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Re: About Entity Relation Diagram

From: birdadderley <david.engfer_at_gmail.com>
Date: 19 Dec 2004 23:10:11 -0800
Message-ID: <1103526611.766447.256190@z14g2000cwz.googlegroups.com>


Well if you wanted to read some theory here on people argue about different database types, well there you have it.

Whomever said you shouldn't even be thinking about your schema yet is exactly correct. In the ER diagram you create and brainstorm over, you will eventually convert to tables. If you are thinking about tables in order to create the ER diagram, well theres no point in drawing one up. If you run into problems, bo back to your ER diagram and reorganize; there are probably some relationships that you can clean up/make easier.

As far as your table situation mentioned; the PerfectPartner table sounds like a many to many table between members. Therefore at a minimum PerfectPartner should have unique pairs of members.PK -- members.PK sets. (making sure that you apply constraints so that 4 -- 2 is different than 2 -- 4) Received on Mon Dec 20 2004 - 01:10:11 CST

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