}
#endif   /* !SQLITE_OMIT_TRIGGER */

/*
** Register built-in functions used to help implement ALTER TABLE
*/
void sqlite3AlterFunctions(void){
  static SQLITE_WSD FuncDef aAlterTableFuncs[] = {
    FUNCTION(sqlite_rename_table,   2, 0, 0, renameTableFunc),
#ifndef SQLITE_OMIT_TRIGGER
    FUNCTION(sqlite_rename_trigger, 2, 0, 0, renameTriggerFunc),
#endif
#ifndef SQLITE_OMIT_FOREIGN_KEY
    FUNCTION(sqlite_rename_parent,  3, 0, 0, renameParentFunc),
#endif
  };
  int i;
  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aAlterTableFuncs);

  for(i=0; i<ArraySize(aAlterTableFuncs); i++){
    sqlite3FuncDefInsert(pHash, &aFunc[i]);
  }
}

/*
** This function is used to create the text of expressions of the form:
**
**   name=<constant1> OR name=<constant2> OR ...
**

  2+IsStat34,      /* nArg */
  SQLITE_UTF8,     /* funcFlags */
  0,               /* pUserData */
  0,               /* pNext */
  statInit,        /* xSFunc */
  0,               /* xFinalize */
  "stat_init",     /* zName */
  0,               /* pHash */
  0                /* pDestructor */
};

#ifdef SQLITE_ENABLE_STAT4
/*
** pNew and pOld are both candidate non-periodic samples selected for 
** the same column (pNew->iCol==pOld->iCol). Ignoring this column and 
** considering only any trailing columns and the sample hash value, this

  2+IsStat34,      /* nArg */
  SQLITE_UTF8,     /* funcFlags */
  0,               /* pUserData */
  0,               /* pNext */
  statPush,        /* xSFunc */
  0,               /* xFinalize */
  "stat_push",     /* zName */
  0,               /* pHash */
  0                /* pDestructor */
};

#define STAT_GET_STAT1 0          /* "stat" column of stat1 table */
#define STAT_GET_ROWID 1          /* "rowid" column of stat[34] entry */
#define STAT_GET_NEQ   2          /* "neq" column of stat[34] entry */
#define STAT_GET_NLT   3          /* "nlt" column of stat[34] entry */
#define STAT_GET_NDLT  4          /* "ndlt" column of stat[34] entry */

  1+IsStat34,      /* nArg */
  SQLITE_UTF8,     /* funcFlags */
  0,               /* pUserData */
  0,               /* pNext */
  statGet,         /* xSFunc */
  0,               /* xFinalize */
  "stat_get",      /* zName */
  0,               /* pHash */
  0                /* pDestructor */
};

static void callStatGet(Vdbe *v, int regStat4, int iParam, int regOut){
  assert( regOut!=regStat4 && regOut!=regStat4+1 );
#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
  sqlite3VdbeAddOp2(v, OP_Integer, iParam, regStat4+1);
#elif SQLITE_DEBUG

    1,                /* nArg */
    SQLITE_UTF8,      /* funcFlags */
    0,                /* pUserData */
    0,                /* pNext */
    detachFunc,       /* xSFunc */
    0,                /* xFinalize */
    "sqlite_detach",  /* zName */
    0,                /* pHash */
    0                 /* pDestructor */
  };
  codeAttach(pParse, SQLITE_DETACH, &detach_func, pDbname, 0, 0, pDbname);
}

/*
** Called by the parser to compile an ATTACH statement.
**
**     ATTACH p AS pDbname KEY pKey
*/
void sqlite3Attach(Parse *pParse, Expr *p, Expr *pDbname, Expr *pKey){
  static const FuncDef attach_func = {
    3,                /* nArg */
    SQLITE_UTF8,      /* funcFlags */
    0,                /* pUserData */
    0,                /* pNext */
    attachFunc,       /* xSFunc */
    0,                /* xFinalize */
    "sqlite_attach",  /* zName */
    0,                /* pHash */
    0                 /* pDestructor */
  };
  codeAttach(pParse, SQLITE_ATTACH, &attach_func, p, p, pDbname, pKey);
}
#endif /* SQLITE_OMIT_ATTACH */

/*
** Initialize a DbFixer structure.  This routine must be called prior

}

/*
** Search a FuncDefHash for a function with the given name.  Return
** a pointer to the matching FuncDef if found, or 0 if there is no match.
*/
static FuncDef *functionSearch(
  FuncDefHash *pHash,  /* Hash table to search */
  int h,               /* Hash of the name */
  const char *zFunc,   /* Name of function */
  int nFunc            /* Number of bytes in zFunc */
){
  FuncDef *p;
  for(p=pHash->a[h]; p; p=p->pHash){
    if( sqlite3StrNICmp(p->zName, zFunc, nFunc)==0 && p->zName[nFunc]==0 ){
      return p;
    }
  }
  return 0;
}

