}
    zK2 = (char*)phoneticHash((const unsigned char*)zK1, i);
    if( zK2==0 ){
      sqlite3_free(zK1);
      return SQLITE_NOMEM;
    }
    if( sqlite3_value_type(argv[0])==SQLITE_NULL ){

      spellfix1DbExec(&rc, db,
             "INSERT INTO \"%w\".\"%w_vocab\"(rank,langid,word,k1,k2) "
             "VALUES(%d,%d,%Q,%Q,%Q)",
             p->zDbName, p->zTableName,
             iRank, iLang, zWord, zK1, zK2
      );









      *pRowid = sqlite3_last_insert_rowid(db);
    }else{
      rowid = sqlite3_value_int64(argv[0]);
      newRowid = *pRowid = sqlite3_value_int64(argv[1]);
      spellfix1DbExec(&rc, db,
             "UPDATE \"%w\".\"%w_vocab\" SET id=%lld, rank=%d, langid=%d,"
             " word=%Q, k1=%Q, k2=%Q WHERE id=%lld",

    }
    zK2 = (char*)phoneticHash((const unsigned char*)zK1, i);
    if( zK2==0 ){
      sqlite3_free(zK1);
      return SQLITE_NOMEM;
    }
    if( sqlite3_value_type(argv[0])==SQLITE_NULL ){
      if( sqlite3_value_type(argv[1])==SQLITE_NULL ){
        spellfix1DbExec(&rc, db,
               "INSERT INTO \"%w\".\"%w_vocab\"(rank,langid,word,k1,k2) "
               "VALUES(%d,%d,%Q,%Q,%Q)",
               p->zDbName, p->zTableName,
               iRank, iLang, zWord, zK1, zK2
        );
      }else{
        newRowid = sqlite3_value_int64(argv[1]);
        spellfix1DbExec(&rc, db,
               "INSERT INTO \"%w\".\"%w_vocab\"(id,rank,langid,word,k1,k2) "
               "VALUES(%lld,%d,%d,%Q,%Q,%Q)",
               p->zDbName, p->zTableName,
               newRowid, iRank, iLang, zWord, zK1, zK2
        );
      }
      *pRowid = sqlite3_last_insert_rowid(db);
    }else{
      rowid = sqlite3_value_int64(argv[0]);
      newRowid = *pRowid = sqlite3_value_int64(argv[1]);
      spellfix1DbExec(&rc, db,
             "UPDATE \"%w\".\"%w_vocab\" SET id=%lld, rank=%d, langid=%d,"
             " word=%Q, k1=%Q, k2=%Q WHERE id=%lld",

  int i = sqlite3FindDbName(pDb, zDb);

  if( i==1 ){
    Parse *pParse;
    int rc = 0;
    pParse = sqlite3StackAllocZero(pErrorDb, sizeof(*pParse));
    if( pParse==0 ){
      sqlite3Error(pErrorDb, SQLITE_NOMEM, "out of memory");
      rc = SQLITE_NOMEM;
    }else{
      pParse->db = pDb;
      if( sqlite3OpenTempDatabase(pParse) ){
        sqlite3Error(pErrorDb, pParse->rc, "%s", pParse->zErrMsg);
        rc = SQLITE_ERROR;
      }
      sqlite3DbFree(pErrorDb, pParse->zErrMsg);
      sqlite3ParserReset(pParse);
      sqlite3StackFree(pErrorDb, pParse);
    }
    if( rc ){
      return 0;
    }
  }

  if( i<0 ){
    sqlite3Error(pErrorDb, SQLITE_ERROR, "unknown database %s", zDb);
    return 0;
  }

  return pDb->aDb[i].pBt;
}

/*
................................................................................
  ** database connection while a backup is in progress may cause
  ** a malfunction or a deadlock.
  */
  sqlite3_mutex_enter(pSrcDb->mutex);
  sqlite3_mutex_enter(pDestDb->mutex);

  if( pSrcDb==pDestDb ){
    sqlite3Error(
        pDestDb, SQLITE_ERROR, "source and destination must be distinct"
    );
    p = 0;
  }else {
    /* Allocate space for a new sqlite3_backup object...
    ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
    ** call to sqlite3_backup_init() and is destroyed by a call to
    ** sqlite3_backup_finish(). */
    p = (sqlite3_backup *)sqlite3MallocZero(sizeof(sqlite3_backup));
    if( !p ){
      sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
    }
  }

  /* If the allocation succeeded, populate the new object. */
  if( p ){
    p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
    p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
................................................................................

  /* If a transaction is still open on the Btree, roll it back. */
  sqlite3BtreeRollback(p->pDest, SQLITE_OK);

  /* Set the error code of the destination database handle. */
  rc = (p->rc==SQLITE_DONE) ? SQLITE_OK : p->rc;
  if( p->pDestDb ){
    sqlite3Error(p->pDestDb, rc, 0);

    /* Exit the mutexes and free the backup context structure. */
    sqlite3LeaveMutexAndCloseZombie(p->pDestDb);
  }
  sqlite3BtreeLeave(p->pSrc);
  if( p->pDestDb ){
    /* EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a

  int i = sqlite3FindDbName(pDb, zDb);

  if( i==1 ){
    Parse *pParse;
    int rc = 0;
    pParse = sqlite3StackAllocZero(pErrorDb, sizeof(*pParse));
    if( pParse==0 ){
      sqlite3ErrorWithMsg(pErrorDb, SQLITE_NOMEM, "out of memory");
      rc = SQLITE_NOMEM;
    }else{
      pParse->db = pDb;
      if( sqlite3OpenTempDatabase(pParse) ){
        sqlite3ErrorWithMsg(pErrorDb, pParse->rc, "%s", pParse->zErrMsg);
        rc = SQLITE_ERROR;
      }
      sqlite3DbFree(pErrorDb, pParse->zErrMsg);
      sqlite3ParserReset(pParse);
      sqlite3StackFree(pErrorDb, pParse);
    }
    if( rc ){
      return 0;
    }
  }

  if( i<0 ){
    sqlite3ErrorWithMsg(pErrorDb, SQLITE_ERROR, "unknown database %s", zDb);
    return 0;
  }

  return pDb->aDb[i].pBt;
}

/*
................................................................................
  ** database connection while a backup is in progress may cause
  ** a malfunction or a deadlock.
  */
  sqlite3_mutex_enter(pSrcDb->mutex);
  sqlite3_mutex_enter(pDestDb->mutex);

  if( pSrcDb==pDestDb ){
    sqlite3ErrorWithMsg(
        pDestDb, SQLITE_ERROR, "source and destination must be distinct"
    );
    p = 0;
  }else {
    /* Allocate space for a new sqlite3_backup object...
    ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
    ** call to sqlite3_backup_init() and is destroyed by a call to
    ** sqlite3_backup_finish(). */
    p = (sqlite3_backup *)sqlite3MallocZero(sizeof(sqlite3_backup));
    if( !p ){
      sqlite3Error(pDestDb, SQLITE_NOMEM);
    }
  }

  /* If the allocation succeeded, populate the new object. */
  if( p ){
    p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
    p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
................................................................................

  /* If a transaction is still open on the Btree, roll it back. */
  sqlite3BtreeRollback(p->pDest, SQLITE_OK);

  /* Set the error code of the destination database handle. */
  rc = (p->rc==SQLITE_DONE) ? SQLITE_OK : p->rc;
  if( p->pDestDb ){
    sqlite3Error(p->pDestDb, rc);

    /* Exit the mutexes and free the backup context structure. */
    sqlite3LeaveMutexAndCloseZombie(p->pDestDb);
  }
  sqlite3BtreeLeave(p->pSrc);
  if( p->pDestDb ){
    /* EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a

  p->locked = 1;
}

/*
** Release the BtShared mutex associated with B-Tree handle p and
** clear the p->locked boolean.
*/
static void unlockBtreeMutex(Btree *p){
  BtShared *pBt = p->pBt;
  assert( p->locked==1 );
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( sqlite3_mutex_held(p->db->mutex) );
  assert( p->db==pBt->db );

  sqlite3_mutex_leave(pBt->mutex);
  p->locked = 0;
}




/*
** Enter a mutex on the given BTree object.
**
** If the object is not sharable, then no mutex is ever required
** and this routine is a no-op.  The underlying mutex is non-recursive.
** But we keep a reference count in Btree.wantToLock so the behavior
** of this interface is recursive.
................................................................................
** Btrees belonging to the same database connection as the p Btree
** which need to be locked after p.  If we cannot get a lock on
** p, then first unlock all of the others on p->pNext, then wait
** for the lock to become available on p, then relock all of the
** subsequent Btrees that desire a lock.
*/
void sqlite3BtreeEnter(Btree *p){
  Btree *pLater;

  /* Some basic sanity checking on the Btree.  The list of Btrees
  ** connected by pNext and pPrev should be in sorted order by
  ** Btree.pBt value. All elements of the list should belong to
  ** the same connection. Only shared Btrees are on the list. */
  assert( p->pNext==0 || p->pNext->pBt>p->pBt );
  assert( p->pPrev==0 || p->pPrev->pBt<p->pBt );
  assert( p->pNext==0 || p->pNext->db==p->db );
................................................................................
  /* Unless the database is sharable and unlocked, then BtShared.db
  ** should already be set correctly. */
  assert( (p->locked==0 && p->sharable) || p->pBt->db==p->db );

  if( !p->sharable ) return;
  p->wantToLock++;
  if( p->locked ) return;












  /* In most cases, we should be able to acquire the lock we
  ** want without having to go throught the ascending lock
  ** procedure that follows.  Just be sure not to block.
  */
  if( sqlite3_mutex_try(p->pBt->mutex)==SQLITE_OK ){
    p->pBt->db = p->db;
................................................................................
  lockBtreeMutex(p);
  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
    if( pLater->wantToLock ){
      lockBtreeMutex(pLater);
    }
  }
}


/*
** Exit the recursive mutex on a Btree.
*/
void sqlite3BtreeLeave(Btree *p){
  if( p->sharable ){
    assert( p->wantToLock>0 );

  p->locked = 1;
}

/*
** Release the BtShared mutex associated with B-Tree handle p and
** clear the p->locked boolean.
*/
static void SQLITE_NOINLINE unlockBtreeMutex(Btree *p){
  BtShared *pBt = p->pBt;
  assert( p->locked==1 );
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( sqlite3_mutex_held(p->db->mutex) );
  assert( p->db==pBt->db );

  sqlite3_mutex_leave(pBt->mutex);
  p->locked = 0;
}

/* Forward reference */
static void SQLITE_NOINLINE btreeLockCarefully(Btree *p);

/*
** Enter a mutex on the given BTree object.
**
** If the object is not sharable, then no mutex is ever required
** and this routine is a no-op.  The underlying mutex is non-recursive.
** But we keep a reference count in Btree.wantToLock so the behavior
** of this interface is recursive.
................................................................................
** Btrees belonging to the same database connection as the p Btree
** which need to be locked after p.  If we cannot get a lock on
** p, then first unlock all of the others on p->pNext, then wait
** for the lock to become available on p, then relock all of the
** subsequent Btrees that desire a lock.
*/
void sqlite3BtreeEnter(Btree *p){


  /* Some basic sanity checking on the Btree.  The list of Btrees
  ** connected by pNext and pPrev should be in sorted order by
  ** Btree.pBt value. All elements of the list should belong to
  ** the same connection. Only shared Btrees are on the list. */
  assert( p->pNext==0 || p->pNext->pBt>p->pBt );
  assert( p->pPrev==0 || p->pPrev->pBt<p->pBt );
  assert( p->pNext==0 || p->pNext->db==p->db );
................................................................................
  /* Unless the database is sharable and unlocked, then BtShared.db
  ** should already be set correctly. */
  assert( (p->locked==0 && p->sharable) || p->pBt->db==p->db );

  if( !p->sharable ) return;
  p->wantToLock++;
  if( p->locked ) return;
  btreeLockCarefully(p);
}

/* This is a helper function for sqlite3BtreeLock(). By moving
** complex, but seldom used logic, out of sqlite3BtreeLock() and
** into this routine, we avoid unnecessary stack pointer changes
** and thus help the sqlite3BtreeLock() routine to run much faster
** in the common case.
*/
static void SQLITE_NOINLINE btreeLockCarefully(Btree *p){
  Btree *pLater;

  /* In most cases, we should be able to acquire the lock we
  ** want without having to go throught the ascending lock
  ** procedure that follows.  Just be sure not to block.
  */
  if( sqlite3_mutex_try(p->pBt->mutex)==SQLITE_OK ){
    p->pBt->db = p->db;
................................................................................
  lockBtreeMutex(p);
  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
    if( pLater->wantToLock ){
      lockBtreeMutex(pLater);
    }
  }
}


/*
** Exit the recursive mutex on a Btree.
*/
void sqlite3BtreeLeave(Btree *p){
  if( p->sharable ){
    assert( p->wantToLock>0 );

    pCur->eState = CURSOR_REQUIRESEEK;
  }

  invalidateOverflowCache(pCur);
  return rc;
}




/*
** Save the positions of all cursors (except pExcept) that are open on



** the table  with root-page iRoot. Usually, this is called just before cursor
** pExcept is used to modify the table (BtreeDelete() or BtreeInsert()).




*/
static int saveAllCursors(BtShared *pBt, Pgno iRoot, BtCursor *pExcept){
  BtCursor *p;
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( pExcept==0 || pExcept->pBt==pBt );
  for(p=pBt->pCursor; p; p=p->pNext){
















    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) ){
      if( p->eState==CURSOR_VALID ){
        int rc = saveCursorPosition(p);
        if( SQLITE_OK!=rc ){
          return rc;
        }
      }else{
        testcase( p->iPage>0 );
        btreeReleaseAllCursorPages(p);
      }
    }
  }

  return SQLITE_OK;
}

/*
** Clear the current cursor position.
*/
void sqlite3BtreeClearCursor(BtCursor *pCur){
................................................................................

#define restoreCursorPosition(p) \
  (p->eState>=CURSOR_REQUIRESEEK ? \
         btreeRestoreCursorPosition(p) : \
         SQLITE_OK)

/*
** Determine whether or not a cursor has moved from the position it

** was last placed at.  Cursors can move when the row they are pointing
** at is deleted out from under them.


**
** This routine returns an error code if something goes wrong.  The
** integer *pHasMoved is set as follows:

**
**    0:   The cursor is unchanged
**    1:   The cursor is still pointing at the same row, but the pointers
**         returned by sqlite3BtreeKeyFetch() or sqlite3BtreeDataFetch()
**         might now be invalid because of a balance() or other change to the
**         b-tree.
**    2:   The cursor is no longer pointing to the row.  The row might have





**         been deleted out from under the cursor.
*/






int sqlite3BtreeCursorHasMoved(BtCursor *pCur, int *pHasMoved){


  int rc;


  if( pCur->eState==CURSOR_VALID ){
    *pHasMoved = 0;
    return SQLITE_OK;
  }
  rc = restoreCursorPosition(pCur);
  if( rc ){
    *pHasMoved = 2;

    return rc;
  }
  if( pCur->eState!=CURSOR_VALID || NEVER(pCur->skipNext!=0) ){
    *pHasMoved = 2;
  }else{
    *pHasMoved = 1;
  }
  return SQLITE_OK;
}

#ifndef SQLITE_OMIT_AUTOVACUUM
/*
** Given a page number of a regular database page, return the page

    pCur->eState = CURSOR_REQUIRESEEK;
  }

  invalidateOverflowCache(pCur);
  return rc;
}

/* Forward reference */
static int SQLITE_NOINLINE saveCursorsOnList(BtCursor*,Pgno,BtCursor*);

/*
** Save the positions of all cursors (except pExcept) that are open on
** the table with root-page iRoot.  "Saving the cursor position" means that
** the location in the btree is remembered in such a way that it can be
** moved back to the same spot after the btree has been modified.  This
** routine is called just before cursor pExcept is used to modify the
** table, for example in BtreeDelete() or BtreeInsert().
**
** Implementation note:  This routine merely checks to see if any cursors
** need to be saved.  It calls out to saveCursorsOnList() in the (unusual)
** event that cursors are in need to being saved.
*/
static int saveAllCursors(BtShared *pBt, Pgno iRoot, BtCursor *pExcept){
  BtCursor *p;
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( pExcept==0 || pExcept->pBt==pBt );
  for(p=pBt->pCursor; p; p=p->pNext){
    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) ) break;
  }
  return p ? saveCursorsOnList(p, iRoot, pExcept) : SQLITE_OK;
}

/* This helper routine to saveAllCursors does the actual work of saving
** the cursors if and when a cursor is found that actually requires saving.
** The common case is that no cursors need to be saved, so this routine is
** broken out from its caller to avoid unnecessary stack pointer movement.
*/
static int SQLITE_NOINLINE saveCursorsOnList(
  BtCursor *p,           /* The first cursor that needs saving */
  Pgno iRoot,            /* Only save cursor with this iRoot.  Save all if zero */
  BtCursor *pExcept      /* Do not save this cursor */
){
  do{
    if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) ){
      if( p->eState==CURSOR_VALID ){
        int rc = saveCursorPosition(p);
        if( SQLITE_OK!=rc ){
          return rc;
        }
      }else{
        testcase( p->iPage>0 );
        btreeReleaseAllCursorPages(p);
      }
    }
    p = p->pNext;
  }while( p );
  return SQLITE_OK;
}

/*
** Clear the current cursor position.
*/
void sqlite3BtreeClearCursor(BtCursor *pCur){
................................................................................

#define restoreCursorPosition(p) \
  (p->eState>=CURSOR_REQUIRESEEK ? \
         btreeRestoreCursorPosition(p) : \
         SQLITE_OK)

/*
** Determine whether or not a cursor has moved from the position where
** it was last placed, or has been invalidated for any other reason.
** Cursors can move when the row they are pointing at is deleted out

** from under them, for example.  Cursor might also move if a btree
** is rebalanced.
**


** Calling this routine with a NULL cursor pointer returns false.
**

** Use the separate sqlite3BtreeCursorRestore() routine to restore a cursor
** back to where it ought to be if this routine returns true.
*/
int sqlite3BtreeCursorHasMoved(BtCursor *pCur){
  return pCur && pCur->eState!=CURSOR_VALID;
}

/*
** This routine restores a cursor back to its original position after it
** has been moved by some outside activity (such as a btree rebalance or
** a row having been deleted out from under the cursor).  
**
** On success, the *pDifferentRow parameter is false if the cursor is left
** pointing at exactly the same row.  *pDifferntRow is the row the cursor
** was pointing to has been deleted, forcing the cursor to point to some
** nearby row.
**
** This routine should only be called for a cursor that just returned
** TRUE from sqlite3BtreeCursorHasMoved().
*/
int sqlite3BtreeCursorRestore(BtCursor *pCur, int *pDifferentRow){
  int rc;

  assert( pCur!=0 );
  assert( pCur->eState!=CURSOR_VALID );



  rc = restoreCursorPosition(pCur);
  if( rc ){

    *pDifferentRow = 1;
    return rc;
  }
  if( pCur->eState!=CURSOR_VALID || NEVER(pCur->skipNext!=0) ){
    *pDifferentRow = 1;
  }else{
    *pDifferentRow = 0;
  }
  return SQLITE_OK;
}

#ifndef SQLITE_OMIT_AUTOVACUUM
/*
** Given a page number of a regular database page, return the page

int sqlite3BtreeMovetoUnpacked(
  BtCursor*,
  UnpackedRecord *pUnKey,
  i64 intKey,
  int bias,
  int *pRes
);
int sqlite3BtreeCursorHasMoved(BtCursor*, int*);

int sqlite3BtreeDelete(BtCursor*);
int sqlite3BtreeInsert(BtCursor*, const void *pKey, i64 nKey,
                                  const void *pData, int nData,
                                  int nZero, int bias, int seekResult);
int sqlite3BtreeFirst(BtCursor*, int *pRes);
int sqlite3BtreeLast(BtCursor*, int *pRes);
int sqlite3BtreeNext(BtCursor*, int *pRes);

int sqlite3BtreeMovetoUnpacked(
  BtCursor*,
  UnpackedRecord *pUnKey,
  i64 intKey,
  int bias,
  int *pRes
);
int sqlite3BtreeCursorHasMoved(BtCursor*);
int sqlite3BtreeCursorRestore(BtCursor*, int*);
int sqlite3BtreeDelete(BtCursor*);
int sqlite3BtreeInsert(BtCursor*, const void *pKey, i64 nKey,
                                  const void *pData, int nData,
                                  int nZero, int bias, int seekResult);
int sqlite3BtreeFirst(BtCursor*, int *pRes);
int sqlite3BtreeLast(BtCursor*, int *pRes);
int sqlite3BtreeNext(BtCursor*, int *pRes);

** auxiliary databases added using the ATTACH command.
**
** See also sqlite3LocateTable().
*/
Table *sqlite3FindTable(sqlite3 *db, const char *zName, const char *zDatabase){
  Table *p = 0;
  int i;
  int nName;
  assert( zName!=0 );
  nName = sqlite3Strlen30(zName);
  /* All mutexes are required for schema access.  Make sure we hold them. */
  assert( zDatabase!=0 || sqlite3BtreeHoldsAllMutexes(db) );
  for(i=OMIT_TEMPDB; i<db->nDb; i++){
    int j = (i<2) ? i^1 : i;   /* Search TEMP before MAIN */
    if( zDatabase!=0 && sqlite3StrICmp(zDatabase, db->aDb[j].zName) ) continue;
    assert( sqlite3SchemaMutexHeld(db, j, 0) );
    p = sqlite3HashFind(&db->aDb[j].pSchema->tblHash, zName, nName);
    if( p ) break;
  }
  return p;
}

/*
** Locate the in-memory structure that describes a particular database
................................................................................
** for duplicate index names is done.)  The search order is
** TEMP first, then MAIN, then any auxiliary databases added
** using the ATTACH command.
*/
Index *sqlite3FindIndex(sqlite3 *db, const char *zName, const char *zDb){
  Index *p = 0;
  int i;
  int nName = sqlite3Strlen30(zName);
  /* All mutexes are required for schema access.  Make sure we hold them. */
  assert( zDb!=0 || sqlite3BtreeHoldsAllMutexes(db) );
  for(i=OMIT_TEMPDB; i<db->nDb; i++){
    int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
    Schema *pSchema = db->aDb[j].pSchema;
    assert( pSchema );
    if( zDb && sqlite3StrICmp(zDb, db->aDb[j].zName) ) continue;
    assert( sqlite3SchemaMutexHeld(db, j, 0) );
    p = sqlite3HashFind(&pSchema->idxHash, zName, nName);
    if( p ) break;
  }
  return p;
}

/*
** Reclaim the memory used by an index
................................................................................
** For the index called zIdxName which is found in the database iDb,
** unlike that index from its Table then remove the index from
** the index hash table and free all memory structures associated
** with the index.
*/
void sqlite3UnlinkAndDeleteIndex(sqlite3 *db, int iDb, const char *zIdxName){
  Index *pIndex;
  int len;
  Hash *pHash;

  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  pHash = &db->aDb[iDb].pSchema->idxHash;
  len = sqlite3Strlen30(zIdxName);
  pIndex = sqlite3HashInsert(pHash, zIdxName, len, 0);
  if( ALWAYS(pIndex) ){
    if( pIndex->pTable->pIndex==pIndex ){
      pIndex->pTable->pIndex = pIndex->pNext;
    }else{
      Index *p;
      /* Justification of ALWAYS();  The index must be on the list of
      ** indices. */
................................................................................
  /* Delete all indices associated with this table. */
  for(pIndex = pTable->pIndex; pIndex; pIndex=pNext){
    pNext = pIndex->pNext;
    assert( pIndex->pSchema==pTable->pSchema );
    if( !db || db->pnBytesFreed==0 ){
      char *zName = pIndex->zName; 
      TESTONLY ( Index *pOld = ) sqlite3HashInsert(
         &pIndex->pSchema->idxHash, zName, sqlite3Strlen30(zName), 0
      );
      assert( db==0 || sqlite3SchemaMutexHeld(db, 0, pIndex->pSchema) );
      assert( pOld==pIndex || pOld==0 );
    }
    freeIndex(db, pIndex);
  }

................................................................................

  assert( db!=0 );
  assert( iDb>=0 && iDb<db->nDb );
  assert( zTabName );
  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  testcase( zTabName[0]==0 );  /* Zero-length table names are allowed */
  pDb = &db->aDb[iDb];
  p = sqlite3HashInsert(&pDb->pSchema->tblHash, zTabName,
                        sqlite3Strlen30(zTabName),0);
  sqlite3DeleteTable(db, p);
  db->flags |= SQLITE_InternChanges;
}

/*
** Given a token, return a string that consists of the text of that
** token.  Space to hold the returned string
................................................................................

  /* Add the table to the in-memory representation of the database.
  */
  if( db->init.busy ){
    Table *pOld;
    Schema *pSchema = p->pSchema;
    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    pOld = sqlite3HashInsert(&pSchema->tblHash, p->zName,
                             sqlite3Strlen30(p->zName),p);
    if( pOld ){
      assert( p==pOld );  /* Malloc must have failed inside HashInsert() */
      db->mallocFailed = 1;
      return;
    }
    pParse->pNewTable = 0;
    db->flags |= SQLITE_InternChanges;
................................................................................
  }
  pFKey->isDeferred = 0;
  pFKey->aAction[0] = (u8)(flags & 0xff);            /* ON DELETE action */
  pFKey->aAction[1] = (u8)((flags >> 8 ) & 0xff);    /* ON UPDATE action */

  assert( sqlite3SchemaMutexHeld(db, 0, p->pSchema) );
  pNextTo = (FKey *)sqlite3HashInsert(&p->pSchema->fkeyHash, 
      pFKey->zTo, sqlite3Strlen30(pFKey->zTo), (void *)pFKey
  );
  if( pNextTo==pFKey ){
    db->mallocFailed = 1;
    goto fk_end;
  }
  if( pNextTo ){
    assert( pNextTo->pPrevTo==0 );
................................................................................
  /* Link the new Index structure to its table and to the other
  ** in-memory database structures. 
  */
  if( db->init.busy ){
    Index *p;
    assert( sqlite3SchemaMutexHeld(db, 0, pIndex->pSchema) );
    p = sqlite3HashInsert(&pIndex->pSchema->idxHash, 
                          pIndex->zName, sqlite3Strlen30(pIndex->zName),
                          pIndex);
    if( p ){
      assert( p==pIndex );  /* Malloc must have failed */
      db->mallocFailed = 1;
      goto exit_create_index;
    }
    db->flags |= SQLITE_InternChanges;
    if( pTblName!=0 ){

** auxiliary databases added using the ATTACH command.
**
** See also sqlite3LocateTable().
*/
Table *sqlite3FindTable(sqlite3 *db, const char *zName, const char *zDatabase){
  Table *p = 0;
  int i;

  assert( zName!=0 );

  /* All mutexes are required for schema access.  Make sure we hold them. */
  assert( zDatabase!=0 || sqlite3BtreeHoldsAllMutexes(db) );
  for(i=OMIT_TEMPDB; i<db->nDb; i++){
    int j = (i<2) ? i^1 : i;   /* Search TEMP before MAIN */
    if( zDatabase!=0 && sqlite3StrICmp(zDatabase, db->aDb[j].zName) ) continue;
    assert( sqlite3SchemaMutexHeld(db, j, 0) );
    p = sqlite3HashFind(&db->aDb[j].pSchema->tblHash, zName);
    if( p ) break;
  }
  return p;
}

/*
** Locate the in-memory structure that describes a particular database
................................................................................
** for duplicate index names is done.)  The search order is
** TEMP first, then MAIN, then any auxiliary databases added
** using the ATTACH command.
*/
Index *sqlite3FindIndex(sqlite3 *db, const char *zName, const char *zDb){
  Index *p = 0;
  int i;

  /* All mutexes are required for schema access.  Make sure we hold them. */
  assert( zDb!=0 || sqlite3BtreeHoldsAllMutexes(db) );
  for(i=OMIT_TEMPDB; i<db->nDb; i++){
    int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
    Schema *pSchema = db->aDb[j].pSchema;
    assert( pSchema );
    if( zDb && sqlite3StrICmp(zDb, db->aDb[j].zName) ) continue;
    assert( sqlite3SchemaMutexHeld(db, j, 0) );
    p = sqlite3HashFind(&pSchema->idxHash, zName);
    if( p ) break;
  }
  return p;
}

/*
** Reclaim the memory used by an index
................................................................................
** For the index called zIdxName which is found in the database iDb,
** unlike that index from its Table then remove the index from
** the index hash table and free all memory structures associated
** with the index.
*/
void sqlite3UnlinkAndDeleteIndex(sqlite3 *db, int iDb, const char *zIdxName){
  Index *pIndex;

  Hash *pHash;

  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  pHash = &db->aDb[iDb].pSchema->idxHash;

  pIndex = sqlite3HashInsert(pHash, zIdxName, 0);
  if( ALWAYS(pIndex) ){
    if( pIndex->pTable->pIndex==pIndex ){
      pIndex->pTable->pIndex = pIndex->pNext;
    }else{
      Index *p;
      /* Justification of ALWAYS();  The index must be on the list of
      ** indices. */
................................................................................
  /* Delete all indices associated with this table. */
  for(pIndex = pTable->pIndex; pIndex; pIndex=pNext){
    pNext = pIndex->pNext;
    assert( pIndex->pSchema==pTable->pSchema );
    if( !db || db->pnBytesFreed==0 ){
      char *zName = pIndex->zName; 
      TESTONLY ( Index *pOld = ) sqlite3HashInsert(
         &pIndex->pSchema->idxHash, zName, 0
      );
      assert( db==0 || sqlite3SchemaMutexHeld(db, 0, pIndex->pSchema) );
      assert( pOld==pIndex || pOld==0 );
    }
    freeIndex(db, pIndex);
  }

................................................................................

  assert( db!=0 );
  assert( iDb>=0 && iDb<db->nDb );
  assert( zTabName );
  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  testcase( zTabName[0]==0 );  /* Zero-length table names are allowed */
  pDb = &db->aDb[iDb];
  p = sqlite3HashInsert(&pDb->pSchema->tblHash, zTabName, 0);

  sqlite3DeleteTable(db, p);
  db->flags |= SQLITE_InternChanges;
}

/*
** Given a token, return a string that consists of the text of that
** token.  Space to hold the returned string
................................................................................

