Re: Parallel Aggregates for string_agg and array_agg - Mailing list pgsql-hackers

On 03/29/2018 05:49 AM, David Rowley wrote:
> On 29 March 2018 at 03:05, Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote:
>> On 03/28/2018 03:54 PM, Tom Lane wrote:
>>> I had in mind to look at exprType() of the argument.
>>
>> Right, I'm fine with that.
> 
> Attached is v9, which is based on Tom's v8 but includes the new tests
> and I think the required fix to disable use of the serial/deserial
> function for array_agg().
> 

I have only looked at the diff, but it seems fine to me (in the sense
that it's doing the right checks to disable parallelism only when really
needed).

FWIW I wonder if we might simply fallback to input/output functions when
the send/receive functions are not available. Not sure it's worth it.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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