On Fri, Dec 14, 2012 at 4:01 PM, AI Rumman <rumman...@gmail.com> wrote: > Does FK Constraint help to improve performance? Or it is only for > maintaining data integrity?
I'm not entirely sure it's taken into account, I think it is, but a FK would tell the planner that every non-null value will produce a row. It seems to think there are a large portion of non-null values that don't. -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance