Re: Avg performance for int8/numeric

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.

Yea, I was just looking at this and came to same conclusion.

> 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.

OK, great, will apply.

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

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