Re: How to ensure data consistency?

From: Felix E. Klee <felix.klee_at_inka.de>
Date: Fri, 10 Sep 2004 01:59:21 +0200
Message-ID: <20040910015921.11cb17de.felix.klee@inka.de>

On 9 Sep 2004 08:57:46 -0700 --CELKO-- wrote:
> >> there still is the problem that the main table may contain entries
> for which there are no [rows in] subtables. <<
>
> In intermediate SQL-92, all table level constraints are TRUE for an
> empty table, so you need to have full SQL-92 and use a cross table
> constraint. That would be either a CREATE ASSERTION statement or a
> CHECK() that has a predicate that references the other table.

Thanks for pointing that out. However, to my knowledge PostgreSQL is not capable of the above. I guess there may be alternative solutions, though.

Felix Received on Thu Sep 09 2004 - 18:59:21 CDT