/*
** Insert a new FuncDef into a FuncDefHash hash table.
*/
void sqlite3FuncDefInsert(
  FuncDefHash *pHash,  /* The hash table into which to insert */
  FuncDef *pDef        /* The function definition to insert */
){


  FuncDef *pOther;

  int nName = sqlite3Strlen30(pDef->zName);
  u8 c1 = (u8)pDef->zName[0];
  int h = (sqlite3UpperToLower[c1] + nName) % ArraySize(pHash->a);
  pOther = functionSearch(pHash, h, pDef->zName, nName);
  if( pOther ){
    assert( pOther!=pDef && pOther->pNext!=pDef );
    pDef->pNext = pOther->pNext;
    pOther->pNext = pDef;
  }else{
    pDef->pNext = 0;
    pDef->pHash = pHash->a[h];
    pHash->a[h] = pDef;

  }
}
  
  

/*
** Locate a user function given a name, a number of arguments and a flag

**
** If createFlag is false, then a function with the required name and
** number of arguments may be returned even if the eTextRep flag does not
** match that requested.
*/
FuncDef *sqlite3FindFunction(
  sqlite3 *db,       /* An open database */
  const char *zName, /* Name of the function.  Not null-terminated */
  int nName,         /* Number of characters in the name */
  int nArg,          /* Number of arguments.  -1 means any number */
  u8 enc,            /* Preferred text encoding */
  u8 createFlag      /* Create new entry if true and does not otherwise exist */
){
  FuncDef *p;         /* Iterator variable */
  FuncDef *pBest = 0; /* Best match found so far */
  int bestScore = 0;  /* Score of best match */
  int h;              /* Hash value */


  assert( nArg>=(-2) );
  assert( nArg>=(-1) || createFlag==0 );
  h = (sqlite3UpperToLower[(u8)zName[0]] + nName) % ArraySize(db->aFunc.a);

  /* First search for a match amongst the application-defined functions.
  */
  p = functionSearch(&db->aFunc, h, zName, nName);
  while( p ){
    int score = matchQuality(p, nArg, enc);
    if( score>bestScore ){
      pBest = p;
      bestScore = score;
    }
    p = p->pNext;

  ** Except, if createFlag is true, that means that we are trying to
  ** install a new function.  Whatever FuncDef structure is returned it will
  ** have fields overwritten with new information appropriate for the
  ** new function.  But the FuncDefs for built-in functions are read-only.
  ** So we must not search for built-ins when creating a new function.
  */ 
  if( !createFlag && (pBest==0 || (db->flags & SQLITE_PreferBuiltin)!=0) ){
    FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
    bestScore = 0;

    p = functionSearch(pHash, h, zName, nName);
    while( p ){
      int score = matchQuality(p, nArg, enc);
      if( score>bestScore ){
        pBest = p;
        bestScore = score;
      }
      p = p->pNext;
    }
  }

  /* If the createFlag parameter is true and the search did not reveal an
  ** exact match for the name, number of arguments and encoding, then add a
  ** new entry to the hash table and return it.
  */
  if( createFlag && bestScore<FUNC_PERFECT_MATCH && 
      (pBest = sqlite3DbMallocZero(db, sizeof(*pBest)+nName+1))!=0 ){

    pBest->zName = (char *)&pBest[1];
    pBest->nArg = (u16)nArg;
    pBest->funcFlags = enc;
    memcpy(pBest->zName, zName, nName);
    pBest->zName[nName] = 0;

    sqlite3FuncDefInsert(&db->aFunc, pBest);





  }

  if( pBest && (pBest->xSFunc || createFlag) ){
    return pBest;
  }
  return 0;
}