  /* Add the table to the in-memory representation of the database.
  */
  if( db->init.busy ){
    Table *pOld;
    Schema *pSchema = p->pSchema;
    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    pOld = sqlite3HashInsert(&pSchema->tblHash, p->zName, p);

    if( pOld ){
      assert( p==pOld );  /* Malloc must have failed inside HashInsert() */
      db->mallocFailed = 1;
      return;
    }
    pParse->pNewTable = 0;
    db->flags |= SQLITE_InternChanges;
................................................................................
  }
  pFKey->isDeferred = 0;
  pFKey->aAction[0] = (u8)(flags & 0xff);            /* ON DELETE action */
  pFKey->aAction[1] = (u8)((flags >> 8 ) & 0xff);    /* ON UPDATE action */

  assert( sqlite3SchemaMutexHeld(db, 0, p->pSchema) );
  pNextTo = (FKey *)sqlite3HashInsert(&p->pSchema->fkeyHash, 
      pFKey->zTo, (void *)pFKey
  );
  if( pNextTo==pFKey ){
    db->mallocFailed = 1;
    goto fk_end;
  }
  if( pNextTo ){
    assert( pNextTo->pPrevTo==0 );
................................................................................
  /* Link the new Index structure to its table and to the other
  ** in-memory database structures. 
  */
  if( db->init.busy ){
    Index *p;
    assert( sqlite3SchemaMutexHeld(db, 0, pIndex->pSchema) );
    p = sqlite3HashInsert(&pIndex->pSchema->idxHash, 

                          pIndex->zName, pIndex);
    if( p ){
      assert( p==pIndex );  /* Malloc must have failed */
      db->mallocFailed = 1;
      goto exit_create_index;
    }
    db->flags |= SQLITE_InternChanges;
    if( pTblName!=0 ){

*/
static CollSeq *findCollSeqEntry(
  sqlite3 *db,          /* Database connection */
  const char *zName,    /* Name of the collating sequence */
  int create            /* Create a new entry if true */
){
  CollSeq *pColl;
  int nName = sqlite3Strlen30(zName);
  pColl = sqlite3HashFind(&db->aCollSeq, zName, nName);

  if( 0==pColl && create ){

    pColl = sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName + 1 );
    if( pColl ){
      CollSeq *pDel = 0;
      pColl[0].zName = (char*)&pColl[3];
      pColl[0].enc = SQLITE_UTF8;
      pColl[1].zName = (char*)&pColl[3];
      pColl[1].enc = SQLITE_UTF16LE;
      pColl[2].zName = (char*)&pColl[3];
      pColl[2].enc = SQLITE_UTF16BE;
      memcpy(pColl[0].zName, zName, nName);
      pColl[0].zName[nName] = 0;
      pDel = sqlite3HashInsert(&db->aCollSeq, pColl[0].zName, nName, pColl);

      /* If a malloc() failure occurred in sqlite3HashInsert(), it will 
      ** return the pColl pointer to be deleted (because it wasn't added
      ** to the hash table).
      */
      assert( pDel==0 || pDel==pColl );
      if( pDel!=0 ){

*/
static CollSeq *findCollSeqEntry(
  sqlite3 *db,          /* Database connection */
  const char *zName,    /* Name of the collating sequence */
  int create            /* Create a new entry if true */
){
  CollSeq *pColl;

  pColl = sqlite3HashFind(&db->aCollSeq, zName);

  if( 0==pColl && create ){
    int nName = sqlite3Strlen30(zName);
    pColl = sqlite3DbMallocZero(db, 3*sizeof(*pColl) + nName + 1);
    if( pColl ){
      CollSeq *pDel = 0;
      pColl[0].zName = (char*)&pColl[3];
      pColl[0].enc = SQLITE_UTF8;
      pColl[1].zName = (char*)&pColl[3];
      pColl[1].enc = SQLITE_UTF16LE;
      pColl[2].zName = (char*)&pColl[3];
      pColl[2].enc = SQLITE_UTF16BE;
      memcpy(pColl[0].zName, zName, nName);
      pColl[0].zName[nName] = 0;
      pDel = sqlite3HashInsert(&db->aCollSeq, pColl[0].zName, pColl);

      /* If a malloc() failure occurred in sqlite3HashInsert(), it will 
      ** return the pColl pointer to be deleted (because it wasn't added
      ** to the hash table).
      */
      assert( pDel==0 || pDel==pColl );
      if( pDel!=0 ){

    case TK_AS: {
      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
      break;
    }
#ifndef SQLITE_OMIT_CAST
    case TK_CAST: {
      /* Expressions of the form:   CAST(pLeft AS token) */
      int aff, to_op;
      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
      assert( !ExprHasProperty(pExpr, EP_IntValue) );
      aff = sqlite3AffinityType(pExpr->u.zToken, 0);
      to_op = aff - SQLITE_AFF_TEXT + OP_ToText;
      assert( to_op==OP_ToText    || aff!=SQLITE_AFF_TEXT    );
      assert( to_op==OP_ToBlob    || aff!=SQLITE_AFF_NONE    );
      assert( to_op==OP_ToNumeric || aff!=SQLITE_AFF_NUMERIC );
      assert( to_op==OP_ToInt     || aff!=SQLITE_AFF_INTEGER );
      assert( to_op==OP_ToReal    || aff!=SQLITE_AFF_REAL    );
      testcase( to_op==OP_ToText );
      testcase( to_op==OP_ToBlob );
      testcase( to_op==OP_ToNumeric );
      testcase( to_op==OP_ToInt );
      testcase( to_op==OP_ToReal );
      if( inReg!=target ){
        sqlite3VdbeAddOp2(v, OP_SCopy, inReg, target);
        inReg = target;
      }
      sqlite3VdbeAddOp1(v, to_op, inReg);

      testcase( usedAsColumnCache(pParse, inReg, inReg) );
      sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
      break;
    }
#endif /* SQLITE_OMIT_CAST */
    case TK_LT:
    case TK_LE:

    case TK_AS: {
      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);
      break;
    }
#ifndef SQLITE_OMIT_CAST
    case TK_CAST: {
      /* Expressions of the form:   CAST(pLeft AS token) */

      inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target);













      if( inReg!=target ){
        sqlite3VdbeAddOp2(v, OP_SCopy, inReg, target);
        inReg = target;
      }
      sqlite3VdbeAddOp2(v, OP_Cast, target,
                        sqlite3AffinityType(pExpr->u.zToken, 0));
      testcase( usedAsColumnCache(pParse, inReg, inReg) );
      sqlite3ExprCacheAffinityChange(pParse, inReg, 1);
      break;
    }
#endif /* SQLITE_OMIT_CAST */
    case TK_LT:
    case TK_LE:

** Calling this function with table "t1" as an argument returns a pointer
** to the FKey structure representing the foreign key constraint on table
** "t2". Calling this function with "t2" as the argument would return a
** NULL pointer (as there are no FK constraints for which t2 is the parent
** table).
*/
FKey *sqlite3FkReferences(Table *pTab){
  int nName = sqlite3Strlen30(pTab->zName);
  return (FKey *)sqlite3HashFind(&pTab->pSchema->fkeyHash, pTab->zName, nName);
}

/*
** The second argument is a Trigger structure allocated by the 
** fkActionTrigger() routine. This function deletes the Trigger structure
** and all of its sub-components.
**
................................................................................
    /* Remove the FK from the fkeyHash hash table. */
    if( !db || db->pnBytesFreed==0 ){
      if( pFKey->pPrevTo ){
        pFKey->pPrevTo->pNextTo = pFKey->pNextTo;
      }else{
        void *p = (void *)pFKey->pNextTo;
        const char *z = (p ? pFKey->pNextTo->zTo : pFKey->zTo);
        sqlite3HashInsert(&pTab->pSchema->fkeyHash, z, sqlite3Strlen30(z), p);
      }
      if( pFKey->pNextTo ){
        pFKey->pNextTo->pPrevTo = pFKey->pPrevTo;
      }
    }

    /* EV: R-30323-21917 Each foreign key constraint in SQLite is

** Calling this function with table "t1" as an argument returns a pointer
** to the FKey structure representing the foreign key constraint on table
** "t2". Calling this function with "t2" as the argument would return a
** NULL pointer (as there are no FK constraints for which t2 is the parent
** table).
*/
FKey *sqlite3FkReferences(Table *pTab){

  return (FKey *)sqlite3HashFind(&pTab->pSchema->fkeyHash, pTab->zName);
}

/*
** The second argument is a Trigger structure allocated by the 
** fkActionTrigger() routine. This function deletes the Trigger structure
** and all of its sub-components.
**
................................................................................
    /* Remove the FK from the fkeyHash hash table. */
    if( !db || db->pnBytesFreed==0 ){
      if( pFKey->pPrevTo ){
        pFKey->pPrevTo->pNextTo = pFKey->pNextTo;
      }else{
        void *p = (void *)pFKey->pNextTo;
        const char *z = (p ? pFKey->pNextTo->zTo : pFKey->zTo);
        sqlite3HashInsert(&pTab->pSchema->fkeyHash, z, p);
      }
      if( pFKey->pNextTo ){
        pFKey->pNextTo->pPrevTo = pFKey->pPrevTo;
      }
    }

    /* EV: R-30323-21917 Each foreign key constraint in SQLite is

  }
  pH->count = 0;
}

/*
** The hashing function.
*/
static unsigned int strHash(const char *z, int nKey){
  unsigned int h = 0;
  assert( nKey>=0 );
  while( nKey > 0  ){
    h = (h<<3) ^ h ^ sqlite3UpperToLower[(unsigned char)*z++];
    nKey--;
  }
  return h;
}


/* Link pNew element into the hash table pH.  If pEntry!=0 then also
** insert pNew into the pEntry hash bucket.
................................................................................

  if( new_ht==0 ) return 0;
  sqlite3_free(pH->ht);
  pH->ht = new_ht;
  pH->htsize = new_size = sqlite3MallocSize(new_ht)/sizeof(struct _ht);
  memset(new_ht, 0, new_size*sizeof(struct _ht));
  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
    unsigned int h = strHash(elem->pKey, elem->nKey) % new_size;
    next_elem = elem->next;
    insertElement(pH, &new_ht[h], elem);
  }
  return 1;
}

/* This function (for internal use only) locates an element in an
** hash table that matches the given key.  The hash for this key has
** already been computed and is passed as the 4th parameter.
*/
static HashElem *findElementGivenHash(
  const Hash *pH,     /* The pH to be searched */
  const char *pKey,   /* The key we are searching for */
  int nKey,           /* Bytes in key (not counting zero terminator) */
  unsigned int h      /* The hash for this key. */
){
  HashElem *elem;                /* Used to loop thru the element list */
  int count;                     /* Number of elements left to test */


  if( pH->ht ){


    struct _ht *pEntry = &pH->ht[h];
    elem = pEntry->chain;
    count = pEntry->count;
  }else{

    elem = pH->first;
    count = pH->count;
  }

  while( count-- && ALWAYS(elem) ){

    if( elem->nKey==nKey && sqlite3StrNICmp(elem->pKey,pKey,nKey)==0 ){ 
      return elem;
    }
    elem = elem->next;
  }
  return 0;
}

................................................................................
    assert( pH->first==0 );
    assert( pH->count==0 );
    sqlite3HashClear(pH);
  }
}

/* Attempt to locate an element of the hash table pH with a key
** that matches pKey,nKey.  Return the data for this element if it is
** found, or NULL if there is no match.
*/
void *sqlite3HashFind(const Hash *pH, const char *pKey, int nKey){
  HashElem *elem;    /* The element that matches key */
  unsigned int h;    /* A hash on key */

  assert( pH!=0 );
  assert( pKey!=0 );
  assert( nKey>=0 );
  if( pH->ht ){
    h = strHash(pKey, nKey) % pH->htsize;
  }else{
    h = 0;
  }
  elem = findElementGivenHash(pH, pKey, nKey, h);
  return elem ? elem->data : 0;
}

/* Insert an element into the hash table pH.  The key is pKey,nKey
** and the data is "data".
**
** If no element exists with a matching key, then a new
** element is created and NULL is returned.
**
** If another element already exists with the same key, then the
** new data replaces the old data and the old data is returned.
** The key is not copied in this instance.  If a malloc fails, then
** the new data is returned and the hash table is unchanged.
**
** If the "data" parameter to this function is NULL, then the
** element corresponding to "key" is removed from the hash table.
*/
void *sqlite3HashInsert(Hash *pH, const char *pKey, int nKey, void *data){
  unsigned int h;       /* the hash of the key modulo hash table size */
  HashElem *elem;       /* Used to loop thru the element list */
  HashElem *new_elem;   /* New element added to the pH */

  assert( pH!=0 );
  assert( pKey!=0 );
  assert( nKey>=0 );
  if( pH->htsize ){
    h = strHash(pKey, nKey) % pH->htsize;
  }else{
    h = 0;
  }
  elem = findElementGivenHash(pH,pKey,nKey,h);
  if( elem ){
    void *old_data = elem->data;
    if( data==0 ){
      removeElementGivenHash(pH,elem,h);
    }else{
      elem->data = data;
      elem->pKey = pKey;
      assert(nKey==elem->nKey);
    }
    return old_data;
  }
  if( data==0 ) return 0;
  new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) );
  if( new_elem==0 ) return data;
  new_elem->pKey = pKey;
  new_elem->nKey = nKey;
  new_elem->data = data;
  pH->count++;
  if( pH->count>=10 && pH->count > 2*pH->htsize ){
    if( rehash(pH, pH->count*2) ){
      assert( pH->htsize>0 );
      h = strHash(pKey, nKey) % pH->htsize;
    }
  }
  if( pH->ht ){
    insertElement(pH, &pH->ht[h], new_elem);
  }else{
    insertElement(pH, 0, new_elem);
  }
  return 0;
}

  }
  pH->count = 0;
}

/*
** The hashing function.
*/
static unsigned int strHash(const char *z){
  unsigned int h = 0;
  unsigned char c;
  while( (c = (unsigned char)*z++)!=0 ){
    h = (h<<3) ^ h ^ sqlite3UpperToLower[c];

  }
  return h;
}


/* Link pNew element into the hash table pH.  If pEntry!=0 then also
** insert pNew into the pEntry hash bucket.
................................................................................

  if( new_ht==0 ) return 0;
  sqlite3_free(pH->ht);
  pH->ht = new_ht;
  pH->htsize = new_size = sqlite3MallocSize(new_ht)/sizeof(struct _ht);
  memset(new_ht, 0, new_size*sizeof(struct _ht));
  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
    unsigned int h = strHash(elem->pKey) % new_size;
    next_elem = elem->next;
    insertElement(pH, &new_ht[h], elem);
  }
  return 1;
}

/* This function (for internal use only) locates an element in an
** hash table that matches the given key.  The hash for this key is
** also computed and returned in the *pH parameter.
*/
static HashElem *findElementWithHash(
  const Hash *pH,     /* The pH to be searched */
  const char *pKey,   /* The key we are searching for */
  unsigned int *pHash /* Write the hash value here */

){
  HashElem *elem;                /* Used to loop thru the element list */
  int count;                     /* Number of elements left to test */
  unsigned int h;                /* The computed hash */

  if( pH->ht ){
    struct _ht *pEntry;
    h = strHash(pKey) % pH->htsize;
    pEntry = &pH->ht[h];
    elem = pEntry->chain;
    count = pEntry->count;
  }else{
    h = 0;
    elem = pH->first;
    count = pH->count;
  }
  *pHash = h;
  while( count-- ){
    assert( elem!=0 );
    if( sqlite3StrICmp(elem->pKey,pKey)==0 ){ 
      return elem;
    }
    elem = elem->next;
  }
  return 0;
}

................................................................................
    assert( pH->first==0 );
    assert( pH->count==0 );
    sqlite3HashClear(pH);
  }
}

/* Attempt to locate an element of the hash table pH with a key
** that matches pKey.  Return the data for this element if it is
** found, or NULL if there is no match.
*/
void *sqlite3HashFind(const Hash *pH, const char *pKey){
  HashElem *elem;    /* The element that matches key */
  unsigned int h;    /* A hash on key */

  assert( pH!=0 );
  assert( pKey!=0 );






  elem = findElementWithHash(pH, pKey, &h);
  return elem ? elem->data : 0;
}

/* Insert an element into the hash table pH.  The key is pKey
** and the data is "data".
**
** If no element exists with a matching key, then a new
** element is created and NULL is returned.
**
** If another element already exists with the same key, then the
** new data replaces the old data and the old data is returned.
** The key is not copied in this instance.  If a malloc fails, then
** the new data is returned and the hash table is unchanged.
**
** If the "data" parameter to this function is NULL, then the
** element corresponding to "key" is removed from the hash table.
*/
void *sqlite3HashInsert(Hash *pH, const char *pKey, void *data){
  unsigned int h;       /* the hash of the key modulo hash table size */
  HashElem *elem;       /* Used to loop thru the element list */
  HashElem *new_elem;   /* New element added to the pH */

  assert( pH!=0 );
  assert( pKey!=0 );






  elem = findElementWithHash(pH,pKey,&h);
  if( elem ){
    void *old_data = elem->data;
    if( data==0 ){
      removeElementGivenHash(pH,elem,h);
    }else{
      elem->data = data;
      elem->pKey = pKey;

    }
    return old_data;
  }
  if( data==0 ) return 0;
  new_elem = (HashElem*)sqlite3Malloc( sizeof(HashElem) );
  if( new_elem==0 ) return data;
  new_elem->pKey = pKey;

  new_elem->data = data;
  pH->count++;
  if( pH->count>=10 && pH->count > 2*pH->htsize ){
    if( rehash(pH, pH->count*2) ){
      assert( pH->htsize>0 );
      h = strHash(pKey) % pH->htsize;
    }
  }



  insertElement(pH, pH->ht ? &pH->ht[h] : 0, new_elem);

  return 0;
}

**
** Again, this structure is intended to be opaque, but it can't really
** be opaque because it is used by macros.
*/
struct HashElem {
  HashElem *next, *prev;       /* Next and previous elements in the table */
  void *data;                  /* Data associated with this element */
  const char *pKey; int nKey;  /* Key associated with this element */
};

/*
** Access routines.  To delete, insert a NULL pointer.
*/
void sqlite3HashInit(Hash*);
void *sqlite3HashInsert(Hash*, const char *pKey, int nKey, void *pData);
void *sqlite3HashFind(const Hash*, const char *pKey, int nKey);
void sqlite3HashClear(Hash*);

/*
** Macros for looping over all elements of a hash table.  The idiom is
** like this:
**
**   Hash h;

**
** Again, this structure is intended to be opaque, but it can't really
** be opaque because it is used by macros.
*/
struct HashElem {
  HashElem *next, *prev;       /* Next and previous elements in the table */
  void *data;                  /* Data associated with this element */
  const char *pKey;            /* Key associated with this element */
};

/*
** Access routines.  To delete, insert a NULL pointer.
*/
void sqlite3HashInit(Hash*);
void *sqlite3HashInsert(Hash*, const char *pKey, void *pData);
void *sqlite3HashFind(const Hash*, const char *pKey);
void sqlite3HashClear(Hash*);

/*
** Macros for looping over all elements of a hash table.  The idiom is
** like this:
**
**   Hash h;

  char **azCols = 0;          /* Names of result columns */
  int callbackIsInit;         /* True if callback data is initialized */

  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
  if( zSql==0 ) zSql = "";

  sqlite3_mutex_enter(db->mutex);
  sqlite3Error(db, SQLITE_OK, 0);
  while( rc==SQLITE_OK && zSql[0] ){
    int nCol;
    char **azVals = 0;

    pStmt = 0;
    rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, &zLeftover);
    assert( rc==SQLITE_OK || pStmt==0 );
................................................................................
        if( xCallback(pArg, nCol, azVals, azCols) ){
          /* EVIDENCE-OF: R-38229-40159 If the callback function to
          ** sqlite3_exec() returns non-zero, then sqlite3_exec() will
          ** return SQLITE_ABORT. */
          rc = SQLITE_ABORT;
          sqlite3VdbeFinalize((Vdbe *)pStmt);
          pStmt = 0;
          sqlite3Error(db, SQLITE_ABORT, 0);
          goto exec_out;
        }
      }

      if( rc!=SQLITE_ROW ){
        rc = sqlite3VdbeFinalize((Vdbe *)pStmt);
        pStmt = 0;
................................................................................
  if( rc!=SQLITE_OK && ALWAYS(rc==sqlite3_errcode(db)) && pzErrMsg ){
    int nErrMsg = 1 + sqlite3Strlen30(sqlite3_errmsg(db));
    *pzErrMsg = sqlite3Malloc(nErrMsg);
    if( *pzErrMsg ){
      memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);
    }else{
      rc = SQLITE_NOMEM;
      sqlite3Error(db, SQLITE_NOMEM, 0);
    }
  }else if( pzErrMsg ){
    *pzErrMsg = 0;
  }

  assert( (rc&db->errMask)==rc );
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

  char **azCols = 0;          /* Names of result columns */
  int callbackIsInit;         /* True if callback data is initialized */

  if( !sqlite3SafetyCheckOk(db) ) return SQLITE_MISUSE_BKPT;
  if( zSql==0 ) zSql = "";

  sqlite3_mutex_enter(db->mutex);
  sqlite3Error(db, SQLITE_OK);
  while( rc==SQLITE_OK && zSql[0] ){
    int nCol;
    char **azVals = 0;

    pStmt = 0;
    rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, &zLeftover);
    assert( rc==SQLITE_OK || pStmt==0 );
................................................................................
        if( xCallback(pArg, nCol, azVals, azCols) ){
          /* EVIDENCE-OF: R-38229-40159 If the callback function to
          ** sqlite3_exec() returns non-zero, then sqlite3_exec() will
          ** return SQLITE_ABORT. */
          rc = SQLITE_ABORT;
          sqlite3VdbeFinalize((Vdbe *)pStmt);
          pStmt = 0;
          sqlite3Error(db, SQLITE_ABORT);
          goto exec_out;
        }
      }

      if( rc!=SQLITE_ROW ){
        rc = sqlite3VdbeFinalize((Vdbe *)pStmt);
        pStmt = 0;
................................................................................
  if( rc!=SQLITE_OK && ALWAYS(rc==sqlite3_errcode(db)) && pzErrMsg ){
    int nErrMsg = 1 + sqlite3Strlen30(sqlite3_errmsg(db));
    *pzErrMsg = sqlite3Malloc(nErrMsg);
    if( *pzErrMsg ){
      memcpy(*pzErrMsg, sqlite3_errmsg(db), nErrMsg);
    }else{
      rc = SQLITE_NOMEM;
      sqlite3Error(db, SQLITE_NOMEM);
    }
  }else if( pzErrMsg ){
    *pzErrMsg = 0;
  }

  assert( (rc&db->errMask)==rc );
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

    }else{
      xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
              wsdAutoext.aExt[i];
    }
    sqlite3_mutex_leave(mutex);
    zErrmsg = 0;
    if( xInit && (rc = xInit(db, &zErrmsg, &sqlite3Apis))!=0 ){
      sqlite3Error(db, rc,
            "automatic extension loading failed: %s", zErrmsg);
      go = 0;
    }
    sqlite3_free(zErrmsg);
  }
}

    }else{
      xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))
              wsdAutoext.aExt[i];
    }
    sqlite3_mutex_leave(mutex);
    zErrmsg = 0;
    if( xInit && (rc = xInit(db, &zErrmsg, &sqlite3Apis))!=0 ){
      sqlite3ErrorWithMsg(db, rc,
            "automatic extension loading failed: %s", zErrmsg);
      go = 0;
    }
    sqlite3_free(zErrmsg);
  }
}

  */
  sqlite3VtabRollback(db);

  /* Legacy behavior (sqlite3_close() behavior) is to return
  ** SQLITE_BUSY if the connection can not be closed immediately.
  */
  if( !forceZombie && connectionIsBusy(db) ){
    sqlite3Error(db, SQLITE_BUSY, "unable to close due to unfinalized "
       "statements or unfinished backups");
    sqlite3_mutex_leave(db->mutex);
    return SQLITE_BUSY;
  }

#ifdef SQLITE_ENABLE_SQLLOG
  if( sqlite3GlobalConfig.xSqllog ){
................................................................................
      pMod->xDestroy(pMod->pAux);
    }
    sqlite3DbFree(db, pMod);
  }
  sqlite3HashClear(&db->aModule);
#endif

  sqlite3Error(db, SQLITE_OK, 0); /* Deallocates any cached error strings. */
  sqlite3ValueFree(db->pErr);
  sqlite3CloseExtensions(db);

  db->magic = SQLITE_MAGIC_ERROR;

  /* The temp-database schema is allocated differently from the other schema
  ** objects (using sqliteMalloc() directly, instead of sqlite3BtreeSchema()).
................................................................................
  ** 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 ){
      sqlite3Error(db, SQLITE_BUSY, 
        "unable to delete/modify user-function due to active statements");
      assert( !db->mallocFailed );
      return SQLITE_BUSY;
    }else{
      sqlite3ExpirePreparedStatements(db);
    }
  }
................................................................................

  sqlite3_mutex_enter(db->mutex);
  if( zDb && zDb[0] ){
    iDb = sqlite3FindDbName(db, zDb);
  }
  if( iDb<0 ){
    rc = SQLITE_ERROR;
    sqlite3Error(db, SQLITE_ERROR, "unknown database: %s", zDb);
  }else{
    rc = sqlite3Checkpoint(db, iDb, eMode, pnLog, pnCkpt);
    sqlite3Error(db, rc, 0);
  }
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
#endif
}

................................................................................
  }
  sqlite3_mutex_enter(db->mutex);
  if( db->mallocFailed ){
    z = (void *)outOfMem;
  }else{
    z = sqlite3_value_text16(db->pErr);
    if( z==0 ){
      sqlite3Error(db, db->errCode, sqlite3ErrStr(db->errCode));
      z = sqlite3_value_text16(db->pErr);
    }
    /* A malloc() may have failed within the call to sqlite3_value_text16()
    ** above. If this is the case, then the db->mallocFailed flag needs to
    ** be cleared before returning. Do this directly, instead of via
    ** sqlite3ApiExit(), to avoid setting the database handle error message.
    */
................................................................................
  u8 enc,
  void* pCtx,
  int(*xCompare)(void*,int,const void*,int,const void*),
  void(*xDel)(void*)
){
  CollSeq *pColl;
  int enc2;
  int nName = sqlite3Strlen30(zName);
  
  assert( sqlite3_mutex_held(db->mutex) );

  /* If SQLITE_UTF16 is specified as the encoding type, transform this
  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
  */
................................................................................
  /* Check if this call is removing or replacing an existing collation 
  ** sequence. If so, and there are active VMs, return busy. If there
  ** are no active VMs, invalidate any pre-compiled statements.
  */
  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, 0);
  if( pColl && pColl->xCmp ){
    if( db->nVdbeActive ){
      sqlite3Error(db, SQLITE_BUSY, 
        "unable to delete/modify collation sequence due to active statements");
      return SQLITE_BUSY;
    }
    sqlite3ExpirePreparedStatements(db);
    invalidateCachedKeyInfo(db);

    /* If collation sequence pColl was created directly by a call to
    ** sqlite3_create_collation, and not generated by synthCollSeq(),
    ** then any copies made by synthCollSeq() need to be invalidated.
    ** Also, collation destructor - CollSeq.xDel() - function may need
    ** to be called.
    */ 
    if( (pColl->enc & ~SQLITE_UTF16_ALIGNED)==enc2 ){
      CollSeq *aColl = sqlite3HashFind(&db->aCollSeq, zName, nName);
      int j;
      for(j=0; j<3; j++){
        CollSeq *p = &aColl[j];
        if( p->enc==pColl->enc ){
          if( p->xDel ){
            p->xDel(p->pUser);
          }
................................................................................

