Re: Partial aggregates pushdown

On 10/19/21 08:56, Alexander Pyhalov wrote:
> Hi.
> 
> Tomas Vondra писал 2021-10-15 17:56:
>> As for the proposed approach, it's probably good enough for the first
>> version to restrict this to aggregates where the aggregate result is
>> sufficient, i.e. we don't need any new export/import procedures.
>>
>> But it's very unlikely we'd want to restrict it the way the patch does
>> it, i.e. based on aggregate name. That's both fragile (people can
>> create new aggregates with such name) and against the PostgreSQL
>> extensibility (people may implement custom aggregates, but won't be
>> able to benefit from this just because of name).
>>
>> So for v0 maybe, but I think there neeeds to be a way to relax this in
>> some way, for example we could add a new flag to pg_aggregate to mark
>> aggregates supporting this.
>>
> 
> Updated patch to mark aggregates as pushdown-safe in pg_aggregates.
> 
> So far have no solution for aggregates with internal aggtranstype.

Thanks. Please add it to the next CF, so that we don't lose track of it.

regards

-- 
Tomas Vondra
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