Database Management System MCQs with Answers
Practice important Database Management System MCQs with answers and explanations.
Multiple Choice Questions
Q141: What type of relationship involves three entities?
- A: Unary relationship
- B: Binary relationship
- C: Ternary relationship
- D: N-ary relationship
View Answer
C
Q142: Which symbol indicates total participation in an ER diagram?
- A: Single line
- B: Double line
- C: Dotted line
- D: Dashed line
View Answer
B
Q143: A relationship where entities link to themselves is called a ________ relationship.
- A: Binary
- B: Unary
- C: Ternary
- D: N-ary
View Answer
B
Q144: In an E-R diagram, what does a diamond represent?
- A: An attribute
- B: A relationship
- C: A key
- D: A role
View Answer
B
Q145: What is an example of a unary relationship?
- A: Student-Class
- B: Employee-Project
- C: Student-Roommate
- D: Student-Faculty
View Answer
C
Q146: In a one-to-many mapping, how are entities in X and Y related?
- A: Each entity in X maps to many entities in Y, and each entity in Y maps to one entity in X
- B: Each entity in X maps to one entity in Y, and each entity in Y maps to many entities in X
- C: Each entity in X maps to many entities in Y, and each entity in Y maps to many entities in X
- D: Each entity in X maps to one entity in Y, and each entity in Y maps to one entity in X
View Answer
A
Q147: A ________ key can have multiple attributes.
- A: Primary
- B: Secondary
- C: Foreign
- D: Candidate
View Answer
C
Q148: Which of the following relationships is characterized by entities interacting with themselves?
- A: Binary
- B: Unary
- C: Ternary
- D: N-ary
View Answer
B
Q149: In a many-to-many relationship, how many entities from X are associated with entities from Y?
- A: Each entity from X is associated with many entities in Y, and vice versa
- B: Each entity from X is associated with one entity in Y, and vice versa
- C: Each entity from X is associated with many entities in Y, and each entity in Y is associated with one entity in X
- D: Each entity from X is associated with one entity in Y, and each entity in Y is associated with many entities in X
View Answer
A
Q150: The cardinality of a relationship describes the ________.
- A: Number of entities in a relationship
- B: Number of attributes in a relationship
- C: The optionality of the relationship
- D: The roles involved in the relationship
View Answer
A