Composite primary keys are particularly useful as identifiers of composite entities, where each primary key combination is allowed only once in the _____ relationship.
A) 0:1
B) 1:1
C) 1:M
D) M:N

Question

Quizplus · Accepted Answer

Composite primary keys are especially useful in many-to-many (M:N) relationships because they allow for the unique identification of each relationship instance between entities. In a many-to-many relationship, a composite entity (also known as a join table or associative entity) is often used to connect the two entities, and the composite primary key ensures that each combination of connections between the entities occurs only once.

Composite Primary Keys Are Particularly Useful as Identifiers of Composite