diff options
Diffstat (limited to 'src/backend/access/nbtree/nbtutils.c')
| -rw-r--r-- | src/backend/access/nbtree/nbtutils.c | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/src/backend/access/nbtree/nbtutils.c b/src/backend/access/nbtree/nbtutils.c index 2e896a258f7..f87eadcdec2 100644 --- a/src/backend/access/nbtree/nbtutils.c +++ b/src/backend/access/nbtree/nbtutils.c @@ -325,8 +325,14 @@ _bt_preprocess_keys(IndexScanDesc scan) /* * If = has been specified, all other keys can be eliminated as - * redundant. In case of key > 2 && key == 1 we can set qual_ok - * to false and abandon further processing. + * redundant. If we have a case like key = 1 AND key > 2, we can + * set qual_ok to false and abandon further processing. + * + * We also have to deal with the case of "key IS NULL", which is + * unsatisfiable in combination with any other index condition. + * By the time we get here, that's been classified as an equality + * check, and we've rejected any combination of it with a regular + * equality condition; but not with other types of conditions. */ if (xform[BTEqualStrategyNumber - 1]) { @@ -339,6 +345,13 @@ _bt_preprocess_keys(IndexScanDesc scan) if (!chk || j == (BTEqualStrategyNumber - 1)) continue; + if (eq->sk_flags & SK_SEARCHNULL) + { + /* IS NULL is contradictory to anything else */ + so->qual_ok = false; + return; + } + if (_bt_compare_scankey_args(scan, chk, eq, chk, &test_result)) { |