diff options
Diffstat (limited to 'src/backend/optimizer/util')
| -rw-r--r-- | src/backend/optimizer/util/plancat.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c index f4f8ac8a763..e880e668cba 100644 --- a/src/backend/optimizer/util/plancat.c +++ b/src/backend/optimizer/util/plancat.c @@ -9,7 +9,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/util/plancat.c,v 1.154 2009/01/07 22:40:49 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/util/plancat.c,v 1.155 2009/02/15 20:16:21 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -939,15 +939,16 @@ has_unique_index(RelOptInfo *rel, AttrNumber attno) /* * Note: ignore partial indexes, since they don't allow us to conclude - * that all attr values are distinct. We don't take any interest in - * expressional indexes either. Also, a multicolumn unique index - * doesn't allow us to conclude that just the specified attr is - * unique. + * that all attr values are distinct, *unless* they are marked predOK + * which means we know the index's predicate is satisfied by the query. + * We don't take any interest in expressional indexes either. Also, a + * multicolumn unique index doesn't allow us to conclude that just the + * specified attr is unique. */ if (index->unique && index->ncolumns == 1 && index->indexkeys[0] == attno && - index->indpred == NIL) + (index->indpred == NIL || index->predOK)) return true; } return false; |