On Wed, Apr 26, 2017 at 6:28 AM, Antonin Houska <a...@cybertec.at> wrote: > Attached is a diff that contains both patches merged. This is just to prove my > assumption, details to be elaborated later. The scripts attached produce the > following plan in my environment: > > QUERY PLAN > ------------------------------------------------ > Parallel Finalize HashAggregate > Group Key: b_1.j > -> Append > -> Parallel Partial HashAggregate > Group Key: b_1.j > -> Hash Join > Hash Cond: (b_1.j = c_1.k) > -> Seq Scan on b_1 > -> Hash > -> Seq Scan on c_1 > -> Parallel Partial HashAggregate > Group Key: b_2.j > -> Hash Join > Hash Cond: (b_2.j = c_2.k) > -> Seq Scan on b_2 > -> Hash > -> Seq Scan on c_2
Well, I'm confused. I see that there's a relationship between what Antonin is trying to do and what Jeevan is trying to do, but I can't figure out whether one is a subset of the other, whether they're both orthogonal, or something else. This plan looks similar to what I would expect Jeevan's patch to produce, except i have no idea what "Parallel" would mean in a plan that contains no Gather node. -- 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
