When changing the minimum cardinality on the parent side of the relationship from zero to one,the foreign key ________.
A)must be changed from NULL to NOT NULL
B)must be changed from NOT NULL to NULL
C)must be changed to a composite key
D)must be changed to a surrogate key
E)does not change

Question

Quizplus · Accepted Answer

When changing the minimum cardinality on the parent side of the relationship from zero to one, it means that every child entity must have a parent. Therefore, the foreign key cannot be NULL, and must be changed to NOT NULL.

When Changing the Minimum Cardinality on the Parent Side of the Relationship