Lars Aksel Opsahl <lars.ops...@nibio.no> writes: > In this example I have two tables one with 4 billion rows and another with > 50000 rows and then I try to do a standard simple join between this two > tables and this takes 397391 ms. with this SQL (the query plan is added is > further down)
This particular query would work a lot better if you had an index on nora_bc25_observation (point_uid_ref, epoch), ie both join columns in one index. I get the impression that that ought to be the primary key of the table, which would be an even stronger reason to have a unique index on it. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance