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To: Peter Eisentraut <peter_e@gmx.net>
Cc: milimeter@163.com,
	PostgreSQL Development <pgsql-hackers@postgresql.org>
Subject: Re: [GENERAL] Problem about pgsql's column alias 
In-reply-to: <Pine.LNX.4.44.0304160142100.3722-100000@peter.localdomain> 
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Comments: In-reply-to Peter Eisentraut <peter_e@gmx.net>
	message dated "Wed, 16 Apr 2003 15:46:36 +0200"
Date: Wed, 16 Apr 2003 10:16:49 -0400
Message-ID: <17738.1050502609@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Peter Eisentraut <peter_e@gmx.net> writes:
> Allowing column aliases without AS would break nothing.

... except postfix operators, and whatever else happens to get caught in
the crossfire.  And we'll still get complaints because it only works for
identifiers, not for keywords.

Now I'll admit that the postfix-operator issue is probably a red
herring, since "SELECT a + b, ..." should get interpreted as infix +
in any case.  But I think there are other side-effects we have not
fully analyzed yet.  The one-line grammar hack was not intended to
be actually applied, right?  Let's see a complete proposal.

			regards, tom lane