Which of the following is a specialization hierarchy overlapping constraint scenario in case of partial completeness?
A) Subtype sets are unique.
B) Supertype has optional subtypes.
C) Subtype discriminators cannot be null.
D) Subtype does not have a supertype.

Question

Quizplus · Accepted Answer

In a specialization hierarchy with partial completeness, an overlapping constraint occurs when a supertype has optional subtypes, meaning that not all instances of the supertype need to have a matching subtype. This can lead to ambiguity in query results and difficulties in maintaining data integrity. Therefore, option B is the correct choice. Options A, C, and D do not describe a specialization hierarchy with partial completeness and do not relate to overlapping constraint scenarios.

Which of the Following Is a Specialization Hierarchy Overlapping Constraint