On Wed, Oct 19, 2016 at 11:07 PM, Amit Kapila <amit.kapila16@gmail.com> wrote:
>> Ideally, the parallel_workers storage parameter will rarely be
>> necessary because the optimizer will generally do the right thing in
>> all case.
>
> Yeah, we can choose not to provide any parameter for parallel index
> scans, but some users might want to have a parameter similar to
> parallel table scans, so it could be handy for them to use.
I think the parallel_workers reloption should override the degree of
parallelism for any sort of parallel scan on that table. Had I
intended it to apply only to sequential scans, I would have named it
differently.
--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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