Re: : Performance Improvement Strategy

Venkat,

> I see lot of free spaces or free pages in Tables and Indexes. But, I need to
> give an exact calculation on how much space will be reclaimed after VACUUM
> FULL and RE-INDEXING.

At present, there is no way to calculate this precisely.  You can only
estimate, and estimates have significant error factors.  The query which
Marcin linked for you, for example, can be as much as 500% off (although
usually only 50% off).

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com