Re: a union is always a join!
Date: Tue, 10 Mar 2009 02:47:14 -0700 (PDT)
Message-ID: <40ee4562-49e3-4254-9b66-e6412a4e4832_at_w35g2000yqm.googlegroups.com>
On Mar 9, 4:33 pm, Tegiri Nenashi <TegiriNena..._at_gmail.com> wrote:
> Moreover, the state is probably a
> calculated value, function of time and perhaps some other conditions.
If you are interested you can find the definition of a state of an
entity or relationship in my paper about new data model. I posted it a
few days ago on this user group, under topic:
A new db model/design
or you can go directly to my web site:
www.dbdesign11.com
It is definition 4.2.4.1 in the paper Database Design and Data Model
Founded on Concept and Knowledge construct. You can find there
examples about the states. I applied the idea about the states in very
complex DB projects and m-n relationships.
Vladimir Odrljin Received on Tue Mar 10 2009 - 10:47:14 CET