  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, 1);
  if( pColl==0 ) return SQLITE_NOMEM;
  pColl->xCmp = xCompare;
  pColl->pUser = pCtx;
  pColl->xDel = xDel;
  pColl->enc = (u8)(enc2 | (enc & SQLITE_UTF16_ALIGNED));
  sqlite3Error(db, SQLITE_OK, 0);
  return SQLITE_OK;
}


/*
** This array defines hard upper bounds on limit values.  The
** initializer must be kept in sync with the SQLITE_LIMIT_*
................................................................................
  createCollation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc, 0);

  /* Parse the filename/URI argument. */
  db->openFlags = flags;
  rc = sqlite3ParseUri(zVfs, zFilename, &flags, &db->pVfs, &zOpen, &zErrMsg);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_NOMEM ) db->mallocFailed = 1;
    sqlite3Error(db, rc, zErrMsg ? "%s" : 0, zErrMsg);
    sqlite3_free(zErrMsg);
    goto opendb_out;
  }

  /* Open the backend database driver */
  rc = sqlite3BtreeOpen(db->pVfs, zOpen, db, &db->aDb[0].pBt, 0,
                        flags | SQLITE_OPEN_MAIN_DB);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_IOERR_NOMEM ){
      rc = SQLITE_NOMEM;
    }
    sqlite3Error(db, rc, 0);
    goto opendb_out;
  }
  db->aDb[0].pSchema = sqlite3SchemaGet(db, db->aDb[0].pBt);
  db->aDb[1].pSchema = sqlite3SchemaGet(db, 0);


  /* The default safety_level for the main database is 'full'; for the temp
................................................................................
    goto opendb_out;
  }

  /* 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, 0);
  sqlite3RegisterBuiltinFunctions(db);

  /* Load automatic extensions - extensions that have been registered
  ** using the sqlite3_automatic_extension() API.
  */
  rc = sqlite3_errcode(db);
  if( rc==SQLITE_OK ){
................................................................................
  */
#ifdef SQLITE_DEFAULT_LOCKING_MODE
  db->dfltLockMode = SQLITE_DEFAULT_LOCKING_MODE;
  sqlite3PagerLockingMode(sqlite3BtreePager(db->aDb[0].pBt),
                          SQLITE_DEFAULT_LOCKING_MODE);
#endif

  if( rc ) sqlite3Error(db, rc, 0);

  /* Enable the lookaside-malloc subsystem */
  setupLookaside(db, 0, sqlite3GlobalConfig.szLookaside,
                        sqlite3GlobalConfig.nLookaside);

  sqlite3_wal_autocheckpoint(db, SQLITE_DEFAULT_WAL_AUTOCHECKPOINT);

................................................................................

  if( SQLITE_OK==rc && !pTab ){
    sqlite3DbFree(db, zErrMsg);
    zErrMsg = sqlite3MPrintf(db, "no such table column: %s.%s", zTableName,
        zColumnName);
    rc = SQLITE_ERROR;
  }
  sqlite3Error(db, rc, (zErrMsg?"%s":0), zErrMsg);
  sqlite3DbFree(db, zErrMsg);
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}
#endif

  */
  sqlite3VtabRollback(db);

  /* Legacy behavior (sqlite3_close() behavior) is to return
  ** SQLITE_BUSY if the connection can not be closed immediately.
  */
  if( !forceZombie && connectionIsBusy(db) ){
    sqlite3ErrorWithMsg(db, SQLITE_BUSY, "unable to close due to unfinalized "
       "statements or unfinished backups");
    sqlite3_mutex_leave(db->mutex);
    return SQLITE_BUSY;
  }

#ifdef SQLITE_ENABLE_SQLLOG
  if( sqlite3GlobalConfig.xSqllog ){
................................................................................
      pMod->xDestroy(pMod->pAux);
    }
    sqlite3DbFree(db, pMod);
  }
  sqlite3HashClear(&db->aModule);
#endif

  sqlite3Error(db, SQLITE_OK); /* Deallocates any cached error strings. */
  sqlite3ValueFree(db->pErr);
  sqlite3CloseExtensions(db);

  db->magic = SQLITE_MAGIC_ERROR;

  /* The temp-database schema is allocated differently from the other schema
  ** objects (using sqliteMalloc() directly, instead of sqlite3BtreeSchema()).
................................................................................
  ** 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);
    }
  }
................................................................................

  sqlite3_mutex_enter(db->mutex);
  if( zDb && zDb[0] ){
    iDb = sqlite3FindDbName(db, zDb);
  }
  if( iDb<0 ){
    rc = SQLITE_ERROR;
    sqlite3ErrorWithMsg(db, SQLITE_ERROR, "unknown database: %s", zDb);
  }else{
    rc = sqlite3Checkpoint(db, iDb, eMode, pnLog, pnCkpt);
    sqlite3Error(db, rc);
  }
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
#endif
}

................................................................................
  }
  sqlite3_mutex_enter(db->mutex);
  if( db->mallocFailed ){
    z = (void *)outOfMem;
  }else{
    z = sqlite3_value_text16(db->pErr);
    if( z==0 ){
      sqlite3ErrorWithMsg(db, db->errCode, sqlite3ErrStr(db->errCode));
      z = sqlite3_value_text16(db->pErr);
    }
    /* A malloc() may have failed within the call to sqlite3_value_text16()
    ** above. If this is the case, then the db->mallocFailed flag needs to
    ** be cleared before returning. Do this directly, instead of via
    ** sqlite3ApiExit(), to avoid setting the database handle error message.
    */
................................................................................
  u8 enc,
  void* pCtx,
  int(*xCompare)(void*,int,const void*,int,const void*),
  void(*xDel)(void*)
){
  CollSeq *pColl;
  int enc2;

  
  assert( sqlite3_mutex_held(db->mutex) );

  /* If SQLITE_UTF16 is specified as the encoding type, transform this
  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
  */
................................................................................
  /* Check if this call is removing or replacing an existing collation 
  ** sequence. If so, and there are active VMs, return busy. If there
  ** are no active VMs, invalidate any pre-compiled statements.
  */
  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, 0);
  if( pColl && pColl->xCmp ){
    if( db->nVdbeActive ){
      sqlite3ErrorWithMsg(db, SQLITE_BUSY, 
        "unable to delete/modify collation sequence due to active statements");
      return SQLITE_BUSY;
    }
    sqlite3ExpirePreparedStatements(db);
    invalidateCachedKeyInfo(db);

    /* If collation sequence pColl was created directly by a call to
    ** sqlite3_create_collation, and not generated by synthCollSeq(),
    ** then any copies made by synthCollSeq() need to be invalidated.
    ** Also, collation destructor - CollSeq.xDel() - function may need
    ** to be called.
    */ 
    if( (pColl->enc & ~SQLITE_UTF16_ALIGNED)==enc2 ){
      CollSeq *aColl = sqlite3HashFind(&db->aCollSeq, zName);
      int j;
      for(j=0; j<3; j++){
        CollSeq *p = &aColl[j];
        if( p->enc==pColl->enc ){
          if( p->xDel ){
            p->xDel(p->pUser);
          }
................................................................................

  pColl = sqlite3FindCollSeq(db, (u8)enc2, zName, 1);
  if( pColl==0 ) return SQLITE_NOMEM;
  pColl->xCmp = xCompare;
  pColl->pUser = pCtx;
  pColl->xDel = xDel;
  pColl->enc = (u8)(enc2 | (enc & SQLITE_UTF16_ALIGNED));
  sqlite3Error(db, SQLITE_OK);
  return SQLITE_OK;
}


/*
** This array defines hard upper bounds on limit values.  The
** initializer must be kept in sync with the SQLITE_LIMIT_*
................................................................................
  createCollation(db, "NOCASE", SQLITE_UTF8, 0, nocaseCollatingFunc, 0);

  /* Parse the filename/URI argument. */
  db->openFlags = flags;
  rc = sqlite3ParseUri(zVfs, zFilename, &flags, &db->pVfs, &zOpen, &zErrMsg);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_NOMEM ) db->mallocFailed = 1;
    sqlite3ErrorWithMsg(db, rc, zErrMsg ? "%s" : 0, zErrMsg);
    sqlite3_free(zErrMsg);
    goto opendb_out;
  }

  /* Open the backend database driver */
  rc = sqlite3BtreeOpen(db->pVfs, zOpen, db, &db->aDb[0].pBt, 0,
                        flags | SQLITE_OPEN_MAIN_DB);
  if( rc!=SQLITE_OK ){
    if( rc==SQLITE_IOERR_NOMEM ){
      rc = SQLITE_NOMEM;
    }
    sqlite3Error(db, rc);
    goto opendb_out;
  }
  db->aDb[0].pSchema = sqlite3SchemaGet(db, db->aDb[0].pBt);
  db->aDb[1].pSchema = sqlite3SchemaGet(db, 0);


  /* The default safety_level for the main database is 'full'; for the temp
................................................................................
    goto opendb_out;
  }

  /* 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 ){
................................................................................
  */
#ifdef SQLITE_DEFAULT_LOCKING_MODE
  db->dfltLockMode = SQLITE_DEFAULT_LOCKING_MODE;
  sqlite3PagerLockingMode(sqlite3BtreePager(db->aDb[0].pBt),
                          SQLITE_DEFAULT_LOCKING_MODE);
#endif

  if( rc ) sqlite3Error(db, rc);

  /* Enable the lookaside-malloc subsystem */
  setupLookaside(db, 0, sqlite3GlobalConfig.szLookaside,
                        sqlite3GlobalConfig.nLookaside);

  sqlite3_wal_autocheckpoint(db, SQLITE_DEFAULT_WAL_AUTOCHECKPOINT);

................................................................................

  if( SQLITE_OK==rc && !pTab ){
    sqlite3DbFree(db, zErrMsg);
    zErrMsg = sqlite3MPrintf(db, "no such table column: %s.%s", zTableName,
        zColumnName);
    rc = SQLITE_ERROR;
  }
  sqlite3ErrorWithMsg(db, rc, (zErrMsg?"%s":0), zErrMsg);
  sqlite3DbFree(db, zErrMsg);
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}
#endif

** embedded processor.
*/
void *sqlite3ScratchMalloc(int n){
  void *p;
  assert( n>0 );

  sqlite3_mutex_enter(mem0.mutex);

  if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
    p = mem0.pScratchFree;
    mem0.pScratchFree = mem0.pScratchFree->pNext;
    mem0.nScratchFree--;
    sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);
    sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
    sqlite3_mutex_leave(mem0.mutex);
  }else{


    if( sqlite3GlobalConfig.bMemstat ){
      sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
      n = mallocWithAlarm(n, &p);
      if( p ) sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, n);
      sqlite3_mutex_leave(mem0.mutex);
    }else{
      sqlite3_mutex_leave(mem0.mutex);
      p = sqlite3GlobalConfig.m.xMalloc(n);
    }
    sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
  }
  assert( sqlite3_mutex_notheld(mem0.mutex) );


#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
................................................................................
    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
    sqlite3GlobalConfig.m.xFree(p);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    sqlite3GlobalConfig.m.xFree(p);
  }
}









/*
** Free memory that might be associated with a particular database
** connection.
*/
void sqlite3DbFree(sqlite3 *db, void *p){
  assert( db==0 || sqlite3_mutex_held(db->mutex) );
  if( p==0 ) return;
  if( db ){
    if( db->pnBytesFreed ){
      *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
      return;
    }
    if( isLookaside(db, p) ){
      LookasideSlot *pBuf = (LookasideSlot*)p;
#if SQLITE_DEBUG
      /* Trash all content in the buffer being freed */
      memset(p, 0xaa, db->lookaside.sz);
................................................................................
  va_start(ap, zFormat);
  z = sqlite3VMPrintf(db, zFormat, ap);
  va_end(ap);
  sqlite3DbFree(db, *pz);
  *pz = z;
}










/*
** This function must be called before exiting any API function (i.e. 
** returning control to the user) that has called sqlite3_malloc or
** sqlite3_realloc.
**
** The returned value is normally a copy of the second argument to this
................................................................................
*/
int sqlite3ApiExit(sqlite3* db, int rc){
  /* If the db handle is not NULL, then we must hold the connection handle
  ** mutex here. Otherwise the read (and possible write) of db->mallocFailed 
  ** is unsafe, as is the call to sqlite3Error().
  */
  assert( !db || sqlite3_mutex_held(db->mutex) );

  if( db && (db->mallocFailed || rc==SQLITE_IOERR_NOMEM) ){
    sqlite3Error(db, SQLITE_NOMEM, 0);
    db->mallocFailed = 0;
    rc = SQLITE_NOMEM;
  }
  return rc & (db ? db->errMask : 0xff);
}

** embedded processor.
*/
void *sqlite3ScratchMalloc(int n){
  void *p;
  assert( n>0 );

  sqlite3_mutex_enter(mem0.mutex);
  sqlite3StatusSet(SQLITE_STATUS_SCRATCH_SIZE, n);
  if( mem0.nScratchFree && sqlite3GlobalConfig.szScratch>=n ){
    p = mem0.pScratchFree;
    mem0.pScratchFree = mem0.pScratchFree->pNext;
    mem0.nScratchFree--;
    sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_USED, 1);

    sqlite3_mutex_leave(mem0.mutex);
  }else{
    sqlite3_mutex_leave(mem0.mutex);
    p = sqlite3Malloc(n);
    if( sqlite3GlobalConfig.bMemstat && p ){

      sqlite3_mutex_enter(mem0.mutex);
      sqlite3StatusAdd(SQLITE_STATUS_SCRATCH_OVERFLOW, sqlite3MallocSize(p));
      sqlite3_mutex_leave(mem0.mutex);



    }
    sqlite3MemdebugSetType(p, MEMTYPE_SCRATCH);
  }
  assert( sqlite3_mutex_notheld(mem0.mutex) );


#if SQLITE_THREADSAFE==0 && !defined(NDEBUG)
................................................................................
    sqlite3StatusAdd(SQLITE_STATUS_MALLOC_COUNT, -1);
    sqlite3GlobalConfig.m.xFree(p);
    sqlite3_mutex_leave(mem0.mutex);
  }else{
    sqlite3GlobalConfig.m.xFree(p);
  }
}

/*
** Add the size of memory allocation "p" to the count in
** *db->pnBytesFreed.
*/
static SQLITE_NOINLINE void measureAllocationSize(sqlite3 *db, void *p){
  *db->pnBytesFreed += sqlite3DbMallocSize(db,p);
}

/*
** Free memory that might be associated with a particular database
** connection.
*/
void sqlite3DbFree(sqlite3 *db, void *p){
  assert( db==0 || sqlite3_mutex_held(db->mutex) );
  if( p==0 ) return;
  if( db ){
    if( db->pnBytesFreed ){
      measureAllocationSize(db, p);
      return;
    }
    if( isLookaside(db, p) ){
      LookasideSlot *pBuf = (LookasideSlot*)p;
#if SQLITE_DEBUG
      /* Trash all content in the buffer being freed */
      memset(p, 0xaa, db->lookaside.sz);
................................................................................
  va_start(ap, zFormat);
  z = sqlite3VMPrintf(db, zFormat, ap);
  va_end(ap);
  sqlite3DbFree(db, *pz);
  *pz = z;
}

/*
** Take actions at the end of an API call to indicate an OOM error
*/
static SQLITE_NOINLINE int apiOomError(sqlite3 *db){
  db->mallocFailed = 0;
  sqlite3Error(db, SQLITE_NOMEM);
  return SQLITE_NOMEM;
}

/*
** This function must be called before exiting any API function (i.e. 
** returning control to the user) that has called sqlite3_malloc or
** sqlite3_realloc.
**
** The returned value is normally a copy of the second argument to this
................................................................................
*/
int sqlite3ApiExit(sqlite3* db, int rc){
  /* If the db handle is not NULL, then we must hold the connection handle
  ** mutex here. Otherwise the read (and possible write) of db->mallocFailed 
  ** is unsafe, as is the call to sqlite3Error().
  */
  assert( !db || sqlite3_mutex_held(db->mutex) );
  if( db==0 ) return rc & 0xff;
  if( db->mallocFailed || rc==SQLITE_IOERR_NOMEM ){

    return apiOomError(db);

  }
  return rc & db->errMask;
}

      removeFromBlockedList(db);
      addToBlockedList(db);
    }
  }

  leaveMutex();
  assert( !db->mallocFailed );
  sqlite3Error(db, rc, (rc?"database is deadlocked":0));
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

/*
** This function is called while stepping or preparing a statement 
** associated with connection db. The operation will return SQLITE_LOCKED

      removeFromBlockedList(db);
      addToBlockedList(db);
    }
  }

  leaveMutex();
  assert( !db->mallocFailed );
  sqlite3ErrorWithMsg(db, rc, (rc?"database is deadlocked":0));
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

/*
** This function is called while stepping or preparing a statement 
** associated with connection db. The operation will return SQLITE_LOCKED

   && jrnlSize>pPager->journalOff
  ){
    rc = sqlite3OsTruncate(pPager->jfd, pPager->journalOff);
  }
  return rc;
}

/*
** Find a page in the hash table given its page number. Return
** a pointer to the page or NULL if the requested page is not 
** already in memory.
*/
static PgHdr *pager_lookup(Pager *pPager, Pgno pgno){
  PgHdr *p = 0;                     /* Return value */

  /* It is not possible for a call to PcacheFetch() with createFlag==0 to
  ** fail, since no attempt to allocate dynamic memory will be made.
  */
  (void)sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &p);
  return p;
}

/*
** Discard the entire contents of the in-memory page-cache.
*/
static void pager_reset(Pager *pPager){
  sqlite3BackupRestart(pPager->pBackup);
  sqlite3PcacheClear(pPager->pPCache);
}
................................................................................
      }
    }
  }

#ifdef SQLITE_CHECK_PAGES
  sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
  if( pPager->dbSize==0 && sqlite3PcacheRefCount(pPager->pPCache)>0 ){
    PgHdr *p = pager_lookup(pPager, 1);
    if( p ){
      p->pageHash = 0;
      sqlite3PagerUnrefNotNull(p);
    }
  }
#endif

................................................................................
  ** 2008-04-14:  When attempting to vacuum a corrupt database file, it
  ** is possible to fail a statement on a database that does not yet exist.
  ** Do not attempt to write if database file has never been opened.
  */
  if( pagerUseWal(pPager) ){
    pPg = 0;
  }else{
    pPg = pager_lookup(pPager, pgno);
  }
  assert( pPg || !MEMDB );
  assert( pPager->eState!=PAGER_OPEN || pPg==0 );
  PAGERTRACE(("PLAYBACK %d page %d hash(%08x) %s\n",
           PAGERID(pPager), pgno, pager_datahash(pPager->pageSize, (u8*)aData),
           (isMainJrnl?"main-journal":"sub-journal")
  ));
................................................................................
** has ever happened.
*/
DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno){
  PgHdr *pPg = 0;
  assert( pPager!=0 );
  assert( pgno!=0 );
  assert( pPager->pPCache!=0 );
  assert( pPager->eState>=PAGER_READER && pPager->eState!=PAGER_ERROR );
  sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg);
  return pPg;
}

/*
** Release a page reference.
**
................................................................................
  /* Update the database size and return.
  */
  if( pPager->dbSize<pPg->pgno ){
    pPager->dbSize = pPg->pgno;
  }
  return rc;
}




























































































/*
** Mark a data page as writeable. This routine must be called before 
** making changes to a page. The caller must check the return value 
** of this function and be careful not to change any page data unless 
** this routine returns SQLITE_OK.
**
................................................................................
** function also deals with the special case where 2 or more pages
** fit on a single disk sector. In this case all co-resident pages
** must have been written to the journal file before returning.
**
** If an error occurs, SQLITE_NOMEM or an IO error code is returned
** as appropriate. Otherwise, SQLITE_OK.
*/
int sqlite3PagerWrite(DbPage *pDbPage){
  int rc = SQLITE_OK;

  PgHdr *pPg = pDbPage;
  Pager *pPager = pPg->pPager;

  assert( (pPg->flags & PGHDR_MMAP)==0 );
  assert( pPager->eState>=PAGER_WRITER_LOCKED );
  assert( pPager->eState!=PAGER_ERROR );
  assert( assert_pager_state(pPager) );

  if( pPager->sectorSize > (u32)pPager->pageSize ){
    Pgno nPageCount;          /* Total number of pages in database file */
    Pgno pg1;                 /* First page of the sector pPg is located on. */
    int nPage = 0;            /* Number of pages starting at pg1 to journal */
    int ii;                   /* Loop counter */
    int needSync = 0;         /* True if any page has PGHDR_NEED_SYNC */
    Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);

    /* Set the doNotSpill NOSYNC bit to 1. This is because we cannot allow
    ** a journal header to be written between the pages journaled by
    ** this function.
    */
    assert( !MEMDB );
    assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)==0 );
    pPager->doNotSpill |= SPILLFLAG_NOSYNC;

    /* This trick assumes that both the page-size and sector-size are
    ** an integer power of 2. It sets variable pg1 to the identifier
    ** of the first page of the sector pPg is located on.
    */
    pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1;

    nPageCount = pPager->dbSize;
    if( pPg->pgno>nPageCount ){
      nPage = (pPg->pgno - pg1)+1;
    }else if( (pg1+nPagePerSector-1)>nPageCount ){
      nPage = nPageCount+1-pg1;

    }else{
      nPage = nPagePerSector;
    }
    assert(nPage>0);
    assert(pg1<=pPg->pgno);
    assert((pg1+nPage)>pPg->pgno);

    for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){
      Pgno pg = pg1+ii;
      PgHdr *pPage;
      if( pg==pPg->pgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){
        if( pg!=PAGER_MJ_PGNO(pPager) ){
          rc = sqlite3PagerGet(pPager, pg, &pPage);
          if( rc==SQLITE_OK ){
            rc = pager_write(pPage);
            if( pPage->flags&PGHDR_NEED_SYNC ){
              needSync = 1;
            }
            sqlite3PagerUnrefNotNull(pPage);
          }
        }
      }else if( (pPage = pager_lookup(pPager, pg))!=0 ){
        if( pPage->flags&PGHDR_NEED_SYNC ){
          needSync = 1;
        }
        sqlite3PagerUnrefNotNull(pPage);
      }
    }

    /* If the PGHDR_NEED_SYNC flag is set for any of the nPage pages 
    ** starting at pg1, then it needs to be set for all of them. Because
    ** writing to any of these nPage pages may damage the others, the
    ** journal file must contain sync()ed copies of all of them
    ** before any of them can be written out to the database file.
    */
    if( rc==SQLITE_OK && needSync ){
      assert( !MEMDB );
      for(ii=0; ii<nPage; ii++){
        PgHdr *pPage = pager_lookup(pPager, pg1+ii);
        if( pPage ){
          pPage->flags |= PGHDR_NEED_SYNC;
          sqlite3PagerUnrefNotNull(pPage);
        }
      }
    }

    assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)!=0 );
    pPager->doNotSpill &= ~SPILLFLAG_NOSYNC;
  }else{
    rc = pager_write(pDbPage);
  }
  return rc;
}

/*
** Return TRUE if the page given in the argument was previously passed
** to sqlite3PagerWrite().  In other words, return TRUE if it is ok
** to change the content of the page.
*/
................................................................................

  /* If the cache contains a page with page-number pgno, remove it
  ** from its hash chain. Also, if the PGHDR_NEED_SYNC flag was set for 
  ** page pgno before the 'move' operation, it needs to be retained 
  ** for the page moved there.
  */
  pPg->flags &= ~PGHDR_NEED_SYNC;
  pPgOld = pager_lookup(pPager, pgno);
  assert( !pPgOld || pPgOld->nRef==1 );
  if( pPgOld ){
    pPg->flags |= (pPgOld->flags&PGHDR_NEED_SYNC);
    if( MEMDB ){
      /* Do not discard pages from an in-memory database since we might
      ** need to rollback later.  Just move the page out of the way. */
      sqlite3PcacheMove(pPgOld, pPager->dbSize+1);

   && jrnlSize>pPager->journalOff
  ){
    rc = sqlite3OsTruncate(pPager->jfd, pPager->journalOff);
  }
  return rc;
}
















/*
** Discard the entire contents of the in-memory page-cache.
*/
static void pager_reset(Pager *pPager){
  sqlite3BackupRestart(pPager->pBackup);
  sqlite3PcacheClear(pPager->pPCache);
}
................................................................................
      }
    }
  }

#ifdef SQLITE_CHECK_PAGES
  sqlite3PcacheIterateDirty(pPager->pPCache, pager_set_pagehash);
  if( pPager->dbSize==0 && sqlite3PcacheRefCount(pPager->pPCache)>0 ){
    PgHdr *p = sqlite3PagerLookup(pPager, 1);
    if( p ){
      p->pageHash = 0;
      sqlite3PagerUnrefNotNull(p);
    }
  }
#endif

................................................................................
  ** 2008-04-14:  When attempting to vacuum a corrupt database file, it
  ** is possible to fail a statement on a database that does not yet exist.
  ** Do not attempt to write if database file has never been opened.
  */
  if( pagerUseWal(pPager) ){
    pPg = 0;
  }else{
    pPg = sqlite3PagerLookup(pPager, pgno);
  }
  assert( pPg || !MEMDB );
  assert( pPager->eState!=PAGER_OPEN || pPg==0 );
  PAGERTRACE(("PLAYBACK %d page %d hash(%08x) %s\n",
           PAGERID(pPager), pgno, pager_datahash(pPager->pageSize, (u8*)aData),
           (isMainJrnl?"main-journal":"sub-journal")
  ));
................................................................................
** has ever happened.
*/
DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno){
  PgHdr *pPg = 0;
  assert( pPager!=0 );
  assert( pgno!=0 );
  assert( pPager->pPCache!=0 );

  sqlite3PcacheFetch(pPager->pPCache, pgno, 0, &pPg);
  return pPg;
}

/*
** Release a page reference.
**
................................................................................
  /* Update the database size and return.
  */
  if( pPager->dbSize<pPg->pgno ){
    pPager->dbSize = pPg->pgno;
  }
  return rc;
}

/*
** This is a variant of sqlite3PagerWrite() that runs when the sector size
** is larger than the page size.  SQLite makes the (reasonable) assumption that
** all bytes of a sector are written together by hardware.  Hence, all bytes of
** a sector need to be journalled in case of a power loss in the middle of
** a write.
**
** Usually, the sector size is less than or equal to the page size, in which
** case pages can be individually written.  This routine only runs in the exceptional
** case where the page size is smaller than the sector size.
*/
static SQLITE_NOINLINE int pagerWriteLargeSector(PgHdr *pPg){
  int rc = SQLITE_OK;            /* Return code */
  Pgno nPageCount;               /* Total number of pages in database file */
  Pgno pg1;                      /* First page of the sector pPg is located on. */
  int nPage = 0;                 /* Number of pages starting at pg1 to journal */
  int ii;                        /* Loop counter */
  int needSync = 0;              /* True if any page has PGHDR_NEED_SYNC */
  Pager *pPager = pPg->pPager;   /* The pager that owns pPg */
  Pgno nPagePerSector = (pPager->sectorSize/pPager->pageSize);

  /* Set the doNotSpill NOSYNC bit to 1. This is because we cannot allow
  ** a journal header to be written between the pages journaled by
  ** this function.
  */
  assert( !MEMDB );
  assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)==0 );
  pPager->doNotSpill |= SPILLFLAG_NOSYNC;

  /* This trick assumes that both the page-size and sector-size are
  ** an integer power of 2. It sets variable pg1 to the identifier
  ** of the first page of the sector pPg is located on.
  */
  pg1 = ((pPg->pgno-1) & ~(nPagePerSector-1)) + 1;

  nPageCount = pPager->dbSize;
  if( pPg->pgno>nPageCount ){
    nPage = (pPg->pgno - pg1)+1;
  }else if( (pg1+nPagePerSector-1)>nPageCount ){
    nPage = nPageCount+1-pg1;
  }else{
    nPage = nPagePerSector;
  }
  assert(nPage>0);
  assert(pg1<=pPg->pgno);
  assert((pg1+nPage)>pPg->pgno);

  for(ii=0; ii<nPage && rc==SQLITE_OK; ii++){
    Pgno pg = pg1+ii;
    PgHdr *pPage;
    if( pg==pPg->pgno || !sqlite3BitvecTest(pPager->pInJournal, pg) ){
      if( pg!=PAGER_MJ_PGNO(pPager) ){
        rc = sqlite3PagerGet(pPager, pg, &pPage);
        if( rc==SQLITE_OK ){
          rc = pager_write(pPage);
          if( pPage->flags&PGHDR_NEED_SYNC ){
            needSync = 1;
          }
          sqlite3PagerUnrefNotNull(pPage);
        }
      }
    }else if( (pPage = sqlite3PagerLookup(pPager, pg))!=0 ){
      if( pPage->flags&PGHDR_NEED_SYNC ){
        needSync = 1;
      }
      sqlite3PagerUnrefNotNull(pPage);
    }
  }

  /* If the PGHDR_NEED_SYNC flag is set for any of the nPage pages 
  ** starting at pg1, then it needs to be set for all of them. Because
  ** writing to any of these nPage pages may damage the others, the
  ** journal file must contain sync()ed copies of all of them
  ** before any of them can be written out to the database file.
  */
  if( rc==SQLITE_OK && needSync ){
    assert( !MEMDB );
    for(ii=0; ii<nPage; ii++){
      PgHdr *pPage = sqlite3PagerLookup(pPager, pg1+ii);
      if( pPage ){
        pPage->flags |= PGHDR_NEED_SYNC;
        sqlite3PagerUnrefNotNull(pPage);
      }
    }
  }

  assert( (pPager->doNotSpill & SPILLFLAG_NOSYNC)!=0 );
  pPager->doNotSpill &= ~SPILLFLAG_NOSYNC;
  return rc;
}

/*
** Mark a data page as writeable. This routine must be called before 
** making changes to a page. The caller must check the return value 
** of this function and be careful not to change any page data unless 
** this routine returns SQLITE_OK.
**
................................................................................
** function also deals with the special case where 2 or more pages
** fit on a single disk sector. In this case all co-resident pages
** must have been written to the journal file before returning.
**
** If an error occurs, SQLITE_NOMEM or an IO error code is returned
** as appropriate. Otherwise, SQLITE_OK.
*/
int sqlite3PagerWrite(PgHdr *pPg){





  assert( (pPg->flags & PGHDR_MMAP)==0 );
  assert( pPg->pPager->eState>=PAGER_WRITER_LOCKED );
  assert( pPg->pPager->eState!=PAGER_ERROR );
  assert( assert_pager_state(pPg->pPager) );

  if( pPg->pPager->sectorSize > (u32)pPg->pPager->pageSize ){


























    return pagerWriteLargeSector(pPg);
  }else{













    return pager_write(pPg);


  }


































}

/*
** Return TRUE if the page given in the argument was previously passed
** to sqlite3PagerWrite().  In other words, return TRUE if it is ok
** to change the content of the page.
*/
................................................................................

  /* If the cache contains a page with page-number pgno, remove it
  ** from its hash chain. Also, if the PGHDR_NEED_SYNC flag was set for 
  ** page pgno before the 'move' operation, it needs to be retained 
  ** for the page moved there.
  */
  pPg->flags &= ~PGHDR_NEED_SYNC;
  pPgOld = sqlite3PagerLookup(pPager, pgno);
  assert( !pPgOld || pPgOld->nRef==1 );
  if( pPgOld ){
    pPg->flags |= (pPgOld->flags&PGHDR_NEED_SYNC);
    if( MEMDB ){
      /* Do not discard pages from an in-memory database since we might
      ** need to rollback later.  Just move the page out of the way. */
      sqlite3PcacheMove(pPgOld, pPager->dbSize+1);

  for(p=pCache->pDirtyTail; p!=pCache->pSynced; p=p->pDirtyPrev){
    assert( p->nRef || (p->flags&PGHDR_NEED_SYNC) );
  }
  return (p==0 || p->nRef || (p->flags&PGHDR_NEED_SYNC)==0);
}
#endif /* !NDEBUG && SQLITE_ENABLE_EXPENSIVE_ASSERT */






/*
** Remove page pPage from the list of dirty pages.




*/
static void pcacheRemoveFromDirtyList(PgHdr *pPage){
  PCache *p = pPage->pCache;


  assert( pPage->pDirtyNext || pPage==p->pDirtyTail );
  assert( pPage->pDirtyPrev || pPage==p->pDirty );

  /* Update the PCache1.pSynced variable if necessary. */
  if( p->pSynced==pPage ){
    PgHdr *pSynced = pPage->pDirtyPrev;
    while( pSynced && (pSynced->flags&PGHDR_NEED_SYNC) ){
      pSynced = pSynced->pDirtyPrev;
    }
    p->pSynced = pSynced;
  }

  if( pPage->pDirtyNext ){
    pPage->pDirtyNext->pDirtyPrev = pPage->pDirtyPrev;
  }else{
    assert( pPage==p->pDirtyTail );
    p->pDirtyTail = pPage->pDirtyPrev;
  }
  if( pPage->pDirtyPrev ){
    pPage->pDirtyPrev->pDirtyNext = pPage->pDirtyNext;
  }else{
    assert( pPage==p->pDirty );
    p->pDirty = pPage->pDirtyNext;
    if( p->pDirty==0 && p->bPurgeable ){
      assert( p->eCreate==1 );
      p->eCreate = 2;
    }
  }
  pPage->pDirtyNext = 0;
  pPage->pDirtyPrev = 0;

  expensive_assert( pcacheCheckSynced(p) );
}

/*
** Add page pPage to the head of the dirty list (PCache1.pDirty is set to
** pPage).
*/
static void pcacheAddToDirtyList(PgHdr *pPage){
  PCache *p = pPage->pCache;


  assert( pPage->pDirtyNext==0 && pPage->pDirtyPrev==0 && p->pDirty!=pPage );

  pPage->pDirtyNext = p->pDirty;
  if( pPage->pDirtyNext ){
    assert( pPage->pDirtyNext->pDirtyPrev==0 );
    pPage->pDirtyNext->pDirtyPrev = pPage;
  }else if( p->bPurgeable ){
    assert( p->eCreate==2 );
    p->eCreate = 1;
  }
  p->pDirty = pPage;
  if( !p->pDirtyTail ){
    p->pDirtyTail = pPage;
  }
  if( !p->pSynced && 0==(pPage->flags&PGHDR_NEED_SYNC) ){
    p->pSynced = pPage;
  }
  expensive_assert( pcacheCheckSynced(p) );
}


/*
** Wrapper around the pluggable caches xUnpin method. If the cache is
** being used for an in-memory database, this function is a no-op.
*/
static void pcacheUnpin(PgHdr *p){
  PCache *pCache = p->pCache;
  if( pCache->bPurgeable ){
    if( p->pgno==1 ){
      pCache->pPage1 = 0;
    }
    sqlite3GlobalConfig.pcache2.xUnpin(pCache->pCache, p->pPage, 0);
  }
}

/*************************************************** General Interfaces ******
**
** Initialize and shutdown the page cache subsystem. Neither of these 
** functions are threadsafe.
................................................................................
  return (pPgHdr==0 && eCreate) ? SQLITE_NOMEM : SQLITE_OK;
}

/*
** Decrement the reference count on a page. If the page is clean and the
** reference count drops to 0, then it is made elible for recycling.
*/
void sqlite3PcacheRelease(PgHdr *p){
  assert( p->nRef>0 );
  p->nRef--;
  if( p->nRef==0 ){
    PCache *pCache = p->pCache;
    pCache->nRef--;
    if( (p->flags&PGHDR_DIRTY)==0 ){
      pcacheUnpin(p);
    }else{
      /* Move the page to the head of the dirty list. */
      pcacheRemoveFromDirtyList(p);
      pcacheAddToDirtyList(p);
    }
  }
}

/*
** Increase the reference count of a supplied page by 1.
*/
................................................................................

/*
** Drop a page from the cache. There must be exactly one reference to the
** page. This function deletes that reference, so after it returns the
** page pointed to by p is invalid.
*/
void sqlite3PcacheDrop(PgHdr *p){
  PCache *pCache;
  assert( p->nRef==1 );
  if( p->flags&PGHDR_DIRTY ){
    pcacheRemoveFromDirtyList(p);

  }
  pCache = p->pCache;
  pCache->nRef--;
  if( p->pgno==1 ){
    pCache->pPage1 = 0;
  }
  sqlite3GlobalConfig.pcache2.xUnpin(pCache->pCache, p->pPage, 1);
}

/*
** Make sure the page is marked as dirty. If it isn't dirty already,
** make it so.
*/
void sqlite3PcacheMakeDirty(PgHdr *p){
  p->flags &= ~PGHDR_DONT_WRITE;
  assert( p->nRef>0 );
  if( 0==(p->flags & PGHDR_DIRTY) ){
    p->flags |= PGHDR_DIRTY;
    pcacheAddToDirtyList( p);
  }
}

/*
** Make sure the page is marked as clean. If it isn't clean already,
** make it so.
*/
void sqlite3PcacheMakeClean(PgHdr *p){
  if( (p->flags & PGHDR_DIRTY) ){
    pcacheRemoveFromDirtyList(p);
    p->flags &= ~(PGHDR_DIRTY|PGHDR_NEED_SYNC);
    if( p->nRef==0 ){
      pcacheUnpin(p);
    }
  }
}

................................................................................
void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
  PCache *pCache = p->pCache;
  assert( p->nRef>0 );
  assert( newPgno>0 );
  sqlite3GlobalConfig.pcache2.xRekey(pCache->pCache, p->pPage, p->pgno,newPgno);
  p->pgno = newPgno;
  if( (p->flags&PGHDR_DIRTY) && (p->flags&PGHDR_NEED_SYNC) ){
    pcacheRemoveFromDirtyList(p);
    pcacheAddToDirtyList(p);
  }
}

/*
** Drop every cache entry whose page number is greater than "pgno". The
** caller must ensure that there are no outstanding references to any pages
** other than page 1 with a page number greater than pgno.

  for(p=pCache->pDirtyTail; p!=pCache->pSynced; p=p->pDirtyPrev){
    assert( p->nRef || (p->flags&PGHDR_NEED_SYNC) );
  }
  return (p==0 || p->nRef || (p->flags&PGHDR_NEED_SYNC)==0);
}
#endif /* !NDEBUG && SQLITE_ENABLE_EXPENSIVE_ASSERT */

/* Allowed values for second argument to pcacheManageDirtyList() */
#define PCACHE_DIRTYLIST_REMOVE   1    /* Remove pPage from dirty list */
#define PCACHE_DIRTYLIST_ADD      2    /* Add pPage to the dirty list */
#define PCACHE_DIRTYLIST_FRONT    3    /* Move pPage to the front of the list */

/*

** Manage pPage's participation on the dirty list.  Bits of the addRemove
** argument determines what operation to do.  The 0x01 bit means first
** remove pPage from the dirty list.  The 0x02 means add pPage back to
** the dirty list.  Doing both moves pPage to the front of the dirty list.
*/
static void pcacheManageDirtyList(PgHdr *pPage, u8 addRemove){
  PCache *p = pPage->pCache;

  if( addRemove & PCACHE_DIRTYLIST_REMOVE ){
    assert( pPage->pDirtyNext || pPage==p->pDirtyTail );
    assert( pPage->pDirtyPrev || pPage==p->pDirty );
  
    /* Update the PCache1.pSynced variable if necessary. */
    if( p->pSynced==pPage ){
      PgHdr *pSynced = pPage->pDirtyPrev;
      while( pSynced && (pSynced->flags&PGHDR_NEED_SYNC) ){
        pSynced = pSynced->pDirtyPrev;
      }
      p->pSynced = pSynced;
    }
  
    if( pPage->pDirtyNext ){
      pPage->pDirtyNext->pDirtyPrev = pPage->pDirtyPrev;
    }else{
      assert( pPage==p->pDirtyTail );
      p->pDirtyTail = pPage->pDirtyPrev;
    }
    if( pPage->pDirtyPrev ){
      pPage->pDirtyPrev->pDirtyNext = pPage->pDirtyNext;
    }else{
      assert( pPage==p->pDirty );
      p->pDirty = pPage->pDirtyNext;
      if( p->pDirty==0 && p->bPurgeable ){
        assert( p->eCreate==1 );
        p->eCreate = 2;
      }
    }
    pPage->pDirtyNext = 0;
    pPage->pDirtyPrev = 0;

    expensive_assert( pcacheCheckSynced(p) );
  }








  if( addRemove & PCACHE_DIRTYLIST_ADD ){
    assert( pPage->pDirtyNext==0 && pPage->pDirtyPrev==0 && p->pDirty!=pPage );
  
    pPage->pDirtyNext = p->pDirty;
    if( pPage->pDirtyNext ){
      assert( pPage->pDirtyNext->pDirtyPrev==0 );
      pPage->pDirtyNext->pDirtyPrev = pPage;
    }else if( p->bPurgeable ){
      assert( p->eCreate==2 );
      p->eCreate = 1;
    }
    p->pDirty = pPage;
    if( !p->pDirtyTail ){
      p->pDirtyTail = pPage;
    }
    if( !p->pSynced && 0==(pPage->flags&PGHDR_NEED_SYNC) ){
      p->pSynced = pPage;
    }
    expensive_assert( pcacheCheckSynced(p) );
  }
}

/*
** Wrapper around the pluggable caches xUnpin method. If the cache is
** being used for an in-memory database, this function is a no-op.
*/
static void pcacheUnpin(PgHdr *p){

  if( p->pCache->bPurgeable ){
    if( p->pgno==1 ){
      p->pCache->pPage1 = 0;
    }
    sqlite3GlobalConfig.pcache2.xUnpin(p->pCache->pCache, p->pPage, 0);
  }
}

/*************************************************** General Interfaces ******
**
** Initialize and shutdown the page cache subsystem. Neither of these 
** functions are threadsafe.
................................................................................
  return (pPgHdr==0 && eCreate) ? SQLITE_NOMEM : SQLITE_OK;
}

/*
** Decrement the reference count on a page. If the page is clean and the
** reference count drops to 0, then it is made elible for recycling.
*/
void SQLITE_NOINLINE sqlite3PcacheRelease(PgHdr *p){
  assert( p->nRef>0 );
  p->nRef--;
  if( p->nRef==0 ){

    p->pCache->nRef--;
    if( (p->flags&PGHDR_DIRTY)==0 ){
      pcacheUnpin(p);
    }else{
      /* Move the page to the head of the dirty list. */
      pcacheManageDirtyList(p, PCACHE_DIRTYLIST_FRONT);

    }
  }
}

/*
** Increase the reference count of a supplied page by 1.
*/
................................................................................

/*
** Drop a page from the cache. There must be exactly one reference to the
** page. This function deletes that reference, so after it returns the
** page pointed to by p is invalid.
*/
void sqlite3PcacheDrop(PgHdr *p){

  assert( p->nRef==1 );
  if( p->flags&PGHDR_DIRTY ){

    pcacheManageDirtyList(p, PCACHE_DIRTYLIST_REMOVE);
  }

  p->pCache->nRef--;
  if( p->pgno==1 ){
    p->pCache->pPage1 = 0;
  }
  sqlite3GlobalConfig.pcache2.xUnpin(p->pCache->pCache, p->pPage, 1);
}

/*
** Make sure the page is marked as dirty. If it isn't dirty already,
** make it so.
*/
void sqlite3PcacheMakeDirty(PgHdr *p){
  p->flags &= ~PGHDR_DONT_WRITE;
  assert( p->nRef>0 );
  if( 0==(p->flags & PGHDR_DIRTY) ){
    p->flags |= PGHDR_DIRTY;
    pcacheManageDirtyList(p, PCACHE_DIRTYLIST_ADD);
  }
}

/*
** Make sure the page is marked as clean. If it isn't clean already,
** make it so.
*/
void sqlite3PcacheMakeClean(PgHdr *p){
  if( (p->flags & PGHDR_DIRTY) ){
    pcacheManageDirtyList(p, PCACHE_DIRTYLIST_REMOVE);
    p->flags &= ~(PGHDR_DIRTY|PGHDR_NEED_SYNC);
    if( p->nRef==0 ){
      pcacheUnpin(p);
    }
  }
}

................................................................................
void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
  PCache *pCache = p->pCache;
  assert( p->nRef>0 );
  assert( newPgno>0 );
  sqlite3GlobalConfig.pcache2.xRekey(pCache->pCache, p->pPage, p->pgno,newPgno);
  p->pgno = newPgno;
  if( (p->flags&PGHDR_DIRTY) && (p->flags&PGHDR_NEED_SYNC) ){
    pcacheManageDirtyList(p, PCACHE_DIRTYLIST_FRONT);

  }
}

/*
** Drop every cache entry whose page number is greater than "pgno". The
** caller must ensure that there are no outstanding references to any pages
** other than page 1 with a page number greater than pgno.

/*
** This function is used to resize the hash table used by the cache passed
** as the first argument.
**
** The PCache mutex must be held when this function is called.
*/
static int pcache1ResizeHash(PCache1 *p){
  PgHdr1 **apNew;
  unsigned int nNew;
  unsigned int i;

  assert( sqlite3_mutex_held(p->pGroup->mutex) );

  nNew = p->nHash*2;
................................................................................
        apNew[h] = pPage;
      }
    }
    sqlite3_free(p->apHash);
    p->apHash = apNew;
    p->nHash = nNew;
  }

  return (p->apHash ? SQLITE_OK : SQLITE_NOMEM);
}

/*
** This function is used internally to remove the page pPage from the 
** PGroup LRU list, if is part of it. If pPage is not part of the PGroup
** LRU list, then this function is a no-op.
**
................................................................................
*/
static void pcache1Shutdown(void *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  assert( pcache1.isInit!=0 );
  memset(&pcache1, 0, sizeof(pcache1));
}




/*
** Implementation of the sqlite3_pcache.xCreate method.
**
** Allocate a new cache.
*/
static sqlite3_pcache *pcache1Create(int szPage, int szExtra, int bPurgeable){
  PCache1 *pCache;      /* The newly created page cache */
................................................................................
    }else{
      pGroup = &pcache1.grp;
    }
    pCache->pGroup = pGroup;
    pCache->szPage = szPage;
    pCache->szExtra = szExtra;
    pCache->bPurgeable = (bPurgeable ? 1 : 0);


    if( bPurgeable ){
      pCache->nMin = 10;
      pcache1EnterMutex(pGroup);
      pGroup->nMinPage += pCache->nMin;
      pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;

      pcache1LeaveMutex(pGroup);



    }
  }
  return (sqlite3_pcache *)pCache;
}

/*
** Implementation of the sqlite3_pcache.xCachesize method. 
................................................................................
  PCache1 *pCache = (PCache1*)p;
  pcache1EnterMutex(pCache->pGroup);
  n = pCache->nPage;
  pcache1LeaveMutex(pCache->pGroup);
  return n;
}


























































































/*
** Implementation of the sqlite3_pcache.xFetch method. 
**
** Fetch a page by key value.
**
** Whether or not a new page may be allocated by this function depends on
** the value of the createFlag argument.  0 means do not allocate a new
................................................................................
**   5. Otherwise, allocate and return a new page buffer.
*/
static sqlite3_pcache_page *pcache1Fetch(
  sqlite3_pcache *p, 
  unsigned int iKey, 
  int createFlag
){
  unsigned int nPinned;
  PCache1 *pCache = (PCache1 *)p;
  PGroup *pGroup;
  PgHdr1 *pPage = 0;

  assert( offsetof(PgHdr1,page)==0 );
  assert( pCache->bPurgeable || createFlag!=1 );
  assert( pCache->bPurgeable || pCache->nMin==0 );
  assert( pCache->bPurgeable==0 || pCache->nMin==10 );
  assert( pCache->nMin==0 || pCache->bPurgeable );

  pcache1EnterMutex(pGroup = pCache->pGroup);

  /* Step 1: Search the hash table for an existing entry. */
  if( pCache->nHash>0 ){
    unsigned int h = iKey % pCache->nHash;
    for(pPage=pCache->apHash[h]; pPage&&pPage->iKey!=iKey; pPage=pPage->pNext);
  }

  /* Step 2: Abort if no existing page is found and createFlag is 0 */
  if( pPage ){
    if( !pPage->isPinned ) pcache1PinPage(pPage);
    goto fetch_out;
  }
  if( createFlag==0 ){
    goto fetch_out;


  }

  /* The pGroup local variable will normally be initialized by the
  ** pcache1EnterMutex() macro above.  But if SQLITE_MUTEX_OMIT is defined,
  ** then pcache1EnterMutex() is a no-op, so we have to initialize the
  ** local variable here.  Delaying the initialization of pGroup is an
  ** optimization:  The common case is to exit the module before reaching
  ** this point.
  */
#ifdef SQLITE_MUTEX_OMIT
  pGroup = pCache->pGroup;
#endif

  /* Step 3: Abort if createFlag is 1 but the cache is nearly full */
  assert( pCache->nPage >= pCache->nRecyclable );
  nPinned = pCache->nPage - pCache->nRecyclable;
  assert( pGroup->mxPinned == pGroup->nMaxPage + 10 - pGroup->nMinPage );
  assert( pCache->n90pct == pCache->nMax*9/10 );
  if( createFlag==1 && (
        nPinned>=pGroup->mxPinned
     || nPinned>=pCache->n90pct
     || pcache1UnderMemoryPressure(pCache)
  )){
    goto fetch_out;
  }

  if( pCache->nPage>=pCache->nHash && pcache1ResizeHash(pCache) ){
    goto fetch_out;
  }
  assert( pCache->nHash>0 && pCache->apHash );

  /* Step 4. Try to recycle a page. */
  if( pCache->bPurgeable && pGroup->pLruTail && (
         (pCache->nPage+1>=pCache->nMax)
      || pGroup->nCurrentPage>=pGroup->nMaxPage
      || pcache1UnderMemoryPressure(pCache)
  )){
    PCache1 *pOther;
    pPage = pGroup->pLruTail;
    assert( pPage->isPinned==0 );
    pcache1RemoveFromHash(pPage);
    pcache1PinPage(pPage);
    pOther = pPage->pCache;

    /* We want to verify that szPage and szExtra are the same for pOther
    ** and pCache.  Assert that we can verify this by comparing sums. */
    assert( (pCache->szPage & (pCache->szPage-1))==0 && pCache->szPage>=512 );
    assert( pCache->szExtra<512 );
    assert( (pOther->szPage & (pOther->szPage-1))==0 && pOther->szPage>=512 );
    assert( pOther->szExtra<512 );

    if( pOther->szPage+pOther->szExtra != pCache->szPage+pCache->szExtra ){
      pcache1FreePage(pPage);
      pPage = 0;
    }else{
      pGroup->nCurrentPage -= (pOther->bPurgeable - pCache->bPurgeable);
    }
  }

  /* Step 5. If a usable page buffer has still not been found, 
  ** attempt to allocate a new one. 
  */
  if( !pPage ){
    if( createFlag==1 ) sqlite3BeginBenignMalloc();
    pPage = pcache1AllocPage(pCache);
    if( createFlag==1 ) sqlite3EndBenignMalloc();
  }

  if( pPage ){
    unsigned int h = iKey % pCache->nHash;
    pCache->nPage++;
    pPage->iKey = iKey;
    pPage->pNext = pCache->apHash[h];
    pPage->pCache = pCache;
    pPage->pLruPrev = 0;
    pPage->pLruNext = 0;
    pPage->isPinned = 1;
    *(void **)pPage->page.pExtra = 0;
    pCache->apHash[h] = pPage;
  }

fetch_out:
  if( pPage && iKey>pCache->iMaxKey ){
    pCache->iMaxKey = iKey;
  }
  pcache1LeaveMutex(pGroup);
  return (sqlite3_pcache_page*)pPage;
}


/*
** Implementation of the sqlite3_pcache.xUnpin method.
**

/*
** This function is used to resize the hash table used by the cache passed
** as the first argument.
**
** The PCache mutex must be held when this function is called.
*/
static void pcache1ResizeHash(PCache1 *p){
  PgHdr1 **apNew;
  unsigned int nNew;
  unsigned int i;

  assert( sqlite3_mutex_held(p->pGroup->mutex) );

  nNew = p->nHash*2;
................................................................................
        apNew[h] = pPage;
      }
    }
    sqlite3_free(p->apHash);
    p->apHash = apNew;
    p->nHash = nNew;
  }


}

/*
** This function is used internally to remove the page pPage from the 
** PGroup LRU list, if is part of it. If pPage is not part of the PGroup
** LRU list, then this function is a no-op.
**
................................................................................
*/
static void pcache1Shutdown(void *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  assert( pcache1.isInit!=0 );
  memset(&pcache1, 0, sizeof(pcache1));
}

/* forward declaration */
static void pcache1Destroy(sqlite3_pcache *p);

/*
** Implementation of the sqlite3_pcache.xCreate method.
**
** Allocate a new cache.
*/
static sqlite3_pcache *pcache1Create(int szPage, int szExtra, int bPurgeable){
  PCache1 *pCache;      /* The newly created page cache */
................................................................................
    }else{
      pGroup = &pcache1.grp;
    }
    pCache->pGroup = pGroup;
    pCache->szPage = szPage;
    pCache->szExtra = szExtra;
    pCache->bPurgeable = (bPurgeable ? 1 : 0);
    pcache1EnterMutex(pGroup);
    pcache1ResizeHash(pCache);
    if( bPurgeable ){
      pCache->nMin = 10;

      pGroup->nMinPage += pCache->nMin;
      pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
    }
    pcache1LeaveMutex(pGroup);
    if( pCache->nHash==0 ){
      pcache1Destroy((sqlite3_pcache*)pCache);
      pCache = 0;
    }
  }
  return (sqlite3_pcache *)pCache;
}

/*
** Implementation of the sqlite3_pcache.xCachesize method. 
................................................................................
  PCache1 *pCache = (PCache1*)p;
  pcache1EnterMutex(pCache->pGroup);
  n = pCache->nPage;
  pcache1LeaveMutex(pCache->pGroup);
  return n;
}


/*
** Implement steps 3, 4, and 5 of the pcache1Fetch() algorithm described
** in the header of the pcache1Fetch() procedure.
**
** This steps are broken out into a separate procedure because they are
** usually not needed, and by avoiding the stack initialization required
** for these steps, the main pcache1Fetch() procedure can run faster.
*/
static SQLITE_NOINLINE PgHdr1 *pcache1FetchStage2(
  PCache1 *pCache, 
  unsigned int iKey, 
  int createFlag
){
  unsigned int nPinned;
  PGroup *pGroup = pCache->pGroup;
  PgHdr1 *pPage = 0;

  /* Step 3: Abort if createFlag is 1 but the cache is nearly full */
  assert( pCache->nPage >= pCache->nRecyclable );
  nPinned = pCache->nPage - pCache->nRecyclable;
  assert( pGroup->mxPinned == pGroup->nMaxPage + 10 - pGroup->nMinPage );
  assert( pCache->n90pct == pCache->nMax*9/10 );
  if( createFlag==1 && (
        nPinned>=pGroup->mxPinned
     || nPinned>=pCache->n90pct
     || pcache1UnderMemoryPressure(pCache)
  )){
    return 0;
  }

  if( pCache->nPage>=pCache->nHash ) pcache1ResizeHash(pCache);
  assert( pCache->nHash>0 && pCache->apHash );

  /* Step 4. Try to recycle a page. */
  if( pCache->bPurgeable && pGroup->pLruTail && (
         (pCache->nPage+1>=pCache->nMax)
      || pGroup->nCurrentPage>=pGroup->nMaxPage
      || pcache1UnderMemoryPressure(pCache)
  )){
    PCache1 *pOther;
    pPage = pGroup->pLruTail;
    assert( pPage->isPinned==0 );
    pcache1RemoveFromHash(pPage);
    pcache1PinPage(pPage);
    pOther = pPage->pCache;

    /* We want to verify that szPage and szExtra are the same for pOther
    ** and pCache.  Assert that we can verify this by comparing sums. */
    assert( (pCache->szPage & (pCache->szPage-1))==0 && pCache->szPage>=512 );
    assert( pCache->szExtra<512 );
    assert( (pOther->szPage & (pOther->szPage-1))==0 && pOther->szPage>=512 );
    assert( pOther->szExtra<512 );

    if( pOther->szPage+pOther->szExtra != pCache->szPage+pCache->szExtra ){
      pcache1FreePage(pPage);
      pPage = 0;
    }else{
      pGroup->nCurrentPage -= (pOther->bPurgeable - pCache->bPurgeable);
    }
  }

  /* Step 5. If a usable page buffer has still not been found, 
  ** attempt to allocate a new one. 
  */
  if( !pPage ){
    if( createFlag==1 ) sqlite3BeginBenignMalloc();
    pPage = pcache1AllocPage(pCache);
    if( createFlag==1 ) sqlite3EndBenignMalloc();
  }

  if( pPage ){
    unsigned int h = iKey % pCache->nHash;
    pCache->nPage++;
    pPage->iKey = iKey;
    pPage->pNext = pCache->apHash[h];
    pPage->pCache = pCache;
    pPage->pLruPrev = 0;
    pPage->pLruNext = 0;
    pPage->isPinned = 1;
    *(void **)pPage->page.pExtra = 0;
    pCache->apHash[h] = pPage;
    if( iKey>pCache->iMaxKey ){
      pCache->iMaxKey = iKey;
    }
  }
  return pPage;
}

/*
** Implementation of the sqlite3_pcache.xFetch method. 
**
** Fetch a page by key value.
**
** Whether or not a new page may be allocated by this function depends on
** the value of the createFlag argument.  0 means do not allocate a new
................................................................................
**   5. Otherwise, allocate and return a new page buffer.
*/
static sqlite3_pcache_page *pcache1Fetch(
  sqlite3_pcache *p, 
  unsigned int iKey, 
  int createFlag
){

  PCache1 *pCache = (PCache1 *)p;

  PgHdr1 *pPage = 0;

  assert( offsetof(PgHdr1,page)==0 );
  assert( pCache->bPurgeable || createFlag!=1 );
  assert( pCache->bPurgeable || pCache->nMin==0 );
  assert( pCache->bPurgeable==0 || pCache->nMin==10 );
  assert( pCache->nMin==0 || pCache->bPurgeable );
  assert( pCache->nHash>0 );
  pcache1EnterMutex(pCache->pGroup);

  /* Step 1: Search the hash table for an existing entry. */

  pPage = pCache->apHash[iKey % pCache->nHash];
  while( pPage && pPage->iKey!=iKey ){ pPage = pPage->pNext; }


  /* Step 2: Abort if no existing page is found and createFlag is 0 */
  if( pPage ){
    if( !pPage->isPinned ) pcache1PinPage(pPage);


  }else if( createFlag ){

    /* Steps 3, 4, and 5 implemented by this subroutine */
    pPage = pcache1FetchStage2(pCache, iKey, createFlag);
  }


















































































  assert( pPage==0 || pCache->iMaxKey>=iKey );

  pcache1LeaveMutex(pCache->pGroup);
  return (sqlite3_pcache_page*)pPage;
}


/*
** Implementation of the sqlite3_pcache.xUnpin method.
**

  for(i=0; i<db->nDb; i++) {
    Btree *pBt = db->aDb[i].pBt;
    if( pBt ){
      assert( sqlite3BtreeHoldsMutex(pBt) );
      rc = sqlite3BtreeSchemaLocked(pBt);
      if( rc ){
        const char *zDb = db->aDb[i].zName;
        sqlite3Error(db, rc, "database schema is locked: %s", zDb);
        testcase( db->flags & SQLITE_ReadUncommitted );
        goto end_prepare;
      }
    }
  }

  sqlite3VtabUnlockList(db);
................................................................................
  pParse->nQueryLoop = 0;  /* Logarithmic, so 0 really means 1 */
  if( nBytes>=0 && (nBytes==0 || zSql[nBytes-1]!=0) ){
    char *zSqlCopy;
    int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
    testcase( nBytes==mxLen );
    testcase( nBytes==mxLen+1 );
    if( nBytes>mxLen ){
      sqlite3Error(db, SQLITE_TOOBIG, "statement too long");
      rc = sqlite3ApiExit(db, SQLITE_TOOBIG);
      goto end_prepare;
    }
    zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
    if( zSqlCopy ){
      sqlite3RunParser(pParse, zSqlCopy, &zErrMsg);
      sqlite3DbFree(db, zSqlCopy);
................................................................................
    sqlite3VdbeFinalize(pParse->pVdbe);
    assert(!(*ppStmt));
  }else{
    *ppStmt = (sqlite3_stmt*)pParse->pVdbe;
  }

  if( zErrMsg ){
    sqlite3Error(db, rc, "%s", zErrMsg);
    sqlite3DbFree(db, zErrMsg);
  }else{
    sqlite3Error(db, rc, 0);
  }

