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Progress toward fixing iproblems with compound selects. (CVS 1911)

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FossilOrigin-Name: 307478593d5d96b79386da222c7742ea2eaa5467
This commit is contained in:
drh
2004-08-29 01:31:05 +00:00
parent 6f3a3efe03
commit fbc4ee7b70
3 changed files with 82 additions and 33 deletions
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101
src/select.c
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@@ -12,7 +12,7 @@
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.203 2004/08/21 17:54:45 drh Exp $
** $Id: select.c,v 1.204 2004/08/29 01:31:05 drh Exp $
*/
#include "sqliteInt.h"
@@ -1279,26 +1279,54 @@ static int openTempIndex(Parse *pParse, Select *p, int iTab, int keyAsData){
return addr;
}
/*
** FIX ME:
** + Omit the ppOpenTemp parameter from multiSelectOpenTempAddr().
** + Attach pOpenList to the right-most term always.
** + Make sure Select.ppOpenTemp is initialized to NULL
*/
/*
** Add the address "addr" to the set of all opcode addresses contained
** in the pOpenTemp list for the whole compound select. If no pOpenTemp
** list has been created yet, then create a new one and make *ppOpenTemp
** point to it. If the pOpenTemp list already exists, leave *ppOpenTemp
** unchanged and just add the new address to the existing list.
*/
static int multiSelectOpenTempAddr(Select *p, int addr, IdList **ppOpenTemp){
IdList *pList;
if( !p->ppOpenTemp ){
/* Create a new list */
*ppOpenTemp = sqlite3IdListAppend(0, 0);
p->ppOpenTemp = ppOpenTemp;
}else{
/* Add a new element onto the end of the existing list */
*p->ppOpenTemp = sqlite3IdListAppend(*p->ppOpenTemp, 0);
}
if( !(*p->ppOpenTemp) ){
pList = *p->ppOpenTemp;
if( pList==0 ){
return SQLITE_NOMEM;
}
(*p->ppOpenTemp)->a[(*p->ppOpenTemp)->nId-1].idx = addr;
pList->a[pList->nId-1].idx = addr;
return SQLITE_OK;
}
/*
** 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
** left-most term of the select that has a collating sequence.
*/
static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){
CollSeq *pRet = 0;
CollSeq *pRet;
if( p->pPrior ){
pRet = multiSelectCollSeq(pParse, p->pPrior, iCol);
}else{
pRet = 0;
}
if( !pRet ){
if( pRet==0 ){
pRet = sqlite3ExprCollSeq(pParse, p->pEList->a[iCol].pExpr);
}
return pRet;
@@ -1335,19 +1363,19 @@ static CollSeq *multiSelectCollSeq(Parse *pParse, Select *p, int iCol){
** individual selects always group from left to right.
*/
static int multiSelect(
Parse *pParse,
Select *p,
int eDest,
int iParm,
char *aff /* If eDest is SRT_Union, the affinity string */
Parse *pParse, /* Parsing context */
Select *p, /* The right-most of SELECTs to be coded */
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 *pOpenTemp = 0;
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 *pOpenTemp = 0;/* OP_OpenTemp opcodes that need a KeyInfo */
/* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs. Only
** the last SELECT in the series may have an ORDER BY or LIMIT.
** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
*/
if( p==0 || p->pPrior==0 ){
rc = 1;
@@ -1375,11 +1403,26 @@ static int multiSelect(
goto multi_select_end;
}
/* PART OF FIX:
*/
if( p->ppOpenTemp==0 ){
p->ppOpenTemp = &pOpenTemp;
}
pPrior->ppOpenTemp = p->ppOpenTemp;
/* Create the destination temporary table if necessary
*/
if( eDest==SRT_TempTable ){
assert( p->pEList );
sqlite3VdbeAddOp(v, OP_OpenTemp, iParm, 0);
/* FIX ME:
** p->pEList->nExpr might contain a "*" and so might not be the
** correct number. Go ahead and code the SetNumColumns instruction
** here, but also record its address. Change the P2 value of the
** instruction to the number of columns after sqlite3Select() has
** been called to code the subquery and has modified pEList->nExpr
** to be the correct value. */
sqlite3VdbeAddOp(v, OP_SetNumColumns, iParm, p->pEList->nExpr);
eDest = SRT_Table;
}
@@ -1391,7 +1434,7 @@ static int multiSelect(
if( p->pOrderBy==0 ){
pPrior->nLimit = p->nLimit;
pPrior->nOffset = p->nOffset;
pPrior->ppOpenTemp = p->ppOpenTemp;
/* pPrior->ppOpenTemp = p->ppOpenTemp; // FIX */
rc = sqlite3Select(pParse, pPrior, eDest, iParm, 0, 0, 0, aff);
if( rc ){
goto multi_select_end;
@@ -1448,7 +1491,7 @@ static int multiSelect(
/* Code the SELECT statements to our left
*/
pPrior->ppOpenTemp = p->ppOpenTemp;
/* pPrior->ppOpenTemp = p->ppOpenTemp; // FIX */
rc = sqlite3Select(pParse, pPrior, priorOp, unionTab, 0, 0, 0, aff);
if( rc ){
goto multi_select_end;
@@ -1536,7 +1579,7 @@ static int multiSelect(
/* Code the SELECTs to our left into temporary table "tab1".
*/
pPrior->ppOpenTemp = p->ppOpenTemp;
/* pPrior->ppOpenTemp = p->ppOpenTemp; // FIX */
rc = sqlite3Select(pParse, pPrior, SRT_Union, tab1, 0, 0, 0, aff);
if( rc ){
goto multi_select_end;
@@ -1599,10 +1642,17 @@ static int multiSelect(
goto multi_select_end;
}
/* 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.
*/
if( p->pOrderBy || (pOpenTemp && pOpenTemp->nId>0) ){
int nCol = p->pEList->nExpr;
int i;
KeyInfo *pKeyInfo = sqliteMalloc(sizeof(*pKeyInfo)+nCol*sizeof(CollSeq*));
int nCol = p->pEList->nExpr; /* Number of columns in the result set */
int i; /* Loop counter */
KeyInfo *pKeyInfo; /* Collating sequence for the result set */
pKeyInfo = sqliteMalloc(sizeof(*pKeyInfo)+nCol*sizeof(CollSeq*));
if( !pKeyInfo ){
rc = SQLITE_NOMEM;
goto multi_select_end;
@@ -1625,9 +1675,10 @@ static int multiSelect(
}
if( p->pOrderBy ){
for(i=0; i<p->pOrderBy->nExpr; i++){
Expr *pExpr = p->pOrderBy->a[i].pExpr;
char *zName = p->pOrderBy->a[i].zName;
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 ){
@@ -2318,7 +2369,6 @@ int sqlite3Select(
generateColumnNames(pParse, pTabList, pEList);
}
#if 1 /* I do not think we need the following code any more.... */
/* If the destination is SRT_Union, then set the number of columns in
** the records that will be inserted into the temporary table. The caller
** couldn't do this, in case the select statement is of the form
@@ -2333,7 +2383,6 @@ int sqlite3Select(
if( eDest==SRT_Union ){
sqlite3VdbeAddOp(v, OP_SetNumColumns, iParm, pEList->nExpr);
}
#endif
/* Generate code for all sub-queries in the FROM clause
*/