Re: Parallel execution and prepared statements

On Tue, Nov 29, 2016 at 6:24 AM, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> On Tue, Nov 29, 2016 at 4:40 PM, Albe Laurenz <laurenz(dot)albe(at)wien(dot)gv(dot)at> wrote:
>> Amit Kapila wrote:
>>>> But with Tobias' complete patch "make installcheck-world" succeeds.
>>>
>>> Okay. I have looked into patch proposed and found that it will
>>> resolve the regression test problem (Create Table .. AS Execute). I
>>> think it is slightly prone to breakage if tomorrow we implement usage
>>> of EXECUTE with statements other Create Table (like Copy). Have you
>>> registered this patch in CF to avoid loosing track?
>>>
>>> We have two patches (one proposed in this thread and one proposed by
>>> me earlier [1]) and both solves the regression test failure. Unless
>>> there is some better approach, I think we can go with one of these.
>>
>> Tobias did that here: https://commitfest.postgresql.org/12/890/
>>
>> He added your patch as well.
>>
>
> Okay, Thanks.
>
> Robert, do you have any better ideas for this problem?

Not really. I think your prepared_stmt_parallel_query_v2.patch is
probably the best approach proposed so far, but I wonder why we need
to include DestCopyOut and DestTupleStore. DestIntoRel and
DestTransientRel both write to an actual relation, which is a problem
for parallel mode, but I think the others don't.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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