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Check-in [8e5cfb2039]
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Overview
Comment:B-tree optimization: When seeking on a rowid table that has already been positioned, check to see if the new row happens to be the next row on the same leaf page. That is a reasonably common case, and if it is true it avoids a full binary search.
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Timelines: family | ancestors | descendants | both | btree-moveto-neighbor
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SHA1: 8e5cfb2039126da7689c4b1c88760f10e1234eaf
User & Date: drh 2017-01-21 16:54:19.338
Context
2017-01-21
21:47
A better implementation of the moveto-neighbor optimization that checks for nearby rows on adjacent pages. (Closed-Leaf check-in: 2c4ecb85a4 user: drh tags: btree-moveto-neighbor)
16:54
B-tree optimization: When seeking on a rowid table that has already been positioned, check to see if the new row happens to be the next row on the same leaf page. That is a reasonably common case, and if it is true it avoids a full binary search. (check-in: 8e5cfb2039 user: drh tags: btree-moveto-neighbor)
16:27
Change sqlite3_blob_reopen() to call sqlite3VdbeExec() directly rather than going through sqlite3_step(). Performance enhancement. (check-in: 347df3c1fd user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/btree.c.
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  if( pIdxKey==0
   && pCur->eState==CURSOR_VALID && (pCur->curFlags & BTCF_ValidNKey)!=0
  ){
    if( pCur->info.nKey==intKey ){
      *pRes = 0;
      return SQLITE_OK;
    }

    if( (pCur->curFlags & BTCF_AtLast)!=0 && pCur->info.nKey<intKey ){
      *pRes = -1;
      return SQLITE_OK;











    }
  }

  if( pIdxKey ){
    xRecordCompare = sqlite3VdbeFindCompare(pIdxKey);
    pIdxKey->errCode = 0;
    assert( pIdxKey->default_rc==1 








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  if( pIdxKey==0
   && pCur->eState==CURSOR_VALID && (pCur->curFlags & BTCF_ValidNKey)!=0
  ){
    if( pCur->info.nKey==intKey ){
      *pRes = 0;
      return SQLITE_OK;
    }
    if( pCur->info.nKey<intKey ){
      if( (pCur->curFlags & BTCF_AtLast)!=0 ){
        *pRes = -1;
        return SQLITE_OK;
      }
      if( pCur->aiIdx[pCur->iPage]+1<pCur->apPage[pCur->iPage]->nCell ){
        pCur->aiIdx[pCur->iPage]++;
        pCur->info.nSize = 0;
        pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
        getCellInfo(pCur);
        if( pCur->info.nKey==intKey ){
          *pRes = 0;
          return SQLITE_OK;
        }
      }
    }
  }

  if( pIdxKey ){
    xRecordCompare = sqlite3VdbeFindCompare(pIdxKey);
    pIdxKey->errCode = 0;
    assert( pIdxKey->default_rc==1
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