On Thu, 2010-10-28 at 12:59 -0700, Ben wrote: > On Oct 28, 2010, at 12:44 PM, Joshua D. Drake wrote: > > > > My tests show you are incorrect: > > > > > > part_test=# explain analyze select * from foo join bar using (i) where > > i=9; > > QUERY > > PLAN > > ------------------------------------------------------------------------------------------------------------------ > > Nested Loop (cost=34.26..106.76 rows=200 width=20) (actual > > time=0.004..0.004 rows=0 loops=1) > > -> Append (cost=0.00..68.50 rows=20 width=12) (actual > > time=0.004..0.004 rows=0 loops=1) > > -> Seq Scan on foo (cost=0.00..34.25 rows=10 width=12) > > (actual time=0.001..0.001 rows=0 loops=1) > > Filter: (i = 9) > > -> Seq Scan on foo_1 foo (cost=0.00..34.25 rows=10 width=12) > > (actual time=0.000..0.000 rows=0 loops=1) > > Filter: (i = 9) > > -> Materialize (cost=34.26..34.36 rows=10 width=12) (never > > executed) > > -> Seq Scan on bar (cost=0.00..34.25 rows=10 width=12) (never > > executed) > > Filter: (i = 9) > > Total runtime: 0.032 ms > > (10 rows) > > strange. my tests don't agree with your tests : Do you have constraint_exclusion turned on? You should verify with show constraint_exclusion (I saw what you wrote below). JD P.S. Blatant plug, you coming to http://www.postgresqlconference.org ? -- PostgreSQL.org Major Contributor Command Prompt, Inc: http://www.commandprompt.com/ - 509.416.6579 Consulting, Training, Support, Custom Development, Engineering http://twitter.com/cmdpromptinc | http://identi.ca/commandprompt -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
