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Re: relationship notation explanation
Posted by: Mike Lischke
Date: March 14, 2013 02:33AM

Dimitris,

these numbers represent the cardinality of the relationship. A 0 means zero or more, a 1 means 1 or more and ∞ means infinite. It's a fairly common symbol for infinity.

So as a result you can have have 1:1, 1:n, m:n etc relationships. The zero is a special case of 1:x, describing a non-mandatory relationship.

Mike

Mike Lischke, MySQL Developer Tools
Oracle Corporation

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relationship notation explanation
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Dimitris Papageorgiou
March 13, 2013 09:32AM
Re: relationship notation explanation
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Mike Lischke
March 14, 2013 02:33AM


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