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Use of the CROSS keyword in a join prevents table reordering. Ticket #1414. (CVS 2683)

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FossilOrigin-Name: 415b8b24629aa12756d8285c094b5f85d8a8e532
This commit is contained in:
drh
2005-09-10 15:28:09 +00:00
parent f307a4aaf8
commit 3dec223ca0
5 changed files with 26 additions and 20 deletions
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5
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 1.266 2005/09/08 12:57:28 drh Exp $
** $Id: select.c,v 1.267 2005/09/10 15:28:09 drh Exp $
*/
#include "sqliteInt.h"
@@ -73,6 +73,7 @@ Select *sqlite3SelectNew(
** in terms of the following bit values:
**
** JT_INNER
** JT_CROSS
** JT_OUTER
** JT_NATURAL
** JT_LEFT
@@ -98,7 +99,7 @@ int sqlite3JoinType(Parse *pParse, Token *pA, Token *pB, Token *pC){
{ "full", 4, JT_LEFT|JT_RIGHT|JT_OUTER },
{ "outer", 5, JT_OUTER },
{ "inner", 5, JT_INNER },
{ "cross", 5, JT_INNER },
{ "cross", 5, JT_INNER|JT_CROSS },
};
int i, j;
apAll[0] = pA;

13
src/sqliteInt.h
View File

@@ -11,7 +11,7 @@
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.413 2005/09/09 01:33:19 drh Exp $
** @(#) $Id: sqliteInt.h,v 1.414 2005/09/10 15:28:09 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_
@@ -999,11 +999,12 @@ struct SrcList {
** Permitted values of the SrcList.a.jointype field
*/
#define JT_INNER 0x0001 /* Any kind of inner or cross join */
#define JT_NATURAL 0x0002 /* True for a "natural" join */
#define JT_LEFT 0x0004 /* Left outer join */
#define JT_RIGHT 0x0008 /* Right outer join */
#define JT_OUTER 0x0010 /* The "OUTER" keyword is present */
#define JT_ERROR 0x0020 /* unknown or unsupported join type */
#define JT_CROSS 0x0002 /* Explicit use of the CROSS keyword */
#define JT_NATURAL 0x0004 /* True for a "natural" join */
#define JT_LEFT 0x0008 /* Left outer join */
#define JT_RIGHT 0x0010 /* Right outer join */
#define JT_OUTER 0x0020 /* The "OUTER" keyword is present */
#define JT_ERROR 0x0040 /* unknown or unsupported join type */
/*
** For each nested loop in a WHERE clause implementation, the WhereInfo

10
src/where.c
View File

@@ -16,7 +16,7 @@
** so is applicable. Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.169 2005/09/08 14:17:20 drh Exp $
** $Id: where.c,v 1.170 2005/09/10 15:28:09 drh Exp $
*/
#include "sqliteInt.h"
@@ -1425,6 +1425,7 @@ WhereInfo *sqlite3WhereBegin(
pTabItem = pTabList->a;
pLevel = pWInfo->a;
andFlags = ~0;
TRACE(("*** Optimizer Start ***\n"));
for(i=iFrom=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
Index *pIdx; /* Index for FROM table at pTabItem */
int flags; /* Flags asssociated with pIdx */
@@ -1454,12 +1455,14 @@ WhereInfo *sqlite3WhereBegin(
bestNEq = nEq;
bestJ = j;
}
if( (pTabItem->jointype & JT_LEFT)!=0
|| (j>0 && (pTabItem[-1].jointype & JT_LEFT)!=0)
if( (pTabItem->jointype & (JT_LEFT|JT_CROSS))!=0
|| (j>0 && (pTabItem[-1].jointype & (JT_LEFT|JT_CROSS))!=0)
){
break;
}
}
TRACE(("*** Optimizer choose table %d for loop %d\n", bestJ,
pLevel-pWInfo->a));
if( (bestFlags & WHERE_ORDERBY)!=0 ){
*ppOrderBy = 0;
}
@@ -1477,6 +1480,7 @@ WhereInfo *sqlite3WhereBegin(
notReady &= ~getMask(&maskSet, pTabList->a[bestJ].iCursor);
pLevel->iFrom = bestJ;
}
TRACE(("*** Optimizer Finished ***\n"));
/* If the total query only selects a single row, then the ORDER BY
** clause is irrelevant.