Re: Ternary Relationship cardinality

miklesw_at_gmail.com wrote:
> I am working on an assignment which has 2 ternary relationship. I'm
> can't figure out their cardinality.
>
> Maybe I am going through one of those mental blocks...
>
> Can someone give me some cardinality examples for N-ary relationships?
> all the pics i found on google images don't include this..

Cardinality = number of { rows, records, tuples } in a relation.

Count the number of 'rows' in the table - that's the cardinality.

Degree = number of { fields, columns, attributes }.

Ternary relations have degree 3 (or 'are of degree 3').

> My other option is to convert the 3-ary relationship into a weak
> entity.. but I'll definitely loose marks on that

You may also lose marks for misspelling 'lose' (and not using plurals, and using "I'm can't" for "I can't", etc).

 > [...]

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