ignored for all of the above.  Not that
** IgnorableDistinct() implies IgnorableOrderby() */
#define IgnorableDistinct(X) ((X->eDest)eDest)30
  typedef unsigned char yDbMask[(SQLITE_MAX_ATTACHED+9)/8];
# define DbMaskTest(M,I)    (((M)[(I)/8]&(1lastRowid */
#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
#define OPFLAG_ISNOOP        0x40    /* OP_Delete does pre-update-hook only */
#define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
#define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
#define OPFLAG_BYTELENARG    0xc0    /* OP_Column only for octet_length() */
#define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
#define OPFLAG_SEEKEQ        0x02    /* OP_Open** cursor uses EQ seek only */
#define OPFLAG_FORDELETE     0x08    /* OP_Open should use BTREE_FORDELETE */
#define OPFLAG_P2ISREG       0x10    /* P2 to OP_Open** is a register number */
#define OPFLAG_PERMUTE       0x01    /* OP_Compare: use the permutation */
#define OPFLAG_SAVEPOSITION  0x02    /* OP_Delete/Insert: save cursor pos */
#define OPFLAG_AUXDELETE     0x04    /* OP_Delete: index in a DELETE op */
#define OPFLAG_NOCHNG_MAGIC  0x6d    /* OP_MakeRecord: serialtype 10 is ok */
#define OPFLAG_PREFORMAT     0x80    /* OP_Insert uses preformatted cell */

/*
** Each trigger present in the database schema is stored as an instance of
** struct Trigger.
**
** Pointers to instances of struct Trigger are stored in two ways.
** 1. In the "trigHash" hash table (part of the sqlite3* that represents the
**    database). This allows Trigger structures to be retrieved by name.
** 2. All triggers associated with a single table form a linked list, using the
**    pNext member of struct Trigger. A pointer to the first element of the
**    linked list is stored as the "pTrigger" member of the associated
**    struct Table.
**
** The "step_list" member points to the first element of a linked list
** containing the SQL statements specified as the trigger program.
*/
struct Trigger {
  char *zName;            /* The name of the trigger                        */
  char *table;            /* The table or view to which the trigger applies */
  u8 op;                  /* One of TK_DELETE, TK_UPDATE, TK_INSERT         */
  u8 tr_tm;               /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
  u8 bReturning;          /* This trigger implements a RETURNING clause */
  Expr *pWhen;            /* The WHEN clause of the expression (may be NULL) */
  IdList *pColumns;       /* If this is an UPDATE OF  trigger,
                             the  is stored here */
  Schema *pSchema;        /* Schema containing the trigger */
  Schema *pTabSchema;     /* Schema containing the table */
  TriggerStep *step_list; /* Link list of trigger program steps             */
  Trigger *pNext;         /* Next trigger associated with the table */
};

/*
** A trigger is either a BEFORE or an AFTER trigger.  The following constants
** determine which.
**
** If there are multiple triggers, you might of some BEFORE and some AFTER.
** In that cases, the constants below can be ORed together.
*/
#define TRIGGER_BEFORE  1
#define TRIGGER_AFTER   2

/*
** An instance of struct TriggerStep is used to store a single SQL statement
** that is a part of a trigger-program.
**
** Instances of struct TriggerStep are stored in a singly linked list (linked
** using the "pNext" member) referenced by the "step_list" member of the
** associated struct Trigger instance. The first element of the linked list is
** the first step of the trigger-program.
**
** The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
** "SELECT" statement. The meanings of the other members is determined by the
** value of "op" as follows:
**
** (op == TK_INSERT)
** orconf    -> stores the ON CONFLICT algorithm
** pSelect   -> The content to be inserted - either a SELECT statement or
**              a VALUES clause.
** pSrc      -> Table to insert into.
** pIdList   -> If this is an INSERT INTO ... () VALUES ...
**              statement, then this stores the column-names to be
**              inserted into.
** pUpsert   -> The ON CONFLICT clauses for an Upsert
**
** (op == TK_DELETE)
** pSrc      -> Table to delete from
** pWhere    -> The WHERE clause of the DELETE statement if one is specified.
**              Otherwise NULL.
**
** (op == TK_UPDATE)
** pSrc      -> Table to update, followed by any FROM clause tables.
** pWhere    -> The WHERE clause of the UPDATE statement if one is specified.
**              Otherwise NULL.
** pExprList -> A list of the columns to update and the expressions to update
**              them to. See sqlite3Update() documentation of "pChanges"
**              argument.
**
** (op == TK_SELECT)
** pSelect   -> The SELECT statement
**
** (op == TK_RETURNING)
** pExprList -> The list of expressions that follow the RETURNING keyword.
**
*/
struct TriggerStep {
  u8 op;               /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT,
                       ** or TK_RETURNING */
  u8 orconf;           /* OE_Rollback etc. */
  Trigger *pTrig;      /* The trigger that this step is a part of */
  Select *pSelect;     /* SELECT statement or RHS of INSERT INTO SELECT ... */
  SrcList *pSrc;       /* Table to insert/update/delete */
  Expr *pWhere;        /* The WHERE clause for DELETE or UPDATE steps */
  ExprList *pExprList; /* SET clause for UPDATE, or RETURNING clause */
  IdList *pIdList;     /* Column names for INSERT */
  Upsert *pUpsert;     /* Upsert clauses on an INSERT */
  char *zSpan;         /* Original SQL text of this command */
  TriggerStep *pNext;  /* Next in the link-list */
  TriggerStep *pLast;  /* Last element in link-list. Valid for 1st elem only */
};

