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Referential Integrity in the E-R Model

  1. These constraints arise frequently. Every relation arising from a relationship set has referential integrity constraints.

    Figure 6.1: An n-ary relationship set

  2. Relation schemes for weak entity sets must include the primary key of the strong entity set on which they are existence dependent. This is a foreign key, which leads to another referential integrity constraint.

Osmar Zaiane
Tue Jun 9 15:12:55 PDT 1998