On Sat, Dec 6, 2014 at 10:08 PM, Tomas Vondra <t...@fuzzy.cz> wrote: > select a.i, b.i from a join b on (a.i = b.i);
I think the concern is that the inner side might be something more elaborate than a plain table scan, like an aggregate or join. I might be all wet, but my impression is that you can make rescanning arbitrarily expensive if you work at it. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