/*
** Information about a RETURNING clause
*/
struct Returning {
  Parse *pParse;        /* The parse that includes the RETURNING clause */
  ExprList *pReturnEL;  /* List of expressions to return */
  Trigger retTrig;      /* The transient trigger that implements RETURNING */
  TriggerStep retTStep; /* The trigger step */
  int iRetCur;          /* Transient table holding RETURNING results */
  int nRetCol;          /* Number of in pReturnEL after expansion */
  int iRetReg;          /* Register array for holding a row of RETURNING */
  char zName[40];       /* Name of trigger: "sqlite_returning_%p" */
};

/*
** An object used to accumulate the text of a string where we
** do not necessarily know how big the string will be in the end.
*/
struct sqlite3_str {
  sqlite3 *db;         /* Optional database for lookaside.  Can be NULL */
  char *zText;         /* The string collected so far */
  u32  nAlloc;         /* Amount of space allocated in zText */
  u32  mxAlloc;        /* Maximum allowed allocation.  0 for no malloc usage */
  u32  nChar;          /* Length of the string so far */
  u8   accError;       /* SQLITE_NOMEM or SQLITE_TOOBIG */
  u8   printfFlags;    /* SQLITE_PRINTF flags below */
};
#define SQLITE_PRINTF_INTERNAL 0x01  /* Internal-use-only converters allowed */
#define SQLITE_PRINTF_SQLFUNC  0x02  /* SQL function arguments to VXPrintf */
#define SQLITE_PRINTF_MALLOCED 0x04  /* True if zText is allocated space */

#define isMalloced(X)  (((X)->printfFlags & SQLITE_PRINTF_MALLOCED)!=0)

/*
** The following object is the header for an "RCStr" or "reference-counted
** string".  An RCStr is passed around and used like any other char*
** that has been dynamically allocated.  The important interface
** differences:
**
**   1.  RCStr strings are reference counted.  They are deallocated
**       when the reference count reaches zero.
**
**   2.  Use sqlite3RCStrUnref() to free an RCStr string rather than
**       sqlite3_free()
**
**   3.  Make a (read-only) copy of a read-only RCStr string using
**       sqlite3RCStrRef().
**
** "String" is in the name, but an RCStr object can also be used to hold
** binary data.
*/
struct RCStr {
  u64 nRCRef;            /* Number of references */
  /* Total structure size should be a multiple of 8 bytes for alignment */
};

/*
** A pointer to this structure is used to communicate information
** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
*/
typedef struct {
  sqlite3 *db;        /* The database being initialized */
  char **pzErrMsg;    /* Error message stored here */
  int iDb;            /* 0 for main database.  1 for TEMP, 2.. for ATTACHed */
  int rc;             /* Result code stored here */
  u32 mInitFlags;     /* Flags controlling error messages */
  u32 nInitRow;       /* Number of rows processed */
  Pgno mxPage;        /* Maximum page number.  0 for no limit. */
} InitData;

/*
** Allowed values for mInitFlags
*/
#define INITFLAG_AlterMask     0x0007  /* Types of ALTER */
#define INITFLAG_AlterRename   0x0001  /* Reparse after a RENAME */
#define INITFLAG_AlterDrop     0x0002  /* Reparse after a DROP COLUMN */
#define INITFLAG_AlterAdd      0x0003  /* Reparse after an ADD COLUMN */
#define INITFLAG_AlterDropCons 0x0004  /* Reparse after an ADD COLUMN */

/* Tuning parameters are set using SQLITE_TESTCTRL_TUNE and are controlled
** on debug-builds of the CLI using ".testctrl tune ID VALUE".  Tuning
** parameters are for temporary use during development, to help find
** optimal values for parameters in the query planner.  The should not
** be used on trunk check-ins.  They are a temporary mechanism available
** for transient development builds only.
**
** Tuning parameters are numbered starting with 1.
*/
#define SQLITE_NTUNE  6             /* Should be zero for all trunk check-ins */
#ifdef SQLITE_DEBUG
# define Tuning(X)  (sqlite3Config.aTune[(X)-1])
#else
# define Tuning(X)  0
#endif

