Re: [HACKERS] Partition-wise aggregation/grouping

On Thu, Mar 22, 2018 at 10:28 PM, Robert Haas <robertmhaas@gmail.com> wrote:

On Thu, Mar 22, 2018 at 6:15 AM, Jeevan Chalke
<jeevan.chalke@enterprisedb.com> wrote:
> Leeks cleaner now. Thanks for refactoring it.
>
> I have merged these changes and flatten all previuos changes into the main
> patch.

Committed 0001-0005.

  I made a few further modifications.  These were
mostly cosmetic, but with two exceptions:

1. I moved one set_cheapest() call to avoid doing that twice for the
top-level grouped_rel.

2. I removed the logic to set partition properties for grouped_rels.
As far as I can see, there's nothing that needs this.  It would be
important if we wanted subsequent planning stages to be able to do
partition-wise stuff, e.g. when doing window functions or setops, or
at higher query levels.  Maybe we'll have that someday; until then, I
think this is just a waste of cycles.

Changes related to postgres_fdw which allows pushing aggregate on the foreign server is not yet committed. Due to this, we will end up getting an error when we have foreign partitions + aggregation.

Attached 0001 patch here (0006 from my earlier patch-set) which adds support for this and thus will not have any error.

--
Robert Haas
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