/*
** This function registered all of the above C functions as SQL
** functions.  This should be the only routine in this file with
** external linkage.
*/
void sqlite3RegisterDateTimeFunctions(void){
  static SQLITE_WSD FuncDef aDateTimeFuncs[] = {
#ifndef SQLITE_OMIT_DATETIME_FUNCS
    DFUNCTION(julianday,        -1, 0, 0, juliandayFunc ),
    DFUNCTION(date,             -1, 0, 0, dateFunc      ),
    DFUNCTION(time,             -1, 0, 0, timeFunc      ),
    DFUNCTION(datetime,         -1, 0, 0, datetimeFunc  ),
    DFUNCTION(strftime,         -1, 0, 0, strftimeFunc  ),
    DFUNCTION(current_time,      0, 0, 0, ctimeFunc     ),
    DFUNCTION(current_timestamp, 0, 0, 0, ctimestampFunc),
    DFUNCTION(current_date,      0, 0, 0, cdateFunc     ),
#else
    STR_FUNCTION(current_time,      0, "%H:%M:%S",          0, currentTimeFunc),
    STR_FUNCTION(current_date,      0, "%Y-%m-%d",          0, currentTimeFunc),
    STR_FUNCTION(current_timestamp, 0, "%Y-%m-%d %H:%M:%S", 0, currentTimeFunc),
#endif
  };
  int i;
  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aDateTimeFuncs);

  for(i=0; i<ArraySize(aDateTimeFuncs); i++){
    sqlite3FuncDefInsert(pHash, &aFunc[i]);
  }
}

      }
      break;
    }
    case TK_FUNCTION: {
      ExprList *pFarg;       /* List of function arguments */
      int nFarg;             /* Number of function arguments */
      FuncDef *pDef;         /* The function definition object */
      int nId;               /* Length of the function name in bytes */
      const char *zId;       /* The function name */
      u32 constMask = 0;     /* Mask of function arguments that are constant */
      int i;                 /* Loop counter */
      u8 enc = ENC(db);      /* The text encoding used by this database */
      CollSeq *pColl = 0;    /* A collating sequence */

      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
      if( ExprHasProperty(pExpr, EP_TokenOnly) ){
        pFarg = 0;
      }else{
        pFarg = pExpr->x.pList;
      }
      nFarg = pFarg ? pFarg->nExpr : 0;
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      zId = pExpr->u.zToken;
      nId = sqlite3Strlen30(zId);
      pDef = sqlite3FindFunction(db, zId, nId, nFarg, enc, 0);
      if( pDef==0 || pDef->xFinalize!=0 ){
        sqlite3ErrorMsg(pParse, "unknown function: %.*s()", nId, zId);
        break;
      }

      /* Attempt a direct implementation of the built-in COALESCE() and
      ** IFNULL() functions.  This avoids unnecessary evaluation of
      ** arguments past the first non-NULL argument.
      */

          if( i>=0 ){
            assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
            pItem = &pAggInfo->aFunc[i];
            pItem->pExpr = pExpr;
            pItem->iMem = ++pParse->nMem;
            assert( !ExprHasProperty(pExpr, EP_IntValue) );
            pItem->pFunc = sqlite3FindFunction(pParse->db,
                   pExpr->u.zToken, sqlite3Strlen30(pExpr->u.zToken),
                   pExpr->x.pList ? pExpr->x.pList->nExpr : 0, enc, 0);
            if( pExpr->flags & EP_Distinct ){
              pItem->iDistinct = pParse->nTab++;
            }else{
              pItem->iDistinct = -1;
            }
          }

}

/*
** This routine does per-connection function registration.  Most
** of the built-in functions above are part of the global function set.
** This routine only deals with those that are not global.
*/
void sqlite3RegisterBuiltinFunctions(sqlite3 *db){
  int rc = sqlite3_overload_function(db, "MATCH", 2);
  assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
  if( rc==SQLITE_NOMEM ){
    sqlite3OomFault(db);
  }
}

/*
** Set the LIKEOPT flag on the 2-argument function with the given name.
*/
static void setLikeOptFlag(sqlite3 *db, const char *zName, u8 flagVal){
  FuncDef *pDef;
  pDef = sqlite3FindFunction(db, zName, sqlite3Strlen30(zName),
                             2, SQLITE_UTF8, 0);
  if( ALWAYS(pDef) ){
    pDef->funcFlags |= flagVal;
  }
}

/*
** Register the built-in LIKE and GLOB functions.  The caseSensitive

  if( pExpr->op!=TK_FUNCTION 
   || !pExpr->x.pList 
   || pExpr->x.pList->nExpr!=2
  ){
    return 0;
  }
  assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
  pDef = sqlite3FindFunction(db, pExpr->u.zToken, 
                             sqlite3Strlen30(pExpr->u.zToken),
                             2, SQLITE_UTF8, 0);
  if( NEVER(pDef==0) || (pDef->funcFlags & SQLITE_FUNC_LIKE)==0 ){
    return 0;
  }

  /* The memcpy() statement assumes that the wildcard characters are
  ** the first three statements in the compareInfo structure.  The
  ** asserts() that follow verify that assumption

/*
** All of the FuncDef structures in the aBuiltinFunc[] array above
** to the global function hash table.  This occurs at start-time (as
** a consequence of calling sqlite3_initialize()).
**
** After this routine runs
*/
void sqlite3RegisterGlobalFunctions(void){
  /*
  ** The following array holds FuncDef structures for all of the functions
  ** defined in this file.
  **
  ** The array cannot be constant since changes are made to the
  ** FuncDef.pHash elements at start-time.  The elements of this array
  ** are read-only after initialization is complete.


