On Thu, Apr 27, 2017 at 7:53 PM, Marko Tiikkaja <marko@joh.to> wrote:
> On Thu, Apr 27, 2017 at 4:13 PM, Bruce Momjian <bruce@momjian.us> wrote:
>>
>> On Thu, Apr 27, 2017 at 08:00:28AM +0530, Amit Kapila wrote:
>> > > Oh, so non-correlated subqueries can be run in parallel. Yes, that is
>> > > something we should have in the release notes. How is this?
>> > >
>> > > Author: Robert Haas <rhaas@postgresql.org>
>> > > 2017-02-14 [5e6d8d2bb] Allow parallel workers to execute
>> > > subplans.
>> > >
>> > > Allow non-correlated subqueries to be run in parallel (Amit
>> > > Kapila)
>> > >
>> >
>> > Looks good to me.
>
>
> It's not clear from this item what the previous behavior was. How about
> adding something like "Correlated subqueries can not yet be parallelized."?
> (I'm guessing that's the change, anyway, please correct me if I'm mistaken.)
>
Previous to this change queries containing a reference to subplans
(correlated or un-correlated) doesn't get parallelised.
--
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com