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SQLite training in Houston TX on 2019-11-05 (details)
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Overview
Comment:Sorting is now done using a sorting index rather than loading the entire result set into memory and doing a merge sort. The old merge sort technique was a carry-over from SQLite version 1. The new method uses a bounded amount of memory and scales to much larger result sets. There are still errors: some 39 regression tests fail. (CVS 2653)
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Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 09db0a24241f9248584250d1728117b8a3159626
User & Date: drh 2005-09-01 03:07:44
Context
2005-09-01
12:16
All regression tests now pass with the new bounded-memory sort code. There is still lots of opportunity for optimization, however. (CVS 2654) check-in: 81259a01 user: drh tags: trunk
03:07
Sorting is now done using a sorting index rather than loading the entire result set into memory and doing a merge sort. The old merge sort technique was a carry-over from SQLite version 1. The new method uses a bounded amount of memory and scales to much larger result sets. There are still errors: some 39 regression tests fail. (CVS 2653) check-in: 09db0a24 user: drh tags: trunk
2005-08-31
18:20
{quote: KeyInfo} generation moved to a common subroutine. (CVS 2652) check-in: a25801df user: drh tags: trunk
Changes
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Changes to src/expr.c.

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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.222 2005/08/30 00:54:02 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**
................................................................................
  pNew->pOrderBy = sqlite3ExprListDup(p->pOrderBy);
  pNew->op = p->op;
  pNew->pPrior = sqlite3SelectDup(p->pPrior);
  pNew->pLimit = sqlite3ExprDup(p->pLimit);
  pNew->pOffset = sqlite3ExprDup(p->pOffset);
  pNew->iLimit = -1;
  pNew->iOffset = -1;
  pNew->ppOpenVirtual = 0;
  pNew->isResolved = p->isResolved;
  pNew->isAgg = p->isAgg;




  return pNew;
}
#else
Select *sqlite3SelectDup(Select *p){
  assert( p==0 );
  return 0;
}







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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.223 2005/09/01 03:07:44 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**
................................................................................
  pNew->pOrderBy = sqlite3ExprListDup(p->pOrderBy);
  pNew->op = p->op;
  pNew->pPrior = sqlite3SelectDup(p->pPrior);
  pNew->pLimit = sqlite3ExprDup(p->pLimit);
  pNew->pOffset = sqlite3ExprDup(p->pOffset);
  pNew->iLimit = -1;
  pNew->iOffset = -1;

  pNew->isResolved = p->isResolved;
  pNew->isAgg = p->isAgg;
  pNew->pRightmost = 0;
  pNew->addrOpenVirt[0] = -1;
  pNew->addrOpenVirt[1] = -1;
  pNew->addrOpenVirt[2] = -1;
  return pNew;
}
#else
Select *sqlite3SelectDup(Select *p){
  assert( p==0 );
  return 0;
}

Changes to src/select.c.

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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.257 2005/08/31 18:20:00 drh Exp $
*/
#include "sqliteInt.h"


/*
** Allocate a new Select structure and return a pointer to that
** structure.
................................................................................
    pNew->pOrderBy = pOrderBy;
    pNew->isDistinct = isDistinct;
    pNew->op = TK_SELECT;
    pNew->pLimit = pLimit;
    pNew->pOffset = pOffset;
    pNew->iLimit = -1;
    pNew->iOffset = -1;



  }
  return pNew;
}

/*
** Given 1 to 3 identifiers preceeding the JOIN keyword, determine the
** type of join.  Return an integer constant that expresses that type
................................................................................

/*
** Insert code into "v" that will push the record on the top of the
** stack into the sorter.
*/
static void pushOntoSorter(Parse *pParse, Vdbe *v, ExprList *pOrderBy){
  sqlite3ExprCodeExprList(pParse, pOrderBy);

  sqlite3VdbeAddOp(v, OP_MakeRecord, pOrderBy->nExpr, 0);
  sqlite3VdbeAddOp(v, OP_SortInsert, 0, 0);
}

/*
** Add code to implement the OFFSET and LIMIT
*/
static void codeLimiter(
  Vdbe *v,          /* Generate code into this VM */
................................................................................
  }
  return 0;
}

/*
** Given an expression list, generate a KeyInfo structure that records
** the collating sequence for each expression in that expression list.






**
** Space to hold the KeyInfo structure is obtain from malloc.  The calling
** function is responsible for seeing that this structure is eventually
** freed.  Add the KeyInfo structure to the P3 field of an opcode using
** P3_KEYINFO_HANDOFF is the usual way of dealing with this.
*/
static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList){
................................................................................
  Parse *pParse,   /* The parsing context */
  Select *p,       /* The SELECT statement */
  Vdbe *v,         /* Generate code into this VDBE */
  int nColumn,     /* Number of columns of data */
  int eDest,       /* Write the sorted results here */
  int iParm        /* Optional parameter associated with eDest */
){
  int end1 = sqlite3VdbeMakeLabel(v);
  int end2 = sqlite3VdbeMakeLabel(v);
  int addr;
  KeyInfo *pInfo;


  if( eDest==SRT_Sorter ) return;
  pInfo = keyInfoFromExprList(pParse, p->pOrderBy);
  if( pInfo==0 ) return;
  sqlite3VdbeOp3(v, OP_Sort, 0, 0, (char*)pInfo, P3_KEYINFO_HANDOFF);
  addr = sqlite3VdbeAddOp(v, OP_SortNext, 0, end1);
  codeLimiter(v, p, addr, end2, 1);

  switch( eDest ){
    case SRT_Table:
    case SRT_TempTable: {
      sqlite3VdbeAddOp(v, OP_NewRowid, iParm, 0);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      sqlite3VdbeAddOp(v, OP_Insert, iParm, 0);
      break;
................................................................................
      sqlite3VdbeAddOp(v, OP_IdxInsert, (iParm&0x0000FFFF), 0);
      break;
    }
    case SRT_Exists:
    case SRT_Mem: {
      assert( nColumn==1 );
      sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
      sqlite3VdbeAddOp(v, OP_Goto, 0, end1);
      break;
    }
#endif
    case SRT_Callback:
    case SRT_Subroutine: {
      int i;
      sqlite3VdbeAddOp(v, OP_Integer, p->pEList->nExpr, 0);
................................................................................
      break;
    }
    default: {
      /* Do nothing */
      break;
    }
  }
  sqlite3VdbeAddOp(v, OP_Goto, 0, addr);
  sqlite3VdbeResolveLabel(v, end2);
  sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
  sqlite3VdbeResolveLabel(v, end1);
  sqlite3VdbeAddOp(v, OP_SortReset, 0, 0);
}

/*
** Return a pointer to a string containing the 'declaration type' of the
** expression pExpr. The string may be treated as static by the caller.
**
** If the declaration type is the exact datatype definition extracted from
................................................................................
    sqlite3VdbeAddOp(v, OP_MemStore, iMem, 1);
    VdbeComment((v, "# OFFSET counter"));
    p->iOffset = iMem;
  }
}

/*
** Generate VDBE instructions that will open a transient table that
** will be used for an index or to store keyed results for a compound
** select.  In other words, open a transient table that needs a
** KeyInfo structure.  The number of columns in the KeyInfo is determined
** by the result set of the SELECT statement in the second argument.
**
** Specifically, this routine is called to open an index table for
** DISTINCT, UNION, INTERSECT and EXCEPT select statements (but not 
** UNION ALL).
**
** The value returned is the address of the OP_OpenVirtual instruction.
*/
static int openVirtualIndex(Parse *pParse, Select *p, int iTab){
  KeyInfo *pKeyInfo;
  Vdbe *v = pParse->pVdbe;

  int addr;







  if( prepSelectStmt(pParse, p) ){
    return 0;
  }
  pKeyInfo = keyInfoFromExprList(pParse, p->pEList);
  if( pKeyInfo==0 ) return 0;
  addr = sqlite3VdbeOp3(v, OP_OpenVirtual, iTab, 0, 
                        (char*)pKeyInfo, P3_KEYINFO_HANDOFF);
  return addr;
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Add the address "addr" to the set of all OpenVirtual opcode addresses
** that are being accumulated in p->ppOpenVirtual.
*/
static int multiSelectOpenVirtualAddr(Select *p, int addr){
  IdList *pList = *p->ppOpenVirtual = sqlite3IdListAppend(*p->ppOpenVirtual, 0);
  if( pList==0 ){
    return SQLITE_NOMEM;
  }
  pList->a[pList->nId-1].idx = addr;
  return SQLITE_OK;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Return the appropriate collating sequence for the iCol-th column of
** the result set for the compound-select statement "p".  Return NULL if
** the column has no default collating sequence.
**
** The collating sequence for the compound select is taken from the
................................................................................
  int eDest,            /* \___  Store query results as specified */
  int iParm,            /* /     by these two parameters.         */
  char *aff             /* If eDest is SRT_Union, the affinity string */
){
  int rc = SQLITE_OK;   /* Success code from a subroutine */
  Select *pPrior;       /* Another SELECT immediately to our left */
  Vdbe *v;              /* Generate code to this VDBE */
  IdList *pOpenVirtual = 0;/* OP_OpenVirtual opcodes that need a KeyInfo */
  int aAddr[5];         /* Addresses of SetNumColumns operators */
  int nAddr = 0;        /* Number used */
  int nCol;             /* Number of columns in the result set */




