From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Andrew Gierth <andrew@tao11.riddles.org.uk>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: SQL-spec incompatibilities in similar_escape() and related stuff
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Fri, 17 May 2019 11:53:52 -0400"
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Date: Fri, 17 May 2019 13:13:02 -0400
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Robert Haas <robertmhaas@gmail.com> writes:
> I think it's pretty clear that the theoretical beauty of being able to
> handle postfix operators is not worth the tangible cost they impose on
> our parser.  We're losing more users as a result of SQL that other
> systems can accept and we cannot than we are gaining by being able to
> support user-defined postfix operators.

I suppose it's possible to make such an argument, but you haven't
actually made one --- just asserted something without providing
evidence.

If we can lay out some concrete gains that justify zapping postfix
operators, I'd be willing to do it.  I agree that it would likely
hurt few users ... but we need to be able to explain to those few
why we broke it.  And show that the benefits outweigh the cost.

			regards, tom lane