Re: optimizing Postgres queries
David Teran <david.teran@cluster9.com>
From: David Teran <david.teran@cluster9.com>
To: Shridhar Daithankar <shridhar_daithankar@myrealbox.com>
Cc: pgsql-performance@postgresql.org
Date: 2004-01-05T12:05:03Z
Lists: pgsql-performance
Hi Shridhar, > Are you sure you are using correct data types on indexes? > Did not know about this... > e.g. if field1 is an int2 field, then following query would not use an > index. > our fk have the type bigint, when i try one simple select like this: explain analyze SELECT --columns-- FROM KEY_VALUE_META_DATA t0 WHERE t0.ID_FOREIGN_TABLE = 21110; i see that no index is being used whereas when i use explain analyze SELECT --columns-- FROM KEY_VALUE_META_DATA t0 WHERE t0.ID_FOREIGN_TABLE = 21110::bigint; an index is used. Very fine, the performance is about 10 to 100 times faster for the single select. I am using WebObjects with JDBC. I will now create a DB with integer instead of bigint and see how this performs. regards David