  */
  static SQLITE_WSD FuncDef aBuiltinFunc[] = {

















    FUNCTION(ltrim,              1, 1, 0, trimFunc         ),
    FUNCTION(ltrim,              2, 1, 0, trimFunc         ),
    FUNCTION(rtrim,              1, 2, 0, trimFunc         ),
    FUNCTION(rtrim,              2, 2, 0, trimFunc         ),
    FUNCTION(trim,               1, 3, 0, trimFunc         ),
    FUNCTION(trim,               2, 3, 0, trimFunc         ),
    FUNCTION(min,               -1, 0, 1, minmaxFunc       ),
    FUNCTION(min,                0, 0, 1, 0                ),
    AGGREGATE2(min,              1, 0, 1, minmaxStep,      minMaxFinalize,
                                          SQLITE_FUNC_MINMAX ),
    FUNCTION(max,               -1, 1, 1, minmaxFunc       ),
    FUNCTION(max,                0, 1, 1, 0                ),
    AGGREGATE2(max,              1, 1, 1, minmaxStep,      minMaxFinalize,
                                          SQLITE_FUNC_MINMAX ),
    FUNCTION2(typeof,            1, 0, 0, typeofFunc,  SQLITE_FUNC_TYPEOF),
    FUNCTION2(length,            1, 0, 0, lengthFunc,  SQLITE_FUNC_LENGTH),
    FUNCTION(instr,              2, 0, 0, instrFunc        ),
    FUNCTION(substr,             2, 0, 0, substrFunc       ),
    FUNCTION(substr,             3, 0, 0, substrFunc       ),
    FUNCTION(printf,            -1, 0, 0, printfFunc       ),
    FUNCTION(unicode,            1, 0, 0, unicodeFunc      ),
    FUNCTION(char,              -1, 0, 0, charFunc         ),
    FUNCTION(abs,                1, 0, 0, absFunc          ),
#ifndef SQLITE_OMIT_FLOATING_POINT
    FUNCTION(round,              1, 0, 0, roundFunc        ),
    FUNCTION(round,              2, 0, 0, roundFunc        ),
#endif
    FUNCTION(upper,              1, 0, 0, upperFunc        ),
    FUNCTION(lower,              1, 0, 0, lowerFunc        ),
    FUNCTION(coalesce,           1, 0, 0, 0                ),
    FUNCTION(coalesce,           0, 0, 0, 0                ),
    FUNCTION2(coalesce,         -1, 0, 0, noopFunc,  SQLITE_FUNC_COALESCE),
    FUNCTION(hex,                1, 0, 0, hexFunc          ),
    FUNCTION2(ifnull,            2, 0, 0, noopFunc,  SQLITE_FUNC_COALESCE),
    FUNCTION2(unlikely,          1, 0, 0, noopFunc,  SQLITE_FUNC_UNLIKELY),
    FUNCTION2(likelihood,        2, 0, 0, noopFunc,  SQLITE_FUNC_UNLIKELY),
    FUNCTION2(likely,            1, 0, 0, noopFunc,  SQLITE_FUNC_UNLIKELY),
    VFUNCTION(random,            0, 0, 0, randomFunc       ),
    VFUNCTION(randomblob,        1, 0, 0, randomBlob       ),
    FUNCTION(nullif,             2, 0, 1, nullifFunc       ),
    DFUNCTION(sqlite_version,    0, 0, 0, versionFunc      ),
    DFUNCTION(sqlite_source_id,  0, 0, 0, sourceidFunc     ),
    FUNCTION(sqlite_log,         2, 0, 0, errlogFunc       ),
#if SQLITE_USER_AUTHENTICATION
    FUNCTION(sqlite_crypt,       2, 0, 0, sqlite3CryptFunc ),
#endif
#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
    DFUNCTION(sqlite_compileoption_used,1, 0, 0, compileoptionusedFunc  ),
    DFUNCTION(sqlite_compileoption_get, 1, 0, 0, compileoptiongetFunc  ),
#endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */
    FUNCTION(quote,              1, 0, 0, quoteFunc        ),
    VFUNCTION(last_insert_rowid, 0, 0, 0, last_insert_rowid),
    VFUNCTION(changes,           0, 0, 0, changes          ),
    VFUNCTION(total_changes,     0, 0, 0, total_changes    ),
    FUNCTION(replace,            3, 0, 0, replaceFunc      ),
    FUNCTION(zeroblob,           1, 0, 0, zeroblobFunc     ),
  #ifdef SQLITE_SOUNDEX
    FUNCTION(soundex,            1, 0, 0, soundexFunc      ),
  #endif
  #ifndef SQLITE_OMIT_LOAD_EXTENSION
    VFUNCTION(load_extension,    1, 0, 0, loadExt          ),
    VFUNCTION(load_extension,    2, 0, 0, loadExt          ),
  #endif
    AGGREGATE(sum,               1, 0, 0, sumStep,         sumFinalize    ),
    AGGREGATE(total,             1, 0, 0, sumStep,         totalFinalize    ),
    AGGREGATE(avg,               1, 0, 0, sumStep,         avgFinalize    ),
    AGGREGATE2(count,            0, 0, 0, countStep,       countFinalize,
               SQLITE_FUNC_COUNT  ),
    AGGREGATE(count,             1, 0, 0, countStep,       countFinalize  ),
    AGGREGATE(group_concat,      1, 0, 0, groupConcatStep, groupConcatFinalize),
    AGGREGATE(group_concat,      2, 0, 0, groupConcatStep, groupConcatFinalize),
  
