DBMS Multiple choice Questions and Answers-Data Models

81.	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: (a).Encapsulation

82.	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: (c).Total specialization rule

83.	Which of the following is an unordered collection of elements that may contain duplicates?
a.	Set
b.	Bag
c.	List
d.	Dictionary

Answer: (b).Bag

84.	Which of the following is an ordered collection of elements of the same type?
a.	Set
b.	Bag
c.	List
d.	Dictionary

Answer: (c).List

85.	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: (d).All of the above.

86.	Using ODL, you can define which of the following?
a.	Attribute
b.	Structure
c.	Operation
d.	All of the above.

Answer: (d).All of the above.

87.	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: (d).Both directions.

88.	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: (a).Similar to SQL and uses a select-from-where structure

89.	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: (d).All of the above.

90.	Identify the class name for the following code: ABC123 course();
a.	ABC123
b.	course
c.	course()
d.	All of the above.

Answer: (a).ABC123