Re: Parallel Aggregates for string_agg and array_agg

On 2 May 2018 at 10:14, David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> wrote:
> On 2 May 2018 at 08:59, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> My estimate for the number of people positively impacted could be off
>> by a factor of a thousand, and it still wouldn't change the conclusion
>> that this will hurt more people than it helps.
>
> It's probably best to have this argument again in 6 months or so.
> Someone might decide to put some effort into teaching the planner
> about ordered aggregates so it can choose to provide pre-sorted input
> to aggregate functions so that nodeAgg.c no longer has to perform the
> costly explicit sorts.

It seems unlikely that ordered aggregates will be fixed in the July
'fest or even any time soon, so I'm going to mark this patch as
returned with feedback in aid of slightly reducing the patch list.

I'll submit it again when there more consensus that we want this.

Thanks for all the reviews.

--
David Rowley http://www.2ndQuadrant.com/
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