Re: Does Codd's view of a relational database differ from that ofDate&Darwin?[M.Gittens]
From: Marshall Spight <marshall.spight_at_gmail.com>
Date: 1 Jul 2005 11:01:43 -0700
Message-ID: <1120240903.816273.78580_at_f14g2000cwb.googlegroups.com>
Date: 1 Jul 2005 11:01:43 -0700
Message-ID: <1120240903.816273.78580_at_f14g2000cwb.googlegroups.com>
Alexandr Savinov wrote:
>
> Yes, there should be multiple layers where lower layers implement the
> mechanism of representation and acces for higher levels. But in the RM
> there is no such a separation we have to keep absolutely different
> things (object representation/access vs. their semantics) in one box.
RM has the best such separation of any model I've encountered. In fact, it's so good that it's tricked you into thinking it doesn't exist.
This is one of Codd's original 12 rules. Rule 8 in fact.
Marshall Received on Fri Jul 01 2005 - 20:01:43 CEST