LEESON 4 QUIZ
1.Which of the following notations indicates a specialization/generalization with the disjoint constraint?
A. Blank triangle
2. Which of the following classes defines attribures and operations but does not have objects corresponding to these classes?
A. Abstract
3.Which of the following is an abstraction concept for building composite objects from their component objects?
A. Aggregation
4. Which is the process of classifying a class of objects into more specialized subclasses?
A. Specialization
LESSON 5 QUIZ
1. which of the following constraints is violated by the delete operation?
A. Referential integrity
2. Which of the following constraints is expressed directly in the schemas of the data model?
A) Explicit
3. which of the following constraints states that no prinary key value can be NUUL?
A) Entity integrity
LESSON 6 QUIZ
1.which of the following commands specifies a new relation by fiving it a name and specifying its attributes and initial constraints?
A). CERATE TABLE
2. Which of the following clauses lists the attributes to be retrieved?
A). SELECT
3. which of the following clauses identifies the conditions for selecting the tuples from the relations?
A) Where
LAB
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