** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btree.c,v 1.54 2002/02/19 15:00:07 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.
................................................................................
    if( rc ) return rc;
  }
  return SQLITE_OK;
}

/* Move the cursor to the first entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty and there is no first element.
*/
int sqliteBtreeFirst(BtCursor *pCur, int *pRes){
  int rc;
  if( pCur->pPage==0 ) return SQLITE_ABORT;
  rc = moveToRoot(pCur);
  if( rc ) return rc;
  if( pCur->pPage->nCell==0 ){
................................................................................
  rc = moveToLeftmost(pCur);
  pCur->bSkipNext = 0;
  return rc;
}

/* Move the cursor to the last entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty and there is no first element.
*/
int sqliteBtreeLast(BtCursor *pCur, int *pRes){
  int rc;
  Pgno pgno;
  if( pCur->pPage==0 ) return SQLITE_ABORT;
  rc = moveToRoot(pCur);
  if( rc ) return rc;

** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** $Id: btree.c,v 1.55 2002/02/19 22:43:59 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.
................................................................................
    if( rc ) return rc;
  }
  return SQLITE_OK;
}

/* Move the cursor to the first entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
int sqliteBtreeFirst(BtCursor *pCur, int *pRes){
  int rc;
  if( pCur->pPage==0 ) return SQLITE_ABORT;
  rc = moveToRoot(pCur);
  if( rc ) return rc;
  if( pCur->pPage->nCell==0 ){
................................................................................
  rc = moveToLeftmost(pCur);
  pCur->bSkipNext = 0;
  return rc;
}

/* Move the cursor to the last entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
int sqliteBtreeLast(BtCursor *pCur, int *pRes){
  int rc;
  Pgno pgno;
  if( pCur->pPage==0 ) return SQLITE_ABORT;
  rc = moveToRoot(pCur);
  if( rc ) return rc;