/*
** If g.argv[arg] exists then it is either the name of a repository
** that will be used by a server, or else it is a directory that
** contains multiple repositories that can be served.  If g.argv[arg]
** is a directory, the repositories it contains must be named
** "*.fossil".  If g.argv[arg] does not exist, then we must be within
** an open check-out and the repository to serve is the repository of
** that check-out.
**
** Open the repository to be served if it is known.  If g.argv[arg] is
** a directory full of repositories, then set g.zRepositoryName to
** the name of that directory and the specific repository will be
** opened later by process_one_web_page() based on the content of
** the PATH_INFO variable.

static void shellModuleSchema(
  sqlite3_context *pCtx,
  int nVal,
  sqlite3_value **apVal
){
  const char *zName = (const char*)sqlite3_value_text(apVal[0]);
  char *zFake = shellFakeSchema(sqlite3_context_db_handle(pCtx), 0, zName);
  UNUSED_PARAMETER(nVal);
  if( zFake ){
    sqlite3_result_text(pCtx, sqlite3_mprintf("/* %s */", zFake),
                        -1, sqlite3_free);
    free(zFake);
  }
}

     "VIRTUAL TABLE"
  };
  int i = 0;
  const char *zIn = (const char*)sqlite3_value_text(apVal[0]);
  const char *zSchema = (const char*)sqlite3_value_text(apVal[1]);
  const char *zName = (const char*)sqlite3_value_text(apVal[2]);
  sqlite3 *db = sqlite3_context_db_handle(pCtx);
  UNUSED_PARAMETER(nVal);
  if( zIn!=0 && strncmp(zIn, "CREATE ", 7)==0 ){
    for(i=0; i<(int)(sizeof(aPrefix)/sizeof(aPrefix[0])); i++){
      int n = strlen30(aPrefix[i]);
      if( strncmp(zIn+7, aPrefix[i], n)==0 && zIn[n+7]==' ' ){
        char *z = 0;
        char *zFake = 0;
        if( zSchema ){

  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  int i;
  int iMode = sqlite3_value_int(argv[0]);
  char z[16];
  (void)argc;
  if( S_ISLNK(iMode) ){
    z[0] = 'l';
  }else if( S_ISREG(iMode) ){
    z[0] = '-';
  }else if( S_ISDIR(iMode) ){
    z[0] = 'd';
  }else{

  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  fsdir_tab *pNew = 0;
  int rc;
  (void)pAux;
  (void)argc;
  (void)argv;
  (void)pzErr;
  rc = sqlite3_declare_vtab(db, "CREATE TABLE x" FSDIR_SCHEMA);
  if( rc==SQLITE_OK ){
    pNew = (fsdir_tab*)sqlite3_malloc( sizeof(*pNew) );
    if( pNew==0 ) return SQLITE_NOMEM;
    memset(pNew, 0, sizeof(*pNew));
  }
  *ppVtab = (sqlite3_vtab*)pNew;

}

/*
** Constructor for a new fsdir_cursor object.
*/
static int fsdirOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
  fsdir_cursor *pCur;
  (void)p;
  pCur = sqlite3_malloc( sizeof(*pCur) );
  if( pCur==0 ) return SQLITE_NOMEM;
  memset(pCur, 0, sizeof(*pCur));
  pCur->iLvl = -1;
  *ppCursor = &pCur->base;
  return SQLITE_OK;
}

static int fsdirFilter(
  sqlite3_vtab_cursor *cur, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  const char *zDir = 0;
  fsdir_cursor *pCur = (fsdir_cursor*)cur;
  (void)idxStr;
  fsdirResetCursor(pCur);

  if( idxNum==0 ){
    fsdirSetErrmsg(pCur, "table function fsdir requires an argument");
    return SQLITE_ERROR;
  }

static int fsdirBestIndex(
  sqlite3_vtab *tab,
  sqlite3_index_info *pIdxInfo
){
  int i;                 /* Loop over constraints */
  int idx4 = -1;
  int idx5 = -1;

  const struct sqlite3_index_constraint *pConstraint;

  (void)tab;
  pConstraint = pIdxInfo->aConstraint;
  for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
    if( pConstraint->usable==0 ) continue;
    if( pConstraint->op!=SQLITE_INDEX_CONSTRAINT_EQ ) continue;
    if( pConstraint->iColumn==4 ) idx4 = i;
    if( pConstraint->iColumn==5 ) idx5 = i;
  }

    0,                         /* xUpdate */
    0,                         /* xBegin */
    0,                         /* xSync */
    0,                         /* xCommit */
    0,                         /* xRollback */
    0,                         /* xFindMethod */
    0,                         /* xRename */
    0,                         /* xSavepoint */
    0,                         /* xRelease */
    0                          /* xRollbackTo */
  };

  int rc = sqlite3_create_module(db, "fsdir", &fsdirModule, 0);
  return rc;
}
#else         /* SQLITE_OMIT_VIRTUALTABLE */
# define fsdirRegister(x) SQLITE_OK

  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  sqlite3_vfs *pOrig;
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;
  (void)db;
  pOrig = sqlite3_vfs_find(0);
  apnd_vfs.iVersion = pOrig->iVersion;
  apnd_vfs.pAppData = pOrig;
  apnd_vfs.szOsFile = pOrig->szOsFile + sizeof(ApndFile);
  rc = sqlite3_vfs_register(&apnd_vfs, 0);
#ifdef APPENDVFS_TEST
  if( rc==SQLITE_OK ){

  aOut = (u8*)sqlite3_malloc(nAlloc);
  if( aOut==0 ){
    rc = SQLITE_NOMEM;
  }else{
    int res;
    z_stream str;
    memset(&str, 0, sizeof(str));
    str.next_in = (Bytef*)aIn;
    str.avail_in = nIn;
    str.next_out = aOut;
    str.avail_out = nAlloc;

    deflateInit2(&str, 9, Z_DEFLATED, -15, 8, Z_DEFAULT_STRATEGY);
    res = deflate(&str, Z_FINISH);

      iMethod = sqlite3_value_int(apVal[8]);
      sz = nIn;
      pData = aIn;
      nData = nIn;
      if( iMethod!=0 && iMethod!=8 ){
        rc = SQLITE_CONSTRAINT;
      }else{
        if( bAuto || iMethod ){
          int nCmp;
          rc = zipfileDeflate(pTab, aIn, nIn, &pFree, &nCmp);
          if( rc==SQLITE_OK ){
            if( iMethod || nCmp<nIn ){
              iMethod = 8;
              pData = pFree;
              nData = nCmp;
            }
          }
        }
        iCrc32 = crc32(0, aIn, nIn);
      }
    }
  }

static int expertUpdate(
  sqlite3_vtab *pVtab, 
  int nData, 
  sqlite3_value **azData, 
  sqlite_int64 *pRowid
){
  (void)pVtab;
  (void)nData;
  (void)azData;
  (void)pRowid;
  return SQLITE_OK;
}