/*
** Structure containing global configuration data for the SQLite library.
**
** This structure also contains some state information.
*/
struct Sqlite3Config {
  int bMemstat;                     /* True to enable memory status */
  u8 bCoreMutex;                    /* True to enable core mutexing */
  u8 bFullMutex;                    /* True to enable full mutexing */
  u8 bOpenUri;                      /* True to interpret filenames as URIs */
  u8 bUseCis;                       /* Use covering indices for full-scans */
  u8 bSmallMalloc;                  /* Avoid large memory allocations if true */
  u8 bExtraSchemaChecks;            /* Verify type,name,tbl_name in schema */
#ifdef SQLITE_DEBUG
  u8 bJsonSelfcheck;                /* Double-check JSON parsing */
#endif
  int mxStrlen;                     /* Maximum string length */
  int neverCorrupt;                 /* Database is always well-formed */
  int szLookaside;                  /* Default lookaside buffer size */
  int nLookaside;                   /* Default lookaside buffer count */
  int nStmtSpill;                   /* Stmt-journal spill-to-disk threshold */
  sqlite3_mem_methods m;            /* Low-level memory allocation interface */
  sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
  sqlite3_pcache_methods2 pcache2;  /* Low-level page-cache interface */
  void *pHeap;                      /* Heap storage space */
  int nHeap;                        /* Size of pHeap[] */
  int mnReq, mxReq;                 /* Min and max heap requests sizes */
  sqlite3_int64 szMmap;             /* mmap() space per open file */
  sqlite3_int64 mxMmap;             /* Maximum value for szMmap */
  void *pPage;                      /* Page cache memory */
  int szPage;                       /* Size of each page in pPage[] */
  int nPage;                        /* Number of pages in pPage[] */
  int mxParserStack;                /* maximum depth of the parser stack */
  int sharedCacheEnabled;           /* true if shared-cache mode enabled */
  u32 szPma;                        /* Maximum Sorter PMA size */
  /* The above might be initialized to non-zero.  The following need to always
  ** initially be zero, however. */
  int isInit;                       /* True after initialization has finished */
  int inProgress;                   /* True while initialization in progress */
  int isMutexInit;                  /* True after mutexes are initialized */
  int isMallocInit;                 /* True after malloc is initialized */
  int isPCacheInit;                 /* True after malloc is initialized */
  int nRefInitMutex;                /* Number of users of pInitMutex */
  sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
  void (*xLog)(void*,int,const char*); /* Function for logging */
  void *pLogArg;                       /* First argument to xLog() */
#ifdef SQLITE_ENABLE_SQLLOG
  void(*xSqllog)(void*,sqlite3*,const char*, int);
  void *pSqllogArg;
#endif
#ifdef SQLITE_VDBE_COVERAGE
  /* The following callback (if not NULL) is invoked on every VDBE branch
  ** operation.  Set the callback using SQLITE_TESTCTRL_VDBE_COVERAGE.
  */
  void (*xVdbeBranch)(void*,unsigned iSrcLine,u8 eThis,u8 eMx);  /* Callback */
  void *pVdbeBranchArg;                                     /* 1st argument */
#endif
#ifndef SQLITE_OMIT_DESERIALIZE
  sqlite3_int64 mxMemdbSize;        /* Default max memdb size */
#endif
#ifndef SQLITE_UNTESTABLE
  int (*xTestCallback)(int);        /* Invoked by sqlite3FaultSim() */
#endif
#ifdef SQLITE_ALLOW_ROWID_IN_VIEW
  u32 mNoVisibleRowid;              /* TF_NoVisibleRowid if the ROWID_IN_VIEW
                                    ** feature is disabled.  0 if rowids can
                                    ** occur in views. */
#endif
  int bLocaltimeFault;              /* True to fail localtime() calls */
  int (*xAltLocaltime)(const void*,void*); /* Alternative localtime() routine */
  int iOnceResetThreshold;          /* When to reset OP_Once counters */
  u32 szSorterRef;                  /* Min size in bytes to use sorter-refs */
  unsigned int iPrngSeed;           /* Alternative fixed seed for the PRNG */
  /* vvvv--- must be last ---vvv */
#ifdef SQLITE_DEBUG
  sqlite3_int64 aTune[SQLITE_NTUNE]; /* Tuning parameters */
#endif
};

/*
** This macro is used inside of assert() statements to indicate that
** the assert is only valid on a well-formed database.  Instead of:
**
**     assert( X );
**
** One writes:
**
**     assert( X || CORRUPT_DB );
**
** CORRUPT_DB is true during normal operation.  CORRUPT_DB does not indicate
** that the database is definitely corrupt, only that it might be corrupt.
** For most test cases, CORRUPT_DB is set to false using a special
** sqlite3_test_control().  This enables assert() statements to prove
** things that are always true for well-formed databases.
*/
#define CORRUPT_DB  (sqlite3Config.neverCorrupt==0)

/*
** Context pointer passed down through the tree-walk.
*/
struct Walker {
  Parse *pParse;                            /* Parser context.  */
  int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
  int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
  void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
  int walkerDepth;                          /* Number of subqueries */
  u16 eCode;                                /* A small processing code */
  u16 mWFlags;                              /* Use-dependent flags */
  union {                                   /* Extra data for callback */
    NameContext *pNC;                         /* Naming context */
    int n;                                    /* A counter */
    int iCur;                                 /* A cursor number */
    int sz;                                   /* String literal length */
    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() */
    Mem *aMem;                                /* See sqlite3BtreeCursorHint() */
    struct CheckOnCtx *pCheckOnCtx;           /* See selectCheckOnClauses() */
  } u;
};

/*
** The following structure contains information used by the sqliteFix...
** routines as they walk the parse tree to make database references
** explicit.
*/
struct DbFixer {
  Parse *pParse;      /* The parsing context.  Error messages written here */
  Walker w;           /* Walker object */
  Schema *pSchema;    /* Fix items to this schema */
  u8 bTemp;           /* True for TEMP schema entries */
  const char *zDb;    /* Make sure all objects are contained in this database */
  const char *zType;  /* Type of the container - used for error messages */
  const Token *pName; /* Name of the container - used for error messages */
};

