From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Dean Gibson (DB Administrator)" <postgresql@mailpen.com>
cc: "pgsql-performance@lists.postgresql.org"
 <pgsql-performance@lists.postgresql.org>
Subject: Re: AWS forcing PG upgrade from v9.6 a disaster
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Comments: In-reply-to "Dean Gibson (DB Administrator)"
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	message dated "Sun, 30 May 2021 21:23:43 -0700"
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Date: Mon, 31 May 2021 00:44:27 -0400
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"Dean Gibson (DB Administrator)" <postgresql@mailpen.com> writes:
> I thought that having a "USING" clause, was semantically equivalent to 
> an "ON" clause with the equalities explicitly stated.  So no, I didn't 
> try that.

USING is not that, or at least not only that ... read the manual.

I'm wondering if what you saw is some side-effect of the aliasing
that USING does.

			regards, tom lane