/* 
** Virtual table module xOpen method.
*/
static int expertOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  int rc = SQLITE_OK;
  ExpertCsr *pCsr;
  (void)pVTab;
  pCsr = idxMalloc(&rc, sizeof(ExpertCsr));
  *ppCursor = (sqlite3_vtab_cursor*)pCsr;
  return rc;
}

/* 
** Virtual table module xClose method.

  return rc;
}

/* 
** Virtual table module xRowid method.
*/
static int expertRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
  (void)cur;
  *pRowid = 0;
  return SQLITE_OK;
}

/* 
** Virtual table module xColumn method.
*/

  int argc, sqlite3_value **argv
){
  ExpertCsr *pCsr = (ExpertCsr*)cur;
  ExpertVtab *pVtab = (ExpertVtab*)(cur->pVtab);
  sqlite3expert *pExpert = pVtab->pExpert;
  int rc;

  (void)idxNum;
  (void)idxStr;
  (void)argc;
  (void)argv;
  rc = sqlite3_finalize(pCsr->pData);
  pCsr->pData = 0;
  if( rc==SQLITE_OK ){
    rc = idxPrintfPrepareStmt(pExpert->db, &pCsr->pData, &pVtab->base.zErrMsg,
        "SELECT * FROM main.%Q WHERE sample()", pVtab->pTab->zName
    );
  }

  return rc;
}

/*
** Create candidate indexes in database [dbm] based on the data in 
** linked-list pScan.
*/
static int idxCreateCandidates(sqlite3expert *p){
  int rc = SQLITE_OK;
  IdxScan *pIter;

  for(pIter=p->pScan; pIter && rc==SQLITE_OK; pIter=pIter->pNextScan){
    rc = idxCreateFromWhere(p, pIter, 0);
    if( rc==SQLITE_OK && pIter->pOrder ){
      rc = idxCreateFromWhere(p, pIter, pIter->pOrder);

  int eOp,
  const char *z3,
  const char *z4,
  const char *zDb,
  const char *zTrigger
){
  int rc = SQLITE_OK;
  (void)z4;
  (void)zTrigger;
  if( eOp==SQLITE_INSERT || eOp==SQLITE_UPDATE || eOp==SQLITE_DELETE ){
    if( sqlite3_stricmp(zDb, "main")==0 ){
      sqlite3expert *p = (sqlite3expert*)pCtx;
      IdxTable *pTab;
      for(pTab=p->pTable; pTab; pTab=pTab->pNext){
        if( 0==sqlite3_stricmp(z3, pTab->zName) ) break;
      }

  sqlite3_context *pCtx,
  int argc,
  sqlite3_value **argv
){
  struct IdxSampleCtx *p = (struct IdxSampleCtx*)sqlite3_user_data(pCtx);
  int bRet;

  (void)argv;
  assert( argc==0 );
  if( p->nRow==0.0 ){
    bRet = 1;
  }else{
    bRet = (p->nRet / p->nRow) <= p->target;
    if( bRet==0 ){
      unsigned short rnd;

  IdxHashEntry *pEntry;

  /* Do trigger processing to collect any extra IdxScan structures */
  rc = idxProcessTriggers(p, pzErr);

  /* Create candidate indexes within the in-memory database file */
  if( rc==SQLITE_OK ){
    rc = idxCreateCandidates(p);
  }

  /* Generate the stat1 data */
  if( rc==SQLITE_OK ){
    rc = idxPopulateStat1(p, pzErr);
  }

*/
static void shellPutsFunc(
  sqlite3_context *pCtx,
  int nVal,
  sqlite3_value **apVal
){
  ShellState *p = (ShellState*)sqlite3_user_data(pCtx);
  (void)nVal;
  utf8_printf(p->out, "%s\n", sqlite3_value_text(apVal[0]));
  sqlite3_result_value(pCtx, apVal[0]);
}

/*
** SQL function:   edit(VALUE)
**                 edit(VALUE,EDITOR)

    }
  }else
#endif /* SQLITE_USER_AUTHENTICATION */

  if( c=='v' && strncmp(azArg[0], "version", n)==0 ){
    utf8_printf(p->out, "SQLite %s %s\n" /*extra-version-info*/,
        sqlite3_libversion(), sqlite3_sourceid());
#if SQLITE_HAVE_ZLIB
    utf8_printf(p->out, "zlib version %s\n", zlibVersion());
#endif
#define CTIMEOPT_VAL_(opt) #opt
#define CTIMEOPT_VAL(opt) CTIMEOPT_VAL_(opt)
#if defined(__clang__) && defined(__clang_major__)
    utf8_printf(p->out, "clang-" CTIMEOPT_VAL(__clang_major__) "."
                    CTIMEOPT_VAL(__clang_minor__) "."
                    CTIMEOPT_VAL(__clang_patchlevel__) "\n");
#elif defined(_MSC_VER)
    utf8_printf(p->out, "msvc-" CTIMEOPT_VAL(_MSC_VER) "\n");
#elif defined(__GNUC__) && defined(__VERSION__)
    utf8_printf(p->out, "gcc-" __VERSION__ "\n");
#endif
  }else

  if( c=='v' && strncmp(azArg[0], "vfsinfo", n)==0 ){
    const char *zDbName = nArg==2 ? azArg[1] : "main";
    sqlite3_vfs *pVfs = 0;
    if( p->db ){
      sqlite3_file_control(p->db, zDbName, SQLITE_FCNTL_VFS_POINTER, &pVfs);