/* Forward declarations */
int sqlite3WalkExpr(Walker*, Expr*);
int sqlite3WalkExprNN(Walker*, Expr*);
int sqlite3WalkExprList(Walker*, ExprList*);
int sqlite3WalkSelect(Walker*, Select*);
int sqlite3WalkSelectExpr(Walker*, Select*);
int sqlite3WalkSelectFrom(Walker*, Select*);
int sqlite3ExprWalkNoop(Walker*, Expr*);
int sqlite3SelectWalkNoop(Walker*, Select*);
int sqlite3SelectWalkFail(Walker*, Select*);
int sqlite3WalkerDepthIncrease(Walker*,Select*);
void sqlite3WalkerDepthDecrease(Walker*,Select*);
void sqlite3WalkWinDefnDummyCallback(Walker*,Select*);

#ifdef SQLITE_DEBUG
void sqlite3SelectWalkAssert2(Walker*, Select*);
#endif

#ifndef SQLITE_OMIT_CTE
void sqlite3SelectPopWith(Walker*, Select*);
#else
# define sqlite3SelectPopWith 0
#endif

/*
** Return code from the parse-tree walking primitives and their
** callbacks.
*/
#define WRC_Continue    0   /* Continue down into children */
#define WRC_Prune       1   /* Omit children but continue walking siblings */
#define WRC_Abort       2   /* Abandon the tree walk */

/*
** A single common table expression
*/
struct Cte {
  char *zName;            /* Name of this CTE */
  ExprList *pCols;        /* List of explicit column names, or NULL */
  Select *pSelect;        /* The definition of this CTE */
  const char *zCteErr;    /* Error message for circular references */
  CteUse *pUse;           /* Usage information for this CTE */
  u8 eM10d;               /* The MATERIALIZED flag */
};

/*
** Allowed values for the materialized flag (eM10d):
*/
#define M10d_Yes       0  /* AS MATERIALIZED */
#define M10d_Any       1  /* Not specified.  Query planner's choice */
#define M10d_No        2  /* AS NOT MATERIALIZED */

/*
** An instance of the With object represents a WITH clause containing
** one or more CTEs (common table expressions).
*/
struct With {
  int nCte;               /* Number of CTEs in the WITH clause */
  int bView;              /* Belongs to the outermost Select of a view */
  With *pOuter;           /* Containing WITH clause, or NULL */
  Cte a[FLEXARRAY];       /* For each CTE in the WITH clause.... */
};

/* The size (in bytes) of a With object that can hold as many
** as N different CTEs. */
#define SZ_WITH(N)  (offsetof(With,a) + (N)*sizeof(Cte))

/*
** The Cte object is not guaranteed to persist for the entire duration
** of code generation.  (The query flattener or other parser tree
** edits might delete it.)  The following object records information
** about each Common Table Expression that must be preserved for the
** duration of the parse.
**
** The CteUse objects are freed using sqlite3ParserAddCleanup() rather
** than sqlite3SelectDelete(), which is what enables them to persist
** until the end of code generation.
*/
struct CteUse {
  int nUse;              /* Number of users of this CTE */
  int addrM9e;           /* Start of subroutine to compute materialization */
  int regRtn;            /* Return address register for addrM9e subroutine */
  int iCur;              /* Ephemeral table holding the materialization */
  LogEst nRowEst;        /* Estimated number of rows in the table */
  u8 eM10d;              /* The MATERIALIZED flag */
};


/* Client data associated with sqlite3_set_clientdata() and
** sqlite3_get_clientdata().
*/
struct DbClientData {
  DbClientData *pNext;        /* Next in a linked list */
  void *pData;                /* The data */
  void (*xDestructor)(void*); /* Destructor.  Might be NULL */
  char zName[FLEXARRAY];      /* Name of this client data. MUST BE LAST */
};

/* The size (in bytes) of a DbClientData object that can has a name
** that is N bytes long, including the zero-terminator. */
#define SZ_DBCLIENTDATA(N) (offsetof(DbClientData,zName)+(N))

#ifdef SQLITE_DEBUG
/*
** An instance of the TreeView object is used for printing the content of
** data structures on sqlite3DebugPrintf() using a tree-like view.
*/
struct TreeView {
  int iLevel;             /* Which level of the tree we are on */
  u8  bLine[100];         /* Draw vertical in column i if bLine[i] is true */
};
#endif /* SQLITE_DEBUG */

