Entity Relationship Model: Ternary Relationships

Posted by Ethan on Stack Overflow See other posts from Stack Overflow or by Ethan
Published on 2010-04-08T23:47:01Z Indexed on 2010/04/08 23:53 UTC
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ternary

Hi, I am trying to understand why this statement in the book is wrong: "given a C entity, there is at most one related A entity and at most one related B entity". Is it that it doesn't apply to a specific kind of relationship?? So, if I have an example of a student who is in attendance to a course with a type of subject. The entities are student, attendance, course and subject. Student makes attendance in a room. Also, a student can make attendance for a subject. Does this example apply to the statement?

Thanks for your time.

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