diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/where.c | 19 |
1 files changed, 7 insertions, 12 deletions
diff --git a/src/where.c b/src/where.c index 347598abc..6a05d0c4d 100644 --- a/src/where.c +++ b/src/where.c @@ -979,18 +979,13 @@ static sqlite3_index_info *allocateIndexInfo( testcase( pTerm->eOperator & WO_ALL ); if( (pTerm->eOperator & ~(WO_EQUIV))==0 ) continue; if( pTerm->wtFlags & TERM_VNULL ) continue; + + /* tag-20191211-002: WHERE-clause constraints are not useful to the + ** right-hand table of a LEFT JOIN. See tag-20191211-001 for the + ** equivalent restriction for ordinary tables. */ if( (pSrc->fg.jointype & JT_LEFT)!=0 && !ExprHasProperty(pTerm->pExpr, EP_FromJoin) - && (pTerm->eOperator & (WO_IS|WO_ISNULL)) ){ - /* An "IS" term in the WHERE clause where the virtual table is the rhs - ** of a LEFT JOIN. Do not pass this term to the virtual table - ** implementation, as this can lead to incorrect results from SQL such - ** as: - ** - ** "LEFT JOIN vtab WHERE vtab.col IS NULL" */ - testcase( pTerm->eOperator & WO_ISNULL ); - testcase( pTerm->eOperator & WO_IS ); continue; } assert( pTerm->u.leftColumn>=(-1) ); @@ -2472,9 +2467,9 @@ static int whereLoopAddBtreeIndex( ** to mix with a lower range bound from some other source */ if( pTerm->wtFlags & TERM_LIKEOPT && pTerm->eOperator==WO_LT ) continue; - /* Do not allow constraints from the WHERE clause to be used by the - ** right table of a LEFT JOIN. Only constraints in the ON clause are - ** allowed */ + /* tag-20191211-001: Do not allow constraints from the WHERE clause to + ** be used by the right table of a LEFT JOIN. Only constraints in the + ** ON clause are allowed. See tag-20191211-002 for the vtab equivalent. */ if( (pSrc->fg.jointype & JT_LEFT)!=0 && !ExprHasProperty(pTerm->pExpr, EP_FromJoin) ){ |