Re: [HACKERS] Parallel Aggregation support for aggregate functionsthat use transitions not implemented for array_agg - Mailing list pgsql-hackers

From Robert Haas
Subject Re: [HACKERS] Parallel Aggregation support for aggregate functionsthat use transitions not implemented for array_agg
Date
Msg-id CA+TgmoYnQ4e2_6bSxCTs5=AkiVLaOs7qSFtrHdqm0=1Bv2i+zA@mail.gmail.com
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In response to Re: [HACKERS] Parallel Aggregation support for aggregate functionsthat use transitions not implemented for array_agg  (David Fetter <david@fetter.org>)
Responses Re: [HACKERS] Parallel Aggregation support for aggregate functionsthat use transitions not implemented for array_agg  (Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>)
List pgsql-hackers
On Tue, Jun 6, 2017 at 3:23 PM, David Fetter <david@fetter.org> wrote:
> I'd bet on lack of tuits.

I expect that was part of it.  Another thing to consider is that, for
numeric aggregates, the transition values don't generally get larger
as you aggregate, but for something like string_agg(), they will.
It's not clear how much work we'll really save by parallelizing that
sort of thing.  Maybe it will be great?

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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