On Thu, 3 Jun 2010, Anj Adu wrote:
http://explain.depesz.com/s/kHa
I'm interested in why the two partitions dev4_act_dy_fact and dev4_act_dy_fact_2010_05_t3 are treated so differently. I'm guessing that the former is the parent and the latter the child table?
When accessing the parent table, Postgres is able to use a bitmap AND index scan, because it has the two indexes dev4_act_dy_dm_nd_indx and dev4_act_dy_dm_cd_indx. Do the child tables have a similar index setup?
Incidentally, you could get even better than a bitmap AND index scan by creating an index on (node_id, thedate) on each table.
random_page_cost=1
I agree with Tomas that this is rarely a useful setting. Matthew -- You can configure Windows, but don't ask me how. -- Bill Gates -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
