> How many rows do you have in that table? a9-dev=> select count(*) from records; count --------- 3620311 (1 row) a9-dev=> select source_id, count(*) from records where source_id = 'http://ebuw.uw.edu.pl/dlibra/oai-pmh-repository.xml' or source_id = 'http://www.wbc.poznan.pl/dlibra/oai-pmh-repository.xml' group by source_id; source_id | count --------------------------------------------------------+-------- http://ebuw.uw.edu.pl/dlibra/oai-pmh-repository.xml | 427254 http://www.wbc.poznan.pl/dlibra/oai-pmh-repository.xml | 989184 (2 rows) > ALTER TABLE records ALTER id SET source_id 1000; vacuum analyze verbose records; Did you mean ALTER TABLE records ALTER id SET STATISTICS 1000;? Wiadomość napisana przez Gregg Jaskiewicz w dniu 3 paź 2011, o godz. 12:02: > How many rows do you have in that table? > > I think , that planner thinks that the element you are looking for is > so common - that it will be to expensive to use index to fetch it. > Perhaps try increasing default_statistics_target , and revacuuming the table. > > You could also try changing it just for the column: > > ALTER TABLE records ALTER id SET source_id 1000; vacuum analyze verbose records; > > -- > Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
