Date: Wed, 15 Feb 2006 17:06:56 -0500
From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-sql@postgresql.org
Subject: Re: How to force PostgreSQL using an index
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On Wed, Feb 15, 2006 at 04:58:54PM -0500, Daniel Caune wrote:
> Hi,
> 
>  
> 
> Is there a way to force PostgreSQL using an index for a SELECT
> statement?  I just want to confirm that the index PostgreSQL decides to
> use is better than the index I supposed PostgreSQL would use (I already
> analyze the table).

Your best bet is to do 

set enable_indexscan=false;

and then do the EXPLAIN ANALYSE for your select.

You might also find that fiddling with other settings affects the
planner's idea of what would be a good plan.  The planner is
sensitive to what it thinks it knows about your environment.

A

-- 
Andrew Sullivan  | ajs@crankycanuck.ca
If they don't do anything, we don't need their acronym.
		--Josh Hamilton, on the US FEMA