/*
** This object is used in various ways, most (but not all) related to window
** functions.
**
**   (1) A single instance of this structure is attached to the
**       the Expr.y.pWin field for each window function in an expression tree.
**       This object holds the information contained in the OVER clause,
**       plus additional fields used during code generation.
**
**   (2) All window functions in a single SELECT form a linked-list
**       attached to Select.pWin.  The Window.pFunc and Window.pExpr
**       fields point back to the expression that is the window function.
**
**   (3) The terms of the WINDOW clause of a SELECT are instances of this
**       object on a linked list attached to Select.pWinDefn.
**
**   (4) For an aggregate function with a FILTER clause, an instance
**       of this object is stored in Expr.y.pWin with eFrmType set to
**       TK_FILTER. In this case the only field used is Window.pFilter.
**
** The uses (1) and (2) are really the same Window object that just happens
** to be accessible in two different ways.  Use case (3) are separate objects.
*/
struct Window {
  char *zName;            /* Name of window (may be NULL) */
  char *zBase;            /* Name of base window for chaining (may be NULL) */
  ExprList *pPartition;   /* PARTITION BY clause */
  ExprList *pOrderBy;     /* ORDER BY clause */
  u8 eFrmType;            /* TK_RANGE, TK_GROUPS, TK_ROWS, or 0 */
  u8 eStart;              /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
  u8 eEnd;                /* UNBOUNDED, CURRENT, PRECEDING or FOLLOWING */
  u8 bImplicitFrame;      /* True if frame was implicitly specified */
  u8 eExclude;            /* TK_NO, TK_CURRENT, TK_TIES, TK_GROUP, or 0 */
  Expr *pStart;           /* Expression for " PRECEDING" */
  Expr *pEnd;             /* Expression for " FOLLOWING" */
  Window **ppThis;        /* Pointer to this object in Select.pWin list */
  Window *pNextWin;       /* Next window function belonging to this SELECT */
  Expr *pFilter;          /* The FILTER expression */
  FuncDef *pWFunc;        /* The function */
  int iEphCsr;            /* Partition buffer or Peer buffer */
  int regAccum;           /* Accumulator */
  int regResult;          /* Interim result */
  int csrApp;             /* Function cursor (used by min/max) */
  int regApp;             /* Function register (also used by min/max) */
  int regPart;            /* Array of registers for PARTITION BY values */
  Expr *pOwner;           /* Expression object this window is attached to */
  int nBufferCol;         /* Number of columns in buffer table */
  int iArgCol;            /* Offset of first argument for this function */
  int regOne;             /* Register containing constant value 1 */
  int regStartRowid;
  int regEndRowid;
  u8 bExprArgs;           /* Defer evaluation of window function arguments
                          ** due to the SQLITE_SUBTYPE flag */
};

Select *sqlite3MultiValues(Parse *pParse, Select *pLeft, ExprList *pRow);
void sqlite3MultiValuesEnd(Parse *pParse, Select *pVal);

#ifndef SQLITE_OMIT_WINDOWFUNC
void sqlite3WindowDelete(sqlite3*, Window*);
void sqlite3WindowUnlinkFromSelect(Window*);
void sqlite3WindowListDelete(sqlite3 *db, Window *p);
Window *sqlite3WindowAlloc(Parse*, int, int, Expr*, int , Expr*, u8);
void sqlite3WindowAttach(Parse*, Expr*, Window*);
void sqlite3WindowLink(Select *pSel, Window *pWin);
int sqlite3WindowCompare(const Parse*, const Window*, const Window*, int);
void sqlite3WindowCodeInit(Parse*, Select*);
void sqlite3WindowCodeStep(Parse*, Select*, WhereInfo*, int, int);
int sqlite3WindowRewrite(Parse*, Select*);
void sqlite3WindowUpdate(Parse*, Window*, Window*, FuncDef*);
Window *sqlite3WindowDup(sqlite3 *db, Expr *pOwner, Window *p);
Window *sqlite3WindowListDup(sqlite3 *db, Window *p);
void sqlite3WindowFunctions(void);
void sqlite3WindowChain(Parse*, Window*, Window*);
Window *sqlite3WindowAssemble(Parse*, Window*, ExprList*, ExprList*, Token*);
#else
# define sqlite3WindowDelete(a,b)
# define sqlite3WindowFunctions()
# define sqlite3WindowAttach(a,b,c)
#endif

/*
** Assuming zIn points to the first byte of a UTF-8 character,
** advance zIn to point to the first byte of the next UTF-8 character.
*/
#define SQLITE_SKIP_UTF8(zIn) {                        \
  if( (*(zIn++))>=0xc0 ){                              \
    while( (*zIn & 0xc0)==0x80 ){ zIn++; }             \
  }                                                    \
}

/*
** The SQLITE_*_BKPT macros are substitutes for the error codes with
** the same name but without the _BKPT suffix.  These macros invoke
** routines that report the line-number on which the error originated
** using sqlite3_log().  The routines also provide a convenient place
** to set a debugger breakpoint.
*/
int sqlite3ReportError(int iErr, int lineno, const char *zType);
int sqlite3CorruptError(int);
int sqlite3MisuseError(int);
int sqlite3CantopenError(int);
#define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
#define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
#define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
#ifdef SQLITE_DEBUG
  int sqlite3NomemError(int);
  int sqlite3IoerrnomemError(int);
# define SQLITE_NOMEM_BKPT sqlite3NomemError(__LINE__)
# define SQLITE_IOERR_NOMEM_BKPT sqlite3IoerrnomemError(__LINE__)
#else
# define SQLITE_NOMEM_BKPT SQLITE_NOMEM
# define SQLITE_IOERR_NOMEM_BKPT SQLITE_IOERR_NOMEM
#endif
#if defined(SQLITE_DEBUG) || defined(SQLITE_ENABLE_CORRUPT_PGNO)
  int sqlite3CorruptPgnoError(int,Pgno);
# define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptPgnoError(__LINE__,(P))
#else
# define SQLITE_CORRUPT_PGNO(P) sqlite3CorruptError(__LINE__)
#endif

