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Cyclical Relation.

From: kk <kk_at_tuputamadre.com>
Date: Tue, 24 Apr 2001 11:56:57 +0200
Message-ID: <3ae54dd3$1_at_news> 






Hi Friends, i've a little problem with a database design, and i've found
several solutions....but i'd like to heard from you...



The example is really easy...



User            Message
--------        --------
IdUser         IdMessage
Name          Date
                   Title
                   Body





Each User has some data that is only for that user like readed, active....



What E/R Model should cover this and without finishing in a cyclical
relation between User and Message.. If....



Send Action


1 user can send 1 or many messages


1 message can be sent by only 1 user



Receive Action


1 user can receive 1 or many messages


1 message is owned by 1 user.




Regards and Thanks in Advance.
Received on Tue Apr 24 2001 - 11:56:57 CEST












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