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Date: Thu, 12 Oct 2006 05:39:47 -0400
From: Joe <dev@freedomcircle.net>
Subject: Re: Is this a bug? Deleting a column deletes the constraint.
In-reply-to: <2323.1160630748@sss.pgh.pa.us>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Bryce Nesbitt <bryce1@obviously.com>, pgsql-sql@postgresql.org
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On Thu, 2006-10-12 at 01:25 -0400, Tom Lane wrote:
> It does seem like this is wrong, in view of SQL92's statement about
> ALTER TABLE DROP COLUMN:
> 
>          4) If RESTRICT is specified, then C shall not be referenced in
>             the <query expression> of any view descriptor or in the <search
>             condition> of any constraint descriptor other than a table con-
>             straint descriptor that contains references to no other column
>             and that is included in the table descriptor of T.
> 
> IOW we should only allow unique constraints to be auto-dropped if
> they reference just the one single column.  Ick.

I didn't realize before that you can also drop all columns, leaving a
table without *any* columns.  Is that a SQL92 "feature"?

Joe