  /* Delete any TriggerPrg structures allocated while parsing this statement. */
  while( pParse->pTriggerPrg ){
    TriggerPrg *pT = pParse->pTriggerPrg;
    pParse->pTriggerPrg = pT->pNext;
    sqlite3DbFree(db, pT);

  for(i=0; i<db->nDb; i++) {
    Btree *pBt = db->aDb[i].pBt;
    if( pBt ){
      assert( sqlite3BtreeHoldsMutex(pBt) );
      rc = sqlite3BtreeSchemaLocked(pBt);
      if( rc ){
        const char *zDb = db->aDb[i].zName;
        sqlite3ErrorWithMsg(db, rc, "database schema is locked: %s", zDb);
        testcase( db->flags & SQLITE_ReadUncommitted );
        goto end_prepare;
      }
    }
  }

  sqlite3VtabUnlockList(db);
................................................................................
  pParse->nQueryLoop = 0;  /* Logarithmic, so 0 really means 1 */
  if( nBytes>=0 && (nBytes==0 || zSql[nBytes-1]!=0) ){
    char *zSqlCopy;
    int mxLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
    testcase( nBytes==mxLen );
    testcase( nBytes==mxLen+1 );
    if( nBytes>mxLen ){
      sqlite3ErrorWithMsg(db, SQLITE_TOOBIG, "statement too long");
      rc = sqlite3ApiExit(db, SQLITE_TOOBIG);
      goto end_prepare;
    }
    zSqlCopy = sqlite3DbStrNDup(db, zSql, nBytes);
    if( zSqlCopy ){
      sqlite3RunParser(pParse, zSqlCopy, &zErrMsg);
      sqlite3DbFree(db, zSqlCopy);
................................................................................
    sqlite3VdbeFinalize(pParse->pVdbe);
    assert(!(*ppStmt));
  }else{
    *ppStmt = (sqlite3_stmt*)pParse->pVdbe;
  }

  if( zErrMsg ){
    sqlite3ErrorWithMsg(db, rc, "%s", zErrMsg);
    sqlite3DbFree(db, zErrMsg);
  }else{
    sqlite3Error(db, rc);
  }

  /* Delete any TriggerPrg structures allocated while parsing this statement. */
  while( pParse->pTriggerPrg ){
    TriggerPrg *pT = pParse->pTriggerPrg;
    pParse->pTriggerPrg = pT->pNext;
    sqlite3DbFree(db, pT);

** The StrAccum "p" is not large enough to accept N new bytes of z[].
** So enlarge if first, then do the append.
**
** This is a helper routine to sqlite3StrAccumAppend() that does special-case
** work (enlarging the buffer) using tail recursion, so that the
** sqlite3StrAccumAppend() routine can use fast calling semantics.
*/
static void enlargeAndAppend(StrAccum *p, const char *z, int N){
  N = sqlite3StrAccumEnlarge(p, N);
  if( N>0 ){
    memcpy(&p->zText[p->nChar], z, N);
    p->nChar += N;
  }
}

................................................................................
void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
  assert( z!=0 );
  assert( p->zText!=0 || p->nChar==0 || p->accError );
  assert( N>=0 );
  assert( p->accError==0 || p->nAlloc==0 );
  if( p->nChar+N >= p->nAlloc ){
    enlargeAndAppend(p,z,N);
    return;
  }
  assert( p->zText );
  memcpy(&p->zText[p->nChar], z, N);
  p->nChar += N;


}

/*
** Append the complete text of zero-terminated string z[] to the p string.
*/
void sqlite3StrAccumAppendAll(StrAccum *p, const char *z){
  sqlite3StrAccumAppend(p, z, sqlite3Strlen30(z));

** The StrAccum "p" is not large enough to accept N new bytes of z[].
** So enlarge if first, then do the append.
**
** This is a helper routine to sqlite3StrAccumAppend() that does special-case
** work (enlarging the buffer) using tail recursion, so that the
** sqlite3StrAccumAppend() routine can use fast calling semantics.
*/
static void SQLITE_NOINLINE enlargeAndAppend(StrAccum *p, const char *z, int N){
  N = sqlite3StrAccumEnlarge(p, N);
  if( N>0 ){
    memcpy(&p->zText[p->nChar], z, N);
    p->nChar += N;
  }
}

................................................................................
void sqlite3StrAccumAppend(StrAccum *p, const char *z, int N){
  assert( z!=0 );
  assert( p->zText!=0 || p->nChar==0 || p->accError );
  assert( N>=0 );
  assert( p->accError==0 || p->nAlloc==0 );
  if( p->nChar+N >= p->nAlloc ){
    enlargeAndAppend(p,z,N);
  }else{

    assert( p->zText );

    p->nChar += N;
    memcpy(&p->zText[p->nChar-N], z, N);
  }
}

/*
** Append the complete text of zero-terminated string z[] to the p string.
*/
void sqlite3StrAccumAppendAll(StrAccum *p, const char *z){
  sqlite3StrAccumAppend(p, z, sqlite3Strlen30(z));

# define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
#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













/*
** 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.
................................................................................
LogEst sqlite3LogEstFromDouble(double);
#endif
u64 sqlite3LogEstToInt(LogEst);

/*
** Routines to read and write variable-length integers.  These used to
** be defined locally, but now we use the varint routines in the util.c
** file.  Code should use the MACRO forms below, as the Varint32 versions
** are coded to assume the single byte case is already handled (which 
** the MACRO form does).
*/
int sqlite3PutVarint(unsigned char*, u64);
int sqlite3PutVarint32(unsigned char*, u32);
u8 sqlite3GetVarint(const unsigned char *, u64 *);
u8 sqlite3GetVarint32(const unsigned char *, u32 *);
int sqlite3VarintLen(u64 v);

/*
** The header of a record consists of a sequence variable-length integers.
** These integers are almost always small and are encoded as a single byte.
** The following macros take advantage this fact to provide a fast encode
** and decode of the integers in a record header.  It is faster for the common
** case where the integer is a single byte.  It is a little slower when the
** integer is two or more bytes.  But overall it is faster.
**
** The following expressions are equivalent:
**
**     x = sqlite3GetVarint32( A, &B );
**     x = sqlite3PutVarint32( A, B );
**
**     x = getVarint32( A, B );
**     x = putVarint32( A, B );
**
*/
#define getVarint32(A,B)  \
  (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
#define putVarint32(A,B)  \
  (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
  sqlite3PutVarint32((A),(B)))
#define getVarint    sqlite3GetVarint
#define putVarint    sqlite3PutVarint


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

void sqlite3Error(sqlite3*, int, const char*,...);
void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
u8 sqlite3HexToInt(int h);
int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);

#if defined(SQLITE_TEST) 
const char *sqlite3ErrName(int);
#endif

# define SQLITE_INT_TO_PTR(X)  ((void*)(intptr_t)(X))
# define SQLITE_PTR_TO_INT(X)  ((int)(intptr_t)(X))
#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

/*
** A macro to hint to the compiler that a function should not be
** inlined.
*/
#if defined(__GNUC__)
#  define SQLITE_NOINLINE  __attribute__((noinline))
#elif defined(_MSC_VER)
#  define SQLITE_NOINLINE  __declspec(noinline)
#else
#  define SQLITE_NOINLINE
#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.
................................................................................
LogEst sqlite3LogEstFromDouble(double);
#endif
u64 sqlite3LogEstToInt(LogEst);

/*
** Routines to read and write variable-length integers.  These used to
** be defined locally, but now we use the varint routines in the util.c
** file.


*/
int sqlite3PutVarint(unsigned char*, u64);

u8 sqlite3GetVarint(const unsigned char *, u64 *);
u8 sqlite3GetVarint32(const unsigned char *, u32 *);
int sqlite3VarintLen(u64 v);

/*
** The common case is for a varint to be a single byte.  They following
** macros handle the common case without a procedure call, but then call
** the procedure for larger varints.












*/
#define getVarint32(A,B)  \
  (u8)((*(A)<(u8)0x80)?((B)=(u32)*(A)),1:sqlite3GetVarint32((A),(u32 *)&(B)))
#define putVarint32(A,B)  \
  (u8)(((u32)(B)<(u32)0x80)?(*(A)=(unsigned char)(B)),1:\
  sqlite3PutVarint((A),(B)))
#define getVarint    sqlite3GetVarint
#define putVarint    sqlite3PutVarint


const char *sqlite3IndexAffinityStr(Vdbe *, Index *);
void sqlite3TableAffinity(Vdbe*, Table*, int);
char sqlite3CompareAffinity(Expr *pExpr, char aff2);
int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity);
char sqlite3ExprAffinity(Expr *pExpr);
int sqlite3Atoi64(const char*, i64*, int, u8);
int sqlite3DecOrHexToI64(const char*, i64*);
void sqlite3ErrorWithMsg(sqlite3*, int, const char*,...);
void sqlite3Error(sqlite3*,int);
void *sqlite3HexToBlob(sqlite3*, const char *z, int n);
u8 sqlite3HexToInt(int h);
int sqlite3TwoPartName(Parse *, Token *, Token *, Token **);

#if defined(SQLITE_TEST) 
const char *sqlite3ErrName(int);
#endif

  /* Check that the trigger name is not reserved and that no trigger of the
  ** specified name exists */
  zName = sqlite3NameFromToken(db, pName);
  if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto trigger_cleanup;
  }
  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash),
                      zName, sqlite3Strlen30(zName)) ){
    if( !noErr ){
      sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
    }else{
      assert( !db->init.busy );
      sqlite3CodeVerifySchema(pParse, iDb);
    }
    goto trigger_cleanup;
................................................................................
        sqlite3MPrintf(db, "type='trigger' AND name='%q'", zName));
  }

  if( db->init.busy ){
    Trigger *pLink = pTrig;
    Hash *pHash = &db->aDb[iDb].pSchema->trigHash;
    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    pTrig = sqlite3HashInsert(pHash, zName, sqlite3Strlen30(zName), pTrig);
    if( pTrig ){
      db->mallocFailed = 1;
    }else if( pLink->pSchema==pLink->pTabSchema ){
      Table *pTab;
      int n = sqlite3Strlen30(pLink->table);
      pTab = sqlite3HashFind(&pLink->pTabSchema->tblHash, pLink->table, n);
      assert( pTab!=0 );
      pLink->pNext = pTab->pTrigger;
      pTab->pTrigger = pLink;
    }
  }

triggerfinish_cleanup:
................................................................................
** instead of the trigger name.
**/
void sqlite3DropTrigger(Parse *pParse, SrcList *pName, int noErr){
  Trigger *pTrigger = 0;
  int i;
  const char *zDb;
  const char *zName;
  int nName;
  sqlite3 *db = pParse->db;

  if( db->mallocFailed ) goto drop_trigger_cleanup;
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    goto drop_trigger_cleanup;
  }

  assert( pName->nSrc==1 );
  zDb = pName->a[0].zDatabase;
  zName = pName->a[0].zName;
  nName = sqlite3Strlen30(zName);
  assert( zDb!=0 || sqlite3BtreeHoldsAllMutexes(db) );
  for(i=OMIT_TEMPDB; i<db->nDb; i++){
    int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
    if( zDb && sqlite3StrICmp(db->aDb[j].zName, zDb) ) continue;
    assert( sqlite3SchemaMutexHeld(db, j, 0) );
    pTrigger = sqlite3HashFind(&(db->aDb[j].pSchema->trigHash), zName, nName);
    if( pTrigger ) break;
  }
  if( !pTrigger ){
    if( !noErr ){
      sqlite3ErrorMsg(pParse, "no such trigger: %S", pName, 0);
    }else{
      sqlite3CodeVerifyNamedSchema(pParse, zDb);
................................................................................
}

/*
** Return a pointer to the Table structure for the table that a trigger
** is set on.
*/
static Table *tableOfTrigger(Trigger *pTrigger){
  int n = sqlite3Strlen30(pTrigger->table);
  return sqlite3HashFind(&pTrigger->pTabSchema->tblHash, pTrigger->table, n);
}


/*
** Drop a trigger given a pointer to that trigger. 
*/
void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
................................................................................
*/
void sqlite3UnlinkAndDeleteTrigger(sqlite3 *db, int iDb, const char *zName){
  Trigger *pTrigger;
  Hash *pHash;

  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  pHash = &(db->aDb[iDb].pSchema->trigHash);
  pTrigger = sqlite3HashInsert(pHash, zName, sqlite3Strlen30(zName), 0);
  if( ALWAYS(pTrigger) ){
    if( pTrigger->pSchema==pTrigger->pTabSchema ){
      Table *pTab = tableOfTrigger(pTrigger);
      Trigger **pp;
      for(pp=&pTab->pTrigger; *pp!=pTrigger; pp=&((*pp)->pNext));
      *pp = (*pp)->pNext;
    }

  /* Check that the trigger name is not reserved and that no trigger of the
  ** specified name exists */
  zName = sqlite3NameFromToken(db, pName);
  if( !zName || SQLITE_OK!=sqlite3CheckObjectName(pParse, zName) ){
    goto trigger_cleanup;
  }
  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  if( sqlite3HashFind(&(db->aDb[iDb].pSchema->trigHash),zName) ){

    if( !noErr ){
      sqlite3ErrorMsg(pParse, "trigger %T already exists", pName);
    }else{
      assert( !db->init.busy );
      sqlite3CodeVerifySchema(pParse, iDb);
    }
    goto trigger_cleanup;
................................................................................
        sqlite3MPrintf(db, "type='trigger' AND name='%q'", zName));
  }

  if( db->init.busy ){
    Trigger *pLink = pTrig;
    Hash *pHash = &db->aDb[iDb].pSchema->trigHash;
    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    pTrig = sqlite3HashInsert(pHash, zName, pTrig);
    if( pTrig ){
      db->mallocFailed = 1;
    }else if( pLink->pSchema==pLink->pTabSchema ){
      Table *pTab;

      pTab = sqlite3HashFind(&pLink->pTabSchema->tblHash, pLink->table);
      assert( pTab!=0 );
      pLink->pNext = pTab->pTrigger;
      pTab->pTrigger = pLink;
    }
  }

triggerfinish_cleanup:
................................................................................
** instead of the trigger name.
**/
void sqlite3DropTrigger(Parse *pParse, SrcList *pName, int noErr){
  Trigger *pTrigger = 0;
  int i;
  const char *zDb;
  const char *zName;

  sqlite3 *db = pParse->db;

  if( db->mallocFailed ) goto drop_trigger_cleanup;
  if( SQLITE_OK!=sqlite3ReadSchema(pParse) ){
    goto drop_trigger_cleanup;
  }

  assert( pName->nSrc==1 );
  zDb = pName->a[0].zDatabase;
  zName = pName->a[0].zName;

  assert( zDb!=0 || sqlite3BtreeHoldsAllMutexes(db) );
  for(i=OMIT_TEMPDB; i<db->nDb; i++){
    int j = (i<2) ? i^1 : i;  /* Search TEMP before MAIN */
    if( zDb && sqlite3StrICmp(db->aDb[j].zName, zDb) ) continue;
    assert( sqlite3SchemaMutexHeld(db, j, 0) );
    pTrigger = sqlite3HashFind(&(db->aDb[j].pSchema->trigHash), zName);
    if( pTrigger ) break;
  }
  if( !pTrigger ){
    if( !noErr ){
      sqlite3ErrorMsg(pParse, "no such trigger: %S", pName, 0);
    }else{
      sqlite3CodeVerifyNamedSchema(pParse, zDb);
................................................................................
}

/*
** Return a pointer to the Table structure for the table that a trigger
** is set on.
*/
static Table *tableOfTrigger(Trigger *pTrigger){

  return sqlite3HashFind(&pTrigger->pTabSchema->tblHash, pTrigger->table);
}


/*
** Drop a trigger given a pointer to that trigger. 
*/
void sqlite3DropTriggerPtr(Parse *pParse, Trigger *pTrigger){
................................................................................
*/
void sqlite3UnlinkAndDeleteTrigger(sqlite3 *db, int iDb, const char *zName){
  Trigger *pTrigger;
  Hash *pHash;

  assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
  pHash = &(db->aDb[iDb].pSchema->trigHash);
  pTrigger = sqlite3HashInsert(pHash, zName, 0);
  if( ALWAYS(pTrigger) ){
    if( pTrigger->pSchema==pTrigger->pTabSchema ){
      Table *pTab = tableOfTrigger(pTrigger);
      Trigger **pp;
      for(pp=&pTab->pTrigger; *pp!=pTrigger; pp=&((*pp)->pNext));
      *pp = (*pp)->pNext;
    }

#ifndef SQLITE_OMIT_UTF16
/*
** This routine transforms the internal text encoding used by pMem to
** desiredEnc. It is an error if the string is already of the desired
** encoding, or if *pMem does not contain a string value.
*/
int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
  int len;                    /* Maximum length of output string in bytes */
  unsigned char *zOut;                  /* Output buffer */
  unsigned char *zIn;                   /* Input iterator */
  unsigned char *zTerm;                 /* End of input */
  unsigned char *z;                     /* Output iterator */
  unsigned int c;

#ifndef SQLITE_OMIT_UTF16
/*
** This routine transforms the internal text encoding used by pMem to
** desiredEnc. It is an error if the string is already of the desired
** encoding, or if *pMem does not contain a string value.
*/
SQLITE_NOINLINE int sqlite3VdbeMemTranslate(Mem *pMem, u8 desiredEnc){
  int len;                    /* Maximum length of output string in bytes */
  unsigned char *zOut;                  /* Output buffer */
  unsigned char *zIn;                   /* Input iterator */
  unsigned char *zTerm;                 /* End of input */
  unsigned char *z;                     /* Output iterator */
  unsigned int c;

*/
int sqlite3Strlen30(const char *z){
  const char *z2 = z;
  if( z==0 ) return 0;
  while( *z2 ){ z2++; }
  return 0x3fffffff & (int)(z2 - z);
}










/*
** Set the most recent error code and error string for the sqlite
** handle "db". The error code is set to "err_code".
**
** If it is not NULL, string zFormat specifies the format of the
** error string in the style of the printf functions: The following
................................................................................
** zFormat and any string tokens that follow it are assumed to be
** encoded in UTF-8.
**
** To clear the most recent error for sqlite handle "db", sqlite3Error
** should be called with err_code set to SQLITE_OK and zFormat set
** to NULL.
*/
void sqlite3Error(sqlite3 *db, int err_code, const char *zFormat, ...){
  assert( db!=0 );
  db->errCode = err_code;


  if( zFormat && (db->pErr || (db->pErr = sqlite3ValueNew(db))!=0) ){
    char *z;
    va_list ap;
    va_start(ap, zFormat);
    z = sqlite3VMPrintf(db, zFormat, ap);
    va_end(ap);
    sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);
  }else if( db->pErr ){
    sqlite3ValueSetNull(db->pErr);
  }
}

/*
** Add an error message to pParse->zErrMsg and increment pParse->nErr.
** The following formatting characters are allowed:
**
**      %s      Insert a string
**      %z      A string that should be freed after use
**      %d      Insert an integer
**      %T      Insert a token
**      %S      Insert the first element of a SrcList
**
** This function should be used to report any error that occurs whilst
** compiling an SQL statement (i.e. within sqlite3_prepare()). The
** last thing the sqlite3_prepare() function does is copy the error
** stored by this function into the database handle using sqlite3Error().
** Function sqlite3Error() should be used during statement execution
** (sqlite3_step() etc.).
*/
void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
  char *zMsg;
  va_list ap;
  sqlite3 *db = pParse->db;
  va_start(ap, zFormat);
  zMsg = sqlite3VMPrintf(db, zFormat, ap);
................................................................................
** of bytes written is returned.
**
** A variable-length integer consists of the lower 7 bits of each byte
** for all bytes that have the 8th bit set and one byte with the 8th
** bit clear.  Except, if we get to the 9th byte, it stores the full
** 8 bits and is the last byte.
*/
int sqlite3PutVarint(unsigned char *p, u64 v){
  int i, j, n;
  u8 buf[10];
  if( v & (((u64)0xff000000)<<32) ){
    p[8] = (u8)v;
    v >>= 8;
    for(i=7; i>=0; i--){
      p[i] = (u8)((v & 0x7f) | 0x80);
................................................................................
  buf[0] &= 0x7f;
  assert( n<=9 );
  for(i=0, j=n-1; j>=0; j--, i++){
    p[i] = buf[j];
  }
  return n;
}

/*
** This routine is a faster version of sqlite3PutVarint() that only
** works for 32-bit positive integers and which is optimized for
** the common case of small integers.  A MACRO version, putVarint32,
** is provided which inlines the single-byte case.  All code should use
** the MACRO version as this function assumes the single-byte case has
** already been handled.
*/
int sqlite3PutVarint32(unsigned char *p, u32 v){
#ifndef putVarint32
  if( (v & ~0x7f)==0 ){

    p[0] = v;
    return 1;
  }
#endif
  if( (v & ~0x3fff)==0 ){
    p[0] = (u8)((v>>7) | 0x80);


    p[1] = (u8)(v & 0x7f);
    return 2;
  }
  return sqlite3PutVarint(p, v);

}

/*
** Bitmasks used by sqlite3GetVarint().  These precomputed constants
** are defined here rather than simply putting the constant expressions
** inline in order to work around bugs in the RVT compiler.
**

*/
int sqlite3Strlen30(const char *z){
  const char *z2 = z;
  if( z==0 ) return 0;
  while( *z2 ){ z2++; }
  return 0x3fffffff & (int)(z2 - z);
}

/*
** Set the current error code to err_code and clear any prior error message.
*/
void sqlite3Error(sqlite3 *db, int err_code){
  assert( db!=0 );
  db->errCode = err_code;
  if( db->pErr ) sqlite3ValueSetNull(db->pErr);
}

/*
** Set the most recent error code and error string for the sqlite
** handle "db". The error code is set to "err_code".
**
** If it is not NULL, string zFormat specifies the format of the
** error string in the style of the printf functions: The following
................................................................................
** zFormat and any string tokens that follow it are assumed to be
** encoded in UTF-8.
**
** To clear the most recent error for sqlite handle "db", sqlite3Error
** should be called with err_code set to SQLITE_OK and zFormat set
** to NULL.
*/
void sqlite3ErrorWithMsg(sqlite3 *db, int err_code, const char *zFormat, ...){
  assert( db!=0 );
  db->errCode = err_code;
  if( zFormat==0 ){
    sqlite3Error(db, err_code);
  }else if( db->pErr || (db->pErr = sqlite3ValueNew(db))!=0 ){
    char *z;
    va_list ap;
    va_start(ap, zFormat);
    z = sqlite3VMPrintf(db, zFormat, ap);
    va_end(ap);
    sqlite3ValueSetStr(db->pErr, -1, z, SQLITE_UTF8, SQLITE_DYNAMIC);


  }
}

/*
** Add an error message to pParse->zErrMsg and increment pParse->nErr.
** The following formatting characters are allowed:
**
**      %s      Insert a string
**      %z      A string that should be freed after use
**      %d      Insert an integer
**      %T      Insert a token
**      %S      Insert the first element of a SrcList
**
** This function should be used to report any error that occurs while
** compiling an SQL statement (i.e. within sqlite3_prepare()). The
** last thing the sqlite3_prepare() function does is copy the error
** stored by this function into the database handle using sqlite3Error().
** Functions sqlite3Error() or sqlite3ErrorWithMsg() should be used
** during statement execution (sqlite3_step() etc.).
*/
void sqlite3ErrorMsg(Parse *pParse, const char *zFormat, ...){
  char *zMsg;
  va_list ap;
  sqlite3 *db = pParse->db;
  va_start(ap, zFormat);
  zMsg = sqlite3VMPrintf(db, zFormat, ap);
................................................................................
** of bytes written is returned.
**
** A variable-length integer consists of the lower 7 bits of each byte
** for all bytes that have the 8th bit set and one byte with the 8th
** bit clear.  Except, if we get to the 9th byte, it stores the full
** 8 bits and is the last byte.
*/
static int SQLITE_NOINLINE putVarint64(unsigned char *p, u64 v){
  int i, j, n;
  u8 buf[10];
  if( v & (((u64)0xff000000)<<32) ){
    p[8] = (u8)v;
    v >>= 8;
    for(i=7; i>=0; i--){
      p[i] = (u8)((v & 0x7f) | 0x80);
................................................................................
  buf[0] &= 0x7f;
  assert( n<=9 );
  for(i=0, j=n-1; j>=0; j--, i++){
    p[i] = buf[j];
  }
  return n;
}









int sqlite3PutVarint(unsigned char *p, u64 v){


  if( v<=0x7f ){
    p[0] = v&0x7f;
    return 1;
  }



  if( v<=0x3fff ){
    p[0] = ((v>>7)&0x7f)|0x80;
    p[1] = v&0x7f;
    return 2;
  }

  return putVarint64(p,v);
}

/*
** Bitmasks used by sqlite3GetVarint().  These precomputed constants
** are defined here rather than simply putting the constant expressions
** inline in order to work around bugs in the RVT compiler.
**

#endif

/*
** Convert the given register into a string if it isn't one
** already. Return non-zero if a malloc() fails.
*/
#define Stringify(P, enc) \
   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc)) \
     { goto no_mem; }

/*
** An ephemeral string value (signified by the MEM_Ephem flag) contains
** a pointer to a dynamically allocated string where some other entity
** is responsible for deallocating that string.  Because the register
** does not control the string, it might be deleted without the register
................................................................................
}

/*
** Try to convert a value into a numeric representation if we can
** do so without loss of information.  In other words, if the string
** looks like a number, convert it into a number.  If it does not
** look like a number, leave it alone.









*/
static void applyNumericAffinity(Mem *pRec){
  double rValue;
  i64 iValue;
  u8 enc = pRec->enc;
  if( (pRec->flags&MEM_Str)==0 ) return;
  if( sqlite3AtoF(pRec->z, &rValue, pRec->n, enc)==0 ) return;
  if( 0==sqlite3Atoi64(pRec->z, &iValue, pRec->n, enc) ){
    pRec->u.i = iValue;
    pRec->flags |= MEM_Int;
  }else{
    pRec->r = rValue;
    pRec->flags |= MEM_Real;

  }
}
#define ApplyNumericAffinity(X)  \
   if(((X)->flags&(MEM_Real|MEM_Int))==0){applyNumericAffinity(X);}

/*
** Processing is determine by the affinity parameter:
**
** SQLITE_AFF_INTEGER:
** SQLITE_AFF_REAL:
** SQLITE_AFF_NUMERIC:
................................................................................
){
  if( affinity==SQLITE_AFF_TEXT ){
    /* Only attempt the conversion to TEXT if there is an integer or real
    ** representation (blob and NULL do not get converted) but no string
    ** representation.
    */
    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
      sqlite3VdbeMemStringify(pRec, enc);
    }
    pRec->flags &= ~(MEM_Real|MEM_Int);
  }else if( affinity!=SQLITE_AFF_NONE ){
    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
             || affinity==SQLITE_AFF_NUMERIC );
    ApplyNumericAffinity(pRec);
    if( pRec->flags & MEM_Real ){


      sqlite3VdbeIntegerAffinity(pRec);

    }
  }
}

/*
** Try to convert the type of a function argument or a result column
** into a numeric representation.  Use either INTEGER or REAL whichever
................................................................................
** is appropriate.  But only do the conversion if it is possible without
** loss of information and return the revised type of the argument.
*/
int sqlite3_value_numeric_type(sqlite3_value *pVal){
  int eType = sqlite3_value_type(pVal);
  if( eType==SQLITE_TEXT ){
    Mem *pMem = (Mem*)pVal;
    applyNumericAffinity(pMem);
    eType = sqlite3_value_type(pVal);
  }
  return eType;
}

/*
** Exported version of applyAffinity(). This one works on sqlite3_value*, 
................................................................................
void sqlite3ValueApplyAffinity(
  sqlite3_value *pVal, 
  u8 affinity, 
  u8 enc
){
  applyAffinity((Mem *)pVal, affinity, enc);
}



















/*
** Return the numeric type for pMem, either MEM_Int or MEM_Real or both or
** none.  
**
** Unlike applyNumericAffinity(), this routine does not modify pMem->flags.
** But it does set pMem->r and pMem->u.i appropriately.
*/
static u16 numericType(Mem *pMem){
  if( pMem->flags & (MEM_Int|MEM_Real) ){
    return pMem->flags & (MEM_Int|MEM_Real);
  }
  if( pMem->flags & (MEM_Str|MEM_Blob) ){
    if( sqlite3AtoF(pMem->z, &pMem->r, pMem->n, pMem->enc)==0 ){
      return 0;
    }
    if( sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc)==SQLITE_OK ){
      return MEM_Int;
    }
    return MEM_Real;
  }
  return 0;
}

#ifdef SQLITE_DEBUG
/*
** Write a nice string representation of the contents of cell pMem
................................................................................
    */
    assert( pOp->opflags==sqlite3OpcodeProperty[pOp->opcode] );
    if( pOp->opflags & OPFLG_OUT2_PRERELEASE ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=(p->nMem-p->nCursor) );
      pOut = &aMem[pOp->p2];
      memAboutToChange(p, pOut);
      VdbeMemRelease(pOut);
      pOut->flags = MEM_Int;
    }

    /* Sanity checking on other operands */
#ifdef SQLITE_DEBUG
    if( (pOp->opflags & OPFLG_IN1)!=0 ){
      assert( pOp->p1>0 );
................................................................................
  u16 nullFlag;
  cnt = pOp->p3-pOp->p2;
  assert( pOp->p3<=(p->nMem-p->nCursor) );
  pOut->flags = nullFlag = pOp->p1 ? (MEM_Null|MEM_Cleared) : MEM_Null;
  while( cnt>0 ){
    pOut++;
    memAboutToChange(p, pOut);
    VdbeMemRelease(pOut);
    pOut->flags = nullFlag;
    cnt--;
  }
  break;
}

/* Opcode: SoftNull P1 * * * *
................................................................................
  pIn1 = &aMem[p1];
  pOut = &aMem[p2];
  do{
    assert( pOut<=&aMem[(p->nMem-p->nCursor)] );
    assert( pIn1<=&aMem[(p->nMem-p->nCursor)] );
    assert( memIsValid(pIn1) );
    memAboutToChange(p, pOut);
    VdbeMemRelease(pOut);
    zMalloc = pOut->zMalloc;
    memcpy(pOut, pIn1, sizeof(Mem));
#ifdef SQLITE_DEBUG
    if( pOut->pScopyFrom>=&aMem[p1] && pOut->pScopyFrom<&aMem[p1+pOp->p3] ){
      pOut->pScopyFrom += p1 - pOp->p2;
    }
#endif
................................................................................
    sqlite3VdbeMemRealify(pIn1);
  }
  break;
}
#endif

#ifndef SQLITE_OMIT_CAST
/* Opcode: ToText P1 * * * *
**
** Force the value in register P1 to be text.
** If the value is numeric, convert it to a string using the
** equivalent of sprintf().  Blob values are unchanged and
** are afterwards simply interpreted as text.