**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.22.0"
#define SQLITE_VERSION_NUMBER 3022000
#define SQLITE_SOURCE_ID      "2018-01-20 15:48:45 136bf323e42dc90e1780199a381bcbb084b069eca5c7343ee6fc6e2550831536"

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

#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))

#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
#define SQLITE_READONLY_DIRECTORY      (SQLITE_READONLY | (6<<8))

   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);

/*
** CAPI3REF: SQL Trace Event Codes
** KEYWORDS: SQLITE_TRACE
**
** These constants identify classes of events that can be monitored
** using the [sqlite3_trace_v2()] tracing logic.  The M argument
** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
** the following constants.  ^The first argument to the trace callback
** is one of the following constants.
**
** New tracing constants may be added in future releases.
**
** ^A trace callback has four arguments: xCallback(T,C,P,X).
** ^The T argument is one of the integer type codes above.

** no changes will be recorded in either of these scenarios.
**
** Changes are not recorded for individual rows that have NULL values stored
** in one or more of their PRIMARY KEY columns.
**
** SQLITE_OK is returned if the call completes without error. Or, if an error 
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
**
** <h3>Special sqlite_stat1 Handling</h3>
**
** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to 
** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
**  <pre>
**  &nbsp;     CREATE TABLE sqlite_stat1(tbl,idx,stat)  
**  </pre>
**
** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are 
** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes 
** are recorded for rows for which (idx IS NULL) is true. However, for such
** rows a zero-length blob (SQL value X'') is stored in the changeset or
** patchset instead of a NULL value. This allows such changesets to be
** manipulated by legacy implementations of sqlite3changeset_invert(),
** concat() and similar.
**
** The sqlite3changeset_apply() function automatically converts the 
** zero-length blob back to a NULL value when updating the sqlite_stat1
** table. However, if the application calls sqlite3changeset_new(),
** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset 
** iterator directly (including on a changeset iterator passed to a
** conflict-handler callback) then the X'' value is returned. The application
** must translate X'' to NULL itself if required.
**
** Legacy (older than 3.22.0) versions of the sessions module cannot capture
** changes made to the sqlite_stat1 table. Legacy versions of the
** sqlite3changeset_apply() function silently ignore any modifications to the
** sqlite_stat1 table that are part of a changeset or patchset.
*/
SQLITE_API int sqlite3session_attach(
  sqlite3_session *pSession,      /* Session object */
  const char *zTab                /* Table name */
);

/*

  FuncDef *pFunc;         /* Pointer to function information */
  Mem *pMem;              /* Memory cell used to store aggregate context */
  Vdbe *pVdbe;            /* The VM that owns this context */
  int iOp;                /* Instruction number of OP_Function */
  int isError;            /* Error code returned by the function. */
  u8 skipFlag;            /* Skip accumulator loading if true */
  u8 fErrorOrAux;         /* isError!=0 or pVdbe->pAuxData modified */

  u8 argc;                /* Number of arguments */
  sqlite3_value *argv[1]; /* Argument set */
};

/* A bitfield type for use inside of structures.  Always follow with :N where
** N is the number of bits.
*/

/*
** Compute 10 to the E-th power.  Examples:  E==1 results in 10.
** E==2 results in 100.  E==50 results in 1.0e50.
**
** This routine only works for values of E between 1 and 341.
*/
static LONGDOUBLE_TYPE sqlite3Pow10(int E){
#if defined(_MSC_VER)
  static const LONGDOUBLE_TYPE x[] = {
    1.0e+001,
    1.0e+002,
    1.0e+004,
    1.0e+008,
    1.0e+016,
    1.0e+032,
    1.0e+064,
    1.0e+128,
    1.0e+256
  };
  LONGDOUBLE_TYPE r = 1.0;
  int i;
  assert( E>=0 && E<=307 );
  for(i=0; E!=0; i++, E >>=1){
    if( E & 1 ) r *= x[i];
  }
  return r;
#else
  LONGDOUBLE_TYPE x = 10.0;
  LONGDOUBLE_TYPE r = 1.0;
  while(1){
    if( E & 1 ) r *= x;
    E >>= 1;
    if( E==0 ) break;
    x *= x;
  }
  return r; 
#endif
}

/*
** The string z[] is an text representation of a real number.
** Convert this string to a double and write it into *pResult.
**
** The string z[] is length bytes in length (bytes, not characters) and

** file are currently open, in this process or in other processes, then
** the file must be truncated to zero length or have its header cleared.
*/
static int winOpenSharedMemory(winFile *pDbFd){
  struct winShm *p;                  /* The connection to be opened */
  winShmNode *pShmNode = 0;          /* The underlying mmapped file */
  int rc = SQLITE_OK;                /* Result code */

  winShmNode *pNew;                  /* Newly allocated winShmNode */
  int nName;                         /* Size of zName in bytes */

  assert( pDbFd->pShm==0 );    /* Not previously opened */

  /* Allocate space for the new sqlite3_shm object.  Also speculatively
  ** allocate space for a new winShmNode and filename.

