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Overview
Comment:More efficient removal of duplicates in recursive queries using the UNION compound operator.
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SHA1: 06c2db875e6cabd81c2a153b2fa4aba03eaed268
User & Date: drh 2014-02-26 21:35:31.484
Context
2014-02-27
15:04
Add #defines to the command-line shell source code (shell.c) so that it can be imported directly into other projects (ex: Fossil) and used without editing. (check-in: a669040023 user: drh tags: trunk)
05:47
Merge updates from trunk. (check-in: ed0bfcfadc user: mistachkin tags: winIoRetry)
2014-02-26
21:35
More efficient removal of duplicates in recursive queries using the UNION compound operator. (check-in: 06c2db875e user: drh tags: trunk)
13:53
In the command-line shell for CSV import, if the lines are \r\n terminated and the last field is blank, make sure an empty string and not a "\r" string is imported. (check-in: 9c2e7612cd user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/select.c.
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      ExprList *pSO;
      pSO = pDest->pOrderBy;
      assert( pSO );
      nKey = pSO->nExpr;
      r1 = sqlite3GetTempReg(pParse);
      r2 = sqlite3GetTempRange(pParse, nKey+2);
      r3 = r2+nKey+1;
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nResultCol, r3);
      if( eDest==SRT_DistQueue ){
        /* If the destination is DistQueue, then cursor (iParm+1) is open
        ** on a second ephemeral index that holds all values every previously
        ** added to the queue.  Only add this new value if it has never before
        ** been added */
        addrTest = sqlite3VdbeAddOp4Int(v, OP_Found, iParm+1, 0, r3, 0);

        VdbeCoverage(v);



        sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm+1, r3);
        sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
      }
      for(i=0; i<nKey; i++){
        sqlite3VdbeAddOp2(v, OP_SCopy,
                          regResult + pSO->a[i].u.x.iOrderByCol - 1,
                          r2+i);








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814
815
816
817
818
819
820

821
822
823
824

825
826
827
828
829
830
831
832
833
834
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      ExprList *pSO;
      pSO = pDest->pOrderBy;
      assert( pSO );
      nKey = pSO->nExpr;
      r1 = sqlite3GetTempReg(pParse);
      r2 = sqlite3GetTempRange(pParse, nKey+2);
      r3 = r2+nKey+1;

      if( eDest==SRT_DistQueue ){
        /* If the destination is DistQueue, then cursor (iParm+1) is open
        ** on a second ephemeral index that holds all values every previously
        ** added to the queue. */

        addrTest = sqlite3VdbeAddOp4Int(v, OP_Found, iParm+1, 0, 
                                        regResult, nResultCol);
        VdbeCoverage(v);
      }
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nResultCol, r3);
      if( eDest==SRT_DistQueue ){
        sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm+1, r3);
        sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
      }
      for(i=0; i<nKey; i++){
        sqlite3VdbeAddOp2(v, OP_SCopy,
                          regResult + pSO->a[i].u.x.iOrderByCol - 1,
                          r2+i);
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