Related Questions

Overlapping and disjoint subtypes have different approaches on how the subtype discriminator is applied.
A True
B False
A subtype discriminator is which of the following?
A An attribute of the supertype whose values determine the subtype
B An attribute of the subtype whose values determine the supertype
C An attribute of the supertype whose values determine the supertype
D An attribute of the subtype whose values determine the subtype
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?
A Disjoint with total specialization
B Disjoint with partial specialization
C Overlap with total specialization
D Overlap with partial specialization
A supertype/subtype hierarchy is which of the following?
A Each subtype has only one attribute
B Each supertype has only one attribute
C Each subtype has only one supertype
D Each supertype has only one subtype
Use of a supertype/subtype relationship is necessary when which of the following exists?
A An instance of a subtype participates in a relationship that is unique to that subtype
B An instance of a subtype participates in a relationship that is the same as the other subtypes
C Attributes apply to all of the instances of an entity type
D No attributes apply to any of the instances of an entity type
A supertype/subtype hierarchy has which of the following features?
A Subtypes at the lower lever in the hierarchy inherit attributes only from their immediate supertype.
B Subtypes at the higher lever in the hierarchy inherit attributes only from their immediate subtype.
C Attributes are assigned at the highest logical level.
D Attributes are assigned at the lowest logical level.
When mapping a supertype/subtype relationship which of the following is true?
A The supertype primary key is assigned to each subtype.
B The subtype primary key is assigned to each supertype.
C There is no link between the supertype\/subtype entities.
D There is no primary key\/foreign key relationship between a supertype\/subtype.
It is appropriate to use a supertype/subtype relationship when there are attributes that apply to some of the instances of an entity type.
A True
B False
Which type of entity has its relationship to another entity determined by an attribute in that other entity called a discriminator?
A Supertype entity
B Subtype entity
C Archetype entity
D Instance entity
A derived attribute is an attribute whose values can be calculated from a related relationship.
A True
B False

Next steps