AFAIK, There is code to remove the redundant relations (joins too are relations). But I don't remember exactly where it is. Start looking at query_planner(). The removal of relations should happen before actually planning the joins.
On Tue, Jul 9, 2013 at 12:21 PM, Atri Sharma <atri.j...@gmail.com> wrote: > My main point here is researching how difficult it is to add > functionality in the planner to allow it to to detect and make > decisions on foreign keys present in the outer relation. > > I think that if this is added, rest of the work would be much easier. > I amy be completely wrong,though. > > Thoughts/Comments? > > Regards, > > Atri > > Regards, > > Atri > l'apprenant > > > -- > Sent via pgsql-hackers mailing list (firstname.lastname@example.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers > -- Best Wishes, Ashutosh Bapat EntepriseDB Corporation The Postgres Database Company