In order to define the relationship between two entity sets, which of the following operations can be used?
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Correct answer: C. Cartesian product
Explanation
In the Entity-Relationship (ER) model, a relationship set is formally defined as a mathematical relation among entities, i.e. a subset of the Cartesian product of the participating entity sets (e1 × e2 × ... × en). Each tuple in this subset represents one relationship instance linking the corresponding entities. Concatenation, adding and union do not model how entities from two different entity sets are associated, so Cartesian product is the correct operation.More Database Management Systems questions
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