Re: Rethinking representation of partial-aggregate steps - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Rethinking representation of partial-aggregate steps
Date
Msg-id 16106.1466972912@sss.pgh.pa.us
Whole thread Raw
In response to Re: Rethinking representation of partial-aggregate steps  (David Rowley <david.rowley@2ndquadrant.com>)
Responses Re: Rethinking representation of partial-aggregate steps  (Tom Lane <tgl@sss.pgh.pa.us>)
Re: Rethinking representation of partial-aggregate steps  (David Rowley <david.rowley@2ndquadrant.com>)
List pgsql-hackers
David Rowley <david.rowley@2ndquadrant.com> writes:
> On 27 June 2016 at 03:36, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Looking at this in the light of morning, I'm rather strongly tempted to
>> invert the sense of the FINALIZE option, so that "simple" mode works out
>> as zero, ie, select no options.  Maybe call it SKIPFINAL instead of
>> FINALIZE?

> Aggref calls this aggpartial, and I was tempted to invert that many
> times and make it aggfinalize, but in the end didn't.
> It seems nicer to me to keep it as a list of things that are done,
> rather than to make one exception to that just so we can have the
> simple mode as 0.

[ shrug... ]  I do not buy that argument, because it doesn't justify
the COMBINE option: why shouldn't that be inverted, ie USEFINALFUNC?
The only way to decide that except by fiat is to say that we're
enumerating the non-default or non-simple-mode behaviors.
        regards, tom lane



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