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Modify sub-query handling. Tickets #1083 and #1084. (CVS 2286)

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FossilOrigin-Name: b1b50f315873a8614920d1e3af4a07fb29a7ff6a
This commit is contained in:
danielk1977
2005-01-29 08:32:43 +00:00
parent c9ec413a08
commit b3bce66232
27 changed files with 833 additions and 449 deletions
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217
src/expr.c
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@@ -12,7 +12,7 @@
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.188 2005/01/23 22:41:37 danielk1977 Exp $
** $Id: expr.c,v 1.189 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
@@ -516,6 +516,8 @@ Select *sqlite3SelectDup(Select *p){
pNew->iOffset = -1;
pNew->ppOpenTemp = 0;
pNew->pFetch = 0;
pNew->isResolved = 0;
pNew->isAgg = 0;
return pNew;
}
#else
@@ -750,40 +752,42 @@ static int lookupName(
pNC->nRef++;
/* assert( zTab==0 || pEList==0 ); */
for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
Table *pTab = pItem->pTab;
Column *pCol;
if( pTab==0 ) continue;
assert( pTab->nCol>0 );
if( zTab ){
if( pItem->zAlias ){
char *zTabName = pItem->zAlias;
if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
}else{
char *zTabName = pTab->zName;
if( zTabName==0 || sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
if( zDb!=0 && sqlite3StrICmp(db->aDb[pTab->iDb].zName, zDb)!=0 ){
continue;
if( pSrcList ){
for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
Table *pTab = pItem->pTab;
Column *pCol;
if( pTab==0 ) continue;
assert( pTab->nCol>0 );
if( zTab ){
if( pItem->zAlias ){
char *zTabName = pItem->zAlias;
if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
}else{
char *zTabName = pTab->zName;
if( zTabName==0 || sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
if( zDb!=0 && sqlite3StrICmp(db->aDb[pTab->iDb].zName, zDb)!=0 ){
continue;
}
}
}
}
if( 0==(cntTab++) ){
pExpr->iTable = pItem->iCursor;
pExpr->iDb = pTab->iDb;
pMatch = pItem;
}
for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
cnt++;
if( 0==(cntTab++) ){
pExpr->iTable = pItem->iCursor;
pMatch = pItem;
pExpr->iDb = pTab->iDb;
/* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
pExpr->iColumn = j==pTab->iPKey ? -1 : j;
pExpr->affinity = pTab->aCol[j].affinity;
pExpr->pColl = pTab->aCol[j].pColl;
break;
pMatch = pItem;
}
for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
cnt++;
pExpr->iTable = pItem->iCursor;
pMatch = pItem;
pExpr->iDb = pTab->iDb;
/* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
pExpr->iColumn = j==pTab->iPKey ? -1 : j;
pExpr->affinity = pTab->aCol[j].affinity;
pExpr->pColl = pTab->aCol[j].pColl;
break;
}
}
}
}
@@ -926,7 +930,7 @@ static int lookupName(
pExpr->pRight = 0;
pExpr->op = TK_COLUMN;
if( cnt==1 ){
assert( pNC!=0 && pNC->pSrcList!=0 );
assert( pNC!=0 );
sqlite3AuthRead(pParse, pExpr, pNC->pSrcList);
}
return cnt!=1;
@@ -991,10 +995,11 @@ static int nameResolverStep(void *pArg, Expr *pExpr){
SrcList *pSrcList;
Parse *pParse;
if( pExpr==0 ) return 1;
assert( pNC!=0 );
pSrcList = pNC->pSrcList;
pParse = pNC->pParse;
if( pExpr==0 ) return 1;
if( ExprHasAnyProperty(pExpr, EP_Resolved) ) return 1;
ExprSetProperty(pExpr, EP_Resolved);
#ifndef NDEBUG
@@ -1017,7 +1022,6 @@ static int nameResolverStep(void *pArg, Expr *pExpr){
/* A lone identifier is the name of a column.
