diff options
Diffstat (limited to 'src/window.c')
| -rw-r--r-- | src/window.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/src/window.c b/src/window.c index 5fb78ce35..a72ec0d2d 100644 --- a/src/window.c +++ b/src/window.c @@ -1279,10 +1279,12 @@ void sqlite3WindowLink(Select *pSel, Window *pWin){ } /* -** Return 0 if the two window objects are identical, or non-zero otherwise. -** Identical window objects can be processed in a single scan. +** Return 0 if the two window objects are identical, 1 if they are +** different, or 2 if it cannot be determined if the objects are identical +** or not. Identical window objects can be processed in a single scan. */ int sqlite3WindowCompare(Parse *pParse, Window *p1, Window *p2, int bFilter){ + int res; if( NEVER(p1==0) || NEVER(p2==0) ) return 1; if( p1->eFrmType!=p2->eFrmType ) return 1; if( p1->eStart!=p2->eStart ) return 1; @@ -1290,10 +1292,16 @@ int sqlite3WindowCompare(Parse *pParse, Window *p1, Window *p2, int bFilter){ if( p1->eExclude!=p2->eExclude ) return 1; if( sqlite3ExprCompare(pParse, p1->pStart, p2->pStart, -1) ) return 1; if( sqlite3ExprCompare(pParse, p1->pEnd, p2->pEnd, -1) ) return 1; - if( sqlite3ExprListCompare(p1->pPartition, p2->pPartition, -1) ) return 1; - if( sqlite3ExprListCompare(p1->pOrderBy, p2->pOrderBy, -1) ) return 1; + if( (res = sqlite3ExprListCompare(p1->pPartition, p2->pPartition, -1)) ){ + return res; + } + if( (res = sqlite3ExprListCompare(p1->pOrderBy, p2->pOrderBy, -1)) ){ + return res; + } if( bFilter ){ - if( sqlite3ExprCompare(pParse, p1->pFilter, p2->pFilter, -1) ) return 1; + if( (res = sqlite3ExprCompare(pParse, p1->pFilter, p2->pFilter, -1)) ){ + return res; + } } return 0; } @@ -1580,7 +1588,7 @@ static void windowAggStep( /* All OVER clauses in the same window function aggregate step must ** be the same. */ - assert( pWin==pMWin || sqlite3WindowCompare(pParse,pWin,pMWin,0)==0 ); + assert( pWin==pMWin || sqlite3WindowCompare(pParse,pWin,pMWin,0)!=1 ); for(i=0; i<nArg; i++){ if( i!=1 || pFunc->zName!=nth_valueName ){ |