From: Tom Lane <tgl@sss.pgh.pa.us>
To: Wells Oliver <wells.oliver@gmail.com>
cc: pgsql-admin <pgsql-admin@postgresql.org>
Subject: Re: Temp table + inde + FDW table on Redshift: MOVE BACKWARD ALL IN
 not supported
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References: 
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Comments: In-reply-to Wells Oliver <wells.oliver@gmail.com>
	message dated "Sat, 10 Feb 2024 15:35:53 -0800"
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Date: Sat, 10 Feb 2024 19:20:54 -0500
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Wells Oliver <wells.oliver@gmail.com> writes:
> Hi all. This might be a Redshift-specific issue and if so, I apologize for
> posting here, but there might be something more general with FDW, indexes,
> and temp tables going on too, so I thought I'd post.
> ...
> The query runs for a split second, you can see some results, and then bombs:

> ERROR:  SQL command "MOVE BACKWARD ALL IN c1" not supported.
> CONTEXT:  remote SQL command: MOVE BACKWARD ALL IN c1

You didn't show an EXPLAIN, but it looks like the FDW is expecting
the remote server to support something it doesn't.  I'd guess that
you need a Redshift-specific FDW to make this work reliably.  You
could possibly work around it by forcing the planner to use a
different join method.

			regards, tom lane