*/
case TK_ID: {
if( pSrcList==0 ) break;
lookupName(pParse, 0, 0, &pExpr->token, pNC, pExpr);
return 1;
}
@@ -1031,7 +1035,7 @@ static int nameResolverStep(void *pArg, Expr *pExpr){
Token *pDb;
Expr *pRight;
if( pSrcList==0 ) break;
/* if( pSrcList==0 ) break; */
pRight = pExpr->pRight;
if( pRight->op==TK_ID ){
pDb = 0;
@@ -1052,7 +1056,6 @@ static int nameResolverStep(void *pArg, Expr *pExpr){
case TK_CTIME:
case TK_CTIMESTAMP:
case TK_CDATE:
/* Note: The above three were a seperate case in sqlmoto. Reason? */
case TK_GLOB:
case TK_LIKE:
case TK_FUNCTION: {
@@ -1105,13 +1108,24 @@ static int nameResolverStep(void *pArg, Expr *pExpr){
*/
return is_agg;
}
#ifndef SQLITE_OMIT_SUBQUERY
case TK_SELECT:
case TK_EXISTS:
#endif
case TK_IN: {
if( pExpr->pSelect ){
int nRef = pNC->nRef;
sqlite3SelectResolve(pParse, pExpr->pSelect, pNC);
assert( pNC->nRef>=nRef );
if( nRef!=pNC->nRef ){
ExprSetProperty(pExpr, EP_VarSelect);
}
}
}
}
return 0;
}
/* Forward declaration */
static int sqlite3ExprCodeSubquery(Parse*, NameContext*, Expr*);
/*
** This routine walks an expression tree and resolves references to
** table columns. Nodes of the form ID.ID or ID resolve into an
@@ -1134,31 +1148,13 @@ static int sqlite3ExprCodeSubquery(Parse*, NameContext*, Expr*);
** property on the expression.
*/
int sqlite3ExprResolveNames(
Parse *pParse, /* The parser context */
SrcList *pSrcList, /* List of tables used to resolve column names */
ExprList *pEList, /* List of expressions used to resolve "AS" */
NameContext *pNC, /* Namespace of enclosing statement */
Expr *pExpr, /* The expression to be analyzed. */
int allowAgg, /* True to allow aggregate expressions */
int codeSubquery /* If true, then generate code for subqueries too */
NameContext *pNC, /* Namespace to resolve expressions in. */
Expr *pExpr /* The expression to be analyzed. */
){
NameContext sNC;
if( pExpr==0 ) return 0;
memset(&sNC, 0, sizeof(sNC));
sNC.pSrcList = pSrcList;
sNC.pParse = pParse;
sNC.pEList = pEList;
sNC.allowAgg = allowAgg;
sNC.pNext = pNC;
walkExprTree(pExpr, nameResolverStep, &sNC);
if( sNC.hasAgg ){
ExprSetProperty(pExpr, EP_Agg);
}
if( sNC.nErr>0 ){
walkExprTree(pExpr, nameResolverStep, pNC);
if( pNC->nErr>0 ){
ExprSetProperty(pExpr, EP_Error);
}else if( codeSubquery && sqlite3ExprCodeSubquery(pParse, &sNC, pExpr) ){
return 1;
}
return ExprHasProperty(pExpr, EP_Error);
}
@@ -1186,28 +1182,36 @@ struct QueryCoder {
** The first form is handled by creating a set holding the list
** of allowed values. The second form causes the SELECT to generate
** a temporary table.
**
** This routine also looks for scalar SELECTs that are part of an expression.
** If it finds any, it generates code to write the value of that select
** into a memory cell.
**
** This routine is a callback for wallExprTree() used to implement
** sqlite3ExprCodeSubquery(). See comments on those routines for
** additional information.
*/
#ifndef SQLITE_OMIT_SUBQUERY
static int codeSubqueryStep(void *pArg, Expr *pExpr){
QueryCoder *pCoder = (QueryCoder*)pArg;
Parse *pParse = pCoder->pParse;
void sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){
int label = 0; /* Address after sub-select code */
Vdbe *v = sqlite3GetVdbe(pParse);
if( v==0 ) return;