  /* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs.  Only
  ** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
  */
  if( p==0 || p->pPrior==0 ){
    rc = 1;
    goto multi_select_end;
  }
  pPrior = p->pPrior;


  if( pPrior->pOrderBy ){
    sqlite3ErrorMsg(pParse,"ORDER BY clause should come after %s not before",
      selectOpName(p->op));
    rc = 1;
    goto multi_select_end;
  }
  if( pPrior->pLimit ){
................................................................................
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    rc = 1;
    goto multi_select_end;
  }

  /* If *p this is the right-most select statement, then initialize
  ** p->ppOpenVirtual to point to pOpenVirtual.  If *p is not the right most
  ** statement then p->ppOpenVirtual will have already been initialized
  ** by a prior call to this same procedure.  Pass along the pOpenVirtual
  ** pointer to pPrior, the next statement to our left.
  */
  if( p->ppOpenVirtual==0 ){
    p->ppOpenVirtual = &pOpenVirtual;
  }
  pPrior->ppOpenVirtual = p->ppOpenVirtual;

  /* Create the destination temporary table if necessary
  */
  if( eDest==SRT_TempTable ){
    assert( p->pEList );
    sqlite3VdbeAddOp(v, OP_OpenVirtual, iParm, 0);
    assert( nAddr==0 );
    aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, iParm, 0);
    eDest = SRT_Table;
  }

  /* Generate code for the left and right SELECT statements.
  */

  switch( p->op ){
    case TK_ALL: {
      if( p->pOrderBy==0 ){
        assert( !pPrior->pLimit );
        pPrior->pLimit = p->pLimit;
        pPrior->pOffset = p->pOffset;
        rc = sqlite3Select(pParse, pPrior, eDest, iParm, 0, 0, 0, aff);
        if( rc ){
          goto multi_select_end;
        }
................................................................................
    }
    case TK_EXCEPT:
    case TK_UNION: {
      int unionTab;    /* Cursor number of the temporary table holding result */
      int op = 0;      /* One of the SRT_ operations to apply to self */
      int priorOp;     /* The SRT_ operation to apply to prior selects */
      Expr *pLimit, *pOffset; /* Saved values of p->nLimit and p->nOffset */
      ExprList *pOrderBy;     /* The ORDER BY clause for the right SELECT */
      int addr;

      priorOp = p->op==TK_ALL ? SRT_Table : SRT_Union;
      if( eDest==priorOp && p->pOrderBy==0 && !p->pLimit && !p->pOffset ){
        /* We can reuse a temporary table generated by a SELECT to our
        ** right.
        */
        unionTab = iParm;
      }else{
        /* We will need to create our own temporary table to hold the
        ** intermediate results.
        */
        unionTab = pParse->nTab++;
        if( p->pOrderBy 
        && matchOrderbyToColumn(pParse, p, p->pOrderBy, unionTab, 1) ){
          rc = 1;
          goto multi_select_end;
        }
        addr = sqlite3VdbeAddOp(v, OP_OpenVirtual, unionTab, 0);
        if( p->op!=TK_ALL ){
          rc = multiSelectOpenVirtualAddr(p, addr);
          if( rc!=SQLITE_OK ){
            goto multi_select_end;
          }
        }
	assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
        aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, unionTab, 0);

        assert( p->pEList );
      }

      /* Code the SELECT statements to our left
      */
      assert( !pPrior->pOrderBy );
      rc = sqlite3Select(pParse, pPrior, priorOp, unionTab, 0, 0, 0, aff);
................................................................................
      */
      switch( p->op ){
         case TK_EXCEPT:  op = SRT_Except;   break;
         case TK_UNION:   op = SRT_Union;    break;
         case TK_ALL:     op = SRT_Table;    break;
      }
      p->pPrior = 0;
      pOrderBy = p->pOrderBy;
      p->pOrderBy = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      rc = sqlite3Select(pParse, p, op, unionTab, 0, 0, 0, aff);
      p->pPrior = pPrior;
................................................................................
        }
        iBreak = sqlite3VdbeMakeLabel(v);
        iCont = sqlite3VdbeMakeLabel(v);
        sqlite3VdbeAddOp(v, OP_Rewind, unionTab, iBreak);
        computeLimitRegisters(pParse, p);
        iStart = sqlite3VdbeCurrentAddr(v);
        rc = selectInnerLoop(pParse, p, p->pEList, unionTab, p->pEList->nExpr,
                             p->pOrderBy, -1, eDest, iParm, 
                             iCont, iBreak, 0);
        if( rc ){
          rc = 1;
          goto multi_select_end;
        }
        sqlite3VdbeResolveLabel(v, iCont);
        sqlite3VdbeAddOp(v, OP_Next, unionTab, iStart);
................................................................................

      /* INTERSECT is different from the others since it requires
      ** two temporary tables.  Hence it has its own case.  Begin
      ** by allocating the tables we will need.
      */
      tab1 = pParse->nTab++;
      tab2 = pParse->nTab++;
      if( p->pOrderBy && matchOrderbyToColumn(pParse,p,p->pOrderBy,tab1,1) ){
        rc = 1;
        goto multi_select_end;
      }


      addr = sqlite3VdbeAddOp(v, OP_OpenVirtual, tab1, 0);
      rc = multiSelectOpenVirtualAddr(p, addr);
      if( rc!=SQLITE_OK ){
        goto multi_select_end;
      }
      assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
      aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, tab1, 0);

      assert( p->pEList );

      /* Code the SELECTs to our left into temporary table "tab1".
      */
      rc = sqlite3Select(pParse, pPrior, SRT_Union, tab1, 0, 0, 0, aff);
      if( rc ){
        goto multi_select_end;
      }

      /* Code the current SELECT into temporary table "tab2"
      */
      addr = sqlite3VdbeAddOp(v, OP_OpenVirtual, tab2, 0);
      rc = multiSelectOpenVirtualAddr(p, addr);
      if( rc!=SQLITE_OK ){
        goto multi_select_end;
      }
      assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
      aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, tab2, 0);
      p->pPrior = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      rc = sqlite3Select(pParse, p, SRT_Union, tab2, 0, 0, 0, aff);
      p->pPrior = pPrior;
................................................................................
      iBreak = sqlite3VdbeMakeLabel(v);
      iCont = sqlite3VdbeMakeLabel(v);
      sqlite3VdbeAddOp(v, OP_Rewind, tab1, iBreak);
      computeLimitRegisters(pParse, p);
      iStart = sqlite3VdbeAddOp(v, OP_RowKey, tab1, 0);
      sqlite3VdbeAddOp(v, OP_NotFound, tab2, iCont);
      rc = selectInnerLoop(pParse, p, p->pEList, tab1, p->pEList->nExpr,
                             p->pOrderBy, -1, eDest, iParm, 
                             iCont, iBreak, 0);
      if( rc ){
        rc = 1;
        goto multi_select_end;
      }
      sqlite3VdbeResolveLabel(v, iCont);
      sqlite3VdbeAddOp(v, OP_Next, tab1, iStart);
................................................................................
    rc = 1;
    goto multi_select_end;
  }

  /* Set the number of columns in temporary tables
  */
  nCol = p->pEList->nExpr;
  while( nAddr>0 ){
    nAddr--;
    sqlite3VdbeChangeP2(v, aAddr[nAddr], nCol);
  }

