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From: Josh Berkus <josh@agliodbs.com>
Organization: Aglio Database Solutions
To: "phd9110" <phd9110@cs.nchu.edu.tw>, <pgsql-sql@postgresql.org>
Subject: Re: Index Selection Problem
Date: Thu, 22 May 2003 09:12:36 -0700
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M. Gonfong (or M. Kao?)

> I and my lab is interesting in the index selection problem.
> Is there any index selection tools ( like MS SQL Server index tuning wizard
> ) in postgresql ? Is  there  any project about this problem which is going
> If we want to develop this tool , what document i should read. or where i
> can get more support.

Check out the developer web site:
http://developer.postgresql.org

There is documentation there to give you an overview of the PostgreSQL 
internals.

Unlike SQL Server, PostgreSQL does not permit "index hints" in queries.  
Postgres' philosophy, to date, has been to improve the query planner as much 
as possible and to focus on whole-database tuning tools rather than giving 
users ways to override the planner on a per-query basis. (Am I getting this 
right, Tom?)

That being said, I know the team could use some help in improving the 
planner's behavior, for example in the selectivity of subselects in the WHERE 
clause.  If you are interested in contributing to the project, join the 
PGSQL-HACKERS mailing list and propose your patch there.

-- 
Josh Berkus
Aglio Database Solutions
San Francisco