    ** use FILE_ID_BOTH_DIR_INFO Structure.
    */
    if( sqlite3StrICmp(pShmNode->zFilename, pNew->zFilename)==0 ) break;
  }
  if( pShmNode ){
    sqlite3_free(pNew);
  }else{
    int inFlags = SQLITE_OPEN_WAL;
    int outFlags = 0;

    pShmNode = pNew;
    pNew = 0;
    ((winFile*)(&pShmNode->hFile))->h = INVALID_HANDLE_VALUE;
    pShmNode->pNext = winShmNodeList;
    winShmNodeList = pShmNode;

    if( sqlite3GlobalConfig.bCoreMutex ){
      pShmNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
      if( pShmNode->mutex==0 ){
        rc = SQLITE_IOERR_NOMEM_BKPT;
        goto shm_open_err;
      }
    }

    if( 0==sqlite3_uri_boolean(pDbFd->zPath, "readonly_shm", 0) ){
      inFlags |= SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE;
    }else{

      inFlags |= SQLITE_OPEN_READONLY;

    }

    rc = winOpen(pDbFd->pVfs, pShmNode->zFilename,

                 (sqlite3_file*)&pShmNode->hFile,

                 inFlags, &outFlags);
    if( rc!=SQLITE_OK ){
      rc = winLogError(rc, osGetLastError(), "winOpenShm",
                       pShmNode->zFilename);
      goto shm_open_err;
    }
    if( outFlags==SQLITE_OPEN_READONLY ) pShmNode->isReadonly = 1;


    rc = winLockSharedMemory(pShmNode);
    if( rc!=SQLITE_OK && rc!=SQLITE_READONLY_CANTINIT ) goto shm_open_err;
  }

  /* Make the new connection a child of the winShmNode */
  p->pShmNode = pShmNode;

      h = osCreateFile2((LPCWSTR)zConverted,
                        dwDesiredAccess,
                        dwShareMode,
                        dwCreationDisposition,
                        &extendedParameters);
      if( h!=INVALID_HANDLE_VALUE ) break;
      if( isReadWrite ){
        int rc2, isRO = 0;
        sqlite3BeginBenignMalloc();
        rc2 = winAccess(pVfs, zName, SQLITE_ACCESS_READ, &isRO);
        sqlite3EndBenignMalloc();
        if( rc2==SQLITE_OK && isRO ) break;
      }
    }while( winRetryIoerr(&cnt, &lastErrno) );
#else
    do{
      h = osCreateFileW((LPCWSTR)zConverted,
                        dwDesiredAccess,
                        dwShareMode, NULL,
                        dwCreationDisposition,
                        dwFlagsAndAttributes,
                        NULL);
      if( h!=INVALID_HANDLE_VALUE ) break;
      if( isReadWrite ){
        int rc2, isRO = 0;
        sqlite3BeginBenignMalloc();
        rc2 = winAccess(pVfs, zName, SQLITE_ACCESS_READ, &isRO);
        sqlite3EndBenignMalloc();
        if( rc2==SQLITE_OK && isRO ) break;
      }
    }while( winRetryIoerr(&cnt, &lastErrno) );
#endif
  }
#ifdef SQLITE_WIN32_HAS_ANSI
  else{
    do{
      h = osCreateFileA((LPCSTR)zConverted,
                        dwDesiredAccess,
                        dwShareMode, NULL,
                        dwCreationDisposition,
                        dwFlagsAndAttributes,
                        NULL);
      if( h!=INVALID_HANDLE_VALUE ) break;
      if( isReadWrite ){
        int rc2, isRO = 0;
        sqlite3BeginBenignMalloc();
        rc2 = winAccess(pVfs, zName, SQLITE_ACCESS_READ, &isRO);
        sqlite3EndBenignMalloc();
        if( rc2==SQLITE_OK && isRO ) break;
      }
    }while( winRetryIoerr(&cnt, &lastErrno) );
  }
#endif
  winLogIoerr(cnt, __LINE__);

  if( p ){
    int i;
    for(i=0; i<p->nExpr; i++){
      heightOfExpr(p->a[i].pExpr, pnHeight);
    }
  }
}
static void heightOfSelect(Select *pSelect, int *pnHeight){
  Select *p;
  for(p=pSelect; p; p=p->pPrior){
    heightOfExpr(p->pWhere, pnHeight);
    heightOfExpr(p->pHaving, pnHeight);
    heightOfExpr(p->pLimit, pnHeight);
    heightOfExprList(p->pEList, pnHeight);
    heightOfExprList(p->pGroupBy, pnHeight);
    heightOfExprList(p->pOrderBy, pnHeight);

  }
}

/*
** Set the Expr.nHeight variable in the structure passed as an 
** argument. An expression with no children, Expr.pList or 
** Expr.pSelect member has a height of 1. Any other expression

    jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, regStat1); VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
    assert( "BBB"[0]==SQLITE_AFF_TEXT );
    sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regTemp, "BBB", 0);
    sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regNewRowid);
    sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regTemp, regNewRowid);
    sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
    sqlite3VdbeChangeP4(v, -1, (char*)pStat1, P4_TABLE);
#endif
    sqlite3VdbeJumpHere(v, jZeroRows);
  }
}


/*
** Generate code that will cause the most recent index analysis to

  int (*prepare16_v3)(sqlite3*,const void*,int,unsigned int,
                      sqlite3_stmt**,const void**);
  int (*bind_pointer)(sqlite3_stmt*,int,void*,const char*,void(*)(void*));
  void (*result_pointer)(sqlite3_context*,void*,const char*,void(*)(void*));
  void *(*value_pointer)(sqlite3_value*,const char*);
  int (*vtab_nochange)(sqlite3_context*);
  int (*value_nochange)(sqlite3_value*);
  const char *(*vtab_collation)(sqlite3_index_info*,int);
};

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

#define sqlite3_prepare16_v3           sqlite3_api->prepare16_v3
#define sqlite3_bind_pointer           sqlite3_api->bind_pointer
#define sqlite3_result_pointer         sqlite3_api->result_pointer
#define sqlite3_value_pointer          sqlite3_api->value_pointer
/* Version 3.22.0 and later */
#define sqlite3_vtab_nochange          sqlite3_api->vtab_nochange
#define sqlite3_value_nochange         sqltie3_api->value_nochange
#define sqlite3_vtab_collation         sqltie3_api->vtab_collation
#endif /* !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION) */

#if !defined(SQLITE_CORE) && !defined(SQLITE_OMIT_LOAD_EXTENSION)
  /* This case when the file really is being compiled as a loadable 
  ** extension */
# define SQLITE_EXTENSION_INIT1     const sqlite3_api_routines *sqlite3_api=0;
# define SQLITE_EXTENSION_INIT2(v)  sqlite3_api=v;

  sqlite3_prepare_v3,
  sqlite3_prepare16_v3,
  sqlite3_bind_pointer,
  sqlite3_result_pointer,
  sqlite3_value_pointer,
  /* Version 3.22.0 and later */
  sqlite3_vtab_nochange,
  sqlite3_value_nochange,
  sqlite3_vtab_collation
};