  /* Compute collating sequences used by either the ORDER BY clause or
  ** by any temporary tables needed to implement the compound select.
  ** Attach the KeyInfo structure to all temporary tables.  Invoke the
  ** ORDER BY processing if there is an ORDER BY clause.
  **
  ** This section is run by the right-most SELECT statement only.
  ** SELECT statements to the left always skip this part.  The right-most
  ** SELECT might also skip this part if it has no ORDER BY clause and
  ** no temp tables are required.
  */
  if( p->pOrderBy || (pOpenVirtual && pOpenVirtual->nId>0) ){
    int i;                        /* Loop counter */
    KeyInfo *pKeyInfo;            /* Collating sequence for the result set */




    assert( p->ppOpenVirtual == &pOpenVirtual );

    pKeyInfo = sqliteMalloc(sizeof(*pKeyInfo)+nCol*sizeof(CollSeq*));
    if( !pKeyInfo ){
      rc = SQLITE_NOMEM;
      goto multi_select_end;
    }

    pKeyInfo->enc = pParse->db->enc;
    pKeyInfo->nField = nCol;

    for(i=0; i<nCol; i++){
      pKeyInfo->aColl[i] = multiSelectCollSeq(pParse, p, i);
      if( !pKeyInfo->aColl[i] ){
        pKeyInfo->aColl[i] = pParse->db->pDfltColl;
      }
    }

    for(i=0; pOpenVirtual && i<pOpenVirtual->nId; i++){
      int p3type = (i==0?P3_KEYINFO_HANDOFF:P3_KEYINFO);
      int addr = pOpenVirtual->a[i].idx;







      sqlite3VdbeChangeP3(v, addr, (char *)pKeyInfo, p3type);
    }


    if( p->pOrderBy ){
      struct ExprList_item *pOrderByTerm = p->pOrderBy->a;






      for(i=0; i<p->pOrderBy->nExpr; i++, pOrderByTerm++){
        Expr *pExpr = pOrderByTerm->pExpr;
        char *zName = pOrderByTerm->zName;
        assert( pExpr->op==TK_COLUMN && pExpr->iColumn<nCol );
        /* assert( !pExpr->pColl ); */
        if( zName ){
          pExpr->pColl = sqlite3LocateCollSeq(pParse, zName, -1);
        }else{
          pExpr->pColl = pKeyInfo->aColl[pExpr->iColumn];
        }
      }





      generateSortTail(pParse, p, v, p->pEList->nExpr, eDest, iParm);
    }

    if( !pOpenVirtual ){
      /* This happens for UNION ALL ... ORDER BY */
      sqliteFree(pKeyInfo);
    }
  }

multi_select_end:
  if( pOpenVirtual ){
    sqlite3IdListDelete(pOpenVirtual);
  }
  p->ppOpenVirtual = 0;
  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

#ifndef SQLITE_OMIT_VIEW
/*
** Scan through the expression pExpr.  Replace every reference to
................................................................................
  if( sqlite3_malloc_failed || pParse->nErr || p==0 ) return 1;
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
  */
  if( p->pPrior ){






    return multiSelect(pParse, p, eDest, iParm, aff);
  }
#endif

  saveAggregateInfo(pParse, &sAggInfo);
  pOrderBy = p->pOrderBy;
  if( eDest==SRT_Union || eDest==SRT_Except || eDest==SRT_Discard ){
................................................................................
#endif

  /* If there is an ORDER BY clause, resolve any collation sequences
  ** names that have been explicitly specified.
  */
  if( pOrderBy ){
    struct ExprList_item *pTerm;


    for(i=0, pTerm=pOrderBy->a; i<pOrderBy->nExpr; i++, pTerm++){
      if( pTerm->zName ){
        pTerm->pExpr->pColl = sqlite3LocateCollSeq(pParse, pTerm->zName, -1);
      }
    }
    if( pParse->nErr ){
      goto select_end;
    }





  }

  /* Set the limiter.
  */
  computeLimitRegisters(pParse, p);

  /* If the output is destined for a temporary table, open that table.
  */
  if( eDest==SRT_TempTable ){
    sqlite3VdbeAddOp(v, OP_OpenVirtual, iParm, 0);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, iParm, pEList->nExpr);
  }

  /* Do an analysis of aggregate expressions.
  */
  if( isAgg || pGroupBy ){
    NameContext sNC;
    memset(&sNC, 0, sizeof(sNC));
................................................................................
    sqlite3VdbeAddOp(v, eDest==SRT_Mem ? OP_Null : OP_Integer, 0, 0);
    sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
  }

  /* Open a virtual index to use for the distinct set.
  */
  if( isDistinct ){

    distinct = pParse->nTab++;
    openVirtualIndex(pParse, p, distinct);



  }else{
    distinct = -1;
  }

  /* Begin the database scan
  */
  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,







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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.258 2005/09/01 03:07:44 drh Exp $
*/
#include "sqliteInt.h"


/*
** Allocate a new Select structure and return a pointer to that
** structure.
................................................................................
    pNew->pOrderBy = pOrderBy;
    pNew->isDistinct = isDistinct;
    pNew->op = TK_SELECT;
    pNew->pLimit = pLimit;
    pNew->pOffset = pOffset;
    pNew->iLimit = -1;
    pNew->iOffset = -1;
    pNew->addrOpenVirt[0] = -1;
    pNew->addrOpenVirt[1] = -1;
    pNew->addrOpenVirt[2] = -1;
  }
  return pNew;
}

/*
** Given 1 to 3 identifiers preceeding the JOIN keyword, determine the
** type of join.  Return an integer constant that expresses that type
................................................................................

/*
** Insert code into "v" that will push the record on the top of the
** stack into the sorter.
*/
static void pushOntoSorter(Parse *pParse, Vdbe *v, ExprList *pOrderBy){
  sqlite3ExprCodeExprList(pParse, pOrderBy);
  sqlite3VdbeAddOp(v, OP_Pull, pOrderBy->nExpr, 0);
  sqlite3VdbeAddOp(v, OP_MakeRecord, pOrderBy->nExpr + 1, 0);
  sqlite3VdbeAddOp(v, OP_IdxInsert, pOrderBy->iTab, 0);
}

/*
** Add code to implement the OFFSET and LIMIT
*/
static void codeLimiter(
  Vdbe *v,          /* Generate code into this VM */
................................................................................
  }
  return 0;
}

/*
** Given an expression list, generate a KeyInfo structure that records
** the collating sequence for each expression in that expression list.
**
** If the ExprList is an ORDER BY or GROUP BY clause then the resulting
** KeyInfo structure is appropriate for initializing a virtual index to
** implement that clause.  If the ExprList is the result set of a SELECT
** then the KeyInfo structure is appropriate for initializing a virtual
** index to implement a DISTINCT test.
**
** Space to hold the KeyInfo structure is obtain from malloc.  The calling
** function is responsible for seeing that this structure is eventually
** freed.  Add the KeyInfo structure to the P3 field of an opcode using
** P3_KEYINFO_HANDOFF is the usual way of dealing with this.
*/
static KeyInfo *keyInfoFromExprList(Parse *pParse, ExprList *pList){
................................................................................
  Parse *pParse,   /* The parsing context */
  Select *p,       /* The SELECT statement */
  Vdbe *v,         /* Generate code into this VDBE */
  int nColumn,     /* Number of columns of data */
  int eDest,       /* Write the sorted results here */
  int iParm        /* Optional parameter associated with eDest */
){
  int brk = sqlite3VdbeMakeLabel(v);
  int cont = sqlite3VdbeMakeLabel(v);
  int addr;
  int iTab;
  ExprList *pOrderBy = p->pOrderBy;

  if( eDest==SRT_Sorter ) return;

  iTab = pOrderBy->iTab;

  addr = 1 + sqlite3VdbeAddOp(v, OP_Sort, iTab, brk);
  codeLimiter(v, p, cont, brk, 0);
  sqlite3VdbeAddOp(v, OP_Column, iTab, pOrderBy->nExpr);
  switch( eDest ){
    case SRT_Table:
    case SRT_TempTable: {
      sqlite3VdbeAddOp(v, OP_NewRowid, iParm, 0);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      sqlite3VdbeAddOp(v, OP_Insert, iParm, 0);
      break;
................................................................................
      sqlite3VdbeAddOp(v, OP_IdxInsert, (iParm&0x0000FFFF), 0);
      break;
    }
    case SRT_Exists:
    case SRT_Mem: {
      assert( nColumn==1 );
      sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
      sqlite3VdbeAddOp(v, OP_Goto, 0, brk);
      break;
    }
#endif
    case SRT_Callback:
    case SRT_Subroutine: {
      int i;
      sqlite3VdbeAddOp(v, OP_Integer, p->pEList->nExpr, 0);
................................................................................
      break;
    }
    default: {
      /* Do nothing */
      break;
    }
  }

  sqlite3VdbeResolveLabel(v, cont);
  sqlite3VdbeAddOp(v, OP_Next, iTab, addr);
  sqlite3VdbeResolveLabel(v, brk);

}

/*
** Return a pointer to a string containing the 'declaration type' of the
** expression pExpr. The string may be treated as static by the caller.
**
** If the declaration type is the exact datatype definition extracted from
................................................................................
    sqlite3VdbeAddOp(v, OP_MemStore, iMem, 1);
    VdbeComment((v, "# OFFSET counter"));
    p->iOffset = iMem;
  }
}

/*
** Allocate a virtual index to use for sorting.










