Tony Capobianco <tcapobianco@xxxxxxxxxxxxxx> writes: > pg_dw=# explain CREATE TABLE ecr_opens with (FILLFACTOR=100) > pg_dw-# as > pg_dw-# select o.emailcampaignid, count(memberid) opencnt > pg_dw-# from openactivity o,ecr_sents s > pg_dw-# where s.emailcampaignid = o.emailcampaignid > pg_dw-# group by o.emailcampaignid; > QUERY > PLAN > ------------------------------------------------------------------------------------------------------------- > GroupAggregate (cost=0.00..1788988.05 rows=9939 width=12) > -> Nested Loop (cost=0.00..1742467.24 rows=9279316 width=12) > -> Index Scan using ecr_sents_ecid_idx on ecr_sents s > (cost=0.00..38.59 rows=479 width=4) > -> Index Scan using openact_emcamp_idx on openactivity o > (cost=0.00..3395.49 rows=19372 width=12) > Index Cond: (o.emailcampaignid = s.emailcampaignid) > (5 rows) > Should this query be hashing the smaller table on Postgres rather than > using nested loops? Yeah, seems like it. Just for testing purposes, do "set enable_nestloop = 0" and see what plan you get then. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
