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From: Tom Lane <tgl@sss.pgh.pa.us>
To: chetansuttraway@gmail.com
cc: pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #17162: order by clause is not pushed down to foreign scans
 when a WHERE clause is given in query
In-reply-to: <17162-d69d57bc36cb53f5@postgresql.org>
References: <17162-d69d57bc36cb53f5@postgresql.org>
Comments: In-reply-to PG Bug reporting form <noreply@postgresql.org>
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Date: Thu, 26 Aug 2021 10:11:22 -0400
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PG Bug reporting form <noreply@postgresql.org> writes:
> Wouldn't it be good to push order by clause even when where clause is given
> in query?

Maybe, but you haven't demonstrated it.  In the example you show,
the query plan still requires a local sort, so pre-sorting the
individual inputs to that would just add cycles without accomplishing
anything.

In any case, this is not a bug.

			regards, tom lane