N-ary relationship, Database Management System

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For every n-ary relationship type R where n>2, we make a new table S to represent R. We contain as foreign key attributes in s the primary keys of the relations that show the participating entity types. We also contain any easy attributes of the n-ary relationship type (or easy components of complete attributes) as attributes of S. The primary key of S is generally a combination of all the foreign keys that reference the relations showing the participating entity types. Figure  is a special case of n-ary relationship: a binary relation.


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