On Wed, Jul 21, 2010 at 1:58 AM, Rob Wultsch <wultsch@xxxxxxxxx> wrote: > On Wed, Jul 21, 2010 at 12:53 AM, A. Kretschmer > <andreas.kretschmer@xxxxxxxxxxxxxx> wrote: >> >> In response to Elias Ghanem : >> > Hi, >> > I have a question concerning the uses of indexes in Postgresql. >> > I red that in PG a query can not use more than one index per table: "a >> > query or >> > data manipulation command can use at most one index per table". >> >> That's not true, but it's true for MySQL, afaik. >> > > That is not true either, though MySQL is less good at using bitmap'ed > indexes. 5.0 can use "merge indexes", Yeah, the biggest problem MySQL has is that it's got a pretty simplistic query planner so it often makes poor choices. Note that PostgreSQL on the other hand, has a much smarter query planner. So it usually makes better choices. But when it makes a wrong one, it can be a doozie. Luckily, reported strange behavior in the query planner is usually fixed pretty quickly. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
