Re: Hinting the planner

From: Shane Ambler <pgsql(at)Sheeky(dot)Biz>
To: Reg Me Please <regmeplease(at)gmail(dot)com>
Cc: pgsql-general(at)postgresql(dot)org
Subject: Re: Hinting the planner
Date: 2008-01-01 13:45:14
Message-ID: 477A43EA.1060706@Sheeky.Biz
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-general

Reg Me Please wrote:
> Hello all.
>
> I have some tables that contain exactly 1 row and that I use for searches with
> JOIN.
>
> Does it make any sense to hint the planner about this?
> If so, how can I send such hints to it?
>

You don't give hints to the planner.

The planner does use statistics gathered from an ANALYZE to generate the
best plan, so if you haven't analyzed your db you will not likely get
the best plans.

see
http://www.postgresql.org/docs/8.2/interactive/sql-analyze.html

and
http://www.postgresql.org/docs/8.2/interactive/sql-vacuum.html

also
http://www.postgresql.org/docs/8.2/interactive/maintenance.html

can explain these tasks in more detail.

If this is insufficient then you can also look at your config file.

--

Shane Ambler
pgSQL (at) Sheeky (dot) Biz

Get Sheeky @ http://Sheeky.Biz

In response to

Responses

Browse pgsql-general by date

  From Date Subject
Next Message Raymond O'Donnell 2008-01-01 14:11:09 Re: CREATE TYPE and pgAdmin III
Previous Message Reg Me Please 2008-01-01 09:38:00 Hinting the planner