    LIKEFUNC(glob, 2, &globInfo, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
  #ifdef SQLITE_CASE_SENSITIVE_LIKE
    LIKEFUNC(like, 2, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
    LIKEFUNC(like, 3, &likeInfoAlt, SQLITE_FUNC_LIKE|SQLITE_FUNC_CASE),
  #else
    LIKEFUNC(like, 2, &likeInfoNorm, SQLITE_FUNC_LIKE),
    LIKEFUNC(like, 3, &likeInfoNorm, SQLITE_FUNC_LIKE),
  #endif
  };

  int i;
  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aBuiltinFunc);

  for(i=0; i<ArraySize(aBuiltinFunc); i++){
    sqlite3FuncDefInsert(pHash, &aFunc[i]);

  }
  sqlite3RegisterDateTimeFunctions();
#ifndef SQLITE_OMIT_ALTERTABLE
  sqlite3AlterFunctions();
#endif
#if defined(SQLITE_ENABLE_STAT3) || defined(SQLITE_ENABLE_STAT4)
  sqlite3AnalyzeFunctions();
#endif


}

};

/*
** Hash table for global functions - functions common to all
** database connections.  After initialization, this table is
** read-only.
*/
SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;

/*
** Constant tokens for values 0 and 1.
*/
const Token sqlite3IntTokens[] = {
   { "0", 1 },
   { "1", 1 }

  **
  ** The following mutex is what serializes access to the appdef pcache xInit
  ** methods.  The sqlite3_pcache_methods.xInit() all is embedded in the
  ** call to sqlite3PcacheInitialize().
  */
  sqlite3_mutex_enter(sqlite3GlobalConfig.pInitMutex);
  if( sqlite3GlobalConfig.isInit==0 && sqlite3GlobalConfig.inProgress==0 ){
    FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
    sqlite3GlobalConfig.inProgress = 1;
#ifdef SQLITE_ENABLE_SQLLOG
    {
      extern void sqlite3_init_sqllog(void);
      sqlite3_init_sqllog();
    }
#endif
    memset(pHash, 0, sizeof(sqlite3GlobalFunctions));
    sqlite3RegisterGlobalFunctions();
    if( sqlite3GlobalConfig.isPCacheInit==0 ){
      rc = sqlite3PcacheInitialize();
    }
    if( rc==SQLITE_OK ){
      sqlite3GlobalConfig.isPCacheInit = 1;
      rc = sqlite3OsInit();
    }

/*
** Invoke the destructor function associated with FuncDef p, if any. Except,
** if this is not the last copy of the function, do not invoke it. Multiple
** copies of a single function are created when create_function() is called
** with SQLITE_ANY as the encoding.
*/
static void functionDestroy(sqlite3 *db, FuncDef *p){
  FuncDestructor *pDestructor = p->pDestructor;
  if( pDestructor ){
    pDestructor->nRef--;
    if( pDestructor->nRef==0 ){
      pDestructor->xDestroy(pDestructor->pUserData);
      sqlite3DbFree(db, pDestructor);
    }
  }

  assert( db->aDb==db->aDbStatic );

