Re: Forcing index scan on query produces 16x faster - Mailing list pgsql-performance

From David Wilson
Subject Re: Forcing index scan on query produces 16x faster
Date
Msg-id e7f9235d1003171456q5d905234o85a1843f7a196218@mail.gmail.com
Whole thread Raw
In response to Forcing index scan on query produces 16x faster  (Christian Brink <cbrink@r-stream.com>)
List pgsql-performance


On Wed, Mar 17, 2010 at 5:25 PM, Christian Brink <cbrink@r-stream.com> wrote:

              ->  Index Scan using sales_tranzdate_index on sales s  (cost=0.01..1825.27 rows=22530 width=12) (actual time=0.072..3.464 rows=225 loops=1)

Have you tried increasing the statistics on that table (and then analyzing)? The estimates for that index scan are off by a factor of 100, which may indicate why the planner is trying so hard to avoid a nestloop there.

--
- David T. Wilson
david.t.wilson@gmail.com

pgsql-performance by date:

Previous
From: Christian Brink
Date:
Subject: Forcing index scan on query produces 16x faster
Next
From: Tom Lane
Date:
Subject: Re: Forcing index scan on query produces 16x faster