/*
** FTS3 and FTS4 both require virtual table support
*/
#if defined(SQLITE_OMIT_VIRTUALTABLE)
# undef SQLITE_ENABLE_FTS3
# undef SQLITE_ENABLE_FTS4
#endif

/*
** FTS4 is really an extension for FTS3.  It is enabled using the
** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also call
** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
*/
#if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
# define SQLITE_ENABLE_FTS3 1
#endif

/*
** The following macros mimic the standard library functions toupper(),
** isspace(), isalnum(), isdigit() and isxdigit(), respectively. The
** sqlite versions only work for ASCII characters, regardless of locale.
*/
#ifdef SQLITE_ASCII
# define sqlite3Toupper(x)  ((x)&~(sqlite3CtypeMap[(unsigned char)(x)]&0x20))
# define sqlite3Isspace(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x01)
# define sqlite3Isalnum(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x06)
# define sqlite3Isalpha(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x02)
# define sqlite3Isdigit(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x04)
# define sqlite3Isxdigit(x)  (sqlite3CtypeMap[(unsigned char)(x)]&0x08)
# define sqlite3Tolower(x)   (sqlite3UpperToLower[(unsigned char)(x)])
# define sqlite3Isquote(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x80)
# define sqlite3JsonId1(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x42)
# define sqlite3JsonId2(x)   (sqlite3CtypeMap[(unsigned char)(x)]&0x46)
#else
# define sqlite3Toupper(x)   toupper((unsigned char)(x))
# define sqlite3Isspace(x)   isspace((unsigned char)(x))
# define sqlite3Isalnum(x)   isalnum((unsigned char)(x))
# define sqlite3Isalpha(x)   isalpha((unsigned char)(x))
# define sqlite3Isdigit(x)   isdigit((unsigned char)(x))
# define sqlite3Isxdigit(x)  isxdigit((unsigned char)(x))
# define sqlite3Tolower(x)   tolower((unsigned char)(x))
# define sqlite3Isquote(x)   ((x)=='"'||(x)=='\''||(x)=='['||(x)=='`')
# define sqlite3JsonId1(x)   (sqlite3IsIdChar(x)&&(x)0 && (db)->aVTrans==0)
#endif
int sqlite3ReadOnlyShadowTables(sqlite3 *db);
#ifndef SQLITE_OMIT_VIRTUALTABLE
  int sqlite3ShadowTableName(sqlite3 *db, const char *zName);
  int sqlite3IsShadowTableOf(sqlite3*,Table*,const char*);
  void sqlite3MarkAllShadowTablesOf(sqlite3*, Table*);
#else
# define sqlite3ShadowTableName(A,B) 0
# define sqlite3IsShadowTableOf(A,B,C) 0
# define sqlite3MarkAllShadowTablesOf(A,B)
#endif
int sqlite3VtabEponymousTableInit(Parse*,Module*);
void sqlite3VtabEponymousTableClear(sqlite3*,Module*);
void sqlite3VtabMakeWritable(Parse*,Table*);
void sqlite3VtabBeginParse(Parse*, Token*, Token*, Token*, int);
void sqlite3VtabFinishParse(Parse*, Token*);
void sqlite3VtabArgInit(Parse*);
void sqlite3VtabArgExtend(Parse*, Token*);
int sqlite3VtabCallCreate(sqlite3*, int, const char *, char **);
int sqlite3VtabCallConnect(Parse*, Table*);
int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
int sqlite3VtabBegin(sqlite3 *, VTable *);

FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
void sqlite3VtabUsesAllSchemas(Parse*);
sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
void sqlite3ParseObjectInit(Parse*,sqlite3*);
void sqlite3ParseObjectReset(Parse*);
void *sqlite3ParserAddCleanup(Parse*,void(*)(sqlite3*,void*),void*);
#ifdef SQLITE_ENABLE_NORMALIZE
char *sqlite3Normalize(Vdbe*, const char*);
#endif
int sqlite3Reprepare(Vdbe*);
void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
CollSeq *sqlite3ExprCompareCollSeq(Parse*,const Expr*);
CollSeq *sqlite3BinaryCompareCollSeq(Parse *, const Expr*, const Expr*);
int sqlite3TempInMemory(const sqlite3*);
const char *sqlite3JournalModename(int);
#ifndef SQLITE_OMIT_WAL
  int sqlite3Checkpoint(sqlite3*, int, int, int*, int*);
  int sqlite3WalDefaultHook(void*,sqlite3*,const char*,int);
#endif
#ifndef SQLITE_OMIT_CTE
  Cte *sqlite3CteNew(Parse*,Token*,ExprList*,Select*,u8);
  void sqlite3CteDelete(sqlite3*,Cte*);
  With *sqlite3WithAdd(Parse*,With*,Cte*);
  void sqlite3WithDelete(sqlite3*,With*);
  void sqlite3WithDeleteGeneric(sqlite3*,void*);
  With *sqlite3WithPush(Parse*, With*, u8);
#else
# define sqlite3CteNew(P,T,E,S)   ((void*)0)
# define sqlite3CteDelete(D,C)
# define sqlite3CteWithAdd(P,W,C) ((void*)0)
# define sqlite3WithDelete(x,y)
# define sqlite3WithPush(x,y,z) ((void*)0)
#endif
#ifndef SQLITE_OMIT_UPSERT
  Upsert *sqlite3UpsertNew(sqlite3*,ExprList*,Expr*,ExprList*,Expr*,Upsert*);
  void sqlite3UpsertDelete(sqlite3*,Upsert*);
  Upsert *sqlite3UpsertDup(sqlite3*,Upsert*);
  int sqlite3UpsertAnalyzeTarget(Parse*,SrcList*,Upsert*,Upsert*);
  void sqlite3UpsertDoUpdate(Parse*,Upsert*,Table*,Index*,int);
  Upsert *sqlite3UpsertOfIndex(Upsert*,Index*);
  int sqlite3UpsertNextIsIPK(Upsert*);
#else
#define sqlite3UpsertNew(u,v,w,x,y,z) ((Upsert*)0)
#define sqlite3UpsertDelete(x,y)
#define sqlite3UpsertDup(x,y)         ((Upsert*)0)
#define sqlite3UpsertOfIndex(x,y)     ((Upsert*)0)
#define sqlite3UpsertNextIsIPK(x)     0
#endif


