On 2016-08-31 19:07:00 +0300, Heikki Linnakangas wrote: > On 08/31/2016 06:51 PM, Andres Freund wrote: > > I've first combined the projection for all the aggregates, ordered set, > > or not, into one projetion. That got rid of a fair amount of overhead > > when you have multiple aggregates. I attached an, probably out of date, > > WIP version of that patch. > > A-ha, I also considered doing just that! I also considered a variant where > we call ExecProject once for all non-ordered aggregates, and a separate > ExecProject() for each ordered one. But just switching back to straight > ExecEvalExprs seemed easier.
The issue is that might, I think, end up iteratively deforming the underlying tuple. The projection machinery takes care of that, if we do it in one go. Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers