SQLite

    */
    zeroPage(pPage, PTF_INTKEY|PTF_LEAF );
    releasePage(pPage);
  }
  return rc;  
}
int sqlite3BtreeDropTable(Btree *p, int iTable, int *piMoved){
  BtShared *pBt = p->pBt;
  int rc;
  sqlite3BtreeEnter(p);
  rc = btreeDropTable(p, iTable, piMoved);
  sqlite3BtreeLeave(p);
  return rc;
}

  u8 fullSync;                /* Do extra syncs of the journal for robustness */
  u8 ckptSyncFlags;           /* SYNC_NORMAL or SYNC_FULL for checkpoint */
  u8 syncFlags;               /* SYNC_NORMAL or SYNC_FULL otherwise */
  u8 tempFile;                /* zFilename is a temporary file */
  u8 readOnly;                /* True for a read-only database */
  u8 memDb;                   /* True to inhibit all file I/O */
  u8 hasSeenStress;           /* pagerStress() called one or more times */
  u8 isSorter;                /* True for a PAGER_SORTER */

  /**************************************************************************
  ** The following block contains those class members that change during
  ** routine opertion.  Class members not in this block are either fixed
  ** when the pager is first created or else only change when there is a
  ** significant mode change (such as changing the page_size, locking_mode,
  ** or the journal_mode).  From another view, these class members describe

    assert( p->journalMode==PAGER_JOURNALMODE_OFF 
         || p->journalMode==PAGER_JOURNALMODE_MEMORY 
    );
    assert( p->eState!=PAGER_ERROR && p->eState!=PAGER_OPEN );
    assert( pagerUseWal(p)==0 );
  }

  /* A sorter is a temp file that never spills to disk and always has
  ** the doNotSpill flag set
  */
  if( p->isSorter ){
    assert( p->tempFile );
    assert( p->doNotSpill );
    assert( p->fd->pMethods==0 );
  }

  /* If changeCountDone is set, a RESERVED lock or greater must be held
  ** on the file.
  */
  assert( pPager->changeCountDone==0 || pPager->eLock>=RESERVED_LOCK );
  assert( p->eLock!=PENDING_LOCK );

  switch( p->eState ){

  }else if( memDb ){
    pPager->journalMode = PAGER_JOURNALMODE_MEMORY;
  }
  /* pPager->xBusyHandler = 0; */
  /* pPager->pBusyHandlerArg = 0; */
  pPager->xReiniter = xReinit;
  /* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */
#ifndef SQLITE_OMIT_MERGE_SORT
  if( flags & PAGER_SORTER ){
    pPager->doNotSpill = 1;
    pPager->isSorter = 1;
  }
#endif

  *ppPager = pPager;
  return SQLITE_OK;
}

/*
** Return true if this is an in-memory pager.
*/
int sqlite3PagerIsMemdb(Pager *pPager){
  return MEMDB;
}

#ifndef SQLITE_OMIT_MERGE_SORT
/*
** Return true if the pager has seen a pagerStress callback.
*/
int sqlite3PagerUnderStress(Pager *pPager){
  assert( pPager->isSorter );
  assert( pPager->doNotSpill );
  return pPager->hasSeenStress;
}
#endif

/*
** Check that there are at least nSavepoint savepoints open. If there are
** currently less than nSavepoints open, then open one or more savepoints
** to make up the difference. If the number of savepoints is already
** equal to nSavepoint, then this function is a no-op.
**
** If a memory allocation fails, SQLITE_NOMEM is returned. If an error 

const char *sqlite3PagerFilename(Pager*);
const sqlite3_vfs *sqlite3PagerVfs(Pager*);
sqlite3_file *sqlite3PagerFile(Pager*);
const char *sqlite3PagerJournalname(Pager*);
int sqlite3PagerNosync(Pager*);
void *sqlite3PagerTempSpace(Pager*);
int sqlite3PagerIsMemdb(Pager*);
#ifndef SQLITE_OMIT_MERGE_SORT
int sqlite3PagerUnderStress(Pager*);
#endif

/* Functions used to truncate the database file. */
void sqlite3PagerTruncateImage(Pager*,Pgno);

#if defined(SQLITE_HAS_CODEC) && !defined(SQLITE_OMIT_WAL)
void *sqlite3PagerCodec(DbPage *);
#endif

  VdbeSorterIter *aIter;          /* Array of iterators to merge */
  int *aTree;                     /* Current state of incremental merge */
  i64 iWriteOff;                  /* Current write offset within file pTemp1 */
  i64 iReadOff;                   /* Current read offset within file pTemp1 */
  sqlite3_file *pTemp1;           /* PMA file 1 */
  int nPMA;                       /* Number of PMAs stored in pTemp1 */
  SorterRecord *pRecord;          /* Head of in-memory record list */
  int nLimit1;                    /* Minimum PMA size, in bytes */
  int nLimit2;                    /* Maximum PMA size, in bytes */
  char *aSpace;                   /* Space for UnpackRecord() */
  int nSpace;                     /* Size of aSpace in bytes */
};

/*
** The following type is an iterator for a PMA. It caches the current key in 
** variables nKey/aKey. If the iterator is at EOF, pFile==0.

}

/*
** Initialize the temporary index cursor just opened as a sorter cursor.
*/
int sqlite3VdbeSorterInit(sqlite3 *db, VdbeCursor *pCsr){
  int pgsz;                       /* Page size of main database */



  assert( pCsr->pKeyInfo && pCsr->pBt==0 );
  pCsr->pSorter = sqlite3DbMallocZero(db, sizeof(VdbeSorter));
  if( pCsr->pSorter==0 ){
    return SQLITE_NOMEM;
  }

  pgsz = sqlite3BtreeGetPageSize(db->aDb[0].pBt);
  pCsr->pSorter->nLimit1 = 10 * pgsz;
  pCsr->pSorter->nLimit2 = db->aDb[0].pSchema->cache_size * pgsz;



  return SQLITE_OK;
}

/*
** Free the list of sorted records starting at pRecord.
*/

      rc = vdbeSorterMerge(db, pCsr, p, aSlot[i], &p);
    }else{
      vdbeSorterRecordFree(db, aSlot[i]);
    }
  }
  pSorter->pRecord = p;

#if 0
  {
    SorterRecord *pTmp1 = 0;
    SorterRecord *pTmp2;
    for(pTmp2=pSorter->pRecord; pTmp2 && rc==SQLITE_OK; pTmp2=pTmp2->pNext){
      if( pTmp1 ){
        int res;
        rc = vdbeSorterCompare(pCsr, 
            0, pTmp1->pVal, pTmp1->nVal, pTmp2->pVal, pTmp2->nVal, &res
        );
        assert( rc!=SQLITE_OK || res<0 );
      }
      pTmp1 = pTmp2;
    }
  }
#endif

  if( rc!=SQLITE_OK ){
  }
  sqlite3_free(aSlot);
  return rc;
}


/*
** Write the current contents of the in-memory linked-list to a PMA. Return

  **   * The total memory allocated for the in-memory list is greater 
  **     than (page-size * cache-size), or
  **
  **   * The total memory allocated for the in-memory list is greater 
  **     than (page-size * 10) and sqlite3HeapNearlyFull() returns true.
  */
  if( rc==SQLITE_OK && (
        (pSorter->nInMemory>pSorter->nLimit2)
     || (pSorter->nInMemory>pSorter->nLimit1 && sqlite3HeapNearlyFull())
  )){
    rc = vdbeSorterListToPMA(db, pCsr);
    pSorter->nInMemory = 0;
  }

  return rc;
}

){
  int rc;
  VdbeSorter *pSorter = pCsr->pSorter;
  void *pKey; int nKey;           /* Sorter key to compare pVal with */

  pKey = vdbeSorterRowkey(pSorter, &nKey);
  rc = vdbeSorterCompare(pCsr, 1, pVal->z, pVal->n, pKey, nKey, pRes);
  assert( rc!=SQLITE_OK || *pRes<=0 );
  return rc;
}

#endif /* #ifndef SQLITE_OMIT_MERGE_SORT */