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  • Question
  • A subtype discriminator is which of the following?


  • Options
  • 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

  • Correct Answer
  • An attribute of the supertype whose values determine the subtype 


  • ER Model and Business Rules problems


    Search Results


    • 1. A supertype/subtype hierarchy is which of the following?

    • Options
    • 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.
    • Discuss
    • 2. Which one of the following symbols is not used in an ERD?

    • Options
    • A. Rectangle
    • B. Oval
    • C. Diamond
    • D. Circle
    • Discuss
    • 3. An oval represents which of the following in an EER?

    • Options
    • A. Attribute
    • B. Entity
    • C. Optional One
    • D. Relationship
    • Discuss
    • 4. An action assertion must include which of the following?

    • Options
    • A. Anchor object
    • B. Action
    • C. Corresponding object
    • D. All of the above.
    • Discuss
    • 5. 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?

    • Options
    • A. Disjoint with total specialization
    • B. Disjoint with partial specialization
    • C. Overlap with total specialization
    • D. Overlap with partial specialization
    • Discuss
    • 6. Use of a supertype/subtype relationship is necessary when which of the following exists?

    • Options
    • 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.
    • Discuss
    • 7. Inheritance is which of the following?

    • Options
    • A. When a supertype entity inherits values of the subtype attribute
    • B. When a subtype entity inherits values of the supertype attribute
    • C. When a supertype entity inherits values of another supertype attribute
    • D. When a subtype entity inherits values of another subtype attribute
    • Discuss
    • 8. When an entity instance must be a member of only one subtype, it is which of the following?

    • Options
    • A. Disjoint with total specialization
    • B. Disjoint with partial specialization
    • C. Overlap with total specialization
    • D. Overlap with partial specialization
    • Discuss
    • 9. A rectangle represents which of the following in an EER?

    • Options
    • A. Attribute
    • B. Entity
    • C. Optional One
    • D. Relationship
    • Discuss
    • 10. Specialization is which of the following processes?

    • Options
    • A. Defining one or more subtypes of the supertype and forming supertype/subtype relationships.
    • B. Defining one or more supertypes of the subtype and forming supertype/subtype relationships.
    • C. Defining one or more subtypes of the supertype and not forming supertype/subtype relationships.
    • D. Defining one or more supertypes of the subtype and not forming supertype/subtype relationships.
    • Discuss


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