Re: Peter Chen and Charles Bachman
From: Laconic2 <laconic2_at_comcast.net>
Date: Thu, 6 May 2004 08:23:27 -0400
Message-ID: <_a2dncSTBridswfdRVn-ig_at_comcast.com>
Date: Thu, 6 May 2004 08:23:27 -0400
Message-ID: <_a2dncSTBridswfdRVn-ig_at_comcast.com>
Nonsense. I can see you've never worked with an ER model.
Every ER model I've seen models relationships as either mandatory or optional, and as many-many many-one or one-one. Those are constraints. Most ER models classify attributes as single valued or multivalued. Some go further to list some attributes as optional.
You would do well to learn more about a tool before dismissing it. Received on Thu May 06 2004 - 14:23:27 CEST