/*
** Attempt to load an SQLite extension library contained in the file
** zFile.  The entry point is zProc.  zProc may be 0 in which case a
** default entry point name (sqlite3_extension_init) is used.  Use
** of the default name is recommended.

  sqlite3ParserTOKENTYPE yyLookaheadToken  /* Value of the lookahead token */
){
  int yygoto;                     /* The next state */
  int yyact;                      /* The next action */
  yyStackEntry *yymsp;            /* The top of the parser's stack */
  int yysize;                     /* Amount to pop the stack */
  sqlite3ParserARG_FETCH;
  (void)yyLookahead;
  (void)yyLookaheadToken;
  yymsp = yypParser->yytos;
#ifndef NDEBUG
  if( yyTraceFILE && yyruleno<(int)(sizeof(yyRuleName)/sizeof(yyRuleName[0])) ){
    yysize = yyRuleInfo[yyruleno].nrhs;
    if( yysize ){
      fprintf(yyTraceFILE, "%sReduce %d [%s], go to state %d.\n",
        yyTracePrompt,

**
******************************************************************************
**
** This header file is used by programs that want to link against the
** RTREE library.  All it does is declare the sqlite3RtreeInit() interface.
*/
/* #include "sqlite3.h" */

#ifdef SQLITE_OMIT_VIRTUALTABLE
# undef SQLITE_ENABLE_RTREE
#endif

#if 0
extern "C" {
#endif  /* __cplusplus */

SQLITE_PRIVATE int sqlite3RtreeInit(sqlite3 *db);

**   3. The remainder of the node contains the node entries. Each entry
**      consists of a single 8-byte integer followed by an even number
**      of 4-byte coordinates. For leaf nodes the integer is the rowid
**      of a record. For internal nodes it is the node number of a
**      child page.
*/

#if !defined(SQLITE_CORE) \
  || (defined(SQLITE_ENABLE_RTREE) && !defined(SQLITE_OMIT_VIRTUALTABLE))

#ifndef SQLITE_CORE
/*   #include "sqlite3ext.h" */
  SQLITE_EXTENSION_INIT1
#else
/*   #include "sqlite3.h" */
#endif

  char *zDb;                      /* Name of database session is attached to */
  int bEnable;                    /* True if currently recording */
  int bIndirect;                  /* True if all changes are indirect */
  int bAutoAttach;                /* True to auto-attach tables */
  int rc;                         /* Non-zero if an error has occurred */
  void *pFilterCtx;               /* First argument to pass to xTableFilter */
  int (*xTableFilter)(void *pCtx, const char *zTab);
  sqlite3_value *pZeroBlob;       /* Value containing X'' */
  sqlite3_session *pNext;         /* Next session object on same db. */
  SessionTable *pTable;           /* List of attached tables */
  SessionHook hook;               /* APIs to grab new and old data with */
};

/*
** Instances of this structure are used to build strings or binary records.

** a subset of the initial values that the modified row contained at the
** start of the session. Or no initial values if the row was inserted.
*/
struct SessionTable {
  SessionTable *pNext;
  char *zName;                    /* Local name of table */
  int nCol;                       /* Number of columns in table zName */
  int bStat1;                     /* True if this is sqlite_stat1 */
  const char **azCol;             /* Column names */
  u8 *abPK;                       /* Array of primary key flags */
  int nEntry;                     /* Total number of entries in hash table */
  int nChange;                    /* Size of apChange[] array */
  SessionChange **apChange;       /* Hash table buckets */
};

          z = (const u8 *)sqlite3_value_blob(pVal);
        }
        n = sqlite3_value_bytes(pVal);
        if( !z && (eType!=SQLITE_BLOB || n>0) ) return SQLITE_NOMEM;
        h = sessionHashAppendBlob(h, n, z);
      }else{
        assert( eType==SQLITE_NULL );
        assert( pTab->bStat1==0 || i!=1 );
        *pbNullPK = 1;
      }
    }
  }

  *piHash = (h % pTab->nChange);
  return SQLITE_OK;

        if( eType==SQLITE_TEXT ){
          z = sqlite3_value_text(pVal);
        }else{
          z = sqlite3_value_blob(pVal);
        }
        if( memcmp(a, z, n) ) return 0;
        a += n;

      }
    }
  }

  return 1;
}

      int i;
      for(i=0; i<pTab->nCol; i++){
        if( abPK[i] ){
          pTab->abPK = abPK;
          break;
        }
      }
      if( 0==sqlite3_stricmp("sqlite_stat1", pTab->zName) ){
        pTab->bStat1 = 1;
      }
    }
  }
  return (pSession->rc || pTab->abPK==0);
}

/*
** Versions of the four methods in object SessionHook for use with the
** sqlite_stat1 table. The purpose of this is to substitute a zero-length
** blob each time a NULL value is read from the "idx" column of the
** sqlite_stat1 table.
*/
typedef struct SessionStat1Ctx SessionStat1Ctx;
struct SessionStat1Ctx {
  SessionHook hook;
  sqlite3_session *pSession;
};
static int sessionStat1Old(void *pCtx, int iCol, sqlite3_value **ppVal){
  SessionStat1Ctx *p = (SessionStat1Ctx*)pCtx;
  sqlite3_value *pVal = 0;
  int rc = p->hook.xOld(p->hook.pCtx, iCol, &pVal);
  if( rc==SQLITE_OK && iCol==1 && sqlite3_value_type(pVal)==SQLITE_NULL ){
    pVal = p->pSession->pZeroBlob;
  }
  *ppVal = pVal;
  return rc;
}
static int sessionStat1New(void *pCtx, int iCol, sqlite3_value **ppVal){
  SessionStat1Ctx *p = (SessionStat1Ctx*)pCtx;
  sqlite3_value *pVal = 0;
  int rc = p->hook.xNew(p->hook.pCtx, iCol, &pVal);
  if( rc==SQLITE_OK && iCol==1 && sqlite3_value_type(pVal)==SQLITE_NULL ){
    pVal = p->pSession->pZeroBlob;
  }
  *ppVal = pVal;
  return rc;
}
static int sessionStat1Count(void *pCtx){
  SessionStat1Ctx *p = (SessionStat1Ctx*)pCtx;
  return p->hook.xCount(p->hook.pCtx);
}
static int sessionStat1Depth(void *pCtx){
  SessionStat1Ctx *p = (SessionStat1Ctx*)pCtx;
  return p->hook.xDepth(p->hook.pCtx);
}


