On Mon, Aug 23, 2010 at 4:15 AM, Jann Röder <roederja@xxxxxxx> wrote: > Am 23.08.10 07:52, schrieb Scott Marlowe: >> Also are a.indexid and b.indexid the same type? >> > > You mean ItemID? Fields of the same name are of the same type - so yes. > According to the documentation pgsql adds indexes for primary keys > automatically so (b.itemID, b.indexNumber) is indexed. Or do you think > adding an extra idnex for b.itemID alone will help? If I understand the > documentation correctly, pqSQL can use the first column of a > multi-column index as if it was indexed individually... but maybe I'm > wrong here. It can but that doesn't mean it will. A multi-column index is often quite a bit bigger than a single column one. What happens if you try set enable_seqscan=off; (your query here) -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
