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Re: Assumptions about the number of parallel workers - Mailing list pgsql-hackers

From Andres Freund
Subject Re: Assumptions about the number of parallel workers
Date
Msg-id 20200206025029.zj7bx7nygtfr53hh@alap3.anarazel.de
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In response to Assumptions about the number of parallel workers  (Antonin Houska <ah@cybertec.at>)
Responses Re: Assumptions about the number of parallel workers
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Hi,

On 2020-02-05 10:50:05 +0100, Antonin Houska wrote:
> I can't figure out why ExecGather/ExecGatherMerge do check whether num_workers
> is non-zero. I think the code would be a bit clearer if these tests were
> replaced with Assert() statements, as the attached patch does.

It's probably related to force_parallel_mode. With that we'll IIRC
generate gather nodes even if num_workers == 0.

Greetings,

Andres Freund

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