/*
** This function is only called from with a pre-update-hook reporting a 
** change on table pTab (attached to session pSession). The type of change
** (UPDATE, INSERT, DELETE) is specified by the first argument.
**
** Unless one is already present or an error occurs, an entry is added
** to the changed-rows hash table associated with table pTab.
*/
static void sessionPreupdateOneChange(
  int op,                         /* One of SQLITE_UPDATE, INSERT, DELETE */
  sqlite3_session *pSession,      /* Session object pTab is attached to */
  SessionTable *pTab              /* Table that change applies to */
){
  int iHash; 
  int bNull = 0; 
  int rc = SQLITE_OK;
  SessionStat1Ctx stat1;

  if( pSession->rc ) return;

  /* Load table details if required */
  if( sessionInitTable(pSession, pTab) ) return;

  /* Check the number of columns in this xPreUpdate call matches the 
  ** number of columns in the table.  */
  if( pTab->nCol!=pSession->hook.xCount(pSession->hook.pCtx) ){
    pSession->rc = SQLITE_SCHEMA;
    return;
  }

  /* Grow the hash table if required */
  if( sessionGrowHash(0, pTab) ){
    pSession->rc = SQLITE_NOMEM;
    return;
  }

  if( pTab->bStat1 ){
    stat1.hook = pSession->hook;
    stat1.pSession = pSession;
    pSession->hook.pCtx = (void*)&stat1;
    pSession->hook.xNew = sessionStat1New;
    pSession->hook.xOld = sessionStat1Old;
    pSession->hook.xCount = sessionStat1Count;
    pSession->hook.xDepth = sessionStat1Depth;
    if( pSession->pZeroBlob==0 ){
      sqlite3_value *p = sqlite3ValueNew(0);
      if( p==0 ){
        rc = SQLITE_NOMEM;
        goto error_out;
      }
      sqlite3ValueSetStr(p, 0, "", 0, SQLITE_STATIC);
      pSession->pZeroBlob = p;
    }
  }

  /* Calculate the hash-key for this change. If the primary key of the row
  ** includes a NULL value, exit early. Such changes are ignored by the
  ** session module. */
  rc = sessionPreupdateHash(pSession, pTab, op==SQLITE_INSERT, &iHash, &bNull);
  if( rc!=SQLITE_OK ) goto error_out;

        pC->bIndirect = 0;
      }
    }
  }

  /* If an error has occurred, mark the session object as failed. */
 error_out:
  if( pTab->bStat1 ){
    pSession->hook = stat1.hook;
  }
  if( rc!=SQLITE_OK ){
    pSession->rc = rc;
  }
}

static int sessionFindTable(
  sqlite3_session *pSession, 

    if( (*pp)==pSession ){
      *pp = (*pp)->pNext;
      if( pHead ) sqlite3_preupdate_hook(db, xPreUpdate, (void*)pHead);
      break;
    }
  }
  sqlite3_mutex_leave(sqlite3_db_mutex(db));
  sqlite3ValueFree(pSession->pZeroBlob);

  /* Delete all attached table objects. And the contents of their 
  ** associated hash-tables. */
  sessionDeleteTable(pSession->pTable);

  /* Free the session object itself. */
  sqlite3_free(pSession);

  const char *zTab,               /* Table name */
  int nCol,                       /* Number of columns in table */
  const char **azCol,             /* Names of table columns */
  u8 *abPK,                       /* PRIMARY KEY  array */
  sqlite3_stmt **ppStmt           /* OUT: Prepared SELECT statement */
){
  int rc = SQLITE_OK;
  char *zSql = 0;
  int nSql = -1;

  if( 0==sqlite3_stricmp("sqlite_stat1", zTab) ){
    zSql = sqlite3_mprintf(
        "SELECT tbl, ?2, stat FROM %Q.sqlite_stat1 WHERE tbl IS ?1 AND "
        "idx IS (CASE WHEN ?2=X'' THEN NULL ELSE ?2 END)", zDb
    );
  }else{
    int i;
    const char *zSep = "";
    SessionBuffer buf = {0, 0, 0};

    sessionAppendStr(&buf, "SELECT * FROM ", &rc);
    sessionAppendIdent(&buf, zDb, &rc);
    sessionAppendStr(&buf, ".", &rc);
    sessionAppendIdent(&buf, zTab, &rc);
    sessionAppendStr(&buf, " WHERE ", &rc);
    for(i=0; i<nCol; i++){
      if( abPK[i] ){
        sessionAppendStr(&buf, zSep, &rc);
        sessionAppendIdent(&buf, azCol[i], &rc);
        sessionAppendStr(&buf, " IS ?", &rc);
        sessionAppendInteger(&buf, i+1, &rc);
        zSep = " AND ";
      }
    }
    zSql = (char*)buf.aBuf;
    nSql = buf.nBuf;
  }

  if( rc==SQLITE_OK ){
    rc = sqlite3_prepare_v2(db, zSql, nSql, ppStmt, 0);
  }
  sqlite3_free(zSql);
  return rc;
}

/*
** Bind the PRIMARY KEY values from the change passed in argument pChange
** to the SELECT statement passed as the first argument. The SELECT statement
** is as prepared by function sessionSelectStmt().

  sqlite3_stmt *pDelete;          /* DELETE statement */
  sqlite3_stmt *pUpdate;          /* UPDATE statement */
  sqlite3_stmt *pInsert;          /* INSERT statement */
  sqlite3_stmt *pSelect;          /* SELECT statement */
  int nCol;                       /* Size of azCol[] and abPK[] arrays */
  const char **azCol;             /* Array of column names */
  u8 *abPK;                       /* Boolean array - true if column is in PK */
  int bStat1;                     /* True if table is sqlite_stat1 */
  int bDeferConstraints;          /* True to defer constraints */
  SessionBuffer constraints;      /* Deferred constraints are stored here */
};

/*
** Formulate a statement to DELETE a row from database db. Assuming a table
** structure like this:

  if( rc==SQLITE_OK ){
    rc = sqlite3_prepare_v2(db, (char *)buf.aBuf, buf.nBuf, &p->pUpdate, 0);
  }
  sqlite3_free(buf.aBuf);

  return rc;
}


/*
** Formulate and prepare an SQL statement to query table zTab by primary
** key. Assuming the following table structure:
**
**     CREATE TABLE x(a, b, c, d, PRIMARY KEY(a, c));
**

  if( rc==SQLITE_OK ){
    rc = sqlite3_prepare_v2(db, (char *)buf.aBuf, buf.nBuf, &p->pInsert, 0);
  }
  sqlite3_free(buf.aBuf);
  return rc;
}

static int sessionPrepare(sqlite3 *db, sqlite3_stmt **pp, const char *zSql){
  return sqlite3_prepare_v2(db, zSql, -1, pp, 0);
}

/*
** Prepare statements for applying changes to the sqlite_stat1 table.
** These are similar to those created by sessionSelectRow(),
** sessionInsertRow(), sessionUpdateRow() and sessionDeleteRow() for 
** other tables.
*/
static int sessionStat1Sql(sqlite3 *db, SessionApplyCtx *p){
  int rc = sessionSelectRow(db, "sqlite_stat1", p);
  if( rc==SQLITE_OK ){
    rc = sessionPrepare(db, &p->pInsert,
        "INSERT INTO main.sqlite_stat1 VALUES(?1, "
        "CASE WHEN length(?2)=0 AND typeof(?2)='blob' THEN NULL ELSE ?2 END, "
        "?3)"
    );
  }
  if( rc==SQLITE_OK ){
    rc = sessionPrepare(db, &p->pUpdate,
        "UPDATE main.sqlite_stat1 SET "
        "tbl = CASE WHEN ?2 THEN ?3 ELSE tbl END, "
        "idx = CASE WHEN ?5 THEN ?6 ELSE idx END, "
        "stat = CASE WHEN ?8 THEN ?9 ELSE stat END  "
        "WHERE tbl=?1 AND idx IS "
        "CASE WHEN length(?4)=0 AND typeof(?4)='blob' THEN NULL ELSE ?4 END "
        "AND (?10 OR ?8=0 OR stat IS ?7)"
    );
  }
  if( rc==SQLITE_OK ){
    rc = sessionPrepare(db, &p->pDelete,
        "DELETE FROM main.sqlite_stat1 WHERE tbl=?1 AND idx IS "
        "CASE WHEN length(?2)=0 AND typeof(?2)='blob' THEN NULL ELSE ?2 END "
        "AND (?4 OR stat IS ?3)"
    );
  }
  assert( rc==SQLITE_OK );
  return rc;
}

/*
** A wrapper around sqlite3_bind_value() that detects an extra problem. 
** See comments in the body of this function for details.
*/
static int sessionBindValue(
  sqlite3_stmt *pStmt,            /* Statement to bind value to */

      rc = sessionConflictHandler(
          SQLITE_CHANGESET_CONFLICT, p, pIter, xConflict, pCtx, 0
      );
    }

  }else{
    assert( op==SQLITE_INSERT );
    if( p->bStat1 ){
      /* Check if there is a conflicting row. For sqlite_stat1, this needs
      ** to be done using a SELECT, as there is no PRIMARY KEY in the 
      ** database schema to throw an exception if a duplicate is inserted.  */
      rc = sessionSeekToRow(p->db, pIter, p->abPK, p->pSelect);
      if( rc==SQLITE_ROW ){
        rc = SQLITE_CONSTRAINT;
        sqlite3_reset(p->pSelect);
      }
    }

    if( rc==SQLITE_OK ){
      rc = sessionBindRow(pIter, sqlite3changeset_new, nCol, 0, p->pInsert);
      if( rc!=SQLITE_OK ) return rc;

      sqlite3_step(p->pInsert);
      rc = sqlite3_reset(p->pInsert);
    }

    if( (rc&0xff)==SQLITE_CONSTRAINT ){
      rc = sessionConflictHandler(
          SQLITE_CHANGESET_CONFLICT, p, pIter, xConflict, pCtx, pbReplace
      );
    }
  }

          schemaMismatch = 1;
          sqlite3_log(SQLITE_SCHEMA, "sqlite3changeset_apply(): "
              "primary key mismatch for table %s", zTab
          );
        }
        else{
          sApply.nCol = nCol;
          if( 0==sqlite3_stricmp(zTab, "sqlite_stat1") ){
            if( (rc = sessionStat1Sql(db, &sApply) ) ){
              break;
            }
            sApply.bStat1 = 1;
          }else{
            if((rc = sessionSelectRow(db, zTab, &sApply))
                || (rc = sessionUpdateRow(db, zTab, &sApply))
                || (rc = sessionDeleteRow(db, zTab, &sApply))
                || (rc = sessionInsertRow(db, zTab, &sApply))
              ){
              break;
            }
            sApply.bStat1 = 0;
          }
        }
        nTab = sqlite3Strlen30(zTab);
      }
    }