  /* Tell the code in notify.c that the connection no longer holds any
  ** locks and does not require any further unlock-notify callbacks.
  */
  sqlite3ConnectionClosed(db);

  for(j=0; j<ArraySize(db->aFunc.a); j++){
    FuncDef *pNext, *pHash, *p;
    for(p=db->aFunc.a[j]; p; p=pHash){
      pHash = p->pHash;
      while( p ){

        functionDestroy(db, p);
        pNext = p->pNext;
        sqlite3DbFree(db, p);
        p = pNext;
      }
    }
  }

  for(i=sqliteHashFirst(&db->aCollSeq); i; i=sqliteHashNext(i)){
    CollSeq *pColl = (CollSeq *)sqliteHashData(i);
    /* Invoke any destructors registered for collation sequence user data. */
    for(j=0; j<3; j++){
      if( pColl[j].xDel ){
        pColl[j].xDel(pColl[j].pUser);
      }

#endif
  
  /* Check if an existing function is being overridden or deleted. If so,
  ** and there are active VMs, then return SQLITE_BUSY. If a function
  ** is being overridden/deleted but there are no active VMs, allow the
  ** operation to continue but invalidate all precompiled statements.
  */
  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, (u8)enc, 0);
  if( p && (p->funcFlags & SQLITE_FUNC_ENCMASK)==enc && p->nArg==nArg ){
    if( db->nVdbeActive ){
      sqlite3ErrorWithMsg(db, SQLITE_BUSY, 
        "unable to delete/modify user-function due to active statements");
      assert( !db->mallocFailed );
      return SQLITE_BUSY;
    }else{
      sqlite3ExpirePreparedStatements(db);
    }
  }

  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, (u8)enc, 1);
  assert(p || db->mallocFailed);
  if( !p ){
    return SQLITE_NOMEM;
  }

  /* If an older version of the function with a configured destructor is
  ** being replaced invoke the destructor function here. */
  functionDestroy(db, p);

  if( pDestructor ){
    pDestructor->nRef++;
  }
  p->pDestructor = pDestructor;
  p->funcFlags = (p->funcFlags & SQLITE_FUNC_ENCMASK) | extraFlags;
  testcase( p->funcFlags & SQLITE_DETERMINISTIC );
  p->xSFunc = xSFunc ? xSFunc : xStep;
  p->xFinalize = xFinal;
  p->pUserData = pUserData;
  p->nArg = (u16)nArg;
  return SQLITE_OK;

** properly.
*/
int sqlite3_overload_function(
  sqlite3 *db,
  const char *zName,
  int nArg
){
  int nName = sqlite3Strlen30(zName);
  int rc = SQLITE_OK;

#ifdef SQLITE_ENABLE_API_ARMOR
  if( !sqlite3SafetyCheckOk(db) || zName==0 || nArg<-2 ){
    return SQLITE_MISUSE_BKPT;
  }
#endif
  sqlite3_mutex_enter(db->mutex);
  if( sqlite3FindFunction(db, zName, nName, nArg, SQLITE_UTF8, 0)==0 ){
    rc = sqlite3CreateFunc(db, zName, nArg, SQLITE_UTF8,
                           0, sqlite3InvalidFunction, 0, 0, 0);
  }
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

#endif
#if SQLITE_MAX_COMPOUND_SELECT<2
# error SQLITE_MAX_COMPOUND_SELECT must be at least 2
#endif
#if SQLITE_MAX_VDBE_OP<40
# error SQLITE_MAX_VDBE_OP must be at least 40
#endif
#if SQLITE_MAX_FUNCTION_ARG<0 || SQLITE_MAX_FUNCTION_ARG>1000
# error SQLITE_MAX_FUNCTION_ARG must be between 0 and 1000
#endif
#if SQLITE_MAX_ATTACHED<0 || SQLITE_MAX_ATTACHED>125
# error SQLITE_MAX_ATTACHED must be between 0 and 125
#endif
#if SQLITE_MAX_LIKE_PATTERN_LENGTH<1
# error SQLITE_MAX_LIKE_PATTERN_LENGTH must be at least 1
#endif

  }

  /* Register all built-in functions, but do not attempt to read the
  ** database schema yet. This is delayed until the first time the database
  ** is accessed.
  */
  sqlite3Error(db, SQLITE_OK);
  sqlite3RegisterBuiltinFunctions(db);

  /* Load automatic extensions - extensions that have been registered
  ** using the sqlite3_automatic_extension() API.
  */
  rc = sqlite3_errcode(db);
  if( rc==SQLITE_OK ){
    sqlite3AutoLoadExtensions(db);

