Use of a supertype/subtype relationship is necessary when which of the following exists? An instance of a subtype participates in a relationship that is unique to that subtype. An instance of a subtype participates in a relationship that is the same as the other subtypes. Attributes apply to all of the instances of an entity type. No attributes apply to any of the instances of an entity type. TRUE ANSWER : ? YOUR ANSWER : ?
A subtype discriminator of the supertype is an attribute whose values determine the target subtype(s). True False TRUE ANSWER : ? YOUR ANSWER : ?
An action assertion must include which of the following? Corresponding object Action All of these Anchor object TRUE ANSWER : ? YOUR ANSWER : ?
Which one of the following symbols is not used in an ERD? Diamond Rectangle Circle Oval TRUE ANSWER : ? YOUR ANSWER : ?
A supertype/subtype hierarchy has which of the following features? Subtypes at the higher lever in the hierarchy inherit attributes only from their immediate subtype. Attributes are assigned at the lowest logical level. Attributes are assigned at the highest logical level. Subtypes at the lower lever in the hierarchy inherit attributes only from their immediate supertype. TRUE ANSWER : ? YOUR ANSWER : ?
It is appropriate to use a supertype/subtype relationship when there are attributes that apply to some of the instances of an entity type. True False TRUE ANSWER : ? YOUR ANSWER : ?
An ERD that has had the entities clustered will display more entities. True False TRUE ANSWER : ? YOUR ANSWER : ?
A supertype is an entity type that shares common attributes or relationships distinct from other subgroupings. False True TRUE ANSWER : ? YOUR ANSWER : ?
When an entity instance may be a member of multiple subtypes or it does not have to be a member of a subtype, it is which of the following? Disjoint with total specialization Disjoint with partial specialization Overlap with total specialization Overlap with partial specialization TRUE ANSWER : ? YOUR ANSWER : ?
There is cardinality on an EER between the supertype and subtype. True False TRUE ANSWER : ? YOUR ANSWER : ?