    /* If there is a schema mismatch on the current table, proceed to the

  sqlite3Fts5ParserFTS5TOKENTYPE fts5yyLookaheadToken  /* Value of the lookahead token */
){
  int fts5yygoto;                     /* The next state */
  int fts5yyact;                      /* The next action */
  fts5yyStackEntry *fts5yymsp;            /* The top of the parser's stack */
  int fts5yysize;                     /* Amount to pop the stack */
  sqlite3Fts5ParserARG_FETCH;
  (void)fts5yyLookahead;
  (void)fts5yyLookaheadToken;
  fts5yymsp = fts5yypParser->fts5yytos;
#ifndef NDEBUG
  if( fts5yyTraceFILE && fts5yyruleno<(int)(sizeof(fts5yyRuleName)/sizeof(fts5yyRuleName[0])) ){
    fts5yysize = fts5yyRuleInfo[fts5yyruleno].nrhs;
    if( fts5yysize ){
      fprintf(fts5yyTraceFILE, "%sReduce %d [%s], go to state %d.\n",
        fts5yyTracePrompt,

static void fts5SourceIdFunc(
  sqlite3_context *pCtx,          /* Function call context */
  int nArg,                       /* Number of args */
  sqlite3_value **apUnused        /* Function arguments */
){
  assert( nArg==0 );
  UNUSED_PARAM2(nArg, apUnused);
  sqlite3_result_text(pCtx, "fts5: 2018-01-20 15:48:45 136bf323e42dc90e1780199a381bcbb084b069eca5c7343ee6fc6e2550831536", -1, SQLITE_TRANSIENT);
}

static int fts5Init(sqlite3 *db){
  static const sqlite3_module fts5Mod = {
    /* iVersion      */ 2,
    /* xCreate       */ fts5CreateMethod,
    /* xConnect      */ fts5ConnectMethod,

#endif
  return rc;
}
#endif /* SQLITE_CORE */
#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_STMTVTAB) */

/************** End of stmt.c ************************************************/
#if __LINE__!=207601
#undef SQLITE_SOURCE_ID
#define SQLITE_SOURCE_ID      "2018-01-20 15:48:45 136bf323e42dc90e1780199a381bcbb084b069eca5c7343ee6fc6e255083alt2"
#endif
/* Return the source-id for this library */
SQLITE_API const char *sqlite3_sourceid(void){ return SQLITE_SOURCE_ID; }
/************************** End of sqlite3.c ******************************/

**
** See also: [sqlite3_libversion()],
** [sqlite3_libversion_number()], [sqlite3_sourceid()],
** [sqlite_version()] and [sqlite_source_id()].
*/
#define SQLITE_VERSION        "3.22.0"
#define SQLITE_VERSION_NUMBER 3022000
#define SQLITE_SOURCE_ID      "2018-01-20 15:48:45 136bf323e42dc90e1780199a381bcbb084b069eca5c7343ee6fc6e2550831536"

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

#define SQLITE_LOCKED_SHAREDCACHE      (SQLITE_LOCKED |  (1<<8))
#define SQLITE_BUSY_RECOVERY           (SQLITE_BUSY   |  (1<<8))
#define SQLITE_BUSY_SNAPSHOT           (SQLITE_BUSY   |  (2<<8))
#define SQLITE_CANTOPEN_NOTEMPDIR      (SQLITE_CANTOPEN | (1<<8))
#define SQLITE_CANTOPEN_ISDIR          (SQLITE_CANTOPEN | (2<<8))
#define SQLITE_CANTOPEN_FULLPATH       (SQLITE_CANTOPEN | (3<<8))
#define SQLITE_CANTOPEN_CONVPATH       (SQLITE_CANTOPEN | (4<<8))

#define SQLITE_CORRUPT_VTAB            (SQLITE_CORRUPT | (1<<8))
#define SQLITE_READONLY_RECOVERY       (SQLITE_READONLY | (1<<8))
#define SQLITE_READONLY_CANTLOCK       (SQLITE_READONLY | (2<<8))
#define SQLITE_READONLY_ROLLBACK       (SQLITE_READONLY | (3<<8))
#define SQLITE_READONLY_DBMOVED        (SQLITE_READONLY | (4<<8))
#define SQLITE_READONLY_CANTINIT       (SQLITE_READONLY | (5<<8))
#define SQLITE_READONLY_DIRECTORY      (SQLITE_READONLY | (6<<8))

   void(*xProfile)(void*,const char*,sqlite3_uint64), void*);

/*
** CAPI3REF: SQL Trace Event Codes
** KEYWORDS: SQLITE_TRACE
**
** These constants identify classes of events that can be monitored
** using the [sqlite3_trace_v2()] tracing logic.  The M argument
** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of
** the following constants.  ^The first argument to the trace callback
** is one of the following constants.
**
** New tracing constants may be added in future releases.
**
** ^A trace callback has four arguments: xCallback(T,C,P,X).
** ^The T argument is one of the integer type codes above.

** no changes will be recorded in either of these scenarios.
**
** Changes are not recorded for individual rows that have NULL values stored
** in one or more of their PRIMARY KEY columns.
**
** SQLITE_OK is returned if the call completes without error. Or, if an error 
** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.
**
** <h3>Special sqlite_stat1 Handling</h3>
**
** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to 
** some of the rules above. In SQLite, the schema of sqlite_stat1 is:
**  <pre>
**  &nbsp;     CREATE TABLE sqlite_stat1(tbl,idx,stat)  
**  </pre>
**
** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are 
** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes 
** are recorded for rows for which (idx IS NULL) is true. However, for such
** rows a zero-length blob (SQL value X'') is stored in the changeset or
** patchset instead of a NULL value. This allows such changesets to be
** manipulated by legacy implementations of sqlite3changeset_invert(),
** concat() and similar.
**
** The sqlite3changeset_apply() function automatically converts the 
** zero-length blob back to a NULL value when updating the sqlite_stat1
** table. However, if the application calls sqlite3changeset_new(),
** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset 
** iterator directly (including on a changeset iterator passed to a
** conflict-handler callback) then the X'' value is returned. The application
** must translate X'' to NULL itself if required.
**
** Legacy (older than 3.22.0) versions of the sessions module cannot capture
** changes made to the sqlite_stat1 table. Legacy versions of the
** sqlite3changeset_apply() function silently ignore any modifications to the
** sqlite_stat1 table that are part of a changeset or patchset.
*/
SQLITE_API int sqlite3session_attach(
  sqlite3_session *pSession,      /* Session object */
  const char *zTab                /* Table name */
);

/*