/* If this is not a variable (correlated) select, then execute
** it only once. Unless this is part of a trigger program. In
** that case re-execute every time (this could be optimized).
*/
if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
int mem = pParse->nMem++;
sqlite3VdbeAddOp(v, OP_MemLoad, mem, 0);
label = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp(v, OP_If, 0, label);
sqlite3VdbeAddOp(v, OP_Integer, 1, 0);
sqlite3VdbeAddOp(v, OP_MemStore, mem, 1);
}
if( pExpr->pSelect ){
sqlite3VdbeAddOp(v, OP_AggContextPush, 0, 0);
}
switch( pExpr->op ){
case TK_IN: {
char affinity;
Vdbe *v = sqlite3GetVdbe(pParse);
KeyInfo keyInfo;
int addr; /* Address of OP_OpenTemp instruction */
if( v==0 ) return 2;
affinity = sqlite3ExprAffinity(pExpr->pLeft);
/* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
@@ -1238,7 +1242,7 @@ static int codeSubqueryStep(void *pArg, Expr *pExpr){
int iParm = pExpr->iTable + (((int)affinity)<<16);
ExprList *pEList;
assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
sqlite3Select(pParse, pExpr->pSelect, SRT_Set, iParm, 0, 0, 0, 0, 0);
sqlite3Select(pParse, pExpr->pSelect, SRT_Set, iParm, 0, 0, 0, 0);
pEList = pExpr->pSelect->pEList;
if( pEList && pEList->nExpr>0 ){
keyInfo.aColl[0] = binaryCompareCollSeq(pParse, pExpr->pLeft,
@@ -1266,10 +1270,7 @@ static int codeSubqueryStep(void *pArg, Expr *pExpr){
if( !sqlite3ExprIsConstant(pE2) ){
sqlite3ErrorMsg(pParse,
"right-hand side of IN operator must be constant");
return 2;
}
if( sqlite3ExprResolveNames(pParse, 0, 0, 0, pE2, 0, 0) ){
return 2;
return;
}
/* Evaluate the expression and insert it into the temp table */
@@ -1280,7 +1281,7 @@ static int codeSubqueryStep(void *pArg, Expr *pExpr){
}
}
sqlite3VdbeChangeP3(v, addr, (void *)&keyInfo, P3_KEYINFO);
return 1;
break;
}
case TK_EXISTS:
@@ -1289,18 +1290,9 @@ static int codeSubqueryStep(void *pArg, Expr *pExpr){
** value of this select in a memory cell and record the number
** of the memory cell in iColumn.
*/
NameContext *pNC;
int nRef;
Vdbe *v;
int addr;
int sop;
Select *pSel;
pNC = pCoder->pNC;
if( pNC ) nRef = pNC->nRef;
sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
v = sqlite3GetVdbe(pParse);
addr = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
pExpr->iColumn = pParse->nMem++;
pSel = pExpr->pSelect;
if( pExpr->op==TK_SELECT ){
@@ -1312,42 +1304,21 @@ static int codeSubqueryStep(void *pArg, Expr *pExpr){
pSel->pEList = sqlite3ExprListAppend(0,
sqlite3Expr(TK_INTEGER, 0, 0, &one), 0);
}
sqlite3Select(pParse, pSel, sop, pExpr->iColumn, 0, 0, 0, 0, pNC);
if( pNC && pNC->nRef>nRef ){
/* Subquery value changes. Evaluate at each use */
pExpr->iTable = addr+1;
sqlite3VdbeAddOp(v, OP_Return, 0, 0);
sqlite3VdbeChangeP2(v, addr, sqlite3VdbeCurrentAddr(v));
}else{
/* Subquery value is constant. evaluate only once. */
pExpr->iTable = -1;
sqlite3VdbeChangeP2(v, addr, addr+1);
}
return 1;
sqlite3Select(pParse, pSel, sop, pExpr->iColumn, 0, 0, 0, 0);
break;
}
}
return 0;
if( pExpr->pSelect ){
sqlite3VdbeAddOp(v, OP_AggContextPop, 0, 0);
}
if( label<0 ){
sqlite3VdbeResolveLabel(v, label);
}
return;
}
#endif /* SQLITE_OMIT_SUBQUERY */
/*
** Generate code to evaluate subqueries and IN operators contained
** in expression pExpr.
*/
static int sqlite3ExprCodeSubquery(
Parse *pParse, /* Parser */
NameContext *pNC, /* First enclosing namespace. Often NULL */
Expr *pExpr /* Subquery to be coded */
){
#ifndef SQLITE_OMIT_SUBQUERY
QueryCoder sCoder;
sCoder.pParse = pParse;
sCoder.pNC = pNC;
walkExprTree(pExpr, codeSubqueryStep, &sCoder);
#endif
return 0;
}
/*
** Generate an instruction that will put the integer describe by
** text z[0..n-1] on the stack.
@@ -1556,10 +1527,7 @@ void sqlite3ExprCode(Parse *pParse, Expr *pExpr){
#ifndef SQLITE_OMIT_SUBQUERY
case TK_EXISTS:
case TK_SELECT: {
if( pExpr->iTable>=0 ){
sqlite3VdbeAddOp(v, OP_Gosub, 0, pExpr->iTable);
VdbeComment((v, "# run subquery"));
}
sqlite3CodeSubselect(pParse, pExpr);
sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
VdbeComment((v, "# load subquery result"));
break;
@@ -1567,6 +1535,7 @@ void sqlite3ExprCode(Parse *pParse, Expr *pExpr){
case TK_IN: {
int addr;
char affinity;
sqlite3CodeSubselect(pParse, pExpr);
/* Figure out the affinity to use to create a key from the results
** of the expression. affinityStr stores a static string suitable for