      FuncDef *pDef;              /* Information about the function */
      u8 enc = ENC(pParse->db);   /* The database encoding */

      assert( !ExprHasProperty(pExpr, EP_xIsSelect) );
      notValid(pParse, pNC, "functions", NC_PartIdx);
      zId = pExpr->u.zToken;
      nId = sqlite3Strlen30(zId);
      pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0);
      if( pDef==0 ){
        pDef = sqlite3FindFunction(pParse->db, zId, nId, -2, enc, 0);
        if( pDef==0 ){
          no_such_func = 1;
        }else{
          wrong_num_args = 1;
        }
      }else{
        is_agg = pDef->xFinalize!=0;

  void *pEnd;             /* First byte past end of available space */
};
struct LookasideSlot {
  LookasideSlot *pNext;    /* Next buffer in the list of free buffers */
};

/*
** A hash table for function definitions.

**
** Hash each FuncDef structure into one of the FuncDefHash.a[] slots.
** Collisions are on the FuncDef.pHash chain.
*/

struct FuncDefHash {
  FuncDef *a[23];       /* Hash table for functions */
};

#ifdef SQLITE_USER_AUTHENTICATION
/*
** Information held in the "sqlite3" database connection object and used
** to manage user authentication.
*/

#ifndef SQLITE_OMIT_VIRTUALTABLE
  int nVTrans;                  /* Allocated size of aVTrans */
  Hash aModule;                 /* populated by sqlite3_create_module() */
  VtabCtx *pVtabCtx;            /* Context for active vtab connect/create */
  VTable **aVTrans;             /* Virtual tables with open transactions */
  VTable *pDisconnect;    /* Disconnect these in next sqlite3_prepare() */
#endif
  FuncDefHash aFunc;            /* Hash table of connection functions */
  Hash aCollSeq;                /* All collating sequences */
  BusyHandler busyHandler;      /* Busy callback */
  Db aDbStatic[2];              /* Static space for the 2 default backends */
  Savepoint *pSavepoint;        /* List of active savepoints */
  int busyTimeout;              /* Busy handler timeout, in msec */
  int nSavepoint;               /* Number of non-transaction savepoints */
  int nStatement;               /* Number of nested statement-transactions  */

#define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
#define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
#define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */
#define SQLITE_MAGIC_ZOMBIE   0x64cffc7f  /* Close with last statement close */

/*
** Each SQL function is defined by an instance of the following

** structure.  A pointer to this structure is stored in the sqlite.aFunc
** hash table.  When multiple functions have the same name, the hash table
** points to a linked list of these structures.



*/
struct FuncDef {
  i16 nArg;            /* Number of arguments.  -1 means unlimited */
  u16 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 */
  char *zName;         /* SQL name of the function. */

  FuncDef *pHash;      /* Next with a different name but the same hash */
  FuncDestructor *pDestructor;   /* Reference counted destructor function */

};

/*
** 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 

**     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_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, 0, 0}
#define VFUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, 0, 0}
#define DFUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, 0, 0}
#define FUNCTION2(zName, nArg, iArg, bNC, xFunc, extraFlags) \
  {nArg,SQLITE_FUNC_CONSTANT|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL)|extraFlags,\
   SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, #zName, 0, 0}
#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
  {nArg, SQLITE_FUNC_SLOCHNG|SQLITE_UTF8|(bNC*SQLITE_FUNC_NEEDCOLL), \
   pArg, 0, xFunc, 0, #zName, 0, 0}
#define LIKEFUNC(zName, nArg, arg, flags) \
  {nArg, SQLITE_FUNC_CONSTANT|SQLITE_UTF8|flags, \
   (void *)arg, 0, likeFunc, 0, #zName, 0, 0}
#define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
  {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL), \
   SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,#zName,0,0}
#define AGGREGATE2(zName, nArg, arg, nc, xStep, xFinal, extraFlags) \
  {nArg, SQLITE_UTF8|(nc*SQLITE_FUNC_NEEDCOLL)|extraFlags, \
   SQLITE_INT_TO_PTR(arg), 0, xStep,xFinal,#zName,0,0}

/*
** 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.
*/

#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS
int sqlite3IsIdChar(u8);
#endif

/*
** Internal function prototypes
*/
#define sqlite3StrICmp sqlite3_stricmp
int sqlite3Strlen30(const char*);
#define sqlite3StrNICmp sqlite3_strnicmp

int sqlite3MallocInit(void);
void sqlite3MallocEnd(void);
void *sqlite3Malloc(u64);
void *sqlite3MallocZero(u64);

