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To: "Christopher Kings-Lynne" <chriskl@familyhealth.com.au>
cc: "Frank Bax" <fbax@sympatico.ca>, pgsql-sql@postgresql.org
Subject: Re: simple? join 
In-reply-to: <GNELIHDDFBOCMGBFGEFOCEAMCBAA.chriskl@familyhealth.com.au> 
References: <GNELIHDDFBOCMGBFGEFOCEAMCBAA.chriskl@familyhealth.com.au>
Comments: In-reply-to "Christopher Kings-Lynne" <chriskl@familyhealth.com.au>
	message dated "Tue, 08 Jan 2002 09:54:29 +0800"
Date: Mon, 07 Jan 2002 22:25:19 -0500
Message-ID: <21174.1010460319@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
X-Archive-Number: 200201/49
X-Sequence-Number: 6140

"Christopher Kings-Lynne" <chriskl@familyhealth.com.au> writes:
>> So, when and if we get around to implementing this particular SQL99
>> feature, what you are suggesting will work.  Right now it doesn't
>> (and I'll wager that darn few other SQL implementations support this
>> feature as yet, either).

> I think MySQL does.

Do they bother to check validity of the column reference at all?
The cheesy way to do this would be not to check; if you referenced a
non-functionally-dependent column, you'd get a randomly chosen element
value with no warning... but for correct queries it would look like
they had support.

			regards, tom lane