*/
static createSortingIndex(Parse *pParse, Select *p, ExprList *pOrderBy){


  if( pOrderBy ){
    int addr;
    assert( pOrderBy->iTab==0 );
    pOrderBy->iTab = pParse->nTab++;
    addr = sqlite3VdbeAddOp(pParse->pVdbe, OP_OpenVirtual,
                            pOrderBy->iTab, pOrderBy->nExpr+1);
    assert( p->addrOpenVirt[2] == -1 );
    p->addrOpenVirt[2] = addr;
  }


}






















#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Return the appropriate collating sequence for the iCol-th column of
** the result set for the compound-select statement "p".  Return NULL if
** the column has no default collating sequence.
**
** The collating sequence for the compound select is taken from the
................................................................................
  int eDest,            /* \___  Store query results as specified */
  int iParm,            /* /     by these two parameters.         */
  char *aff             /* If eDest is SRT_Union, the affinity string */
){
  int rc = SQLITE_OK;   /* Success code from a subroutine */
  Select *pPrior;       /* Another SELECT immediately to our left */
  Vdbe *v;              /* Generate code to this VDBE */



  int nCol;             /* Number of columns in the result set */
  ExprList *pOrderBy;   /* The ORDER BY clause on p */
  int aSetP2[2];        /* Set P2 value of these op to number of columns */
  int nSetP2 = 0;       /* Number of slots in aSetP2[] used */

  /* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs.  Only
  ** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
  */
  if( p==0 || p->pPrior==0 ){
    rc = 1;
    goto multi_select_end;
  }
  pPrior = p->pPrior;
  assert( pPrior->pRightmost!=pPrior );
  assert( pPrior->pRightmost==p->pRightmost );
  if( pPrior->pOrderBy ){
    sqlite3ErrorMsg(pParse,"ORDER BY clause should come after %s not before",
      selectOpName(p->op));
    rc = 1;
    goto multi_select_end;
  }
  if( pPrior->pLimit ){
................................................................................
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    rc = 1;
    goto multi_select_end;
  }












  /* Create the destination temporary table if necessary
  */
  if( eDest==SRT_TempTable ){
    assert( p->pEList );
    assert( nSetP2<sizeof(aSetP2)/sizeof(aSetP2[0]) );
    aSetP2[nSetP2++] = sqlite3VdbeAddOp(v, OP_OpenVirtual, iParm, 0);

    eDest = SRT_Table;
  }

  /* Generate code for the left and right SELECT statements.
  */
  pOrderBy = p->pOrderBy;
  switch( p->op ){
    case TK_ALL: {
      if( pOrderBy==0 ){
        assert( !pPrior->pLimit );
        pPrior->pLimit = p->pLimit;
        pPrior->pOffset = p->pOffset;
        rc = sqlite3Select(pParse, pPrior, eDest, iParm, 0, 0, 0, aff);
        if( rc ){
          goto multi_select_end;
        }
................................................................................
    }
    case TK_EXCEPT:
    case TK_UNION: {
      int unionTab;    /* Cursor number of the temporary table holding result */
      int op = 0;      /* One of the SRT_ operations to apply to self */
      int priorOp;     /* The SRT_ operation to apply to prior selects */
      Expr *pLimit, *pOffset; /* Saved values of p->nLimit and p->nOffset */

      int addr;

      priorOp = p->op==TK_ALL ? SRT_Table : SRT_Union;
      if( eDest==priorOp && pOrderBy==0 && !p->pLimit && !p->pOffset ){
        /* We can reuse a temporary table generated by a SELECT to our
        ** right.
        */
        unionTab = iParm;
      }else{
        /* We will need to create our own temporary table to hold the
        ** intermediate results.
        */
        unionTab = pParse->nTab++;

        if( pOrderBy && matchOrderbyToColumn(pParse, p, pOrderBy, unionTab,1) ){
          rc = 1;
          goto multi_select_end;
        }
        addr = sqlite3VdbeAddOp(v, OP_OpenVirtual, unionTab, 0);
        if( priorOp==SRT_Table ){
          assert( nSetP2<sizeof(aSetP2)/sizeof(aSetP2[0]) );
          aSetP2[nSetP2++] = addr;
        }else{
          assert( p->addrOpenVirt[0] == -1 );
          p->addrOpenVirt[0] = addr;
          p->pRightmost->usesVirt = 1;
        }
        createSortingIndex(pParse, p, pOrderBy);
        assert( p->pEList );
      }

      /* Code the SELECT statements to our left
      */
      assert( !pPrior->pOrderBy );
      rc = sqlite3Select(pParse, pPrior, priorOp, unionTab, 0, 0, 0, aff);
................................................................................
      */
      switch( p->op ){
         case TK_EXCEPT:  op = SRT_Except;   break;
         case TK_UNION:   op = SRT_Union;    break;
         case TK_ALL:     op = SRT_Table;    break;
      }
      p->pPrior = 0;

      p->pOrderBy = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      rc = sqlite3Select(pParse, p, op, unionTab, 0, 0, 0, aff);
      p->pPrior = pPrior;
................................................................................
        }
        iBreak = sqlite3VdbeMakeLabel(v);
        iCont = sqlite3VdbeMakeLabel(v);
        sqlite3VdbeAddOp(v, OP_Rewind, unionTab, iBreak);
        computeLimitRegisters(pParse, p);
        iStart = sqlite3VdbeCurrentAddr(v);
        rc = selectInnerLoop(pParse, p, p->pEList, unionTab, p->pEList->nExpr,
                             pOrderBy, -1, eDest, iParm, 
                             iCont, iBreak, 0);
        if( rc ){
          rc = 1;
          goto multi_select_end;
        }
        sqlite3VdbeResolveLabel(v, iCont);
        sqlite3VdbeAddOp(v, OP_Next, unionTab, iStart);
................................................................................

      /* INTERSECT is different from the others since it requires
      ** two temporary tables.  Hence it has its own case.  Begin
      ** by allocating the tables we will need.
      */
      tab1 = pParse->nTab++;
      tab2 = pParse->nTab++;
      if( pOrderBy && matchOrderbyToColumn(pParse,p,pOrderBy,tab1,1) ){
        rc = 1;
        goto multi_select_end;
      }
      createSortingIndex(pParse, p, pOrderBy);

      addr = sqlite3VdbeAddOp(v, OP_OpenVirtual, tab1, 0);

      assert( p->addrOpenVirt[0] == -1 );
      p->addrOpenVirt[0] = addr;



      p->pRightmost->usesVirt = 1;
      assert( p->pEList );

      /* Code the SELECTs to our left into temporary table "tab1".
      */
      rc = sqlite3Select(pParse, pPrior, SRT_Union, tab1, 0, 0, 0, aff);
      if( rc ){
        goto multi_select_end;
      }

      /* Code the current SELECT into temporary table "tab2"
      */
      addr = sqlite3VdbeAddOp(v, OP_OpenVirtual, tab2, 0);
      assert( p->addrOpenVirt[1] == -1 );
      p->addrOpenVirt[1] = addr;




      p->pPrior = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      rc = sqlite3Select(pParse, p, SRT_Union, tab2, 0, 0, 0, aff);
      p->pPrior = pPrior;
................................................................................
      iBreak = sqlite3VdbeMakeLabel(v);
      iCont = sqlite3VdbeMakeLabel(v);
      sqlite3VdbeAddOp(v, OP_Rewind, tab1, iBreak);
      computeLimitRegisters(pParse, p);
      iStart = sqlite3VdbeAddOp(v, OP_RowKey, tab1, 0);
      sqlite3VdbeAddOp(v, OP_NotFound, tab2, iCont);
      rc = selectInnerLoop(pParse, p, p->pEList, tab1, p->pEList->nExpr,
                             pOrderBy, -1, eDest, iParm, 
                             iCont, iBreak, 0);
      if( rc ){
        rc = 1;
        goto multi_select_end;
      }
      sqlite3VdbeResolveLabel(v, iCont);
      sqlite3VdbeAddOp(v, OP_Next, tab1, iStart);
................................................................................
    rc = 1;
    goto multi_select_end;
  }

