From: Tom Lane <tgl@sss.pgh.pa.us>
To: David Rowley <david.rowley@2ndquadrant.com>
cc: Mark Dilger <hornschnorter@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: "SELECT ... FROM DUAL" is not quite as silly as it appears
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Comments: In-reply-to David Rowley <david.rowley@2ndquadrant.com>
	message dated "Tue, 15 Jan 2019 13:11:08 +1300"
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Date: Mon, 14 Jan 2019 19:17:24 -0500
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David Rowley <david.rowley@2ndquadrant.com> writes:
> 1. I don't think having a table named "dual" makes a whole lot of
> sense for a table with a single row.

Well, I borrowed Oracle terminology there ;-)

> (Uppercasing these additions would also make them look less of an aftert=
hought.)

Don't really care, can do.

> I also did a quick benchmark of v6 and found the slowdown to be
> smaller after the change made in build_simple_rel()

Thanks for confirming.  I was not very sure that was worth the extra
few bytes of code space, but if you see a difference too, then it's
probably worthwhile.

			regards, tom lane