**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToText: {                  /* same as TK_TO_TEXT, in1 */






  pIn1 = &aMem[pOp->p1];
  memAboutToChange(p, pIn1);
  if( pIn1->flags & MEM_Null ) break;
  assert( MEM_Str==(MEM_Blob>>3) );
  pIn1->flags |= (pIn1->flags&MEM_Blob)>>3;
  applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
  rc = ExpandBlob(pIn1);
  assert( pIn1->flags & MEM_Str || db->mallocFailed );
  pIn1->flags &= ~(MEM_Int|MEM_Real|MEM_Blob|MEM_Zero);
  UPDATE_MAX_BLOBSIZE(pIn1);
  break;
}

/* Opcode: ToBlob P1 * * * *
**
** Force the value in register P1 to be a BLOB.
** If the value is numeric, convert it to a string first.
** Strings are simply reinterpreted as blobs with no change
** to the underlying data.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToBlob: {                  /* same as TK_TO_BLOB, in1 */
  pIn1 = &aMem[pOp->p1];
  if( pIn1->flags & MEM_Null ) break;
  if( (pIn1->flags & MEM_Blob)==0 ){
    applyAffinity(pIn1, SQLITE_AFF_TEXT, encoding);
    assert( pIn1->flags & MEM_Str || db->mallocFailed );
    MemSetTypeFlag(pIn1, MEM_Blob);
  }else{
    pIn1->flags &= ~(MEM_TypeMask&~MEM_Blob);
  }
  UPDATE_MAX_BLOBSIZE(pIn1);
  break;
}

/* Opcode: ToNumeric P1 * * * *
**
** Force the value in register P1 to be numeric (either an
** integer or a floating-point number.)
** If the value is text or blob, try to convert it to an using the
** equivalent of atoi() or atof() and store 0 if no such conversion 
** is possible.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToNumeric: {                  /* same as TK_TO_NUMERIC, in1 */
  pIn1 = &aMem[pOp->p1];
  sqlite3VdbeMemNumerify(pIn1);
  break;
}
#endif /* SQLITE_OMIT_CAST */

/* Opcode: ToInt P1 * * * *
**
** Force the value in register P1 to be an integer.  If
** The value is currently a real number, drop its fractional part.
** If the value is text or blob, try to convert it to an integer using the
** equivalent of atoi() and store 0 if no such conversion is possible.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToInt: {                  /* same as TK_TO_INT, in1 */
  pIn1 = &aMem[pOp->p1];
  if( (pIn1->flags & MEM_Null)==0 ){
    sqlite3VdbeMemIntegerify(pIn1);
  }
  break;
}

#if !defined(SQLITE_OMIT_CAST) && !defined(SQLITE_OMIT_FLOATING_POINT)
/* Opcode: ToReal P1 * * * *
**
** Force the value in register P1 to be a floating point number.
** If The value is currently an integer, convert it.
** If the value is text or blob, try to convert it to an integer using the
** equivalent of atoi() and store 0.0 if no such conversion is possible.
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_ToReal: {                  /* same as TK_TO_REAL, in1 */
  pIn1 = &aMem[pOp->p1];
  memAboutToChange(p, pIn1);
  if( (pIn1->flags & MEM_Null)==0 ){
    sqlite3VdbeMemRealify(pIn1);
  }
  break;
}
#endif /* !defined(SQLITE_OMIT_CAST) && !defined(SQLITE_OMIT_FLOATING_POINT) */

/* Opcode: Lt P1 P2 P3 P4 P5
** Synopsis: if r[P1]<r[P3] goto P2
**
** Compare the values in register P1 and P3.  If reg(P3)<reg(P1) then
** jump to address P2.  
**
** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
................................................................................
  */
  assert( p2<pC->nHdrParsed );
  assert( rc==SQLITE_OK );
  assert( sqlite3VdbeCheckMemInvariants(pDest) );
  if( pC->szRow>=aOffset[p2+1] ){
    /* This is the common case where the desired content fits on the original
    ** page - where the content is not on an overflow page */
    VdbeMemRelease(pDest);
    sqlite3VdbeSerialGet(pC->aRow+aOffset[p2], aType[p2], pDest);
  }else{
    /* This branch happens only when content is on overflow pages */
    t = aType[p2];
    if( ((pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0
          && ((t>=12 && (t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0))
     || (len = sqlite3VdbeSerialTypeLen(t))==0
................................................................................
  pC->seekOp = pOp->opcode;
#endif
  if( pC->isTable ){
    /* The input value in P3 might be of any type: integer, real, string,
    ** blob, or NULL.  But it needs to be an integer before we can do
    ** the seek, so covert it. */
    pIn3 = &aMem[pOp->p3];

    ApplyNumericAffinity(pIn3);

    iKey = sqlite3VdbeIntValue(pIn3);
    pC->rowidIsValid = 0;

    /* If the P3 value could not be converted into an integer without
    ** loss of information, then special processing is required... */
    if( (pIn3->flags & MEM_Int)==0 ){
      if( (pIn3->flags & MEM_Real)==0 ){

#endif

/*
** Convert the given register into a string if it isn't one
** already. Return non-zero if a malloc() fails.
*/
#define Stringify(P, enc) \
   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc,0)) \
     { goto no_mem; }

/*
** An ephemeral string value (signified by the MEM_Ephem flag) contains
** a pointer to a dynamically allocated string where some other entity
** is responsible for deallocating that string.  Because the register
** does not control the string, it might be deleted without the register
................................................................................
}

/*
** Try to convert a value into a numeric representation if we can
** do so without loss of information.  In other words, if the string
** looks like a number, convert it into a number.  If it does not
** look like a number, leave it alone.
**
** If the bTryForInt flag is true, then extra effort is made to give
** an integer representation.  Strings that look like floating point
** values but which have no fractional component (example: '48.00')
** will have a MEM_Int representation when bTryForInt is true.
**
** If bTryForInt is false, then if the input string contains a decimal
** point or exponential notation, the result is only MEM_Real, even
** if there is an exact integer representation of the quantity.
*/
static void applyNumericAffinity(Mem *pRec, int bTryForInt){
  double rValue;
  i64 iValue;
  u8 enc = pRec->enc;
  if( (pRec->flags&MEM_Str)==0 ) return;
  if( sqlite3AtoF(pRec->z, &rValue, pRec->n, enc)==0 ) return;
  if( 0==sqlite3Atoi64(pRec->z, &iValue, pRec->n, enc) ){
    pRec->u.i = iValue;
    pRec->flags |= MEM_Int;
  }else{
    pRec->r = rValue;
    pRec->flags |= MEM_Real;
    if( bTryForInt ) sqlite3VdbeIntegerAffinity(pRec);
  }
}



/*
** Processing is determine by the affinity parameter:
**
** SQLITE_AFF_INTEGER:
** SQLITE_AFF_REAL:
** SQLITE_AFF_NUMERIC:
................................................................................
){
  if( affinity==SQLITE_AFF_TEXT ){
    /* Only attempt the conversion to TEXT if there is an integer or real
    ** representation (blob and NULL do not get converted) but no string
    ** representation.
    */
    if( 0==(pRec->flags&MEM_Str) && (pRec->flags&(MEM_Real|MEM_Int)) ){
      sqlite3VdbeMemStringify(pRec, enc, 1);
    }

  }else if( affinity!=SQLITE_AFF_NONE ){
    assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
             || affinity==SQLITE_AFF_NUMERIC );
    if( (pRec->flags & MEM_Int)==0 ){
      if( (pRec->flags & MEM_Real)==0 ){
        applyNumericAffinity(pRec,1);
      }else{
        sqlite3VdbeIntegerAffinity(pRec);
      }
    }
  }
}

/*
** Try to convert the type of a function argument or a result column
** into a numeric representation.  Use either INTEGER or REAL whichever
................................................................................
** is appropriate.  But only do the conversion if it is possible without
** loss of information and return the revised type of the argument.
*/
int sqlite3_value_numeric_type(sqlite3_value *pVal){
  int eType = sqlite3_value_type(pVal);
  if( eType==SQLITE_TEXT ){
    Mem *pMem = (Mem*)pVal;
    applyNumericAffinity(pMem, 0);
    eType = sqlite3_value_type(pVal);
  }
  return eType;
}

/*
** Exported version of applyAffinity(). This one works on sqlite3_value*, 
................................................................................
void sqlite3ValueApplyAffinity(
  sqlite3_value *pVal, 
  u8 affinity, 
  u8 enc
){
  applyAffinity((Mem *)pVal, affinity, enc);
}

/*
** pMem currently only holds a string type (or maybe a BLOB that we can
** interpret as a string if we want to).  Compute its corresponding
** numeric type, if has one.  Set the pMem->r and pMem->u.i fields
** accordingly.
*/
static u16 SQLITE_NOINLINE computeNumericType(Mem *pMem){
  assert( (pMem->flags & (MEM_Int|MEM_Real))==0 );
  assert( (pMem->flags & (MEM_Str|MEM_Blob))!=0 );
  if( sqlite3AtoF(pMem->z, &pMem->r, pMem->n, pMem->enc)==0 ){
    return 0;
  }
  if( sqlite3Atoi64(pMem->z, &pMem->u.i, pMem->n, pMem->enc)==SQLITE_OK ){
    return MEM_Int;
  }
  return MEM_Real;
}

/*
** Return the numeric type for pMem, either MEM_Int or MEM_Real or both or
** none.  
**
** Unlike applyNumericAffinity(), this routine does not modify pMem->flags.
** But it does set pMem->r and pMem->u.i appropriately.
*/
static u16 numericType(Mem *pMem){
  if( pMem->flags & (MEM_Int|MEM_Real) ){
    return pMem->flags & (MEM_Int|MEM_Real);
  }
  if( pMem->flags & (MEM_Str|MEM_Blob) ){
    return computeNumericType(pMem);






  }
  return 0;
}

#ifdef SQLITE_DEBUG
/*
** Write a nice string representation of the contents of cell pMem
................................................................................
    */
    assert( pOp->opflags==sqlite3OpcodeProperty[pOp->opcode] );
    if( pOp->opflags & OPFLG_OUT2_PRERELEASE ){
      assert( pOp->p2>0 );
      assert( pOp->p2<=(p->nMem-p->nCursor) );
      pOut = &aMem[pOp->p2];
      memAboutToChange(p, pOut);
      VdbeMemReleaseExtern(pOut);
      pOut->flags = MEM_Int;
    }

    /* Sanity checking on other operands */
#ifdef SQLITE_DEBUG
    if( (pOp->opflags & OPFLG_IN1)!=0 ){
      assert( pOp->p1>0 );
................................................................................
  u16 nullFlag;
  cnt = pOp->p3-pOp->p2;
  assert( pOp->p3<=(p->nMem-p->nCursor) );
  pOut->flags = nullFlag = pOp->p1 ? (MEM_Null|MEM_Cleared) : MEM_Null;
  while( cnt>0 ){
    pOut++;
    memAboutToChange(p, pOut);
    VdbeMemReleaseExtern(pOut);
    pOut->flags = nullFlag;
    cnt--;
  }
  break;
}

/* Opcode: SoftNull P1 * * * *
................................................................................
  pIn1 = &aMem[p1];
  pOut = &aMem[p2];
  do{
    assert( pOut<=&aMem[(p->nMem-p->nCursor)] );
    assert( pIn1<=&aMem[(p->nMem-p->nCursor)] );
    assert( memIsValid(pIn1) );
    memAboutToChange(p, pOut);
    VdbeMemReleaseExtern(pOut);
    zMalloc = pOut->zMalloc;
    memcpy(pOut, pIn1, sizeof(Mem));
#ifdef SQLITE_DEBUG
    if( pOut->pScopyFrom>=&aMem[p1] && pOut->pScopyFrom<&aMem[p1+pOp->p3] ){
      pOut->pScopyFrom += p1 - pOp->p2;
    }
#endif
................................................................................
    sqlite3VdbeMemRealify(pIn1);
  }
  break;
}
#endif

#ifndef SQLITE_OMIT_CAST
/* Opcode: Cast P1 P2 * * *
**
** Force the value in register P1 to be the type defined by P2.
** 
** <ul>
** <li value="97"> TEXT
** <li value="98"> BLOB
** <li value="99"> NUMERIC
** <li value="100"> INTEGER
** <li value="101"> REAL
** </ul>
**
** A NULL value is not changed by this routine.  It remains NULL.
*/
case OP_Cast: {                  /* in1 */
  assert( pOp->p2>=SQLITE_AFF_TEXT && pOp->p2<=SQLITE_AFF_REAL );
  testcase( pOp->p2==SQLITE_AFF_TEXT );
  testcase( pOp->p2==SQLITE_AFF_NONE );
  testcase( pOp->p2==SQLITE_AFF_NUMERIC );
  testcase( pOp->p2==SQLITE_AFF_INTEGER );
  testcase( pOp->p2==SQLITE_AFF_REAL );
  pIn1 = &aMem[pOp->p1];
  memAboutToChange(p, pIn1);




  rc = ExpandBlob(pIn1);


  sqlite3VdbeMemCast(pIn1, pOp->p2, encoding);






















  UPDATE_MAX_BLOBSIZE(pIn1);
  break;
}
















#endif /* SQLITE_OMIT_CAST */






































/* Opcode: Lt P1 P2 P3 P4 P5
** Synopsis: if r[P1]<r[P3] goto P2
**
** Compare the values in register P1 and P3.  If reg(P3)<reg(P1) then
** jump to address P2.  
**
** If the SQLITE_JUMPIFNULL bit of P5 is set and either reg(P1) or
................................................................................
  */
  assert( p2<pC->nHdrParsed );
  assert( rc==SQLITE_OK );
  assert( sqlite3VdbeCheckMemInvariants(pDest) );
  if( pC->szRow>=aOffset[p2+1] ){
    /* This is the common case where the desired content fits on the original
    ** page - where the content is not on an overflow page */
    VdbeMemReleaseExtern(pDest);
    sqlite3VdbeSerialGet(pC->aRow+aOffset[p2], aType[p2], pDest);
  }else{
    /* This branch happens only when content is on overflow pages */
    t = aType[p2];
    if( ((pOp->p5 & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG))!=0
          && ((t>=12 && (t&1)==0) || (pOp->p5 & OPFLAG_TYPEOFARG)!=0))
     || (len = sqlite3VdbeSerialTypeLen(t))==0
................................................................................
  pC->seekOp = pOp->opcode;
#endif
  if( pC->isTable ){
    /* The input value in P3 might be of any type: integer, real, string,
    ** blob, or NULL.  But it needs to be an integer before we can do
    ** the seek, so covert it. */
    pIn3 = &aMem[pOp->p3];
    if( (pIn3->flags & (MEM_Int|MEM_Real))==0 ){
      applyNumericAffinity(pIn3, 0);
    }
    iKey = sqlite3VdbeIntValue(pIn3);
    pC->rowidIsValid = 0;

    /* If the P3 value could not be converted into an integer without
    ** loss of information, then special processing is required... */
    if( (pIn3->flags & MEM_Int)==0 ){
      if( (pIn3->flags & MEM_Real)==0 ){

#else
  void sqlite3VdbeMemSetDouble(Mem*, double);
#endif
void sqlite3VdbeMemSetNull(Mem*);
void sqlite3VdbeMemSetZeroBlob(Mem*,int);
void sqlite3VdbeMemSetRowSet(Mem*);
int sqlite3VdbeMemMakeWriteable(Mem*);
int sqlite3VdbeMemStringify(Mem*, int);
i64 sqlite3VdbeIntValue(Mem*);
int sqlite3VdbeMemIntegerify(Mem*);
double sqlite3VdbeRealValue(Mem*);
void sqlite3VdbeIntegerAffinity(Mem*);
int sqlite3VdbeMemRealify(Mem*);
int sqlite3VdbeMemNumerify(Mem*);

int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,int,Mem*);
void sqlite3VdbeMemRelease(Mem *p);
void sqlite3VdbeMemReleaseExternal(Mem *p);
#define VdbeMemDynamic(X)  \
  (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)
#define VdbeMemRelease(X)  \
  if( VdbeMemDynamic(X) ) sqlite3VdbeMemReleaseExternal(X);
int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
const char *sqlite3OpcodeName(int);
int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
int sqlite3VdbeCloseStatement(Vdbe *, int);
void sqlite3VdbeFrameDelete(VdbeFrame*);
int sqlite3VdbeFrameRestore(VdbeFrame *);

#else
  void sqlite3VdbeMemSetDouble(Mem*, double);
#endif
void sqlite3VdbeMemSetNull(Mem*);
void sqlite3VdbeMemSetZeroBlob(Mem*,int);
void sqlite3VdbeMemSetRowSet(Mem*);
int sqlite3VdbeMemMakeWriteable(Mem*);
int sqlite3VdbeMemStringify(Mem*, u8, u8);
i64 sqlite3VdbeIntValue(Mem*);
int sqlite3VdbeMemIntegerify(Mem*);
double sqlite3VdbeRealValue(Mem*);
void sqlite3VdbeIntegerAffinity(Mem*);
int sqlite3VdbeMemRealify(Mem*);
int sqlite3VdbeMemNumerify(Mem*);
void sqlite3VdbeMemCast(Mem*,u8,u8);
int sqlite3VdbeMemFromBtree(BtCursor*,u32,u32,int,Mem*);
void sqlite3VdbeMemRelease(Mem *p);
void sqlite3VdbeMemReleaseExternal(Mem *p);
#define VdbeMemDynamic(X)  \
  (((X)->flags&(MEM_Agg|MEM_Dyn|MEM_RowSet|MEM_Frame))!=0)
#define VdbeMemReleaseExtern(X)  \
  if( VdbeMemDynamic(X) ) sqlite3VdbeMemReleaseExternal(X);
int sqlite3VdbeMemFinalize(Mem*, FuncDef*);
const char *sqlite3OpcodeName(int);
int sqlite3VdbeMemGrow(Mem *pMem, int n, int preserve);
int sqlite3VdbeCloseStatement(Vdbe *, int);
void sqlite3VdbeFrameDelete(VdbeFrame*);
int sqlite3VdbeFrameRestore(VdbeFrame *);

  char *zErr;
  UNUSED_PARAMETER2(NotUsed, NotUsed2);
  zErr = sqlite3_mprintf(
      "unable to use function %s in the requested context", zName);
  sqlite3_result_error(context, zErr, -1);
  sqlite3_free(zErr);
}























/*
** Allocate or return the aggregate context for a user function.  A new
** context is allocated on the first call.  Subsequent calls return the
** same context that was returned on prior calls.
*/
void *sqlite3_aggregate_context(sqlite3_context *p, int nByte){
  Mem *pMem;
  assert( p && p->pFunc && p->pFunc->xStep );
  assert( sqlite3_mutex_held(p->s.db->mutex) );
  pMem = p->pMem;
  testcase( nByte<0 );
  if( (pMem->flags & MEM_Agg)==0 ){
    if( nByte<=0 ){
      sqlite3VdbeMemReleaseExternal(pMem);
      pMem->flags = MEM_Null;
      pMem->z = 0;

    }else{
      sqlite3VdbeMemGrow(pMem, nByte, 0);
      pMem->flags = MEM_Agg;
      pMem->u.pDef = p->pFunc;
      if( pMem->z ){
        memset(pMem->z, 0, nByte);
      }
    }
  }
  return (void*)pMem->z;
}

/*
** Return the auxilary data pointer, if any, for the iArg'th argument to
** the user-function defined by pCtx.
*/
void *sqlite3_get_auxdata(sqlite3_context *pCtx, int iArg){
................................................................................
  pVm = (Vdbe *)pStmt;
  if( pVm && pVm->pResultSet!=0 && i<pVm->nResColumn && i>=0 ){
    sqlite3_mutex_enter(pVm->db->mutex);
    pOut = &pVm->pResultSet[i];
  }else{
    if( pVm && ALWAYS(pVm->db) ){
      sqlite3_mutex_enter(pVm->db->mutex);
      sqlite3Error(pVm->db, SQLITE_RANGE, 0);
    }
    pOut = (Mem*)columnNullValue();
  }
  return pOut;
}

/*
................................................................................
static int vdbeUnbind(Vdbe *p, int i){
  Mem *pVar;
  if( vdbeSafetyNotNull(p) ){
    return SQLITE_MISUSE_BKPT;
  }
  sqlite3_mutex_enter(p->db->mutex);
  if( p->magic!=VDBE_MAGIC_RUN || p->pc>=0 ){
    sqlite3Error(p->db, SQLITE_MISUSE, 0);
    sqlite3_mutex_leave(p->db->mutex);
    sqlite3_log(SQLITE_MISUSE, 
        "bind on a busy prepared statement: [%s]", p->zSql);
    return SQLITE_MISUSE_BKPT;
  }
  if( i<1 || i>p->nVar ){
    sqlite3Error(p->db, SQLITE_RANGE, 0);
    sqlite3_mutex_leave(p->db->mutex);
    return SQLITE_RANGE;
  }
  i--;
  pVar = &p->aVar[i];
  sqlite3VdbeMemRelease(pVar);
  pVar->flags = MEM_Null;
  sqlite3Error(p->db, SQLITE_OK, 0);

  /* If the bit corresponding to this variable in Vdbe.expmask is set, then 
  ** binding a new value to this variable invalidates the current query plan.
  **
  ** IMPLEMENTATION-OF: R-48440-37595 If the specific value bound to host
  ** parameter in the WHERE clause might influence the choice of query plan
  ** for a statement, then the statement will be automatically recompiled,
................................................................................
  if( rc==SQLITE_OK ){
    if( zData!=0 ){
      pVar = &p->aVar[i-1];
      rc = sqlite3VdbeMemSetStr(pVar, zData, nData, encoding, xDel);
      if( rc==SQLITE_OK && encoding!=0 ){
        rc = sqlite3VdbeChangeEncoding(pVar, ENC(p->db));
      }
      sqlite3Error(p->db, rc, 0);
      rc = sqlite3ApiExit(p->db, rc);
    }
    sqlite3_mutex_leave(p->db->mutex);
  }else if( xDel!=SQLITE_STATIC && xDel!=SQLITE_TRANSIENT ){
    xDel((void*)zData);
  }
  return rc;
................................................................................
    *ppValue = &p->pUnpacked->aMem[iIdx];
    if( iIdx==p->iPKey ){
      sqlite3VdbeMemSetInt64(*ppValue, p->iKey1);
    }
  }

 preupdate_old_out:
  sqlite3Error(db, rc, 0);
  return sqlite3ApiExit(db, rc);
}
#endif /* SQLITE_ENABLE_PREUPDATE_HOOK */

#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
/*
** This function is called from within a pre-update callback to retrieve
................................................................................
        if( rc!=SQLITE_OK ) goto preupdate_new_out;
      }
    }
  }
  *ppValue = pMem;

 preupdate_new_out:
  sqlite3Error(db, rc, 0);
  return sqlite3ApiExit(db, rc);
}
#endif /* SQLITE_ENABLE_PREUPDATE_HOOK */

  char *zErr;
  UNUSED_PARAMETER2(NotUsed, NotUsed2);
  zErr = sqlite3_mprintf(
      "unable to use function %s in the requested context", zName);
  sqlite3_result_error(context, zErr, -1);
  sqlite3_free(zErr);
}

/*
** Create a new aggregate context for p and return a pointer to
** its pMem->z element.
*/
static SQLITE_NOINLINE void *createAggContext(sqlite3_context *p, int nByte){
  Mem *pMem = p->pMem;
  assert( (pMem->flags & MEM_Agg)==0 );
  if( nByte<=0 ){
    sqlite3VdbeMemReleaseExternal(pMem);
    pMem->flags = MEM_Null;
    pMem->z = 0;
  }else{
    sqlite3VdbeMemGrow(pMem, nByte, 0);
    pMem->flags = MEM_Agg;
    pMem->u.pDef = p->pFunc;
    if( pMem->z ){
      memset(pMem->z, 0, nByte);
    }
  }
  return (void*)pMem->z;
}

/*
** Allocate or return the aggregate context for a user function.  A new
** context is allocated on the first call.  Subsequent calls return the
** same context that was returned on prior calls.
*/
void *sqlite3_aggregate_context(sqlite3_context *p, int nByte){

  assert( p && p->pFunc && p->pFunc->xStep );
  assert( sqlite3_mutex_held(p->s.db->mutex) );

  testcase( nByte<0 );
  if( (p->pMem->flags & MEM_Agg)==0 ){




    return createAggContext(p, nByte);
  }else{



    return (void*)p->pMem->z;

  }



}

/*
** Return the auxilary data pointer, if any, for the iArg'th argument to
** the user-function defined by pCtx.
*/
void *sqlite3_get_auxdata(sqlite3_context *pCtx, int iArg){
................................................................................
  pVm = (Vdbe *)pStmt;
  if( pVm && pVm->pResultSet!=0 && i<pVm->nResColumn && i>=0 ){
    sqlite3_mutex_enter(pVm->db->mutex);
    pOut = &pVm->pResultSet[i];
  }else{
    if( pVm && ALWAYS(pVm->db) ){
      sqlite3_mutex_enter(pVm->db->mutex);
      sqlite3Error(pVm->db, SQLITE_RANGE);
    }
    pOut = (Mem*)columnNullValue();
  }
  return pOut;
}

/*
................................................................................
static int vdbeUnbind(Vdbe *p, int i){
  Mem *pVar;
  if( vdbeSafetyNotNull(p) ){
    return SQLITE_MISUSE_BKPT;
  }
  sqlite3_mutex_enter(p->db->mutex);
  if( p->magic!=VDBE_MAGIC_RUN || p->pc>=0 ){
    sqlite3Error(p->db, SQLITE_MISUSE);
    sqlite3_mutex_leave(p->db->mutex);
    sqlite3_log(SQLITE_MISUSE, 
        "bind on a busy prepared statement: [%s]", p->zSql);
    return SQLITE_MISUSE_BKPT;
  }
  if( i<1 || i>p->nVar ){
    sqlite3Error(p->db, SQLITE_RANGE);
    sqlite3_mutex_leave(p->db->mutex);
    return SQLITE_RANGE;
  }
  i--;
  pVar = &p->aVar[i];
  sqlite3VdbeMemRelease(pVar);
  pVar->flags = MEM_Null;
  sqlite3Error(p->db, SQLITE_OK);

  /* If the bit corresponding to this variable in Vdbe.expmask is set, then 
  ** binding a new value to this variable invalidates the current query plan.
  **
  ** IMPLEMENTATION-OF: R-48440-37595 If the specific value bound to host
  ** parameter in the WHERE clause might influence the choice of query plan
  ** for a statement, then the statement will be automatically recompiled,
................................................................................
  if( rc==SQLITE_OK ){
    if( zData!=0 ){
      pVar = &p->aVar[i-1];
      rc = sqlite3VdbeMemSetStr(pVar, zData, nData, encoding, xDel);
      if( rc==SQLITE_OK && encoding!=0 ){
        rc = sqlite3VdbeChangeEncoding(pVar, ENC(p->db));
      }
      sqlite3Error(p->db, rc);
      rc = sqlite3ApiExit(p->db, rc);
    }
    sqlite3_mutex_leave(p->db->mutex);
  }else if( xDel!=SQLITE_STATIC && xDel!=SQLITE_TRANSIENT ){
    xDel((void*)zData);
  }
  return rc;
................................................................................
    *ppValue = &p->pUnpacked->aMem[iIdx];
    if( iIdx==p->iPKey ){
      sqlite3VdbeMemSetInt64(*ppValue, p->iKey1);
    }
  }

 preupdate_old_out:
  sqlite3Error(db, rc);
  return sqlite3ApiExit(db, rc);
}
#endif /* SQLITE_ENABLE_PREUPDATE_HOOK */

#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
/*
** This function is called from within a pre-update callback to retrieve
................................................................................
        if( rc!=SQLITE_OK ) goto preupdate_new_out;
      }
    }
  }
  *ppValue = pMem;

 preupdate_new_out:
  sqlite3Error(db, rc);
  return sqlite3ApiExit(db, rc);
}
#endif /* SQLITE_ENABLE_PREUPDATE_HOOK */

    sqlite3BeginBenignMalloc();
    if( db->pErr==0 ) db->pErr = sqlite3ValueNew(db);
    sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT);
    sqlite3EndBenignMalloc();
    db->mallocFailed = mallocFailed;
    db->errCode = rc;
  }else{
    sqlite3Error(db, rc, 0);
  }
  return rc;
}

#ifdef SQLITE_ENABLE_SQLLOG
/*
** If an SQLITE_CONFIG_SQLLOG hook is registered and the VM has been run, 
................................................................................
    p->zErrMsg = 0;
    if( p->runOnlyOnce ) p->expired = 1;
  }else if( p->rc && p->expired ){
    /* The expired flag was set on the VDBE before the first call
    ** to sqlite3_step(). For consistency (since sqlite3_step() was
    ** called), set the database error in this case as well.
    */
    sqlite3Error(db, p->rc, p->zErrMsg ? "%s" : 0, p->zErrMsg);
    sqlite3DbFree(db, p->zErrMsg);
    p->zErrMsg = 0;
  }

  /* Reclaim all memory used by the VDBE
  */
  Cleanup(p);
................................................................................
  if( p->pNext ){
    p->pNext->pPrev = p->pPrev;
  }
  p->magic = VDBE_MAGIC_DEAD;
  p->db = 0;
  sqlite3DbFree(db, p);
}











































/*
** Make sure the cursor p is ready to read or write the row to which it
** was last positioned.  Return an error code if an OOM fault or I/O error
** prevents us from positioning the cursor to its correct position.
**
** If a MoveTo operation is pending on the given cursor, then do that
................................................................................
** a NULL row.
**
** If the cursor is already pointing to the correct row and that row has
** not been deleted out from under the cursor, then this routine is a no-op.
*/
int sqlite3VdbeCursorMoveto(VdbeCursor *p){
  if( p->deferredMoveto ){
    int res, rc;
#ifdef SQLITE_TEST
    extern int sqlite3_search_count;
#endif
    assert( p->isTable );
    rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
    if( rc ) return rc;
    p->lastRowid = p->movetoTarget;
    if( res!=0 ) return SQLITE_CORRUPT_BKPT;
    p->rowidIsValid = 1;
#ifdef SQLITE_TEST
    sqlite3_search_count++;
#endif
    p->deferredMoveto = 0;
    p->cacheStatus = CACHE_STALE;
  }else if( p->pCursor ){
    int hasMoved;
    int rc = sqlite3BtreeCursorHasMoved(p->pCursor, &hasMoved);
    if( rc ) return rc;
    if( hasMoved ){
      p->cacheStatus = CACHE_STALE;
      if( hasMoved==2 ) p->nullRow = 1;
    }


  }
  return SQLITE_OK;
}

/*
** The following functions:
**
................................................................................
      assert( sizeof(v)==sizeof(pMem->r) );
      memcpy(&v, &pMem->r, sizeof(v));
      swapMixedEndianFloat(v);
    }else{
      v = pMem->u.i;
    }
    len = i = sqlite3VdbeSerialTypeLen(serial_type);
    while( i-- ){

      buf[i] = (u8)(v&0xFF);
      v >>= 8;
    }

    return len;
  }

  /* String or blob */
  if( serial_type>=12 ){
    assert( pMem->n + ((pMem->flags & MEM_Zero)?pMem->u.nZero:0)
             == (int)sqlite3VdbeSerialTypeLen(serial_type) );
................................................................................
/* Input "x" is a sequence of unsigned characters that represent a
** big-endian integer.  Return the equivalent native integer
*/
#define ONE_BYTE_INT(x)    ((i8)(x)[0])
#define TWO_BYTE_INT(x)    (256*(i8)((x)[0])|(x)[1])
#define THREE_BYTE_INT(x)  (65536*(i8)((x)[0])|((x)[1]<<8)|(x)[2])
#define FOUR_BYTE_UINT(x)  (((u32)(x)[0]<<24)|((x)[1]<<16)|((x)[2]<<8)|(x)[3])


/*
** Deserialize the data blob pointed to by buf as serial type serial_type
** and store the result in pMem.  Return the number of bytes read.





*/ 
































u32 sqlite3VdbeSerialGet(
  const unsigned char *buf,     /* Buffer to deserialize from */
  u32 serial_type,              /* Serial type to deserialize */
  Mem *pMem                     /* Memory cell to write value into */
){
  u64 x;
  u32 y;
  switch( serial_type ){
    case 10:   /* Reserved for future use */
    case 11:   /* Reserved for future use */
    case 0: {  /* NULL */
      pMem->flags = MEM_Null;
      break;
    }
................................................................................
    case 3: { /* 3-byte signed integer */
      pMem->u.i = THREE_BYTE_INT(buf);
      pMem->flags = MEM_Int;
      testcase( pMem->u.i<0 );
      return 3;
    }
    case 4: { /* 4-byte signed integer */
      y = FOUR_BYTE_UINT(buf);
      pMem->u.i = (i64)*(int*)&y;
      pMem->flags = MEM_Int;
      testcase( pMem->u.i<0 );
      return 4;
    }
    case 5: { /* 6-byte signed integer */
      pMem->u.i = FOUR_BYTE_UINT(buf+2) + (((i64)1)<<32)*TWO_BYTE_INT(buf);
      pMem->flags = MEM_Int;
      testcase( pMem->u.i<0 );
      return 6;
    }
    case 6:   /* 8-byte signed integer */
    case 7: { /* IEEE floating point */
#if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
      /* Verify that integers and floating point values use the same
      ** byte order.  Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
      ** defined that 64-bit floating point values really are mixed
      ** endian.
      */
      static const u64 t1 = ((u64)0x3ff00000)<<32;
      static const double r1 = 1.0;
      u64 t2 = t1;
      swapMixedEndianFloat(t2);
      assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
#endif
      x = FOUR_BYTE_UINT(buf);
      y = FOUR_BYTE_UINT(buf+4);
      x = (x<<32) | y;
      if( serial_type==6 ){
        pMem->u.i = *(i64*)&x;
        pMem->flags = MEM_Int;
        testcase( pMem->u.i<0 );
      }else{
        assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
        swapMixedEndianFloat(x);
        memcpy(&pMem->r, &x, sizeof(x));
        pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
      }
      return 8;
    }
    case 8:    /* Integer 0 */
    case 9: {  /* Integer 1 */
      pMem->u.i = serial_type-8;
      pMem->flags = MEM_Int;
      return 0;
    }
    default: {
      static const u16 aFlag[] = { MEM_Blob|MEM_Ephem, MEM_Str|MEM_Ephem };
      u32 len = (serial_type-12)/2;
      pMem->z = (char *)buf;
      pMem->n = len;
      pMem->xDel = 0;
      pMem->flags = aFlag[serial_type&1];
      return len;
    }
  }
  return 0;
}

/*
** This routine is used to allocate sufficient space for an UnpackedRecord
** structure large enough to be used with sqlite3VdbeRecordUnpack() if
** the first argument is a pointer to KeyInfo structure pKeyInfo.
**
** The space is either allocated using sqlite3DbMallocRaw() or from within
** the unaligned buffer passed via the second and third arguments (presumably

    sqlite3BeginBenignMalloc();
    if( db->pErr==0 ) db->pErr = sqlite3ValueNew(db);
    sqlite3ValueSetStr(db->pErr, -1, p->zErrMsg, SQLITE_UTF8, SQLITE_TRANSIENT);
    sqlite3EndBenignMalloc();
    db->mallocFailed = mallocFailed;
    db->errCode = rc;
  }else{
    sqlite3Error(db, rc);
  }
  return rc;
}

#ifdef SQLITE_ENABLE_SQLLOG
/*
** If an SQLITE_CONFIG_SQLLOG hook is registered and the VM has been run, 
................................................................................
    p->zErrMsg = 0;
    if( p->runOnlyOnce ) p->expired = 1;
  }else if( p->rc && p->expired ){
    /* The expired flag was set on the VDBE before the first call
    ** to sqlite3_step(). For consistency (since sqlite3_step() was
    ** called), set the database error in this case as well.
    */
    sqlite3ErrorWithMsg(db, p->rc, p->zErrMsg ? "%s" : 0, p->zErrMsg);
    sqlite3DbFree(db, p->zErrMsg);
    p->zErrMsg = 0;
  }

  /* Reclaim all memory used by the VDBE
  */
  Cleanup(p);
................................................................................
  if( p->pNext ){
    p->pNext->pPrev = p->pPrev;
  }
  p->magic = VDBE_MAGIC_DEAD;
  p->db = 0;
  sqlite3DbFree(db, p);
}

/*
** The cursor "p" has a pending seek operation that has not yet been
** carried out.  Seek the cursor now.  If an error occurs, return
** the appropriate error code.
*/
static int SQLITE_NOINLINE handleDeferredMoveto(VdbeCursor *p){
  int res, rc;
#ifdef SQLITE_TEST
  extern int sqlite3_search_count;
#endif
  assert( p->deferredMoveto );
  assert( p->isTable );
  rc = sqlite3BtreeMovetoUnpacked(p->pCursor, 0, p->movetoTarget, 0, &res);
  if( rc ) return rc;
  p->lastRowid = p->movetoTarget;
  if( res!=0 ) return SQLITE_CORRUPT_BKPT;
  p->rowidIsValid = 1;
#ifdef SQLITE_TEST
  sqlite3_search_count++;
#endif
  p->deferredMoveto = 0;
  p->cacheStatus = CACHE_STALE;
  return SQLITE_OK;
}

/*
** Something has moved cursor "p" out of place.  Maybe the row it was
** pointed to was deleted out from under it.  Or maybe the btree was
** rebalanced.  Whatever the cause, try to restore "p" to the place it
** is suppose to be pointing.  If the row was deleted out from under the
** cursor, set the cursor to point to a NULL row.
*/
static int SQLITE_NOINLINE handleMovedCursor(VdbeCursor *p){
  int isDifferentRow, rc;
  assert( p->pCursor!=0 );
  assert( sqlite3BtreeCursorHasMoved(p->pCursor) );
  rc = sqlite3BtreeCursorRestore(p->pCursor, &isDifferentRow);
  p->cacheStatus = CACHE_STALE;
  if( isDifferentRow ) p->nullRow = 1;
  return rc;
}

/*
** Make sure the cursor p is ready to read or write the row to which it
** was last positioned.  Return an error code if an OOM fault or I/O error
** prevents us from positioning the cursor to its correct position.
**
** If a MoveTo operation is pending on the given cursor, then do that
................................................................................
** a NULL row.
**
** If the cursor is already pointing to the correct row and that row has
** not been deleted out from under the cursor, then this routine is a no-op.
*/
int sqlite3VdbeCursorMoveto(VdbeCursor *p){
  if( p->deferredMoveto ){













    return handleDeferredMoveto(p);








  }
  if( sqlite3BtreeCursorHasMoved(p->pCursor) ){
    return handleMovedCursor(p);
  }
  return SQLITE_OK;
}

/*
** The following functions:
**
................................................................................
      assert( sizeof(v)==sizeof(pMem->r) );
      memcpy(&v, &pMem->r, sizeof(v));
      swapMixedEndianFloat(v);
    }else{
      v = pMem->u.i;
    }
    len = i = sqlite3VdbeSerialTypeLen(serial_type);
    assert( i>0 );
    do{
      buf[--i] = (u8)(v&0xFF);
      v >>= 8;

    }while( i );
    return len;
  }

  /* String or blob */
  if( serial_type>=12 ){
    assert( pMem->n + ((pMem->flags & MEM_Zero)?pMem->u.nZero:0)
             == (int)sqlite3VdbeSerialTypeLen(serial_type) );
................................................................................
/* Input "x" is a sequence of unsigned characters that represent a
** big-endian integer.  Return the equivalent native integer
*/
#define ONE_BYTE_INT(x)    ((i8)(x)[0])
#define TWO_BYTE_INT(x)    (256*(i8)((x)[0])|(x)[1])
#define THREE_BYTE_INT(x)  (65536*(i8)((x)[0])|((x)[1]<<8)|(x)[2])
#define FOUR_BYTE_UINT(x)  (((u32)(x)[0]<<24)|((x)[1]<<16)|((x)[2]<<8)|(x)[3])
#define FOUR_BYTE_INT(x) (16777216*(i8)((x)[0])|((x)[1]<<16)|((x)[2]<<8)|(x)[3])

/*
** Deserialize the data blob pointed to by buf as serial type serial_type
** and store the result in pMem.  Return the number of bytes read.
**
** This function is implemented as two separate routines for performance.
** The few cases that require local variables are broken out into a separate
** routine so that in most cases the overhead of moving the stack pointer
** is avoided.
*/ 
static u32 SQLITE_NOINLINE serialGet(
  const unsigned char *buf,     /* Buffer to deserialize from */
  u32 serial_type,              /* Serial type to deserialize */
  Mem *pMem                     /* Memory cell to write value into */
){
  u64 x = FOUR_BYTE_UINT(buf);
  u32 y = FOUR_BYTE_UINT(buf+4);
  x = (x<<32) + y;
  if( serial_type==6 ){
    pMem->u.i = *(i64*)&x;
    pMem->flags = MEM_Int;
    testcase( pMem->u.i<0 );
  }else{
#if !defined(NDEBUG) && !defined(SQLITE_OMIT_FLOATING_POINT)
    /* Verify that integers and floating point values use the same
    ** byte order.  Or, that if SQLITE_MIXED_ENDIAN_64BIT_FLOAT is
    ** defined that 64-bit floating point values really are mixed
    ** endian.
    */
    static const u64 t1 = ((u64)0x3ff00000)<<32;
    static const double r1 = 1.0;
    u64 t2 = t1;
    swapMixedEndianFloat(t2);
    assert( sizeof(r1)==sizeof(t2) && memcmp(&r1, &t2, sizeof(r1))==0 );
#endif
    assert( sizeof(x)==8 && sizeof(pMem->r)==8 );
    swapMixedEndianFloat(x);
    memcpy(&pMem->r, &x, sizeof(x));
    pMem->flags = sqlite3IsNaN(pMem->r) ? MEM_Null : MEM_Real;
  }
  return 8;
}
u32 sqlite3VdbeSerialGet(
  const unsigned char *buf,     /* Buffer to deserialize from */
  u32 serial_type,              /* Serial type to deserialize */
  Mem *pMem                     /* Memory cell to write value into */
){


  switch( serial_type ){
    case 10:   /* Reserved for future use */
    case 11:   /* Reserved for future use */
    case 0: {  /* NULL */
      pMem->flags = MEM_Null;
      break;
    }
................................................................................
    case 3: { /* 3-byte signed integer */
      pMem->u.i = THREE_BYTE_INT(buf);
      pMem->flags = MEM_Int;
      testcase( pMem->u.i<0 );
      return 3;
    }
    case 4: { /* 4-byte signed integer */
      pMem->u.i = FOUR_BYTE_INT(buf);

      pMem->flags = MEM_Int;
      testcase( pMem->u.i<0 );
      return 4;
    }
    case 5: { /* 6-byte signed integer */
      pMem->u.i = FOUR_BYTE_UINT(buf+2) + (((i64)1)<<32)*TWO_BYTE_INT(buf);
      pMem->flags = MEM_Int;
      testcase( pMem->u.i<0 );
      return 6;
    }
    case 6:   /* 8-byte signed integer */
    case 7: { /* IEEE floating point */
      /* These use local variables, so do them in a separate routine
      ** to avoid having to move the frame pointer in the common case */
      return serialGet(buf,serial_type,pMem);























    }
    case 8:    /* Integer 0 */
    case 9: {  /* Integer 1 */
      pMem->u.i = serial_type-8;
      pMem->flags = MEM_Int;
      return 0;
    }
    default: {
      static const u16 aFlag[] = { MEM_Blob|MEM_Ephem, MEM_Str|MEM_Ephem };

      pMem->z = (char *)buf;
      pMem->n = (serial_type-12)/2;
      pMem->xDel = 0;
      pMem->flags = aFlag[serial_type&1];
      return pMem->n;
    }
  }
  return 0;
}

/*
** This routine is used to allocate sufficient space for an UnpackedRecord
** structure large enough to be used with sqlite3VdbeRecordUnpack() if
** the first argument is a pointer to KeyInfo structure pKeyInfo.
**
** The space is either allocated using sqlite3DbMallocRaw() or from within
** the unaligned buffer passed via the second and third arguments (presumably

blob_open_out:
  if( rc==SQLITE_OK && db->mallocFailed==0 ){
    *ppBlob = (sqlite3_blob *)pBlob;
  }else{
    if( pBlob && pBlob->pStmt ) sqlite3VdbeFinalize((Vdbe *)pBlob->pStmt);
    sqlite3DbFree(db, pBlob);
  }
  sqlite3Error(db, rc, (zErr ? "%s" : 0), zErr);
  sqlite3DbFree(db, zErr);
  sqlite3ParserReset(pParse);
  sqlite3StackFree(db, pParse);
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}
................................................................................
  db = p->db;
  sqlite3_mutex_enter(db->mutex);
  v = (Vdbe*)p->pStmt;

  if( n<0 || iOffset<0 || (iOffset+n)>p->nByte ){
    /* Request is out of range. Return a transient error. */
    rc = SQLITE_ERROR;
    sqlite3Error(db, SQLITE_ERROR, 0);
  }else if( v==0 ){
    /* If there is no statement handle, then the blob-handle has
    ** already been invalidated. Return SQLITE_ABORT in this case.
    */
    rc = SQLITE_ABORT;
  }else{
    /* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is
................................................................................
    ** already been invalidated. Return SQLITE_ABORT in this case.
    */
    rc = SQLITE_ABORT;
  }else{
    char *zErr;
    rc = blobSeekToRow(p, iRow, &zErr);
    if( rc!=SQLITE_OK ){
      sqlite3Error(db, rc, (zErr ? "%s" : 0), zErr);
      sqlite3DbFree(db, zErr);
    }
    assert( rc!=SQLITE_SCHEMA );
  }

  rc = sqlite3ApiExit(db, rc);
  assert( rc==SQLITE_OK || p->pStmt==0 );
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

#endif /* #ifndef SQLITE_OMIT_INCRBLOB */

blob_open_out:
  if( rc==SQLITE_OK && db->mallocFailed==0 ){
    *ppBlob = (sqlite3_blob *)pBlob;
  }else{
    if( pBlob && pBlob->pStmt ) sqlite3VdbeFinalize((Vdbe *)pBlob->pStmt);
    sqlite3DbFree(db, pBlob);
  }
  sqlite3ErrorWithMsg(db, rc, (zErr ? "%s" : 0), zErr);
  sqlite3DbFree(db, zErr);
  sqlite3ParserReset(pParse);
  sqlite3StackFree(db, pParse);
  rc = sqlite3ApiExit(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}
................................................................................
  db = p->db;
  sqlite3_mutex_enter(db->mutex);
  v = (Vdbe*)p->pStmt;

  if( n<0 || iOffset<0 || (iOffset+n)>p->nByte ){
    /* Request is out of range. Return a transient error. */
    rc = SQLITE_ERROR;
    sqlite3Error(db, SQLITE_ERROR);
  }else if( v==0 ){
    /* If there is no statement handle, then the blob-handle has
    ** already been invalidated. Return SQLITE_ABORT in this case.
    */
    rc = SQLITE_ABORT;
  }else{
    /* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is
................................................................................
    ** already been invalidated. Return SQLITE_ABORT in this case.
    */
    rc = SQLITE_ABORT;
  }else{
    char *zErr;
    rc = blobSeekToRow(p, iRow, &zErr);
    if( rc!=SQLITE_OK ){
      sqlite3ErrorWithMsg(db, rc, (zErr ? "%s" : 0), zErr);
      sqlite3DbFree(db, zErr);
    }
    assert( rc!=SQLITE_SCHEMA );
  }

  rc = sqlite3ApiExit(db, rc);
  assert( rc==SQLITE_OK || p->pStmt==0 );
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

#endif /* #ifndef SQLITE_OMIT_INCRBLOB */

      pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n);
      bPreserve = 0;
    }else{
      sqlite3DbFree(pMem->db, pMem->zMalloc);
      pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
    }
    if( pMem->zMalloc==0 ){
      VdbeMemRelease(pMem);
      pMem->z = 0;
      pMem->flags = MEM_Null;  
      return SQLITE_NOMEM;
    }
  }

  if( pMem->z && bPreserve && pMem->z!=pMem->zMalloc ){
................................................................................
}

/*
** Add MEM_Str to the set of representations for the given Mem.  Numbers
** are converted using sqlite3_snprintf().  Converting a BLOB to a string
** is a no-op.
**
** Existing representations MEM_Int and MEM_Real are *not* invalidated.

**
** A MEM_Null value will never be passed to this function. This function is
** used for converting values to text for returning to the user (i.e. via
** sqlite3_value_text()), or for ensuring that values to be used as btree
** keys are strings. In the former case a NULL pointer is returned the
** user and the later is an internal programming error.
*/
int sqlite3VdbeMemStringify(Mem *pMem, int enc){
  int rc = SQLITE_OK;
  int fg = pMem->flags;
  const int nByte = 32;

  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( !(fg&MEM_Zero) );
  assert( !(fg&(MEM_Str|MEM_Blob)) );
  assert( fg&(MEM_Int|MEM_Real) );
................................................................................
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );


  if( sqlite3VdbeMemGrow(pMem, nByte, 0) ){
    return SQLITE_NOMEM;
  }

  /* For a Real or Integer, use sqlite3_mprintf() to produce the UTF-8
  ** string representation of the value. Then, if the required encoding
  ** is UTF-16le or UTF-16be do a translation.
  ** 
  ** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16.
  */
  if( fg & MEM_Int ){
    sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
................................................................................
  }else{
    assert( fg & MEM_Real );
    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->r);
  }
  pMem->n = sqlite3Strlen30(pMem->z);
  pMem->enc = SQLITE_UTF8;
  pMem->flags |= MEM_Str|MEM_Term;

  sqlite3VdbeChangeEncoding(pMem, enc);
  return rc;
}

/*
** Memory cell pMem contains the context of an aggregate function.
** This routine calls the finalize method for that function.  The
** result of the aggregate is stored back into pMem.
**
................................................................................
  return rc;
}

/*
** If the memory cell contains a string value that must be freed by
** invoking an external callback, free it now. Calling this function
** does not free any Mem.zMalloc buffer.



*/
void sqlite3VdbeMemReleaseExternal(Mem *p){
  assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
  if( p->flags&MEM_Agg ){
    sqlite3VdbeMemFinalize(p, p->u.pDef);
    assert( (p->flags & MEM_Agg)==0 );
    sqlite3VdbeMemRelease(p);
................................................................................
    p->xDel = 0;
  }else if( p->flags&MEM_RowSet ){
    sqlite3RowSetClear(p->u.pRowSet);
  }else if( p->flags&MEM_Frame ){
    sqlite3VdbeMemSetNull(p);
  }
}




















/*
** Release any memory held by the Mem. This may leave the Mem in an
** inconsistent state, for example with (Mem.z==0) and
** (Mem.flags==MEM_Str).
*/
void sqlite3VdbeMemRelease(Mem *p){
  assert( sqlite3VdbeCheckMemInvariants(p) );

  VdbeMemRelease(p);
  if( p->zMalloc ){
    sqlite3DbFree(p->db, p->zMalloc);
    p->zMalloc = 0;
  }
  p->z = 0;
  assert( p->xDel==0 );  /* Zeroed by VdbeMemRelease() above */
}

/*
** Convert a 64-bit IEEE double into a 64-bit signed integer.
** If the double is out of range of a 64-bit signed integer then
** return the closest available 64-bit signed integer.
*/
................................................................................
  if( flags & MEM_Int ){
    return pMem->u.i;
  }else if( flags & MEM_Real ){
    return doubleToInt64(pMem->r);
  }else if( flags & (MEM_Str|MEM_Blob) ){
    i64 value = 0;
    assert( pMem->z || pMem->n==0 );
    testcase( pMem->z==0 );
    sqlite3Atoi64(pMem->z, &value, pMem->n, pMem->enc);
    return value;
  }else{
    return 0;
  }
}

................................................................................
      sqlite3VdbeIntegerAffinity(pMem);
    }
  }
  assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))!=0 );
  pMem->flags &= ~(MEM_Str|MEM_Blob);
  return SQLITE_OK;
}














































/*
** Delete any previous value and set the value stored in *pMem to NULL.
*/
void sqlite3VdbeMemSetNull(Mem *pMem){
  if( pMem->flags & MEM_Frame ){
    VdbeFrame *pFrame = pMem->u.pFrame;
................................................................................
** Make an shallow copy of pFrom into pTo.  Prior contents of
** pTo are freed.  The pFrom->z field is not duplicated.  If
** pFrom->z is used, then pTo->z points to the same thing as pFrom->z
** and flags gets srcType (either MEM_Ephem or MEM_Static).
*/
void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){
  assert( (pFrom->flags & MEM_RowSet)==0 );
  VdbeMemRelease(pTo);
  memcpy(pTo, pFrom, MEMCELLSIZE);
  pTo->xDel = 0;
  if( (pFrom->flags&MEM_Static)==0 ){
    pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem);
    assert( srcType==MEM_Ephem || srcType==MEM_Static );
    pTo->flags |= srcType;
  }
................................................................................
** Make a full copy of pFrom into pTo.  Prior contents of pTo are
** freed before the copy is made.
*/
int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
  int rc = SQLITE_OK;

  assert( (pFrom->flags & MEM_RowSet)==0 );
  VdbeMemRelease(pTo);
  memcpy(pTo, pFrom, MEMCELLSIZE);
  pTo->flags &= ~MEM_Dyn;
  pTo->xDel = 0;

  if( pTo->flags&(MEM_Str|MEM_Blob) ){
    if( 0==(pFrom->flags&MEM_Static) ){
      pTo->flags |= MEM_Ephem;
................................................................................
      if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){
        return 0;
      }
    }
    sqlite3VdbeMemNulTerminate(pVal); /* IMP: R-31275-44060 */
  }else{
    assert( (pVal->flags&MEM_Blob)==0 );
    sqlite3VdbeMemStringify(pVal, enc);
    assert( 0==(1&SQLITE_PTR_TO_INT(pVal->z)) );
  }
  assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || pVal->db==0
              || pVal->db->mallocFailed );
  if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
    return pVal->z;
  }else{
................................................................................
  const char *zNeg = "";
  int rc = SQLITE_OK;

  if( !pExpr ){
    *ppVal = 0;
    return SQLITE_OK;
  }
  op = pExpr->op;
  if( NEVER(op==TK_REGISTER) ) op = pExpr->op2;












  /* Handle negative integers in a single step.  This is needed in the
  ** case when the value is -9223372036854775808.
  */
  if( op==TK_UMINUS
   && (pExpr->pLeft->op==TK_INTEGER || pExpr->pLeft->op==TK_FLOAT) ){
    pExpr = pExpr->pLeft;
................................................................................

  nRet = 1 + nSerial + nVal;
  aRet = sqlite3DbMallocRaw(db, nRet);
  if( aRet==0 ){
    sqlite3_result_error_nomem(context);
  }else{
    aRet[0] = nSerial+1;
    sqlite3PutVarint(&aRet[1], iSerial);
    sqlite3VdbeSerialPut(&aRet[1+nSerial], argv[0], iSerial);
    sqlite3_result_blob(context, aRet, nRet, SQLITE_TRANSIENT);
    sqlite3DbFree(db, aRet);
  }
}

/*

      pMem->z = pMem->zMalloc = sqlite3DbReallocOrFree(pMem->db, pMem->z, n);
      bPreserve = 0;
    }else{
      sqlite3DbFree(pMem->db, pMem->zMalloc);
      pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, n);
    }
    if( pMem->zMalloc==0 ){
      VdbeMemReleaseExtern(pMem);
      pMem->z = 0;
      pMem->flags = MEM_Null;  
      return SQLITE_NOMEM;
    }
  }

  if( pMem->z && bPreserve && pMem->z!=pMem->zMalloc ){
................................................................................
}

/*
** Add MEM_Str to the set of representations for the given Mem.  Numbers
** are converted using sqlite3_snprintf().  Converting a BLOB to a string
** is a no-op.
**
** Existing representations MEM_Int and MEM_Real are invalidated if
** bForce is true but are retained if bForce is false.
**
** A MEM_Null value will never be passed to this function. This function is
** used for converting values to text for returning to the user (i.e. via
** sqlite3_value_text()), or for ensuring that values to be used as btree
** keys are strings. In the former case a NULL pointer is returned the
** user and the later is an internal programming error.
*/
int sqlite3VdbeMemStringify(Mem *pMem, u8 enc, u8 bForce){

  int fg = pMem->flags;
  const int nByte = 32;

  assert( pMem->db==0 || sqlite3_mutex_held(pMem->db->mutex) );
  assert( !(fg&MEM_Zero) );
  assert( !(fg&(MEM_Str|MEM_Blob)) );
  assert( fg&(MEM_Int|MEM_Real) );
................................................................................
  assert( EIGHT_BYTE_ALIGNMENT(pMem) );


  if( sqlite3VdbeMemGrow(pMem, nByte, 0) ){
    return SQLITE_NOMEM;
  }

  /* For a Real or Integer, use sqlite3_snprintf() to produce the UTF-8
  ** string representation of the value. Then, if the required encoding
  ** is UTF-16le or UTF-16be do a translation.
  ** 
  ** FIX ME: It would be better if sqlite3_snprintf() could do UTF-16.
  */
  if( fg & MEM_Int ){
    sqlite3_snprintf(nByte, pMem->z, "%lld", pMem->u.i);
................................................................................
  }else{
    assert( fg & MEM_Real );
    sqlite3_snprintf(nByte, pMem->z, "%!.15g", pMem->r);
  }
  pMem->n = sqlite3Strlen30(pMem->z);
  pMem->enc = SQLITE_UTF8;
  pMem->flags |= MEM_Str|MEM_Term;
  if( bForce ) pMem->flags &= ~(MEM_Int|MEM_Real);
  sqlite3VdbeChangeEncoding(pMem, enc);
  return SQLITE_OK;
}

/*
** Memory cell pMem contains the context of an aggregate function.
** This routine calls the finalize method for that function.  The
** result of the aggregate is stored back into pMem.
**
................................................................................
  return rc;
}

/*
** If the memory cell contains a string value that must be freed by
** invoking an external callback, free it now. Calling this function
** does not free any Mem.zMalloc buffer.
**
** The VdbeMemReleaseExtern() macro invokes this routine if only if there
** is work for this routine to do.
*/
void sqlite3VdbeMemReleaseExternal(Mem *p){
  assert( p->db==0 || sqlite3_mutex_held(p->db->mutex) );
  if( p->flags&MEM_Agg ){
    sqlite3VdbeMemFinalize(p, p->u.pDef);
    assert( (p->flags & MEM_Agg)==0 );
    sqlite3VdbeMemRelease(p);
................................................................................
    p->xDel = 0;
  }else if( p->flags&MEM_RowSet ){
    sqlite3RowSetClear(p->u.pRowSet);
  }else if( p->flags&MEM_Frame ){
    sqlite3VdbeMemSetNull(p);
  }
}

/*
** Release memory held by the Mem p, both external memory cleared
** by p->xDel and memory in p->zMalloc.
**
** This is a helper routine invoked by sqlite3VdbeMemRelease() in
** the uncommon case when there really is memory in p that is
** need of freeing.
*/
static SQLITE_NOINLINE void vdbeMemRelease(Mem *p){
  if( VdbeMemDynamic(p) ){
    sqlite3VdbeMemReleaseExternal(p);
  }
  if( p->zMalloc ){
    sqlite3DbFree(p->db, p->zMalloc);
    p->zMalloc = 0;
  }
  p->z = 0;
}