  /* Set the number of columns in temporary tables
  */
  nCol = p->pEList->nExpr;
  while( nSetP2 ){

    sqlite3VdbeChangeP2(v, aSetP2[--nSetP2], nCol);
  }

  /* Compute collating sequences used by either the ORDER BY clause or
  ** by any temporary tables needed to implement the compound select.
  ** Attach the KeyInfo structure to all temporary tables.  Invoke the
  ** ORDER BY processing if there is an ORDER BY clause.
  **
  ** This section is run by the right-most SELECT statement only.
  ** SELECT statements to the left always skip this part.  The right-most
  ** SELECT might also skip this part if it has no ORDER BY clause and
  ** no temp tables are required.
  */
  if( pOrderBy || p->usesVirt ){
    int i;                        /* Loop counter */
    KeyInfo *pKeyInfo;            /* Collating sequence for the result set */
    Select *pLoop;                /* For looping through SELECT statements */
    CollSeq **apColl;
    CollSeq **aCopy;


    assert( p->pRightmost==p );
    pKeyInfo = sqliteMalloc(sizeof(*pKeyInfo)+nCol*2*sizeof(CollSeq*));
    if( !pKeyInfo ){
      rc = SQLITE_NOMEM;
      goto multi_select_end;
    }

    pKeyInfo->enc = pParse->db->enc;
    pKeyInfo->nField = nCol;

    for(i=0, apColl=pKeyInfo->aColl; i<nCol; i++, apColl++){
      *apColl = multiSelectCollSeq(pParse, p, i);
      if( 0==*apColl ){
        *apColl = pParse->db->pDfltColl;
      }
    }

    for(pLoop=p; pLoop; pLoop=pLoop->pPrior){
      for(i=0; i<2; i++){
        int addr = pLoop->addrOpenVirt[i];
        if( addr<0 ){
          /* If [0] is unused then [1] is also unused.  So we can
          ** always safely abort as soon as the first unused slot is found */
          assert( pLoop->addrOpenVirt[1]<0 );
          break;
        }
        sqlite3VdbeChangeP2(v, addr, nCol);
        sqlite3VdbeChangeP3(v, addr, (char*)pKeyInfo, P3_KEYINFO);
      }
    }

    if( pOrderBy ){
      struct ExprList_item *pOTerm = pOrderBy->a;
      int nExpr = pOrderBy->nExpr;
      int addr;

      aCopy = (CollSeq**)&pKeyInfo[1];
      memcpy(aCopy, pKeyInfo->aColl, nCol*sizeof(CollSeq*));
      apColl = pKeyInfo->aColl;
      for(i=0; i<pOrderBy->nExpr; i++, pOTerm++, apColl++){
        Expr *pExpr = pOTerm->pExpr;
        char *zName = pOTerm->zName;
        assert( pExpr->op==TK_COLUMN && pExpr->iColumn<nCol );

        if( zName ){
          *apColl = sqlite3LocateCollSeq(pParse, zName, -1);
        }else{
          *apColl = aCopy[pExpr->iColumn];
        }
      }
      assert( p->pRightmost==p );
      assert( p->addrOpenVirt[2]>=0 );
      addr = p->addrOpenVirt[2];
      sqlite3VdbeChangeP2(v, addr, p->pEList->nExpr+1);
      sqlite3VdbeChangeP3(v, addr, (char*)pKeyInfo, P3_KEYINFO);
      generateSortTail(pParse, p, v, p->pEList->nExpr, eDest, iParm);
    }



    sqliteFree(pKeyInfo);
  }


multi_select_end:




  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

#ifndef SQLITE_OMIT_VIEW
/*
** Scan through the expression pExpr.  Replace every reference to
................................................................................
  if( sqlite3_malloc_failed || pParse->nErr || p==0 ) return 1;
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
  */
  if( p->pPrior ){
    if( p->pRightmost==0 ){
      Select *pLoop;
      for(pLoop=p; pLoop; pLoop=pLoop->pPrior){
        pLoop->pRightmost = p;
      }
    }
    return multiSelect(pParse, p, eDest, iParm, aff);
  }
#endif

  saveAggregateInfo(pParse, &sAggInfo);
  pOrderBy = p->pOrderBy;
  if( eDest==SRT_Union || eDest==SRT_Except || eDest==SRT_Discard ){
................................................................................
#endif

  /* If there is an ORDER BY clause, resolve any collation sequences
  ** names that have been explicitly specified.
  */
  if( pOrderBy ){
    struct ExprList_item *pTerm;
    KeyInfo *pKeyInfo;
    int addr;
    for(i=0, pTerm=pOrderBy->a; i<pOrderBy->nExpr; i++, pTerm++){
      if( pTerm->zName ){
        pTerm->pExpr->pColl = sqlite3LocateCollSeq(pParse, pTerm->zName, -1);
      }
    }
    if( pParse->nErr ){
      goto select_end;
    }
    pKeyInfo = keyInfoFromExprList(pParse, pOrderBy);
    pOrderBy->iTab = pParse->nTab++;
    addr = sqlite3VdbeOp3(v, OP_OpenVirtual, pOrderBy->iTab, pOrderBy->nExpr+1, 
                        (char*)pKeyInfo, P3_KEYINFO_HANDOFF);
    p->addrOpenVirt[2] = addr;
  }

  /* Set the limiter.
  */
  computeLimitRegisters(pParse, p);

  /* If the output is destined for a temporary table, open that table.
  */
  if( eDest==SRT_TempTable ){
    sqlite3VdbeAddOp(v, OP_OpenVirtual, iParm, pEList->nExpr);

  }

  /* Do an analysis of aggregate expressions.
  */
  if( isAgg || pGroupBy ){
    NameContext sNC;
    memset(&sNC, 0, sizeof(sNC));
................................................................................
    sqlite3VdbeAddOp(v, eDest==SRT_Mem ? OP_Null : OP_Integer, 0, 0);
    sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
  }

  /* Open a virtual index to use for the distinct set.
  */
  if( isDistinct ){
    KeyInfo *pKeyInfo;
    distinct = pParse->nTab++;

    pKeyInfo = keyInfoFromExprList(pParse, p->pEList);
    sqlite3VdbeOp3(v, OP_OpenVirtual, distinct, 0, 
                        (char*)pKeyInfo, P3_KEYINFO_HANDOFF);
  }else{
    distinct = -1;
  }

  /* Begin the database scan
  */
  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,

Changes to src/sqliteInt.h.

7
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1059
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**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.406 2005/08/30 00:54:03 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks
................................................................................
** list of "ID = expr" items in an UPDATE.  A list of expressions can
** also be used as the argument to a function, in which case the a.zName
** field is not used.
*/
struct ExprList {
  int nExpr;             /* Number of expressions on the list */
  int nAlloc;            /* Number of entries allocated below */

  struct ExprList_item {
    Expr *pExpr;           /* The list of expressions */
    char *zName;           /* Token associated with this expression */
    u8 sortOrder;          /* 1 for DESC or 0 for ASC */
    u8 isAgg;              /* True if this is an aggregate like count(*) */
    u8 done;               /* A flag to indicate when processing is finished */
    u8 orderByDup[2];      /* Corresponding term in OrderBy/GroupBy clause */
  } *a;                  /* One entry for each expression */
};

/*
** An instance of this structure can hold a simple list of identifiers,
** such as the list "a,b,c" in the following statements:
**
................................................................................
** needed to generate code for a single SELECT statement.
**
** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
** If there is a LIMIT clause, the parser sets nLimit to the value of the
** limit and nOffset to the value of the offset (or 0 if there is not
** offset).  But later on, nLimit and nOffset become the memory locations
** in the VDBE that record the limit and offset counters.










