> capsa=# explain analyze select name from capsa.flatomfilesysentry > where objectid in ( select dstobj from capsa.flatommemberrelation > where srcobj = 'c1c7304a-1fe1-11db-8af7-001143214409'); > > > QUERY PLAN > --------------------------------------------------------------------------------------------------------------------------------- > Nested Loop IN Join (cost=0.00..1386.45 rows=5809 width=14) (actual > time=2.933..101467.463 rows=5841 loops=1) > Join Filter: ("outer".objectid = "inner".dstobj) > -> Seq Scan on flatomfilesysentry (cost=0.00..368.09 rows=5809 > width=30) (actual time=0.007..23.451 rows=5844 loops=1) > -> Seq Scan on flatommemberrelation (cost=0.00..439.05 rows=5842 > width=16) (actual time=0.007..11.790 rows=2922 loops=5844) A loop for an IN indicates that you are using a very old version of PostgreSQL (7.2 or earlier). Please double check that the server is 8.1.3 as you indicated and not just the client. >From psql: select version(); Hmm... Perhaps it is an 8.1.3 server with mergejoin and hashjoin disabled? show enable_mergejoin; show enable_hashjoin; You can try this query syntax: select name from capsa.flatomfilesysentry join capsa.flatommemberrelation on (objectid = dstobj) where srcobj = 'c1c7304a-1fe1-11db-8af7-001143214409'; > Filter: (srcobj = > 'c1c7304a-1fe1-11db-8af7-001143214409'::capsa_sys.uuid) > Total runtime: 101482.256 ms > (6 rows) > > capsa=# select count(*) from capsa.flatommemberrelation ; > count > ------- > 11932 > (1 row) > > capsa=# select count(*) from capsa.flatomfilesysentry ; > count > ------- > 5977 > > > >