Re: Designer/2000 ERD Cardinalities

[Quoted] rgordon_at_acpub.duke.edu (Robert Gordon) wrote:

The notation is unique to Oracle. I happen to like it, as it reduces the number of symbols hanging on the line, and also focuses on "optionality" of the relationship instead of "minimum cardinality".

Focusing on the line half closest to the entity also lets you know the optionality of the resulting FK columns...

The notation uses "MUST BE" and "MAY BE" in place of "zero..." when reading the relationships.

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>> Jeffrey Jacobs & Associates
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>This is the opposite of what I initially thought. It seemed intuitive
>that the half of the line closer to the crows foot would indicate
>optionality at that end (like IE). BTW, is Oracle using a methodology
>I just haven't learned or did they make this up to confuse people?
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>Thanks Jeff
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>> Oracle Designer/2000 Consulting & Training
>> 951-2 Old Country Road, Suite 119, Belmont, CA 94002
>> Voice: 415-571-7092, FAX: 800-665-1379 CompuServe: 76702,456
>> Internet: jmjacobs_at_ix.netcom.com
>>
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>- Robert Gordon
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-JJ

 Jeffrey Jacobs & Associates
 Oracle Designer/2000 Consulting & Training  951-2 Old Country Road, Suite 119, Belmont, CA 94002  Voice: 415-571-7092, FAX: 800-665-1379 CompuServe: 76702,456  Internet: jmjacobs_at_ix.netcom.com     Received on Fri Jan 03 1997 - 00:00:00 CET