[postgis-users] When to use Vacuum Analyze

[Sheara Cohen]

Hi -

I'm a relatively new user to PostGIS/Postgres and was told that I should use Vacuum Analyze whenever a I create a new table. I have been discovering, however, that the time it takes to run vacuum analyze on a table is often *MUCH* greater than the time saved during dependent operations.

So, this makes me wonder when it is really critical to run Vacuum Analyze vs. when it is not worth it. (I'm leaning towards not worth it the vast majority of the time.)

For instance, is it important to run AFTER...

*         deleting rows?

*         inserting rows?

*         running st_union?

*         intersecting two geometries?

Or perhaps BEFORE...

*         intersecting two geometries

*         joining two or more tables

*         making row selections and column calculations

Etc...

Thank you!
Sheara

Sheara Cohen
Planner
C A L T H O R P E  A S S O C I A T E S
2095 ROSE STREET, SUITE 201, BERKELEY, CALIFORNIA, 94709 USA
510 809-1165 (direct) | 510-548-6800 x35 (main) | 510 548-6848 (fax)
sheara at calthorpe.com<mailto:sheara at calthorpe.com> | www.calthorpe.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/postgis-users/attachments/20120215/6ec05146/attachment.html>