David Rowley <dgrowle...@gmail.com> writes: > On Fri, Sep 12, 2014 at 3:35 AM, Robert Haas <robertmh...@gmail.com> wrote: >> I haven't read the patch, but I think the question is why this needs >> to be different than what we do for left join removal.
> I discovered over here -> > http://www.postgresql.org/message-id/CAApHDvo5wCRk7uHBuMHJaDpbW-b_oGKQOuisCZzHC25=h3_...@mail.gmail.com > during the early days of the semi and anti join removal code that the > planner was trying to generate paths to the dead rel. I managed to track > the problem down to eclass members still existing for the dead rel. I guess > we must not have eclass members for outer rels? or we'd likely have seen > some troubles with left join removals already. Mere existence of an eclass entry ought not cause paths to get built. It'd be worth looking a bit harder into what's happening there. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers