Re: many to many relationship

From: Paul Vernon <paul.vernon_at_ukk.ibmm.comm>
Date: Fri, 7 Mar 2003 15:20:34 -0000
Message-ID: <b4adf6$emg$1@sp15at20.hursley.ibm.com>

"Alan" <alan_at_erols.com> wrote in message news:b4a9p3$1tdad9$1_at_ID-114862.news.dfncis.de...
> Don't confuse the conceptual model with the physical model

As if I would

> An ERD models the business.

My point is that classic Entity Relationship Diagrams are *not* a great way to model a business if they encourage you to hide entities such as 'enrolment from your conceptual model.

In fact as many common constraints (aka business rules) are not representable graphically in Entity Relationship Diagrams, I don't find they make good conceptual models at all. ORM is generally much better.

Regards
Paul Vernon
Business Intelligence, IBM Global Services Received on Fri Mar 07 2003 - 09:20:34 CST