Thanks, increasing the statistics did the trick: ALTER TABLE tskjema ALTER species SET STATISTICS 999 Is there a rule of thumb to tell how to set the statistics? Jonas:)) On 4/19/06, Martijn van Oosterhout <kleptog@xxxxxxxxx> wrote: > On Wed, Apr 19, 2006 at 01:53:46PM +0200, Jonas Henriksen wrote: > > Yes, explain analyze looks like this: > > Well, incorrect statistics are definitly the culprit, look: > > > > " -> Index Scan using sskjema_pkey on sskjema s (cost=0.00..3868.95 rows=9738 width=157) (actual time=104.465..208.185 rows=14417 loops=1)" > > 50% off, not bad. > > > " -> Index Scan using speciesix on tskjema t (cost=0.00..6.01 rows=1 width=75) (actual time=0.140..24.594 rows=1703 loops=1)" > > " Index Cond: ((species ~>=~ 'TAGGMAKRELL'::bpchar) AND (species ~<~ 'TAGGMAKRELM'::bpchar))" > > " Filter: (species ~~ 'TAGGMAKRELL%'::text)" > > Youch, 170200% percent off, which explains why it gets wildly bad > timings. Can you increase the statistics on the species column? Check > the docs for how. > -- > Martijn van Oosterhout <kleptog@xxxxxxxxx> http://svana.org/kleptog/ > > From each according to his ability. To each according to his ability to litigate. > > > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.4.1 (GNU/Linux) > > iD8DBQFERigoIB7bNG8LQkwRAhIdAJ9zFw0pkEqctLqHmbPteg7ofrDlEgCfS9ZO > IscpR2d+wW7fzW3OUM3QYvo= > =OewT > -----END PGP SIGNATURE----- > > >
