On Sun, Apr 09, 2006 at 20:44:34 -0700, [EMAIL PROTECTED] wrote: > I have a slow sql: > SELECT * FROM mytable WHERE id IN (1,3,5,7,....3k here...); > mytable is about 10k rows. > > if don't use the "IN" clause, it will cost 0,11 second, otherwise it > will cost 2.x second > I guess pg use linear search to deal with IN clause, is there any way > to let pg use other search method with IN clause? (ex.Binary Search or > hash Search)
It would help if you told us what version of Postgres you are running and showed EXPLAIN ANALYZE results for the two queries. I have heard of people getting better speed by loading the constant list into a temp table and then doing a join. Some older versions of Postgres also had problems with large constant lists, so if you are using an old version of Postgres upgrading might help. ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
