database/sqlite
1
0
Fork 0
mirror of https://github.com/sqlite/sqlite.git synced 2025-11-14 00:22:38 +03:00
Code Activity

Further modifications to do with ORDER BY and compound SELECT queries. Related to ticket #2822. (CVS 4606)

Browse Source 
FossilOrigin-Name: 0d9b0e6e3a8f8a66956878084085842e94c3cb2f
This commit is contained in:
danielk1977
2007-12-10 18:51:47 +00:00
parent 6ed4b78123
commit 70517ab9a1
5 changed files with 166 additions and 82 deletions
Download Patch File Download Diff File Expand all files Collapse all files

120
src/select.c
View File

@@ -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 1.364 2007/12/08 21:10:20 drh Exp $
** $Id: select.c,v 1.365 2007/12/10 18:51:48 danielk1977 Exp $
*/
#include "sqliteInt.h"
@@ -1412,15 +1412,6 @@ static int prepSelectStmt(Parse *pParse, Select *p){
return rc;
}
/*
** During the process of matching ORDER BY terms to columns of the
** result set, the Exprlist.a[].done flag can be set to one of the
** following values:
*/
#define ORDERBY_MATCH_NONE 0 /* No match found */
#define ORDERBY_MATCH_PARTIAL 1 /* A good match, but not perfect */
#define ORDERBY_MATCH_EXACT 2 /* An exact match seen */
#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** This routine associates entries in an ORDER BY expression list with
@@ -1429,9 +1420,6 @@ static int prepSelectStmt(Parse *pParse, Select *p){
** the top-level node is filled in with column number and the iTable
** value of the top-level node is filled with iTable parameter.
**
** If there are prior SELECT clauses, they are processed first. A match
** in an earlier SELECT takes precedence over a later SELECT.
**
** Any entry that does not match is flagged as an error. The number
** of errors is returned.
*/
@@ -1439,91 +1427,83 @@ static int matchOrderbyToColumn(
Parse *pParse, /* A place to leave error messages */
Select *pSelect, /* Match to result columns of this SELECT */
ExprList *pOrderBy, /* The ORDER BY values to match against columns */
int iTable, /* Insert this value in iTable */
int rightMost /* TRUE for outermost recursive invocation */
int iTable /* Insert this value in iTable */
){
int nErr = 0;
int i, j;
ExprList *pEList;
sqlite3 *db = pParse->db;
NameContext nc;
int nExpr;
if( pSelect==0 || pOrderBy==0 ) return 1;
if( rightMost ){
assert( pSelect->pOrderBy==pOrderBy );
for(i=0; i<pOrderBy->nExpr; i++){
pOrderBy->a[i].done = ORDERBY_MATCH_NONE;
}
}
if( pSelect->pPrior
&& matchOrderbyToColumn(pParse, pSelect->pPrior, pOrderBy, iTable, 0) ){
return 1;
}
if( sqlite3SelectResolve(pParse, pSelect, 0) ){
return 1;
}
memset(&nc, 0, sizeof(nc));
nc.pParse = pParse;
nc.pSrcList = pSelect->pSrc;
nc.pEList = pEList = pSelect->pEList;
nc.allowAgg = 1;
nExpr = pSelect->pEList->nExpr;
for(i=0; nErr==0 && i<pOrderBy->nExpr; i++){
struct ExprList_item *pItem;
Expr *pE = pOrderBy->a[i].pExpr;
int iCol = -1;
int match = ORDERBY_MATCH_NONE;
Expr *pDup;
if( pOrderBy->a[i].done==ORDERBY_MATCH_EXACT ){
continue;
}
if( sqlite3ExprIsInteger(pE, &iCol) ){
if( iCol<=0 || iCol>pEList->nExpr ){
if( iCol<=0 || iCol>nExpr ){
sqlite3ErrorMsg(pParse,
"ORDER BY position %d should be between 1 and %d",
iCol, pEList->nExpr);
iCol, nExpr);
nErr++;
break;
}
if( !rightMost ) continue;
iCol--;
match = ORDERBY_MATCH_EXACT;
}
if( !match && pParse->nErr==0 && (pDup = sqlite3ExprDup(db, pE))!=0 ){
nc.nErr = 0;
assert( pParse->zErrMsg==0 );
if( sqlite3ExprResolveNames(&nc, pDup) ){
sqlite3ErrorClear(pParse);
}else{
for(j=0, pItem=pEList->a; j<pEList->nExpr; j++, pItem++){
if( sqlite3ExprCompare(pItem->pExpr, pDup) ){
iCol = j;
match = ORDERBY_MATCH_PARTIAL;
break;
}else{
Select *p;
for(p=pSelect; p; p=p->pPrior){
ExprList *pEList = p->pEList;
Expr *pDup = sqlite3ExprDup(db, pE);
NameContext nc;
memset(&nc, 0, sizeof(nc));
nc.pParse = pParse;
nc.pSrcList = p->pSrc;
nc.pEList = pEList;
nc.allowAgg = 1;
nc.nErr = 0;
if( sqlite3ExprResolveNames(&nc, pDup) ){
sqlite3ErrorClear(pParse);
}else{
struct ExprList_item *pItem;
for(j=0, pItem=pEList->a; j<pEList->nExpr; j++, pItem++){
if( sqlite3ExprCompare(pItem->pExpr, pDup) ){
if( iCol>=0 && iCol!=j ){
sqlite3ErrorMsg(
pParse, "ORDER BY term number %d is ambiguous", i+1
);
}else{
iCol = j;
}
}
}
}
sqlite3ExprDelete(pDup);
}
sqlite3ExprDelete(pDup);
}
if( match ){
if( iCol<0 ){
sqlite3ErrorMsg(pParse,
"ORDER BY term number %d does not match any result column", i+1);
}else{
pE->op = TK_COLUMN;
pE->iTable = iTable;
pE->iAgg = -1;
if( pOrderBy->a[i].done!=ORDERBY_MATCH_NONE && pE->iColumn!=iCol ){
sqlite3ErrorMsg(pParse,
"ORDER BY term number %d is ambiguous", i+1);
nErr++;
}
pE->iColumn = iCol;
pOrderBy->a[i].done = match;
}else if( rightMost && pOrderBy->a[i].done==ORDERBY_MATCH_NONE ){
sqlite3ErrorMsg(pParse,
"ORDER BY term number %d does not match any result column", i+1);
nErr++;
break;
pOrderBy->a[i].done = 1;
}
if( pParse->nErr ){
return pParse->nErr;
}
}
return nErr;
return SQLITE_OK;
}
#endif /* #ifndef SQLITE_OMIT_COMPOUND_SELECT */
@@ -1788,7 +1768,7 @@ static int multiSelect(
** intermediate results.
*/
unionTab = pParse->nTab++;
if( pOrderBy && matchOrderbyToColumn(pParse, p, pOrderBy, unionTab,1) ){
if( pOrderBy && matchOrderbyToColumn(pParse, p, pOrderBy, unionTab) ){
rc = 1;
goto multi_select_end;
}
@@ -1885,7 +1865,7 @@ static int multiSelect(
*/
tab1 = pParse->nTab++;
tab2 = pParse->nTab++;
if( pOrderBy && matchOrderbyToColumn(pParse,p,pOrderBy,tab1,1) ){
if( pOrderBy && matchOrderbyToColumn(pParse,p,pOrderBy,tab1) ){
rc = 1;
goto multi_select_end;
}