Re: Does Codd's view of a relational database differ from that ofDate& Darwin? [M.Gittens]
From: Alfredo Novoa <alfredo_novoa_at_hotmail.com>
Date: Tue, 07 Jun 2005 17:25:03 +0200
Message-ID: <62fba1h2791u7j3cmfn34h7oarhecebk2h_at_4ax.com>
Date: Tue, 07 Jun 2005 17:25:03 +0200
Message-ID: <62fba1h2791u7j3cmfn34h7oarhecebk2h_at_4ax.com>
On Tue, 07 Jun 2005 15:49:47 +0100, Paul <paul_at_test.com> wrote:
>I'd suggest that SQL's SUM *should* be iterated addition. And that all
>aggregates should return NULL if any of the attributes in the aggregated
>column are NULL. Surely if any of them are unknown, we must say that the
>sum or average is unknown also?
>
>What are the arguments for not doing this?
It does not eliminate nulls. Everything else is a botch-up.
Regards Received on Tue Jun 07 2005 - 17:25:03 CEST