/* Declarations for functions in fkey.c. All of these are replaced by
** no-op macros if OMIT_FOREIGN_KEY is defined. In this case no foreign
** key functionality is available. If OMIT_TRIGGER is defined but
** OMIT_FOREIGN_KEY is not, only some of the functions are no-oped. In
** this case foreign keys are parsed, but no other functionality is
** provided (enforcement of FK constraints requires the triggers sub-system).
*/
#if !defined(SQLITE_OMIT_FOREIGN_KEY) && !defined(SQLITE_OMIT_TRIGGER)
  void sqlite3FkCheck(Parse*, Table*, int, int, int*, int);
  void sqlite3FkDropTable(Parse*, SrcList *, Table*);
  void sqlite3FkActions(Parse*, Table*, ExprList*, int, int*, int);
  int sqlite3FkRequired(Parse*, Table*, int*, int);
  u32 sqlite3FkOldmask(Parse*, Table*);
  FKey *sqlite3FkReferences(Table *);
  void sqlite3FkClearTriggerCache(sqlite3*,int);
#else
  #define sqlite3FkActions(a,b,c,d,e,f)
  #define sqlite3FkCheck(a,b,c,d,e,f)
  #define sqlite3FkDropTable(a,b,c)
  #define sqlite3FkOldmask(a,b)         0
  #define sqlite3FkRequired(a,b,c,d)    0
  #define sqlite3FkReferences(a)        0
  #define sqlite3FkClearTriggerCache(a,b)
#endif
#ifndef SQLITE_OMIT_FOREIGN_KEY
  void sqlite3FkDelete(sqlite3 *, Table*);
  int sqlite3FkLocateIndex(Parse*,Table*,FKey*,Index**,int**);
#else
  #define sqlite3FkDelete(a,b)
  #define sqlite3FkLocateIndex(a,b,c,d,e)
#endif


/*
** Available fault injectors.  Should be numbered beginning with 0.
*/
#define SQLITE_FAULTINJECTOR_MALLOC     0
#define SQLITE_FAULTINJECTOR_COUNT      1

/*
** The interface to the code in fault.c used for identifying "benign"
** malloc failures. This is only present if SQLITE_UNTESTABLE
** is not defined.
*/
#ifndef SQLITE_UNTESTABLE
  void sqlite3BeginBenignMalloc(void);
  void sqlite3EndBenignMalloc(void);
#else
  #define sqlite3BeginBenignMalloc()
  #define sqlite3EndBenignMalloc()
#endif

/*
** Allowed return values from sqlite3FindInIndex()
*/
#define IN_INDEX_ROWID        1   /* Search the rowid of the table */
#define IN_INDEX_EPH          2   /* Search an ephemeral b-tree */
#define IN_INDEX_INDEX_ASC    3   /* Existing index ASCENDING */
#define IN_INDEX_INDEX_DESC   4   /* Existing index DESCENDING */
#define IN_INDEX_NOOP         5   /* No table available. Use comparisons */
/*
** Allowed flags for the 3rd parameter to sqlite3FindInIndex().
*/
#define IN_INDEX_NOOP_OK     0x0001  /* OK to return IN_INDEX_NOOP */
#define IN_INDEX_MEMBERSHIP  0x0002  /* IN operator used for membership test */
#define IN_INDEX_LOOP        0x0004  /* IN operator used as a loop */
int sqlite3FindInIndex(Parse *, Expr *, u32, int*, int*, int*);

int sqlite3JournalOpen(sqlite3_vfs *, const char *, sqlite3_file *, int, int);
int sqlite3JournalSize(sqlite3_vfs *);
#if defined(SQLITE_ENABLE_ATOMIC_WRITE) \
 || defined(SQLITE_ENABLE_BATCH_ATOMIC_WRITE)
  int sqlite3JournalCreate(sqlite3_file *);
#endif

int sqlite3JournalIsInMemory(sqlite3_file *p);
void sqlite3MemJournalOpen(sqlite3_file *);

void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p);
#if SQLITE_MAX_EXPR_DEPTH>0
  int sqlite3SelectExprHeight(const Select *);
  int sqlite3ExprCheckHeight(Parse*, int);
#else
  #define sqlite3SelectExprHeight(x) 0
  #define sqlite3ExprCheckHeight(x,y)
#endif
void sqlite3ExprSetErrorOffset(Expr*,int);

u32 sqlite3Get4byte(const u8*);
void sqlite3Put4byte(u8*, u32);

