On Tue, Jan 19, 2010 at 07:40:00AM +0100, Philippe Lang wrote: > I'm trying to figure out how to use an index on an immutable function > call in order to speed up queries. [..] > Unfortunately, Postgreql does not use the index at all.
Yup, an index isn't going to be very useful in what you're doing. It's arranged the "wrong" way around---you want something in the table itself to compare against. I'd just have another column in the table that stores the result of the function call (use a trigger to keep it up to date) and then create an index on this column if you want/need. -- Sam http://samason.me.uk/ -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
