Tom Lane <tgl@xxxxxxxxxxxxx> schrieb: > "Andrus" <kobruleht2@xxxxxx> writes: > > Index is not used for > > is null > > > How to fix ? > > Update to something newer than 8.1 (specifically, you'll need 8.3). Right. For my example in the other mail: test=*# create index idx_foo on foo(i); CREATE INDEX test=*# explain analyse select * from foo where i is null; QUERY PLAN -------------------------------------------------------------------------------------------------------------------- Bitmap Heap Scan on foo (cost=95.11..4780.49 rows=5000 width=8) (actual time=0.052..0.053 rows=1 loops=1) Recheck Cond: (i IS NULL) -> Bitmap Index Scan on idx_foo (cost=0.00..93.86 rows=5000 width=0) (actual time=0.047..0.047 rows=1 loops=1) Index Cond: (i IS NULL) Total runtime: 0.076 ms Andreas -- Really, I'm not out to destroy Microsoft. That will just be a completely unintentional side effect. (Linus Torvalds) "If I was god, I would recompile penguin with --enable-fly." (unknown) Kaufbach, Saxony, Germany, Europe. N 51.05082°, E 13.56889° -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance