Re: multiple table scan performance - Mailing list pgsql-performance

From Claudio Freire
Subject Re: multiple table scan performance
Date
Msg-id AANLkTikeXoo4ZRRvLjx23sR1bNSqC9bevA5Cm9iKdvcU@mail.gmail.com
Whole thread Raw
In response to multiple table scan performance  (Samuel Gendler <sgendler@ideasculptor.com>)
List pgsql-performance
On Tue, Mar 29, 2011 at 7:16 PM, Samuel Gendler
<sgendler@ideasculptor.com> wrote:
> Is there any performance benefit to revamping the workload such that it issues
> a single:
> insert into (...) select ... UNION select ... UNION select
> as opposed to 3 separate "insert into () select ..." statements.

I wouldn't expect any difference - if you used UNION ALL (union will
be equivalent to insert into ()  select DISTINCT ...)

pgsql-performance by date:

Previous
From: Samuel Gendler
Date:
Subject: multiple table scan performance
Next
From: Marti Raudsepp
Date:
Subject: Re: multiple table scan performance