Domain constraints, functional dependency and referential integrity

domain-constraints-functional-dependency-and-referential-integrity

Domain constraints, functional dependency and referential integrity are special forms of _________

A. Foreign key

B. Primary key

C. Assertion

D. Referential constraint

I got this question in exam.

The origin of the question is Integrity Constraints in portion SQL : Queries, Constraints and Triggers of Database Management

The correct answer is C. Assertion

Best explanation: An assertion is a predicate expressing a condition we wish the database to always satisfy.