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Cc: Stephan Szabo <sszabo@megazone.bigpanda.com>,
	pgsql-docs@postgresql.org
From: Thomas F.O'Connell <tfo@sitening.com>
Subject: Re: EXTRACT Clarification 
Date: Wed, 29 Sep 2004 11:42:26 -0400
To: Tom Lane <tgl@sss.pgh.pa.us>

That seems reasonable, too, although I was interested to learn that 
this (and a few other expressions) weren't actually functions. Whether 
that's actually meaningful for any implementation purposes is 
debatable.

Even if the grammar is changed to allow it, it's probably worth making 
a note of it in SQL compatibility documentation.

Speaking of which, since functions aren't in the SQL Commands 
reference, where the compatibility documentation resides, does anyone 
see value in adding compatibility information to The SQL Language 
section as a whole?

I can contribute what I know, but I don't have a full copy of the spec.

-tfo

On Sep 29, 2004, at 11:32 AM, Tom Lane wrote:

> "Thomas F.O'Connell" <tfo@sitening.com> writes:
>> I'm thinking something like this (with thanks to Stephan):
>
>> Note: EXTRACT is not a true function. SQL defines it as an expression
>> that happens to look similar to a function call.
>
> Rather than documenting this, maybe we should change the grammar to
> allow it?
>
> 			regards, tom lane