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Changes to src/where.c.

  5467   5467     WherePath *aTo;           /* The nTo best paths at the current level */
  5468   5468     WherePath *pFrom;         /* An element of aFrom[] that we are working on */
  5469   5469     WherePath *pTo;           /* An element of aTo[] that we are working on */
  5470   5470     WhereLoop *pWLoop;        /* One of the WhereLoop objects */
  5471   5471     WhereLoop **pX;           /* Used to divy up the pSpace memory */
  5472   5472     LogEst *aSortCost = 0;    /* Sorting and partial sorting costs */
  5473   5473     char *pSpace;             /* Temporary memory used by this routine */
         5474  +  int nSpace;               /* Bytes of space allocated at pSpace */
  5474   5475   
  5475   5476     pParse = pWInfo->pParse;
  5476   5477     db = pParse->db;
  5477   5478     nLoop = pWInfo->nLevel;
  5478   5479     /* TUNING: For simple queries, only the best path is tracked.
  5479   5480     ** For 2-way joins, the 5 best paths are followed.
  5480   5481     ** For joins of 3 or more tables, track the 10 best paths */
................................................................................
  5490   5491     if( pWInfo->pOrderBy==0 || nRowEst==0 ){
  5491   5492       nOrderBy = 0;
  5492   5493     }else{
  5493   5494       nOrderBy = pWInfo->pOrderBy->nExpr;
  5494   5495     }
  5495   5496   
  5496   5497     /* Allocate and initialize space for aTo, aFrom and aSortCost[] */
  5497         -  ii = (sizeof(WherePath)+sizeof(WhereLoop*)*nLoop)*mxChoice*2;
  5498         -  ii += sizeof(LogEst) * nOrderBy;
  5499         -  pSpace = sqlite3DbMallocRaw(db, ii);
         5498  +  nSpace = (sizeof(WherePath)+sizeof(WhereLoop*)*nLoop)*mxChoice*2;
         5499  +  nSpace += sizeof(LogEst) * nOrderBy;
         5500  +  pSpace = sqlite3DbMallocRaw(db, nSpace);
  5500   5501     if( pSpace==0 ) return SQLITE_NOMEM;
  5501   5502     aTo = (WherePath*)pSpace;
  5502   5503     aFrom = aTo+mxChoice;
  5503   5504     memset(aFrom, 0, sizeof(aFrom[0]));
  5504   5505     pX = (WhereLoop**)(aFrom+mxChoice);
  5505   5506     for(ii=mxChoice*2, pFrom=aTo; ii>0; ii--, pFrom++, pX += nLoop){
  5506   5507       pFrom->aLoop = pX;
................................................................................
  5509   5510       /* If there is an ORDER BY clause and it is not being ignored, set up
  5510   5511       ** space for the aSortCost[] array. Each element of the aSortCost array
  5511   5512       ** is either zero - meaning it has not yet been initialized - or the
  5512   5513       ** cost of sorting nRowEst rows of data where the first X terms of
  5513   5514       ** the ORDER BY clause are already in order, where X is the array 
  5514   5515       ** index.  */
  5515   5516       aSortCost = (LogEst*)pX;
  5516         -    memset(aSortCost, 0, sizeof(LogEst) * (nOrderBy+1));
         5517  +    memset(aSortCost, 0, sizeof(LogEst) * nOrderBy);
  5517   5518     }
         5519  +  assert( aSortCost==0 || &pSpace[nSpace]==(char*)&aSortCost[nOrderBy] );
         5520  +  assert( aSortCost!=0 || &pSpace[nSpace]==(char*)pX );
  5518   5521   
  5519   5522     /* Seed the search with a single WherePath containing zero WhereLoops.
  5520   5523     **
  5521   5524     ** TUNING: Do not let the number of iterations go above 25.  If the cost
  5522   5525     ** of computing an automatic index is not paid back within the first 25
  5523   5526     ** rows, then do not use the automatic index. */
  5524   5527     aFrom[0].nRow = MIN(pParse->nQueryLoop, 46);  assert( 46==sqlite3LogEst(25) );