IdList *sqlite3IdListDup(sqlite3*,IdList*);
Select *sqlite3SelectDup(sqlite3*,Select*,int);
#if SELECTTRACE_ENABLED
void sqlite3SelectSetName(Select*,const char*);
#else
# define sqlite3SelectSetName(A,B)
#endif
void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
void sqlite3RegisterBuiltinFunctions(sqlite3*);
void sqlite3RegisterDateTimeFunctions(void);
void sqlite3RegisterGlobalFunctions(void);
int sqlite3SafetyCheckOk(sqlite3*);
int sqlite3SafetyCheckSickOrOk(sqlite3*);
void sqlite3ChangeCookie(Parse*, int);

#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
void sqlite3MaterializeView(Parse*, Table*, Expr*, int);
#endif

#ifndef SQLITE_AMALGAMATION
extern const unsigned char sqlite3OpcodeProperty[];
extern const char sqlite3StrBINARY[];
extern const unsigned char sqlite3UpperToLower[];
extern const unsigned char sqlite3CtypeMap[];
extern const Token sqlite3IntTokens[];
extern SQLITE_WSD struct Sqlite3Config sqlite3Config;
extern SQLITE_WSD FuncDefHash sqlite3GlobalFunctions;
#ifndef SQLITE_OMIT_WSD
extern int sqlite3PendingByte;
#endif
#endif
void sqlite3RootPageMoved(sqlite3*, int, int, int);
void sqlite3Reindex(Parse*, Token*, Token*);
void sqlite3AlterFunctions(void);

** IMPLEMENTATION-OF: R-30243-02494 The sqlite3_stricmp() and
** sqlite3_strnicmp() APIs allow applications and extensions to compare
** the contents of two buffers containing UTF-8 strings in a
** case-independent fashion, using the same definition of "case
** independence" that SQLite uses internally when comparing identifiers.
*/
int sqlite3_stricmp(const char *zLeft, const char *zRight){
  register unsigned char *a, *b;
  if( zLeft==0 ){
    return zRight ? -1 : 0;
  }else if( zRight==0 ){
    return 1;
  }





  a = (unsigned char *)zLeft;
  b = (unsigned char *)zRight;

  while( *a!=0 && UpperToLower[*a]==UpperToLower[*b]){ a++; b++; }




  return UpperToLower[*a] - UpperToLower[*b];
}
int sqlite3_strnicmp(const char *zLeft, const char *zRight, int N){
  register unsigned char *a, *b;
  if( zLeft==0 ){
    return zRight ? -1 : 0;
  }else if( zRight==0 ){
    return 1;

){
  sqlite3_context ctx;            /* Context object for function invocation */
  sqlite3_value **apVal = 0;      /* Function arguments */
  int nVal = 0;                   /* Size of apVal[] array */
  FuncDef *pFunc = 0;             /* Function definition */
  sqlite3_value *pVal = 0;        /* New value */
  int rc = SQLITE_OK;             /* Return code */
  int nName;                      /* Size of function name in bytes */
  ExprList *pList = 0;            /* Function arguments */
  int i;                          /* Iterator variable */

  assert( pCtx!=0 );
  assert( (p->flags & EP_TokenOnly)==0 );
  pList = p->x.pList;
  if( pList ) nVal = pList->nExpr;
  nName = sqlite3Strlen30(p->u.zToken);
  pFunc = sqlite3FindFunction(db, p->u.zToken, nName, nVal, enc, 0);
  assert( pFunc );
  if( (pFunc->funcFlags & (SQLITE_FUNC_CONSTANT|SQLITE_FUNC_SLOCHNG))==0 
   || (pFunc->funcFlags & SQLITE_FUNC_NEEDCOLL)
  ){
    return SQLITE_OK;
  }

  }
}

/*
** Register built-in functions used to help read ANALYZE data.
*/
void sqlite3AnalyzeFunctions(void){
  static SQLITE_WSD FuncDef aAnalyzeTableFuncs[] = {
    FUNCTION(sqlite_record,   1, 0, 0, recordFunc),
  };
  int i;
  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aAnalyzeTableFuncs);
  for(i=0; i<ArraySize(aAnalyzeTableFuncs); i++){
    sqlite3FuncDefInsert(pHash, &aFunc[i]);
  }
}

/*
** Attempt to extract a value from pExpr and use it to construct *ppVal.
**
** If pAlloc is not NULL, then an UnpackedRecord object is created for
** pAlloc if one does not exist and the new value is added to the