Database - Object-Oriented Database MCQs Part

1. ODL supports which of the following types of association relationships?

A.
Unary
B.
Unary and Binary
C.
Unary and Binary and Ternary
D.
Unary and Binary and Ternary and higher

 Answer Option B

2. An extent is which of the following?

A.
A keyword that indicates that the subclass inherits from a superclass
B.
A keyword that indicates that the superclass inherits from a subclass
C.
The set of all instances of a class within a database
D.
Only one instance of a class within a database

 Answer Option C

3. Identify the class name for the following code: ABC123 course();

A.
ABC123
B.
course
C.
course()
D.
All of the above.

 Answer Option A

4. Using ODL, you can define which of the following?

A.
Attribute
B.
Structure
C.
Operation
D.
All of the above.

 Answer Option D

5. The keyword "inverse" is used in which of the following?

A.
Class
B.
Attribute
C.
Relationship
D.
All of the above.

 Answer Option C

6. The object definition language (ODL) is which of the following?

A. Used to develop logical schemas
B. A data definition language for OODB
C. A method to implement a logical schema
D. All of the above.

 Answer Option D

7. An atomic literal is which of the following?

A. Strings
B. Boolean
C. Long
D. All of the above.

 Answer Option D

8. Which of the following is true concerning an ODBMS?

A. They have the ability to store complex data types on the Web.
B. They are overtaking RDBMS for all applications.
C. They are most useful for traditional, two-dimensional database table applications.
D. All of the above.

 Answer Option A

9. The reserved word enum is used for which of the following?

A. To define a range for an attribute.
B. To define a range for a class.
C. To define a range for a relationship.
D. All of the above.

 Answer Option A

10. Which of the following is an unordered collection of elements that may contain duplicates?

A. Set
B. Bag
C. List
D. Dictionary

 Answer Option B

11. Which of the following is true concerning the following statement: class Manager extends Employee

A. Manager is a concrete class and a superclass.
B. Manager is a concrete class and a subclass.
C. Manager is an abstract class and a superclass.
D. Manager is an abstract class and a subclass.

 Answer Option B

12. Which of the following is an ordered collection of elements of the same type?

A. Set
B. Bag
C. List
D. Dictionary

 Answer Option C

13. A relationship should be specified how in the ODL?

A. One direction starting with the first class
B. One direction starting with the second class
C. Neither direction.
D. Both directions.

 Answer Option D

14. Using OQL, you may do which of the following?

A. Return an entire collection of elements including duplicates.
B. Return a collection of elements without duplicates.
C. Return a specific subset of elements using a given criteria.
D. All of the above.

 Answer Option D

15. The Object Query Language is which of the following"?

A. Similar to SQL and uses a select-from-where structure
B. Similar to SQL and uses a select-where structure
C. Similar to SQL and uses a from-where structure
D. Not similar to SQL

 Answer Option A

6. The object definition language (ODL) is which of the following?

A. Used to develop logical schemas
B. A data definition language for OODB
C. A method to implement a logical schema
D. All of the above.

 Answer Option D

7. An atomic literal is which of the following?

A. Strings
B. Boolean
C. Long
D. All of the above.

 Answer Option D

8. Which of the following is true concerning an ODBMS?

A. They have the ability to store complex data types on the Web.
B. They are overtaking RDBMS for all applications.
C. They are most useful for traditional, two-dimensional database table applications.
D. All of the above.

 Answer Option A

9. The reserved word enum is used for which of the following?

A. To define a range for an attribute.
B. To define a range for a class.
C. To define a range for a relationship.
D. All of the above.

 Answer Option A

10. Which of the following is an unordered collection of elements that may contain duplicates?

A. Set
B. Bag
C. List
D. Dictionary

 Answer Option B

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