Re: FW: Query execution failure

Bruce Momjian <bruce@momjian.us>

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From: Bruce Momjian <bruce@momjian.us>

To: Tom Lane <tgl@sss.pgh.pa.us>

Cc: Pete Storer <Pete.Storer@sas.com>, "pgsql-bugs@lists.postgresql.org" <pgsql-bugs@lists.postgresql.org>

Date: 2023-09-28T01:00:12Z

Lists: pgsql-bugs

Attachments

fdw.diff (text/x-diff) patch

On Mon, Jan 30, 2023 at 10:34:20AM -0500, Bruce Momjian wrote:
> On Thu, Jan 26, 2023 at 11:06:41AM -0500, Tom Lane wrote:
> > I don't know anything about the mysql FDW, but another possible route
> > to fixing things is to get it to not believe that the remote's sort
> > ordering matches the local one.  If the plan were relying on a local
> > sort instead of a remote sort then everything would be fine.
> 
> When we implemented sort pushdown to FDWs I had not considered how hard
> it might be to match sort ordering, especially considering the problem
> we have in matching orderings from different operating system versions.
> 
> Is this documented somewhere?

The attached patch documents this remote sort order requirement.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EDB                                      https://enterprisedb.com

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