Final answer:
The statement is true; the completeness constraint determines if a supertype entity occurrence must be a member of at least one subtype, which reflects the business rules of the database structure.
Step-by-step explanation:
The completeness constraint in data modeling specifies whether each supertype entity occurrence must also be a member of at least one subtype. Therefore, the statement is true. In terms of data modeling, when we discuss supertypes and subtypes, we refer to a generalization/specialization hierarchy where a supertype is a generic entity that has a relationship with one or more specialized, or subtype, entities.
When a completeness constraint is total, then every instance of the supertype must be a member of at least one subtype. However, when the constraint is partial, it is not necessary for every instance of the supertype to belong to a subtype. The designer must specify these constraints to ensure the integrity of the database structure and to correctl