From: Tom Lane <tgl@sss.pgh.pa.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
cc: Peter Geoghegan <pg@bowt.ie>, Vik Fearing <vik.fearing@2ndquadrant.com>,
        Andrew Gierth <andrew@tao11.riddles.org.uk>,
        PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: Fix for FETCH FIRST syntax problems
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Comments: In-reply-to "David G. Johnston" <david.g.johnston@gmail.com>
	message dated "Sun, 20 May 2018 13:38:18 -0700"
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Date: Sun, 20 May 2018 17:16:45 -0400
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"David G. Johnston" <david.g.johnston@gmail.com> writes:
> ​The risk here is significantly reduced since the existing user-visible
> behavior is an error which presumably no one is relying upon.  Between that
> and being able to conform to the standard syntax for a long-standing
> feature I would say the benefit outweighs the cost and risk.

The risk you're ignoring is that this patch will break something that
*did* work before.  Given that the first version did exactly that,
I do not think that risk should be considered negligible.  I'm going
to change my vote for back-patching from -0.5 to -1.

			regards, tom lane