/*
** Release any memory held by the Mem. This may leave the Mem in an
** inconsistent state, for example with (Mem.z==0) and
** (Mem.flags==MEM_Str).
*/
void sqlite3VdbeMemRelease(Mem *p){
  assert( sqlite3VdbeCheckMemInvariants(p) );
  if( VdbeMemDynamic(p) || p->zMalloc ){
    vdbeMemRelease(p);

  }else{
    p->z = 0;
  }

  assert( p->xDel==0 );
}

/*
** Convert a 64-bit IEEE double into a 64-bit signed integer.
** If the double is out of range of a 64-bit signed integer then
** return the closest available 64-bit signed integer.
*/
................................................................................
  if( flags & MEM_Int ){
    return pMem->u.i;
  }else if( flags & MEM_Real ){
    return doubleToInt64(pMem->r);
  }else if( flags & (MEM_Str|MEM_Blob) ){
    i64 value = 0;
    assert( pMem->z || pMem->n==0 );

    sqlite3Atoi64(pMem->z, &value, pMem->n, pMem->enc);
    return value;
  }else{
    return 0;
  }
}

................................................................................
      sqlite3VdbeIntegerAffinity(pMem);
    }
  }
  assert( (pMem->flags & (MEM_Int|MEM_Real|MEM_Null))!=0 );
  pMem->flags &= ~(MEM_Str|MEM_Blob);
  return SQLITE_OK;
}

/*
** Cast the datatype of the value in pMem according to the affinity
** "aff".  Casting is different from applying affinity in that a cast
** is forced.  In other words, the value is converted into the desired
** affinity even if that results in loss of data.  This routine is
** used (for example) to implement the SQL "cast()" operator.
*/
void sqlite3VdbeMemCast(Mem *pMem, u8 aff, u8 encoding){
  if( pMem->flags & MEM_Null ) return;
  switch( aff ){
    case SQLITE_AFF_NONE: {   /* Really a cast to BLOB */
      if( (pMem->flags & MEM_Blob)==0 ){
        sqlite3ValueApplyAffinity(pMem, SQLITE_AFF_TEXT, encoding);
        assert( pMem->flags & MEM_Str || pMem->db->mallocFailed );
        MemSetTypeFlag(pMem, MEM_Blob);
      }else{
        pMem->flags &= ~(MEM_TypeMask&~MEM_Blob);
      }
      break;
    }
    case SQLITE_AFF_NUMERIC: {
      sqlite3VdbeMemNumerify(pMem);
      break;
    }
    case SQLITE_AFF_INTEGER: {
      sqlite3VdbeMemIntegerify(pMem);
      break;
    }
    case SQLITE_AFF_REAL: {
      sqlite3VdbeMemRealify(pMem);
      break;
    }
    default: {
      assert( aff==SQLITE_AFF_TEXT );
      assert( MEM_Str==(MEM_Blob>>3) );
      pMem->flags |= (pMem->flags&MEM_Blob)>>3;
      sqlite3ValueApplyAffinity(pMem, SQLITE_AFF_TEXT, encoding);
      assert( pMem->flags & MEM_Str || pMem->db->mallocFailed );
      pMem->flags &= ~(MEM_Int|MEM_Real|MEM_Blob|MEM_Zero);
      break;
    }
  }
}


/*
** Delete any previous value and set the value stored in *pMem to NULL.
*/
void sqlite3VdbeMemSetNull(Mem *pMem){
  if( pMem->flags & MEM_Frame ){
    VdbeFrame *pFrame = pMem->u.pFrame;
................................................................................
** Make an shallow copy of pFrom into pTo.  Prior contents of
** pTo are freed.  The pFrom->z field is not duplicated.  If
** pFrom->z is used, then pTo->z points to the same thing as pFrom->z
** and flags gets srcType (either MEM_Ephem or MEM_Static).
*/
void sqlite3VdbeMemShallowCopy(Mem *pTo, const Mem *pFrom, int srcType){
  assert( (pFrom->flags & MEM_RowSet)==0 );
  VdbeMemReleaseExtern(pTo);
  memcpy(pTo, pFrom, MEMCELLSIZE);
  pTo->xDel = 0;
  if( (pFrom->flags&MEM_Static)==0 ){
    pTo->flags &= ~(MEM_Dyn|MEM_Static|MEM_Ephem);
    assert( srcType==MEM_Ephem || srcType==MEM_Static );
    pTo->flags |= srcType;
  }
................................................................................
** Make a full copy of pFrom into pTo.  Prior contents of pTo are
** freed before the copy is made.
*/
int sqlite3VdbeMemCopy(Mem *pTo, const Mem *pFrom){
  int rc = SQLITE_OK;

  assert( (pFrom->flags & MEM_RowSet)==0 );
  VdbeMemReleaseExtern(pTo);
  memcpy(pTo, pFrom, MEMCELLSIZE);
  pTo->flags &= ~MEM_Dyn;
  pTo->xDel = 0;

  if( pTo->flags&(MEM_Str|MEM_Blob) ){
    if( 0==(pFrom->flags&MEM_Static) ){
      pTo->flags |= MEM_Ephem;
................................................................................
      if( sqlite3VdbeMemMakeWriteable(pVal)!=SQLITE_OK ){
        return 0;
      }
    }
    sqlite3VdbeMemNulTerminate(pVal); /* IMP: R-31275-44060 */
  }else{
    assert( (pVal->flags&MEM_Blob)==0 );
    sqlite3VdbeMemStringify(pVal, enc, 0);
    assert( 0==(1&SQLITE_PTR_TO_INT(pVal->z)) );
  }
  assert(pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) || pVal->db==0
              || pVal->db->mallocFailed );
  if( pVal->enc==(enc & ~SQLITE_UTF16_ALIGNED) ){
    return pVal->z;
  }else{
................................................................................
  const char *zNeg = "";
  int rc = SQLITE_OK;

  if( !pExpr ){
    *ppVal = 0;
    return SQLITE_OK;
  }
  while( (op = pExpr->op)==TK_UPLUS ) pExpr = pExpr->pLeft;
  if( NEVER(op==TK_REGISTER) ) op = pExpr->op2;

  if( op==TK_CAST ){
    u8 aff = sqlite3AffinityType(pExpr->u.zToken,0);
    rc = valueFromExpr(db, pExpr->pLeft, enc, aff, ppVal, pCtx);
    testcase( rc!=SQLITE_OK );
    if( *ppVal ){
      sqlite3VdbeMemCast(*ppVal, aff, SQLITE_UTF8);
      sqlite3ValueApplyAffinity(*ppVal, affinity, SQLITE_UTF8);
    }
    return rc;
  }

  /* Handle negative integers in a single step.  This is needed in the
  ** case when the value is -9223372036854775808.
  */
  if( op==TK_UMINUS
   && (pExpr->pLeft->op==TK_INTEGER || pExpr->pLeft->op==TK_FLOAT) ){
    pExpr = pExpr->pLeft;
................................................................................

  nRet = 1 + nSerial + nVal;
  aRet = sqlite3DbMallocRaw(db, nRet);
  if( aRet==0 ){
    sqlite3_result_error_nomem(context);
  }else{
    aRet[0] = nSerial+1;
    putVarint32(&aRet[1], iSerial);
    sqlite3VdbeSerialPut(&aRet[1+nSerial], argv[0], iSerial);
    sqlite3_result_blob(context, aRet, nRet, SQLITE_TRANSIENT);
    sqlite3DbFree(db, aRet);
  }
}

/*

  void (*xDestroy)(void *)        /* Module destructor function */
){
  int rc = SQLITE_OK;
  int nName;

  sqlite3_mutex_enter(db->mutex);
  nName = sqlite3Strlen30(zName);
  if( sqlite3HashFind(&db->aModule, zName, nName) ){
    rc = SQLITE_MISUSE_BKPT;
  }else{
    Module *pMod;
    pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
    if( pMod ){
      Module *pDel;
      char *zCopy = (char *)(&pMod[1]);
      memcpy(zCopy, zName, nName+1);
      pMod->zName = zCopy;
      pMod->pModule = pModule;
      pMod->pAux = pAux;
      pMod->xDestroy = xDestroy;
      pDel = (Module *)sqlite3HashInsert(&db->aModule,zCopy,nName,(void*)pMod);
      assert( pDel==0 || pDel==pMod );
      if( pDel ){
        db->mallocFailed = 1;
        sqlite3DbFree(db, pDel);
      }
    }
  }
................................................................................
  ** the first time the virtual table is used in an SQL statement. This
  ** allows a schema that contains virtual tables to be loaded before
  ** the required virtual table implementations are registered.  */
  else {
    Table *pOld;
    Schema *pSchema = pTab->pSchema;
    const char *zName = pTab->zName;
    int nName = sqlite3Strlen30(zName);
    assert( sqlite3SchemaMutexHeld(db, 0, pSchema) );
    pOld = sqlite3HashInsert(&pSchema->tblHash, zName, nName, pTab);
    if( pOld ){
      db->mallocFailed = 1;
      assert( pTab==pOld );  /* Malloc must have failed inside HashInsert() */
      return;
    }
    pParse->pNewTable = 0;
  }
................................................................................
  assert( pTab );
  if( (pTab->tabFlags & TF_Virtual)==0 || sqlite3GetVTable(db, pTab) ){
    return SQLITE_OK;
  }

  /* Locate the required virtual table module */
  zMod = pTab->azModuleArg[0];
  pMod = (Module*)sqlite3HashFind(&db->aModule, zMod, sqlite3Strlen30(zMod));

  if( !pMod ){
    const char *zModule = pTab->azModuleArg[0];
    sqlite3ErrorMsg(pParse, "no such module: %s", zModule);
    rc = SQLITE_ERROR;
  }else{
    char *zErr = 0;
................................................................................
  const char *zMod;

  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
  assert( pTab && (pTab->tabFlags & TF_Virtual)!=0 && !pTab->pVTable );

  /* Locate the required virtual table module */
  zMod = pTab->azModuleArg[0];
  pMod = (Module*)sqlite3HashFind(&db->aModule, zMod, sqlite3Strlen30(zMod));

  /* If the module has been registered and includes a Create method, 
  ** invoke it now. If the module has not been registered, return an 
  ** error. Otherwise, do nothing.
  */
  if( !pMod ){
    *pzErr = sqlite3MPrintf(db, "no such module: %s", zMod);
................................................................................

  int rc = SQLITE_OK;
  Table *pTab;
  char *zErr = 0;

  sqlite3_mutex_enter(db->mutex);
  if( !db->pVtabCtx || !(pTab = db->pVtabCtx->pTab) ){
    sqlite3Error(db, SQLITE_MISUSE, 0);
    sqlite3_mutex_leave(db->mutex);
    return SQLITE_MISUSE_BKPT;
  }
  assert( (pTab->tabFlags & TF_Virtual)!=0 );

  pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
  if( pParse==0 ){
................................................................................
        pTab->aCol = pParse->pNewTable->aCol;
        pTab->nCol = pParse->pNewTable->nCol;
        pParse->pNewTable->nCol = 0;
        pParse->pNewTable->aCol = 0;
      }
      db->pVtabCtx->pTab = 0;
    }else{
      sqlite3Error(db, SQLITE_ERROR, (zErr ? "%s" : 0), zErr);
      sqlite3DbFree(db, zErr);
      rc = SQLITE_ERROR;
    }
    pParse->declareVtab = 0;
  
    if( pParse->pVdbe ){
      sqlite3VdbeFinalize(pParse->pVdbe);
................................................................................
    }
    default:
      rc = SQLITE_MISUSE_BKPT;
      break;
  }
  va_end(ap);

  if( rc!=SQLITE_OK ) sqlite3Error(db, rc, 0);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

#endif /* SQLITE_OMIT_VIRTUALTABLE */

  void (*xDestroy)(void *)        /* Module destructor function */
){
  int rc = SQLITE_OK;
  int nName;

  sqlite3_mutex_enter(db->mutex);
  nName = sqlite3Strlen30(zName);
  if( sqlite3HashFind(&db->aModule, zName) ){
    rc = SQLITE_MISUSE_BKPT;
  }else{
    Module *pMod;
    pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
    if( pMod ){
      Module *pDel;
      char *zCopy = (char *)(&pMod[1]);
      memcpy(zCopy, zName, nName+1);
      pMod->zName = zCopy;
      pMod->pModule = pModule;
      pMod->pAux = pAux;
      pMod->xDestroy = xDestroy;
      pDel = (Module *)sqlite3HashInsert(&db->aModule,zCopy,(void*)pMod);
      assert( pDel==0 || pDel==pMod );
      if( pDel ){
        db->mallocFailed = 1;
        sqlite3DbFree(db, pDel);
      }
    }
  }
................................................................................
  ** the first time the virtual table is used in an SQL statement. This
  ** allows a schema that contains virtual tables to be loaded before
  ** the required virtual table implementations are registered.  */
  else {
    Table *pOld;
    Schema *pSchema = pTab->pSchema;
    const char *zName = pTab->zName;

    assert( sqlite3SchemaMutexHeld(db, 0, pSchema) );
    pOld = sqlite3HashInsert(&pSchema->tblHash, zName, pTab);
    if( pOld ){
      db->mallocFailed = 1;
      assert( pTab==pOld );  /* Malloc must have failed inside HashInsert() */
      return;
    }
    pParse->pNewTable = 0;
  }
................................................................................
  assert( pTab );
  if( (pTab->tabFlags & TF_Virtual)==0 || sqlite3GetVTable(db, pTab) ){
    return SQLITE_OK;
  }

  /* Locate the required virtual table module */
  zMod = pTab->azModuleArg[0];
  pMod = (Module*)sqlite3HashFind(&db->aModule, zMod);

  if( !pMod ){
    const char *zModule = pTab->azModuleArg[0];
    sqlite3ErrorMsg(pParse, "no such module: %s", zModule);
    rc = SQLITE_ERROR;
  }else{
    char *zErr = 0;
................................................................................
  const char *zMod;

  pTab = sqlite3FindTable(db, zTab, db->aDb[iDb].zName);
  assert( pTab && (pTab->tabFlags & TF_Virtual)!=0 && !pTab->pVTable );

  /* Locate the required virtual table module */
  zMod = pTab->azModuleArg[0];
  pMod = (Module*)sqlite3HashFind(&db->aModule, zMod);

  /* If the module has been registered and includes a Create method, 
  ** invoke it now. If the module has not been registered, return an 
  ** error. Otherwise, do nothing.
  */
  if( !pMod ){
    *pzErr = sqlite3MPrintf(db, "no such module: %s", zMod);
................................................................................

  int rc = SQLITE_OK;
  Table *pTab;
  char *zErr = 0;

  sqlite3_mutex_enter(db->mutex);
  if( !db->pVtabCtx || !(pTab = db->pVtabCtx->pTab) ){
    sqlite3Error(db, SQLITE_MISUSE);
    sqlite3_mutex_leave(db->mutex);
    return SQLITE_MISUSE_BKPT;
  }
  assert( (pTab->tabFlags & TF_Virtual)!=0 );

  pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
  if( pParse==0 ){
................................................................................
        pTab->aCol = pParse->pNewTable->aCol;
        pTab->nCol = pParse->pNewTable->nCol;
        pParse->pNewTable->nCol = 0;
        pParse->pNewTable->aCol = 0;
      }
      db->pVtabCtx->pTab = 0;
    }else{
      sqlite3ErrorWithMsg(db, SQLITE_ERROR, (zErr ? "%s" : 0), zErr);
      sqlite3DbFree(db, zErr);
      rc = SQLITE_ERROR;
    }
    pParse->declareVtab = 0;
  
    if( pParse->pVdbe ){
      sqlite3VdbeFinalize(pParse->pVdbe);
................................................................................
    }
    default:
      rc = SQLITE_MISUSE_BKPT;
      break;
  }
  va_end(ap);

  if( rc!=SQLITE_OK ) sqlite3Error(db, rc);
  sqlite3_mutex_leave(db->mutex);
  return rc;
}

#endif /* SQLITE_OMIT_VIRTUALTABLE */

        rc = sqlite3Stat4ProbeSetValue(pParse, p, &pRec, pExpr, aff, nEq, &bOk);
        if( rc==SQLITE_OK && bOk ){
          tRowcnt iNew;
          whereKeyStats(pParse, p, pRec, 0, a);
          iNew = a[0] + ((pLower->eOperator & WO_GT) ? a[1] : 0);
          if( iNew>iLower ) iLower = iNew;
          nOut--;

        }
      }

      /* If possible, improve on the iUpper estimate using ($P:$U). */
      if( pUpper ){
        int bOk;                    /* True if value is extracted from pExpr */
        Expr *pExpr = pUpper->pExpr->pRight;
................................................................................
        rc = sqlite3Stat4ProbeSetValue(pParse, p, &pRec, pExpr, aff, nEq, &bOk);
        if( rc==SQLITE_OK && bOk ){
          tRowcnt iNew;
          whereKeyStats(pParse, p, pRec, 1, a);
          iNew = a[0] + ((pUpper->eOperator & WO_LE) ? a[1] : 0);
          if( iNew<iUpper ) iUpper = iNew;
          nOut--;

        }
      }

      pBuilder->pRec = pRec;
      if( rc==SQLITE_OK ){
        if( iUpper>iLower ){
          nNew = sqlite3LogEst(iUpper - iLower);
        }else{
          nNew = 10;        assert( 10==sqlite3LogEst(2) );
        }
        if( nNew<nOut ){
          nOut = nNew;
        }
        pLoop->nOut = (LogEst)nOut;
        WHERETRACE(0x10, ("range scan regions: %u..%u  est=%d\n",
                           (u32)iLower, (u32)iUpper, nOut));
        return SQLITE_OK;
      }
    }else{
      int bDone = 0;
      rc = whereRangeSkipScanEst(pParse, pLower, pUpper, pLoop, &bDone);
      if( bDone ) return rc;
    }
  }
#else
  UNUSED_PARAMETER(pParse);
  UNUSED_PARAMETER(pBuilder);
#endif
  assert( pLower || pUpper );

  assert( pUpper==0 || (pUpper->wtFlags & TERM_VNULL)==0 );
  nNew = whereRangeAdjust(pLower, nOut);
  nNew = whereRangeAdjust(pUpper, nNew);

  /* TUNING: If there is both an upper and lower limit, assume the range is
  ** reduced by an additional 75%. This means that, by default, an open-ended
  ** range query (e.g. col > ?) is assumed to match 1/4 of the rows in the

        rc = sqlite3Stat4ProbeSetValue(pParse, p, &pRec, pExpr, aff, nEq, &bOk);
        if( rc==SQLITE_OK && bOk ){
          tRowcnt iNew;
          whereKeyStats(pParse, p, pRec, 0, a);
          iNew = a[0] + ((pLower->eOperator & WO_GT) ? a[1] : 0);
          if( iNew>iLower ) iLower = iNew;
          nOut--;
          pLower = 0;
        }
      }

      /* If possible, improve on the iUpper estimate using ($P:$U). */
      if( pUpper ){
        int bOk;                    /* True if value is extracted from pExpr */
        Expr *pExpr = pUpper->pExpr->pRight;
................................................................................
        rc = sqlite3Stat4ProbeSetValue(pParse, p, &pRec, pExpr, aff, nEq, &bOk);
        if( rc==SQLITE_OK && bOk ){
          tRowcnt iNew;
          whereKeyStats(pParse, p, pRec, 1, a);
          iNew = a[0] + ((pUpper->eOperator & WO_LE) ? a[1] : 0);
          if( iNew<iUpper ) iUpper = iNew;
          nOut--;
          pUpper = 0;
        }
      }

      pBuilder->pRec = pRec;
      if( rc==SQLITE_OK ){
        if( iUpper>iLower ){
          nNew = sqlite3LogEst(iUpper - iLower);
        }else{
          nNew = 10;        assert( 10==sqlite3LogEst(2) );
        }
        if( nNew<nOut ){
          nOut = nNew;
        }

        WHERETRACE(0x10, ("range scan regions: %u..%u  est=%d\n",
                           (u32)iLower, (u32)iUpper, nOut));

      }
    }else{
      int bDone = 0;
      rc = whereRangeSkipScanEst(pParse, pLower, pUpper, pLoop, &bDone);
      if( bDone ) return rc;
    }
  }
#else
  UNUSED_PARAMETER(pParse);
  UNUSED_PARAMETER(pBuilder);

  assert( pLower || pUpper );
#endif
  assert( pUpper==0 || (pUpper->wtFlags & TERM_VNULL)==0 );
  nNew = whereRangeAdjust(pLower, nOut);
  nNew = whereRangeAdjust(pUpper, nNew);

  /* TUNING: If there is both an upper and lower limit, assume the range is
  ** reduced by an additional 75%. This means that, by default, an open-ended
  ** range query (e.g. col > ?) is assumed to match 1/4 of the rows in the

do_test alter4-2.6 {
  catchsql {
    alter table t1 add column d DEFAULT CURRENT_TIME;
  }
} {1 {Cannot add a column with non-constant default}}
do_test alter4-2.7 {
  catchsql {
    alter table t1 add column d default (-+1);
  }
} {1 {Cannot add a column with non-constant default}}
do_test alter4-2.99 {
  execsql {
    DROP TABLE t1;
  }
} {}

do_test alter4-2.6 {
  catchsql {
    alter table t1 add column d DEFAULT CURRENT_TIME;
  }
} {1 {Cannot add a column with non-constant default}}
do_test alter4-2.7 {
  catchsql {
    alter table t1 add column d default (-5+1);
  }
} {1 {Cannot add a column with non-constant default}}
do_test alter4-2.99 {
  execsql {
    DROP TABLE t1;
  }
} {}

  2 "d=0 AND a='z' AND b='n' AND e<100" {/*t5e (e<?)*/}

  3 "d=0 AND e<300"                     {/*t5d (d=?)*/}
  4 "d=0 AND e<200"                     {/*t5e (e<?)*/}
} {
  do_eqp_test 24.$tn "SeLeCt * FROM t5 WHERE $where" $eqp
}















































finish_test

  2 "d=0 AND a='z' AND b='n' AND e<100" {/*t5e (e<?)*/}

  3 "d=0 AND e<300"                     {/*t5d (d=?)*/}
  4 "d=0 AND e<200"                     {/*t5e (e<?)*/}
} {
  do_eqp_test 24.$tn "SeLeCt * FROM t5 WHERE $where" $eqp
}

#-------------------------------------------------------------------------
# Test that if stat4 data is available but cannot be used because the
# rhs of a range constraint is a complex expression, the default estimates
# are used instead.
ifcapable stat4&&cte {
  do_execsql_test 25.1 {
    CREATE TABLE t6(a, b);
    WITH ints(i,j) AS (
      SELECT 1,1 UNION ALL SELECT i+1,j+1 FROM ints WHERE i<100
    ) INSERT INTO t6 SELECT * FROM ints;
    CREATE INDEX aa ON t6(a);
    CREATE INDEX bb ON t6(b);
    ANALYZE;
  }

  # Term (b<?) is estimated at 25%. Better than (a<30) but not as
  # good as (a<20).
  do_eqp_test 25.2.1 { SELECT * FROM t6 WHERE a<30 AND b<? } {
    0 0 0 {SEARCH TABLE t6 USING INDEX bb (b<?)}
  }
  do_eqp_test 25.2.2 { SELECT * FROM t6 WHERE a<20 AND b<? } {
    0 0 0 {SEARCH TABLE t6 USING INDEX aa (a<?)}
  }

  # Term (b BETWEEN ? AND ?) is estimated at 1/64.
  do_eqp_test 25.3.1 { 
    SELECT * FROM t6 WHERE a BETWEEN 5 AND 10 AND b BETWEEN ? AND ? 
  } {
    0 0 0 {SEARCH TABLE t6 USING INDEX bb (b>? AND b<?)}
  }
  
  # Term (b BETWEEN ? AND 60) is estimated to return roughly 15 rows -
  # 60 from (b<=60) multiplied by 0.25 for the b>=? term. Better than
  # (a<20) but not as good as (a<10).
  do_eqp_test 25.4.1 { 
    SELECT * FROM t6 WHERE a < 10 AND (b BETWEEN ? AND 60)
  } {
    0 0 0 {SEARCH TABLE t6 USING INDEX aa (a<?)}
  }
  do_eqp_test 25.4.2 { 
    SELECT * FROM t6 WHERE a < 20 AND (b BETWEEN ? AND 60)
  } {
    0 0 0 {SEARCH TABLE t6 USING INDEX bb (b>? AND b<?)}
  }
}

finish_test

foreach {tn analyze_cmd} {
  1 populate_stat4 
  2 populate_stat3
  3 populate_both
} {
  reset_db
  do_test 1.$tn.1 {
    execsql { CREATE TABLE t1(a INTEGER PRIMARY KEY, b, c) }
    for {set i 0} {$i < 100} {incr i} {
      set c [expr int(pow(1.1,$i)/100)]
      set b [expr 125 - int(pow(1.1,99-$i))/100]
      execsql {INSERT INTO t1 VALUES($i, $b, $c)}
    }
  } {}

................................................................................
  do_eqp_test 1.$tn.3.5 {
    SELECT * FROM t1 WHERE b BETWEEN 0 AND 50 AND c BETWEEN 0 AND 50
  } {0 0 0 {SEARCH TABLE t1 USING INDEX t1b (b>? AND b<?)}}

  do_eqp_test 1.$tn.3.6 {
    SELECT * FROM t1 WHERE b BETWEEN 75 AND 125 AND c BETWEEN 75 AND 125
  } {0 0 0 {SEARCH TABLE t1 USING INDEX t1c (c>? AND c<?)}}




















}

finish_test

foreach {tn analyze_cmd} {
  1 populate_stat4 
  2 populate_stat3
  3 populate_both
} {
  reset_db
  do_test 1.$tn.1 {
    execsql { CREATE TABLE t1(a INTEGER PRIMARY KEY, b INT, c INT) }
    for {set i 0} {$i < 100} {incr i} {
      set c [expr int(pow(1.1,$i)/100)]
      set b [expr 125 - int(pow(1.1,99-$i))/100]
      execsql {INSERT INTO t1 VALUES($i, $b, $c)}
    }
  } {}

................................................................................
  do_eqp_test 1.$tn.3.5 {
    SELECT * FROM t1 WHERE b BETWEEN 0 AND 50 AND c BETWEEN 0 AND 50
  } {0 0 0 {SEARCH TABLE t1 USING INDEX t1b (b>? AND b<?)}}

  do_eqp_test 1.$tn.3.6 {
    SELECT * FROM t1 WHERE b BETWEEN 75 AND 125 AND c BETWEEN 75 AND 125
  } {0 0 0 {SEARCH TABLE t1 USING INDEX t1c (c>? AND c<?)}}

  do_eqp_test 1.$tn.3.7 {
    SELECT * FROM t1 WHERE b BETWEEN +0 AND +50 AND c BETWEEN +0 AND +50
  } {0 0 0 {SEARCH TABLE t1 USING INDEX t1b (b>? AND b<?)}}

  do_eqp_test 1.$tn.3.8 {
    SELECT * FROM t1
     WHERE b BETWEEN cast('0' AS int) AND cast('50.0' AS real)
       AND c BETWEEN cast('0' AS numeric) AND cast('50.0' AS real)
  } {0 0 0 {SEARCH TABLE t1 USING INDEX t1b (b>? AND b<?)}}

  do_eqp_test 1.$tn.3.9 {
    SELECT * FROM t1 WHERE b BETWEEN +75 AND +125 AND c BETWEEN +75 AND +125
  } {0 0 0 {SEARCH TABLE t1 USING INDEX t1c (c>? AND c<?)}}

  do_eqp_test 1.$tn.3.10 {
    SELECT * FROM t1
     WHERE b BETWEEN cast('75' AS int) AND cast('125.0' AS real)
       AND c BETWEEN cast('75' AS numeric) AND cast('125.0' AS real)
  } {0 0 0 {SEARCH TABLE t1 USING INDEX t1c (c>? AND c<?)}}
}

finish_test

do_execsql_test 1.22 {
  SELECT next_char('AB','vocab2','w',null,'NOCASE');
} {cDeF}
do_execsql_test 1.23 {
  SELECT next_char('ab','vocab2','w',null,'binary');
} {c}

















do_execsql_test 2.1 {
  CREATE VIRTUAL TABLE t2 USING spellfix1;
  INSERT INTO t2 (word, soundslike) VALUES('school', 'skuul');
  INSERT INTO t2 (word, soundslike) VALUES('psalm', 'sarm');
  SELECT word, matchlen FROM t2 WHERE word MATCH 'sar*' LIMIT 5;
} {psalm 4}

do_execsql_test 1.22 {
  SELECT next_char('AB','vocab2','w',null,'NOCASE');
} {cDeF}
do_execsql_test 1.23 {
  SELECT next_char('ab','vocab2','w',null,'binary');
} {c}

do_execsql_test 1.30 {
  SELECT rowid FROM t1 WHERE word='rabbit';
} {2}
do_execsql_test 1.31 {
  UPDATE t1 SET rowid=2000 WHERE word='rabbit';
  SELECT rowid FROM t1 WHERE word='rabbit';
} {2000}
do_execsql_test 1.32 {
  INSERT INTO t1(rowid, word) VALUES(3000,'melody');
  SELECT rowid, word, matchlen FROM t1 WHERE word MATCH 'melotti'
   ORDER BY score LIMIT 3;
} {3000 melody 6}
do_test 1.33 {
  catchsql {INSERT INTO t1(rowid, word) VALUES(3000,'garden');}
} {1 {constraint failed}}

do_execsql_test 2.1 {
  CREATE VIRTUAL TABLE t2 USING spellfix1;
  INSERT INTO t2 (word, soundslike) VALUES('school', 'skuul');
  INSERT INTO t2 (word, soundslike) VALUES('psalm', 'sarm');
  SELECT word, matchlen FROM t2 WHERE word MATCH 'sar*' LIMIT 5;
} {psalm 4}