#ifdef SQLITE_ENABLE_UNLOCK_NOTIFY
  void sqlite3ConnectionBlocked(sqlite3 *, sqlite3 *);
  void sqlite3ConnectionUnlocked(sqlite3 *db);
  void sqlite3ConnectionClosed(sqlite3 *db);
#else
  #define sqlite3ConnectionBlocked(x,y)
  #define sqlite3ConnectionUnlocked(x)
  #define sqlite3ConnectionClosed(x)
#endif

#ifdef SQLITE_DEBUG
  void sqlite3ParserTrace(FILE*, char *);
#endif
#if defined(YYCOVERAGE)
  int sqlite3ParserCoverage(FILE*);
#endif

/*
** If the SQLITE_ENABLE IOTRACE exists then the global variable
** sqlite3IoTrace is a pointer to a printf-like routine used to
** print I/O tracing messages.
*/
#ifdef SQLITE_ENABLE_IOTRACE
# define IOTRACE(A)  if( sqlite3IoTrace ){ sqlite3IoTrace A; }
  void sqlite3VdbeIOTraceSql(Vdbe*);
SQLITE_API SQLITE_EXTERN void (SQLITE_CDECL *sqlite3IoTrace)(const char*,...);
#else
# define IOTRACE(A)
# define sqlite3VdbeIOTraceSql(X)
#endif

/*
** These routines are available for the mem2.c debugging memory allocator
** only.  They are used to verify that different "types" of memory
** allocations are properly tracked by the system.
**
** sqlite3MemdebugSetType() sets the "type" of an allocation to one of
** the MEMTYPE_* macros defined below.  The type must be a bitmask with
** a single bit set.
**
** sqlite3MemdebugHasType() returns true if any of the bits in its second
** argument match the type set by the previous sqlite3MemdebugSetType().
** sqlite3MemdebugHasType() is intended for use inside assert() statements.
**
** sqlite3MemdebugNoType() returns true if none of the bits in its second
** argument match the type set by the previous sqlite3MemdebugSetType().
**
** Perhaps the most important point is the difference between MEMTYPE_HEAP
** and MEMTYPE_LOOKASIDE.  If an allocation is MEMTYPE_LOOKASIDE, that means
** it might have been allocated by lookaside, except the allocation was
** too large or lookaside was already full.  It is important to verify
** that allocations that might have been satisfied by lookaside are not
** passed back to non-lookaside free() routines.  Asserts such as the
** example above are placed on the non-lookaside free() routines to verify
** this constraint.
**
** All of this is no-op for a production build.  It only comes into
** play when the SQLITE_MEMDEBUG compile-time option is used.
*/
#ifdef SQLITE_MEMDEBUG
  void sqlite3MemdebugSetType(void*,u8);
  int sqlite3MemdebugHasType(const void*,u8);
  int sqlite3MemdebugNoType(const void*,u8);
#else
# define sqlite3MemdebugSetType(X,Y)  /* no-op */
# define sqlite3MemdebugHasType(X,Y)  1
# define sqlite3MemdebugNoType(X,Y)   1
#endif
#define MEMTYPE_HEAP       0x01  /* General heap allocations */
#define MEMTYPE_LOOKASIDE  0x02  /* Heap that might have been lookaside */
#define MEMTYPE_PCACHE     0x04  /* Page cache allocations */

/*
** Threading interface
*/
#if SQLITE_MAX_WORKER_THREADS>0
int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
int sqlite3ThreadJoin(SQLiteThread*, void**);
#endif

#if defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)
int sqlite3DbpageRegister(sqlite3*);
#endif
#if defined(SQLITE_ENABLE_DBSTAT_VTAB) || defined(SQLITE_TEST)
int sqlite3DbstatRegister(sqlite3*);
#endif

int sqlite3ExprVectorSize(const Expr *pExpr);
int sqlite3ExprIsVector(const Expr *pExpr);
Expr *sqlite3VectorFieldSubexpr(Expr*, int);
Expr *sqlite3ExprForVectorField(Parse*,Expr*,int,int);
void sqlite3VectorErrorMsg(Parse*, Expr*);

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

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

#if defined(VDBE_PROFILE) \
 || defined(SQLITE_PERFORMANCE_TRACE) \
 || defined(SQLITE_ENABLE_STMT_SCANSTATUS)
sqlite3_uint64 sqlite3Hwtime(void);
#endif

#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
# define IS_STMT_SCANSTATUS(db) (db->flags & SQLITE_StmtScanStatus)
#else
# define IS_STMT_SCANSTATUS(db) 0
#endif

#endif /* SQLITEINT_H */

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