*/
struct Select {
  ExprList *pEList;      /* The fields of the result */
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  u8 isDistinct;         /* True if the DISTINCT keyword is present */



  SrcList *pSrc;         /* The FROM clause */
  Expr *pWhere;          /* The WHERE clause */
  ExprList *pGroupBy;    /* The GROUP BY clause */
  Expr *pHaving;         /* The HAVING clause */
  ExprList *pOrderBy;    /* The ORDER BY clause */
  Select *pPrior;        /* Prior select in a compound select statement */

  Expr *pLimit;          /* LIMIT expression. NULL means not used. */
  Expr *pOffset;         /* OFFSET expression. NULL means not used. */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
  IdList **ppOpenVirtual;/* OP_OpenVirtual addresses used by multi-selects */
  u8 isResolved;         /* True once sqlite3SelectResolve() has run. */
  u8 isAgg;              /* True if this is an aggregate query */
};

/*
** The results of a select can be distributed in several ways.
*/
#define SRT_Callback     1  /* Invoke a callback with each row of result */
#define SRT_Mem          2  /* Store result in a memory cell */







|







 







>






<







 







>
>
>
>
>
>
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>
>





>
>
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>



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<
<







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19
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883
884
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888
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891
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895

896
897
898
899
900
901
902
....
1041
1042
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1044
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1076


1077
1078
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1080
1081
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1083
**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.407 2005/09/01 03:07:44 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks
................................................................................
** list of "ID = expr" items in an UPDATE.  A list of expressions can
** also be used as the argument to a function, in which case the a.zName
** field is not used.
*/
struct ExprList {
  int nExpr;             /* Number of expressions on the list */
  int nAlloc;            /* Number of entries allocated below */
  int iTab;              /* VDBE Cursor associated with this ExprList */
  struct ExprList_item {
    Expr *pExpr;           /* The list of expressions */
    char *zName;           /* Token associated with this expression */
    u8 sortOrder;          /* 1 for DESC or 0 for ASC */
    u8 isAgg;              /* True if this is an aggregate like count(*) */
    u8 done;               /* A flag to indicate when processing is finished */

  } *a;                  /* One entry for each expression */
};

/*
** An instance of this structure can hold a simple list of identifiers,
** such as the list "a,b,c" in the following statements:
**
................................................................................
** needed to generate code for a single SELECT statement.
**
** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
** If there is a LIMIT clause, the parser sets nLimit to the value of the
** limit and nOffset to the value of the offset (or 0 if there is not
** offset).  But later on, nLimit and nOffset become the memory locations
** in the VDBE that record the limit and offset counters.
**
** addrOpenVirt[] entries contain the address of OP_OpenVirtual opcodes.
** These addresses must be stored so that we can go back and fill in
** the P3_KEYINFO and P2 parameters later.  Neither the KeyInfo nor
** the number of columns in P2 can be computed at the same time
** as the OP_OpenVirtual instruction is coded because not
** enough information about the compound query is known at that point.
** The KeyInfo for addrOpenVirt[0] and [1] contains collating sequences
** for the result set.  The KeyInfo for addrOpenVirt[2] contains collating
** sequences for the ORDER BY clause.
*/
struct Select {
  ExprList *pEList;      /* The fields of the result */
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  u8 isDistinct;         /* True if the DISTINCT keyword is present */
  u8 isResolved;         /* True once sqlite3SelectResolve() has run. */
  u8 isAgg;              /* True if this is an aggregate query */
  u8 usesVirt;           /* True if uses an OpenVirtual opcode */
  SrcList *pSrc;         /* The FROM clause */
  Expr *pWhere;          /* The WHERE clause */
  ExprList *pGroupBy;    /* The GROUP BY clause */
  Expr *pHaving;         /* The HAVING clause */
  ExprList *pOrderBy;    /* The ORDER BY clause */
  Select *pPrior;        /* Prior select in a compound select statement */
  Select *pRightmost;    /* Right-most select in a compound select statement */
  Expr *pLimit;          /* LIMIT expression. NULL means not used. */
  Expr *pOffset;         /* OFFSET expression. NULL means not used. */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
  int addrOpenVirt[3];   /* OP_OpenVirtual opcodes related to this select */


};

/*
** The results of a select can be distributed in several ways.
*/
#define SRT_Callback     1  /* Invoke a callback with each row of result */
#define SRT_Mem          2  /* Store result in a memory cell */

Changes to src/vdbe.c.

39
40
41
42
43
44
45
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47
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49
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53
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...
631
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....
2599
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2602
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2612

2613
2614
2615
2616
2617
2618
2619
....
2646
2647
2648
2649
2650
2651
2652

2653
2654
2655
2656
2657
2658
2659
....
3460
3461
3462
3463
3464
3465
3466

















3467
3468
3469
3470
3471
3472
3473
....
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
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4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
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4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
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4131
4132
4133
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4135
4136
4137
4138
4139
4140
4141
4142
4143
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4145
4146
4147
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4149
4150
4151
4152
4153
4154
4155
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4157
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4159
4160
4161
4162
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4164
4165
4166
4167
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4195
4196
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4198
4199
4200
4201
4202
**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.478 2005/07/28 20:51:19 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
................................................................................
    N--;
    Release(pTos);
    pTos--;
  }
  *ppTos = pTos;
}

/*
** The parameters are pointers to the head of two sorted lists
** of Sorter structures.  Merge these two lists together and return
** a single sorted list.  This routine forms the core of the merge-sort
** algorithm.
**
** In the case of a tie, left sorts in front of right.
*/
static Sorter *Merge(Sorter *pLeft, Sorter *pRight, KeyInfo *pKeyInfo){
  Sorter sHead;
  Sorter *pTail;
  pTail = &sHead;
  pTail->pNext = 0;
  while( pLeft && pRight ){
    int c = sqlite3VdbeRecordCompare(pKeyInfo, pLeft->nKey, pLeft->zKey,
                                     pRight->nKey, pRight->zKey);
    if( c<=0 ){
      pTail->pNext = pLeft;
      pLeft = pLeft->pNext;
    }else{
      pTail->pNext = pRight;
      pRight = pRight->pNext;
    }
    pTail = pTail->pNext;
  }
  if( pLeft ){
    pTail->pNext = pLeft;
  }else if( pRight ){
    pTail->pNext = pRight;
  }
  return sHead.pNext;
}

/*
** Allocate cursor number iCur.  Return a pointer to it.  Return NULL
** if we run out of memory.
*/
static Cursor *allocateCursor(Vdbe *p, int iCur){
  Cursor *pCx;
  assert( iCur<p->nCursor );
................................................................................
  p->returnDepth--;
  pc = p->returnStack[p->returnDepth] - 1;
  break;
}

/* Opcode:  Halt P1 P2 P3
**
** Exit immediately.  All open cursors, Lists, Sorts, etc are closed
** automatically.
**
** P1 is the result code returned by sqlite3_exec(), sqlite3_reset(),
** or sqlite3_finalize().  For a normal halt, this should be SQLITE_OK (0).
** For errors, it can be some other value.  If P1!=0 then P2 will determine
** whether or not to rollback the current transaction.  Do not rollback
** if P2==OE_Fail. Do the rollback if P2==OE_Rollback.  If P2==OE_Abort,
................................................................................
    default: {
      goto abort_due_to_error;
    }
  }
  break;
}

/* Opcode: OpenVirtual P1 * P3
**
** Open a new cursor to a transient or virtual table.
** The cursor is always opened read/write even if 
** the main database is read-only.  The transient or virtual
** table is deleted automatically when the cursor is closed.
**

** The cursor points to a BTree table if P3==0 and to a BTree index
** if P3 is not 0.  If P3 is not NULL, it points to a KeyInfo structure
** that defines the format of keys in the index.
*/
case OP_OpenVirtual: {       /* no-push */
  int i = pOp->p1;
  Cursor *pCx;
................................................................................
      pCx->isTable = 0;
    }else{
      rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, 1, 0, 0, &pCx->pCursor);
      pCx->isTable = 1;
      pCx->pIncrKey = &pCx->bogusIncrKey;
    }
  }

  pCx->isIndex = !pCx->isTable;
  break;
}

#ifndef SQLITE_OMIT_TRIGGER
/* Opcode: OpenPseudo P1 * *
**
................................................................................
    }
  }else{
    pC->nullRow = 0;
  }
  break;
}


















/* Opcode: Rewind P1 P2 *
**
** The next use of the Rowid or Column or Next instruction for P1 
** will refer to the first entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
................................................................................
  p->nChange = pContext->nChange;
  sqlite3VdbeFifoClear(&p->sFifo);
  p->sFifo = pContext->sFifo;
  break;
}
#endif /* #ifndef SQLITE_OMIT_TRIGGER */

/* Opcode: SortInsert * * *
**
** The TOS is the key and the NOS is the data.  Pop both from the stack
** and put them on the sorter.  The key and data should have been
** made using the MakeRecord opcode.
*/
case OP_SortInsert: {        /* no-push */
  Mem *pNos = &pTos[-1];
  Sorter *pSorter;
  assert( pNos>=p->aStack );
  if( Dynamicify(pTos, db->enc) ) goto no_mem;
  pSorter = sqliteMallocRaw( sizeof(Sorter) );
  if( pSorter==0 ) goto no_mem;
  pSorter->pNext = 0;
  if( p->pSortTail ){
    p->pSortTail->pNext = pSorter;
  }else{
    p->pSort = pSorter;
  }
  p->pSortTail = pSorter;
  assert( pTos->flags & MEM_Dyn );
  pSorter->nKey = pTos->n;
  pSorter->zKey = pTos->z;
  pSorter->data.flags = MEM_Null;
  rc = sqlite3VdbeMemMove(&pSorter->data, pNos);
  pTos -= 2;
  break;
}

