N-ary Relationships, What a Mess

نویسنده

  • Rafael Camps Paré
چکیده

The transformation from n-ary relationships to a relational database schema has never been really fully analyzed. This paper presents one of the several ternary cases ignored by the ER-to-RM literature. The case shows that the following common belief is wrong: Given a set of FDs over a table resulting in a non-3NF situation, it is always possible to obtain a fully equivalent set of 3NF tables, without adding other restrictions than candidate keys and elementary inclusion dependencies.

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تاریخ انتشار 2002