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Overview
Comment:Additional ".selecttrace" debugging output when the query is transformed from a DISTINCT into a GROUP BY.
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SHA1: 5a46914510af4d5557b299db65c68d5df1070766
User & Date: drh 2016-04-14 13:06:49.646
Context
2016-04-14
13:16
Since the return value of sqlite3OsClose() is always ignored, we might as well make it "void" instead of "int", and thereby save 50 bytes in the compiled binary. (check-in: 7ee570e7a9 user: drh tags: trunk)
13:06
Additional ".selecttrace" debugging output when the query is transformed from a DISTINCT into a GROUP BY. (check-in: 5a46914510 user: drh tags: trunk)
2016-04-13
21:00
Fix compiler warnings by removing surplus local variables in the schema pretty-printer logic of the command-line shell. (check-in: 55a62483b9 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/select.c.
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  ){
    p->selFlags &= ~SF_Distinct;
    pGroupBy = p->pGroupBy = sqlite3ExprListDup(db, pEList, 0);
    /* Notice that even thought SF_Distinct has been cleared from p->selFlags,
    ** the sDistinct.isTnct is still set.  Hence, isTnct represents the
    ** original setting of the SF_Distinct flag, not the current setting */
    assert( sDistinct.isTnct );







  }

  /* If there is an ORDER BY clause, then create an ephemeral index to
  ** do the sorting.  But this sorting ephemeral index might end up
  ** being unused if the data can be extracted in pre-sorted order.
  ** If that is the case, then the OP_OpenEphemeral instruction will be
  ** changed to an OP_Noop once we figure out that the sorting index is







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  ){
    p->selFlags &= ~SF_Distinct;
    pGroupBy = p->pGroupBy = sqlite3ExprListDup(db, pEList, 0);
    /* Notice that even thought SF_Distinct has been cleared from p->selFlags,
    ** the sDistinct.isTnct is still set.  Hence, isTnct represents the
    ** original setting of the SF_Distinct flag, not the current setting */
    assert( sDistinct.isTnct );

#if SELECTTRACE_ENABLED
    if( sqlite3SelectTrace & 0x400 ){
      SELECTTRACE(0x400,pParse,p,("Transform DISTINCT into GROUP BY:\n"));
      sqlite3TreeViewSelect(0, p, 0);
    }
#endif
  }

  /* If there is an ORDER BY clause, then create an ephemeral index to
  ** do the sorting.  But this sorting ephemeral index might end up
  ** being unused if the data can be extracted in pre-sorted order.
  ** If that is the case, then the OP_OpenEphemeral instruction will be
  ** changed to an OP_Noop once we figure out that the sorting index is