EER

Question 1

Multi valued Attributes favored over

Answer 1

Compound Attributes

Question 2

Union

Answer 2

Employee
      |
      |
      |
     U
      |
Technician

The technician inherits all of the employee attributes in addition to its own

Question 3

Disjoint

Answer 3

Employee
      |                      
      d---------U---- Secretary 
      |
     U
      |
Technician

An employee can either be a secretary or technician, but not both. (XOR)

Question 4

Sub classes and Super classes

Answer 4

Employee
      |                      
      d---------U---- Secretary 
      |
     U
      |
Technician

The technician and secretary are sub classes of employee. The employee is a super class of secretary and technician.

Question 5

Specialization

Answer 5

Process of defining a set of sub classes of an entity type

Question 6

Generalization

Answer 6

Start with subclasses and define superclasses

Question 7

Overlap (o)

Answer 7

Specifies that sublcasses are not constrained to be disjoint

Question 8

Completeness Constraint

Answer 8

Says that every entity must be one of the subclasses