/* Opcode: Sort * * P3
**
** Sort all elements on the sorter.  The algorithm is a
** mergesort.  The P3 argument is a pointer to a KeyInfo structure
** that describes the keys to be sorted.
*/
case OP_Sort: {        /* no-push */
  int i;
  KeyInfo *pKeyInfo = (KeyInfo*)pOp->p3;
  Sorter *pElem;
  Sorter *apSorter[NSORT];
  sqlite3_sort_count++;
  pKeyInfo->enc = p->db->enc;
  for(i=0; i<NSORT; i++){
    apSorter[i] = 0;
  }
  while( p->pSort ){
    pElem = p->pSort;
    p->pSort = pElem->pNext;
    pElem->pNext = 0;
    for(i=0; i<NSORT-1; i++){
      if( apSorter[i]==0 ){
        apSorter[i] = pElem;
        break;
      }else{
        pElem = Merge(apSorter[i], pElem, pKeyInfo);
        apSorter[i] = 0;
      }
    }
    if( i>=NSORT-1 ){
      apSorter[NSORT-1] = Merge(apSorter[NSORT-1],pElem, pKeyInfo);
    }
  }
  pElem = 0;
  for(i=0; i<NSORT; i++){
    pElem = Merge(apSorter[i], pElem, pKeyInfo);
  }
  p->pSort = pElem;
  break;
}

/* Opcode: SortNext * P2 *
**
** Push the data for the topmost element in the sorter onto the
** stack, then remove the element from the sorter.  If the sorter
** is empty, push nothing on the stack and instead jump immediately 
** to instruction P2.
*/
case OP_SortNext: {
  Sorter *pSorter = p->pSort;
  CHECK_FOR_INTERRUPT;
  if( pSorter!=0 ){
    p->pSort = pSorter->pNext;
    pTos++;
    pTos->flags = MEM_Null;
    rc = sqlite3VdbeMemMove(pTos, &pSorter->data);
    sqliteFree(pSorter->zKey);
    sqliteFree(pSorter);
  }else{
    pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: SortReset * * *
**
** Remove any elements that remain on the sorter.
*/
case OP_SortReset: {        /* no-push */
  sqlite3VdbeSorterReset(p);
  break;
}

/* Opcode: MemStore P1 P2 *
**
** Write the top of the stack into memory location P1.
** P1 should be a small integer since space is allocated
** for all memory locations between 0 and P1 inclusive.
**
** After the data is stored in the memory location, the







|







 







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**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.479 2005/09/01 03:07:44 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
................................................................................
    N--;
    Release(pTos);
    pTos--;
  }
  *ppTos = pTos;
}


































/*
** Allocate cursor number iCur.  Return a pointer to it.  Return NULL
** if we run out of memory.
*/
static Cursor *allocateCursor(Vdbe *p, int iCur){
  Cursor *pCx;
  assert( iCur<p->nCursor );
................................................................................
  p->returnDepth--;
  pc = p->returnStack[p->returnDepth] - 1;
  break;
}

/* Opcode:  Halt P1 P2 P3
**
** Exit immediately.  All open cursors, Fifos, etc are closed
** automatically.
**
** P1 is the result code returned by sqlite3_exec(), sqlite3_reset(),
** or sqlite3_finalize().  For a normal halt, this should be SQLITE_OK (0).
** For errors, it can be some other value.  If P1!=0 then P2 will determine
** whether or not to rollback the current transaction.  Do not rollback
** if P2==OE_Fail. Do the rollback if P2==OE_Rollback.  If P2==OE_Abort,
................................................................................
    default: {
      goto abort_due_to_error;
    }
  }
  break;
}

/* Opcode: OpenVirtual P1 P2 P3
**
** Open a new cursor P1 to a transient or virtual table.
** The cursor is always opened read/write even if 
** the main database is read-only.  The transient or virtual
** table is deleted automatically when the cursor is closed.
**
** P2 is the number of columns in the virtual table.
** The cursor points to a BTree table if P3==0 and to a BTree index
** if P3 is not 0.  If P3 is not NULL, it points to a KeyInfo structure
** that defines the format of keys in the index.
*/
case OP_OpenVirtual: {       /* no-push */
  int i = pOp->p1;
  Cursor *pCx;
................................................................................
      pCx->isTable = 0;
    }else{
      rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, 1, 0, 0, &pCx->pCursor);
      pCx->isTable = 1;
      pCx->pIncrKey = &pCx->bogusIncrKey;
    }
  }
  pCx->nField = pOp->p2;
  pCx->isIndex = !pCx->isTable;
  break;
}

#ifndef SQLITE_OMIT_TRIGGER
/* Opcode: OpenPseudo P1 * *
**
................................................................................
    }
  }else{
    pC->nullRow = 0;
  }
  break;
}


/* Opcode: Sort P1 P2 *
**
** This opcode does exactly the same thing as OP_Rewind except that
** it increments an undocumented global variable used for testing.
**
** Sorting is accomplished by writing records into a sorting index,
** then rewinding that index and playing it back from beginning to
** end.  We use the OP_Sort opcode instead of OP_Rewind to do the
** rewinding so that the global variable will be incremented and
** regression tests can determine whether or not the optimizer is
** correctly optimizing out sorts.
*/
case OP_Sort: {        /* no-push */
  sqlite3_sort_count++;
  /* Fall through into OP_Rewind */
}
/* Opcode: Rewind P1 P2 *
**
** The next use of the Rowid or Column or Next instruction for P1 
** will refer to the first entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
................................................................................
  p->nChange = pContext->nChange;
  sqlite3VdbeFifoClear(&p->sFifo);
  p->sFifo = pContext->sFifo;
  break;
}
#endif /* #ifndef SQLITE_OMIT_TRIGGER */







































































































/* Opcode: MemStore P1 P2 *
**
** Write the top of the stack into memory location P1.
** P1 should be a small integer since space is allocated
** for all memory locations between 0 and P1 inclusive.
**
** After the data is stored in the memory location, the

Changes to src/vdbeInt.h.

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  double r;           /* Real value */
  char *z;            /* String or BLOB value */
  void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
  char zShort[NBFS];  /* Space for short strings */
};
typedef struct Mem Mem;

/*
** A sorter builds a list of elements to be sorted.  Each element of
** the list is an instance of the following structure.
*/
typedef struct Sorter Sorter;
struct Sorter {
  int nKey;           /* Number of bytes in the key */
  char *zKey;         /* The key by which we will sort */
  Mem data;
  Sorter *pNext;      /* Next in the list */
};

/* 
** Number of buckets used for merge-sort.  
*/
#define NSORT 30

/* One or more of the following flags are set to indicate the validOK
** representations of the value stored in the Mem struct.
**
** If the MEM_Null flag is set, then the value is an SQL NULL value.
** No other flags may be set in this case.
**
** If the MEM_Str flag is set then Mem.z points at a string representation.
................................................................................
  int *aLabel;        /* Space to hold the labels */
  Mem *aStack;        /* The operand stack, except string values */
  Mem *pTos;          /* Top entry in the operand stack */
  Mem **apArg;        /* Arguments to currently executing user function */
  Mem *aColName;      /* Column names to return */
  int nCursor;        /* Number of slots in apCsr[] */
  Cursor **apCsr;     /* One element of this array for each open cursor */
  Sorter *pSort;      /* A linked list of objects to be sorted */
  Sorter *pSortTail;  /* Last element on the pSort list */
  int nVar;           /* Number of entries in aVar[] */
  Mem *aVar;          /* Values for the OP_Variable opcode. */
  char **azVar;       /* Name of variables */
  int okVar;          /* True if azVar[] has been initialized */
  int magic;              /* Magic number for sanity checking */
  int nMem;               /* Number of memory locations currently allocated */
  Mem *aMem;              /* The memory locations */
................................................................................
#define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
#define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */

/*
** Function prototypes
*/
void sqlite3VdbeFreeCursor(Cursor*);
void sqlite3VdbeSorterReset(Vdbe*);
int sqlite3VdbeAggReset(sqlite3*, Agg *, KeyInfo *);
void sqliteVdbePopStack(Vdbe*,int);
int sqlite3VdbeCursorMoveto(Cursor*);
#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
void sqlite3VdbePrintOp(FILE*, int, Op*);
#endif
#ifdef SQLITE_DEBUG







