Entity Supertype

3 PAGES APA

1. What is an entity supertype, and why is it used?
2. What kinds of data would you store in an entity subtype?
3. What is a specialization hierarchy?
4. What is a subtype discriminator? Give an example of its use.
5. What is an overlapping subtype? Give an example.
6. What is a disjoint subtype? Give an example.
7. What is the difference between partial completeness and total completeness?

For Questions 8–10, refer to Figure Q5.8.

8. List all of the attributes of a movie.
9. According to the data model, is it required that every entity instance in the PRODUCT table be associated with an entity instance in the CD table? Why, or why not?
10. Is it possible for a book to appear in the BOOK table without appearing in the PRODUCT table? Why, or why not?