Re: Avg performance for int8/numeric

From: Bruce Momjian <bruce(at)momjian(dot)us>
To: Mark Kirkwood <markir(at)paradise(dot)net(dot)nz>
Cc: Neil Conway <neilc(at)samurai(dot)com>, PostgreSQL-patches <pgsql-patches(at)postgresql(dot)org>, "eng(at)intranet(dot)greenplum(dot)com" <eng(at)intranet(dot)greenplum(dot)com>
Subject: Re: Avg performance for int8/numeric
Date: 2007-02-17 00:56:01
Message-ID: 200702170056.l1H0u1D18396@momjian.us
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-patches


Patch applied. Thanks.

---------------------------------------------------------------------------

Mark Kirkwood wrote:
> Bruce Momjian wrote:
> > I have tested this patch but it generates regression failures.
> >
> > There was some code drift, so I am attaching an updated version of the
> > patch, and the regression diffs. The 'four' column is an 'int4' so my
> > guess is that somehow the wrong aggregate is being called.
> >
>
> Good catch - I must have neglected to run the regression test after
> amending the number of array arguments for the numeric avg :-(.
>
> Hmmm - this changing the number of array args for avg means we can't mix
> transition functions for variance with final functions for avg - which
> is exactly what the regression suite does with the 'newavg' aggregate.
>
> I've 'fixed' this by amending the definition of 'newavg' to use the
> transition and final function that 'avg' does. However I found myself
> asking if this lost us the point of that test - so I looked back at the
> older postgres versions (e.g. 7.1.3) and saw that back *then* 'newavg'
> and 'avg' were defined using the same functions...so I think making the
> change as indicated is ok.
>
> I've attached a new patch with this change.
>
> Cheers
>
> Mark

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Bruce Momjian 2007-02-17 01:05:18 8.3 patches hold queue empty
Previous Message Bruce Momjian 2007-02-17 00:23:41 Re: Avg performance for int8/numeric

Browse pgsql-patches by date

  From Date Subject
Next Message Bruce Momjian 2007-02-17 01:06:55 Re: [pgsql-patches] [PATCHES] [Fwd: Index Advisor]
Previous Message Alvaro Herrera 2007-02-17 00:37:03 Re: [GENERAL] ISO week dates