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  double r;           /* Real value */
  char *z;            /* String or BLOB value */
  void (*xDel)(void *);  /* If not null, call this function to delete Mem.z */
  char zShort[NBFS];  /* Space for short strings */
};
typedef struct Mem Mem;


















/* One or more of the following flags are set to indicate the validOK
** representations of the value stored in the Mem struct.
**
** If the MEM_Null flag is set, then the value is an SQL NULL value.
** No other flags may be set in this case.
**
** If the MEM_Str flag is set then Mem.z points at a string representation.
................................................................................
  int *aLabel;        /* Space to hold the labels */
  Mem *aStack;        /* The operand stack, except string values */
  Mem *pTos;          /* Top entry in the operand stack */
  Mem **apArg;        /* Arguments to currently executing user function */
  Mem *aColName;      /* Column names to return */
  int nCursor;        /* Number of slots in apCsr[] */
  Cursor **apCsr;     /* One element of this array for each open cursor */


  int nVar;           /* Number of entries in aVar[] */
  Mem *aVar;          /* Values for the OP_Variable opcode. */
  char **azVar;       /* Name of variables */
  int okVar;          /* True if azVar[] has been initialized */
  int magic;              /* Magic number for sanity checking */
  int nMem;               /* Number of memory locations currently allocated */
  Mem *aMem;              /* The memory locations */
................................................................................
#define VDBE_MAGIC_HALT     0x519c2973    /* VDBE has completed execution */
#define VDBE_MAGIC_DEAD     0xb606c3c8    /* The VDBE has been deallocated */

/*
** Function prototypes
*/
void sqlite3VdbeFreeCursor(Cursor*);

int sqlite3VdbeAggReset(sqlite3*, Agg *, KeyInfo *);
void sqliteVdbePopStack(Vdbe*,int);
int sqlite3VdbeCursorMoveto(Cursor*);
#if defined(SQLITE_DEBUG) || defined(VDBE_PROFILE)
void sqlite3VdbePrintOp(FILE*, int, Op*);
#endif
#ifdef SQLITE_DEBUG

Changes to src/vdbeaux.c.

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      p->aOp[i].cnt = 0;
      p->aOp[i].cycles = 0;
    }
  }
#endif
}


/*
** Remove any elements that remain on the sorter for the VDBE given.
*/
void sqlite3VdbeSorterReset(Vdbe *p){
  while( p->pSort ){
    Sorter *pSorter = p->pSort;
    p->pSort = pSorter->pNext;
    sqliteFree(pSorter->zKey);
    sqlite3VdbeMemRelease(&pSorter->data);
    sqliteFree(pSorter);
  }
  p->pSortTail = 0;
}

/*
** Free all resources allociated with AggElem pElem, an element of
** aggregate pAgg.
*/
static void freeAggElem(AggElem *pElem, Agg *pAgg){
  int i;
  for(i=0; i<pAgg->nMem; i++){
................................................................................
  sqlite3VdbeFifoClear(&p->sFifo);
  if( p->contextStack ){
    for(i=0; i<p->contextStackTop; i++){
      sqlite3VdbeFifoClear(&p->contextStack[i].sFifo);
    }
    sqliteFree(p->contextStack);
  }
  sqlite3VdbeSorterReset(p);
  for(i=0; i<p->nAgg; i++){
    sqlite3VdbeAggReset(0, &p->apAgg[i], 0);
  }
  p->contextStack = 0;
  p->contextStackDepth = 0;
  p->contextStackTop = 0;
  sqliteFree(p->zErrMsg);







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      p->aOp[i].cnt = 0;
      p->aOp[i].cycles = 0;
    }
  }
#endif
}
















/*
** Free all resources allociated with AggElem pElem, an element of
** aggregate pAgg.
*/
static void freeAggElem(AggElem *pElem, Agg *pAgg){
  int i;
  for(i=0; i<pAgg->nMem; i++){
................................................................................
  sqlite3VdbeFifoClear(&p->sFifo);
  if( p->contextStack ){
    for(i=0; i<p->contextStackTop; i++){
      sqlite3VdbeFifoClear(&p->contextStack[i].sFifo);
    }
    sqliteFree(p->contextStack);
  }

  for(i=0; i<p->nAgg; i++){
    sqlite3VdbeAggReset(0, &p->apAgg[i], 0);
  }
  p->contextStack = 0;
  p->contextStackDepth = 0;
  p->contextStackTop = 0;
  sqliteFree(p->zErrMsg);

Changes to test/conflict.test.

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#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for the conflict resolution extension
# to SQLite.
#
# $Id: conflict.test,v 1.24 2005/06/07 02:12:30 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Create tables for the first group of tests.
#
do_test conflict-1.0 {
................................................................................
#   t0     True if there is an error from $cmd
#   t1     Content of "b" column of t1 assuming no error in $cmd
#   t2     Content of "x" column of t3
#   t3     Number of temporary files created
#
foreach {i conf1 cmd t0 t1 t2 t3} {
  1 {}       UPDATE                  1 {6 7 8 9}  1 1
  2 REPLACE  UPDATE                  0 {7 6 9}    1 0
  3 IGNORE   UPDATE                  0 {6 7 3 9}  1 0
  4 FAIL     UPDATE                  1 {6 7 3 4}  1 0
  5 ABORT    UPDATE                  1 {1 2 3 4}  1 1
  6 ROLLBACK UPDATE                  1 {1 2 3 4}  0 0
  7 REPLACE  {UPDATE OR IGNORE}      0 {6 7 3 9}  1 0
  8 IGNORE   {UPDATE OR REPLACE}     0 {7 6 9}    1 0
  9 FAIL     {UPDATE OR IGNORE}      0 {6 7 3 9}  1 0
 10 ABORT    {UPDATE OR REPLACE}     0 {7 6 9}    1 0
 11 ROLLBACK {UPDATE OR IGNORE}      0 {6 7 3 9}  1 0
 12 {}       {UPDATE OR IGNORE}      0 {6 7 3 9}  1 0
 13 {}       {UPDATE OR REPLACE}     0 {7 6 9}    1 0
 14 {}       {UPDATE OR FAIL}        1 {6 7 3 4}  1 0
 15 {}       {UPDATE OR ABORT}       1 {1 2 3 4}  1 1
 16 {}       {UPDATE OR ROLLBACK}    1 {1 2 3 4}  0 0
} {
  if {$t0} {set t1 {column a is not unique}}
  do_test conflict-6.$i {
    db close







|







 







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#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for the conflict resolution extension
# to SQLite.
#
# $Id: conflict.test,v 1.25 2005/09/01 03:07:45 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Create tables for the first group of tests.
#
do_test conflict-1.0 {
................................................................................
#   t0     True if there is an error from $cmd
#   t1     Content of "b" column of t1 assuming no error in $cmd
#   t2     Content of "x" column of t3
#   t3     Number of temporary files created
#
foreach {i conf1 cmd t0 t1 t2 t3} {
  1 {}       UPDATE                  1 {6 7 8 9}  1 1
  2 REPLACE  UPDATE                  0 {7 6 9}    1 1
  3 IGNORE   UPDATE                  0 {6 7 3 9}  1 1
  4 FAIL     UPDATE                  1 {6 7 3 4}  1 0
  5 ABORT    UPDATE                  1 {1 2 3 4}  1 1
  6 ROLLBACK UPDATE                  1 {1 2 3 4}  0 0
  7 REPLACE  {UPDATE OR IGNORE}      0 {6 7 3 9}  1 1
  8 IGNORE   {UPDATE OR REPLACE}     0 {7 6 9}    1 1
  9 FAIL     {UPDATE OR IGNORE}      0 {6 7 3 9}  1 1
 10 ABORT    {UPDATE OR REPLACE}     0 {7 6 9}    1 1
 11 ROLLBACK {UPDATE OR IGNORE}      0 {6 7 3 9}  1 1
 12 {}       {UPDATE OR IGNORE}      0 {6 7 3 9}  1 1
 13 {}       {UPDATE OR REPLACE}     0 {7 6 9}    1 1
 14 {}       {UPDATE OR FAIL}        1 {6 7 3 4}  1 0
 15 {}       {UPDATE OR ABORT}       1 {1 2 3 4}  1 1
 16 {}       {UPDATE OR ROLLBACK}    1 {1 2 3 4}  0 0
} {
  if {$t0} {set t1 {column a is not unique}}
  do_test conflict-6.$i {
    db close