Database - Object-Oriented Data Modeling MCQs Part

1. The fact that the same operation may apply to two or more classes is called what?

A.
Inheritance
B.
Polymorphism
C.
Encapsulation
D.
Multiple classification

 Answer Option B

2. The object-oriented development life cycle is which of the following?

A.
Analysis, design, and implementation steps in the given order and using multiple iterations.
B.
Analysis, design, and implementation steps in the given order and going through the steps no more than one time.
C.
Analysis, design, and implementation steps in any order and using multiple iterations.
D.
Analysis, design, and implementation steps in any order and going through the steps no more than one time.

 Answer Option A

3. Multiplicity is the same as what concept for an ERD?

A.
Relationship
B.
Attribute
C.
Entity
D.
Cardinality

 Answer Option D

4. Composition is a stronger form of which of the following?

A.
Aggregation
B.
Encapsulation
C.
Inheritance
D.
All of the above.

 Answer Option A

5. An abstract class is which of the following?

A.
A class that has direct instances, but whose descendants may have direct instances.
B.
A class that has no direct instances, but whose descendants may have direct instances.
C.
A class that has direct instances, but whose descendants may not have direct instances.
D.
A class that has no direct instances, but whose descendants may not have direct instances

 Answer Option B

6. The term Complete for a UML has the same meaning as which of the following for an EER diagram?

A. Overlapping rule
B. Disjoint rule
C. Total specialization rule
D. Partial specialization rule

 Answer Option C

7. A UML diagram includes which of the following?

A. Class name
B. List of attributes
C. List of operations
D. All of the above.

 Answer Option D

8. An object can have which of the following multiplicities?

A. Zero
B. One
C. More than one
D. All of the above.

 Answer Option D

9. Which of the following statement is true concerning objects and/or classes?

A. An object is an instance of a class.
B. A class is an instance of an object.
C. An object includes encapsulates only data.
D. A class includes encapsulates only data.

 Answer Option A

10. Which of the following applies to a class rather than an object?

A. Query
B. Update
C. Scope
D. Constructor

 Answer Option C

11. The benefits of object-oriented modeling are which of the following?

A. The ability to tackle more challenging problems
B. Reusability of analysis, design, and programming results
C. Improved communication between users, analysts, etc.
D. All of the above.

 Answer Option D

12. The term Incomplete for a UML has the same meaning as which of the following for an EER diagram?

A. Overlapping rule
B. Disjoint rule
C. Total specialization rule
D. Partial specialization rule

 Answer Option D

13. A constructor operation does which of the following?

A. Creates a new instance of a class
B. Updates an existing instance of a class
C. Deletes and existing instance of a class
D. All of the above.

 Answer Option A

14. Which of the following is a technique for hiding the internal implementation details of an object?

A. Encapsulation
B. Polymorphism
C. Inheritance
D. All of the above.

 Answer Option A

15. Aggregation is which of the following?

A. Expresses a part-of relationship and is a stronger form of an association relationship.
B. Expresses a part-of relationship and is a weaker form of an association relationship.
C. Expresses an is-a relationship and is a stronger form of an association relationship.
D. Expresses an is-a relationship and is a weaker form of an association relationship.

 Answer Option A

6. The term Complete for a UML has the same meaning as which of the following for an EER diagram?

A. Overlapping rule
B. Disjoint rule
C. Total specialization rule
D. Partial specialization rule

 Answer Option C

7. A UML diagram includes which of the following?

A. Class name
B. List of attributes
C. List of operations
D. All of the above.

 Answer Option D

8. An object can have which of the following multiplicities?

A. Zero
B. One
C. More than one
D. All of the above.

 Answer Option D

9. Which of the following statement is true concerning objects and/or classes?

A. An object is an instance of a class.
B. A class is an instance of an object.
C. An object includes encapsulates only data.
D. A class includes encapsulates only data.

 Answer Option A

10. Which of the following applies to a class rather than an object?

A. Query
B. Update
C. Scope
D. Constructor

 Answer Option C

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