Hariraman Jayaraj wrote:
> We are using Postgres 8.3 version, in Suse Linux Enterprise Edition
SP1. Our DB total size is around
> 530 GB. we have enabled the setting related to
default_statistics_target. Kindly suggest what will be
> ideal value for default_statistics_target.
>
> We have more than 1000 relations in our db.
This parameter determines how detailed the statistics
gathered with ANALYZE (and autoanalyze) will be.
You need to increase this parameter from its default
value only if the query plans for your statements are
not good and better statistics can improve them.
There is no connection to the size of the database or
the number of tables.
Monitor for statements that take too much time; if
improving the statistics makes them faster, consider
adjusting the parameter (possibly only for a single
column with ALTER TABLE).
If you are concerned about good execution plans,
consider upgrading to a more recent version.
That would be a good idea anyway.
Yours,
Laurenz Albe