Database Management System MCQs with Answers
Practice important Database Management System MCQs with answers and explanations.
Multiple Choice Questions
Q131: Fill in the blank: A __________ key is a candidate key that is not chosen as the primary key.
- A: secondary
- B: key
- C: foreign
- D: alternate
View Answer
D
Q132: Fill in the blank: The key that uniquely identifies a single entity instance among many instances is called a __________ key.
- A: super
- B: candidate
- C: primary
- D: foreign
View Answer
C
Q133: Which of the following is NOT a type of key mentioned in the content?
- A: Primary Key
- B: Foreign Key
- C: Index Key
- D: Secondary Key
View Answer
C
Q134: An attribute that is either required or optional means it:
- A: Must always have a value
- B: Might or might not have a value
- C: Can be empty but must be defined
- D: Is always defined as mandatory
View Answer
B
Q135: Which key can consist of one or more attributes but is not necessarily minimal?
- A: Primary Key
- B: Alternate Key
- C: Candidate Key
- D: Super Key
View Answer
D
Q136: Fill in the blank: If a composite super key has a subset that can also uniquely identify entity instances, it is called a __________ key.
- A: candidate
- B: primary
- C: secondary
- D: foreign
View Answer
A
Q137: Which attribute in the STUDENT entity type is an example of a super key?
- A: regNo
- B: name
- C: phoneNo
- D: address
View Answer
A
Q138: What is a relationship in an E-R data model?
- A: A connection between entities
- B: A type of attribute
- C: A unique identifier
- D: A data type
View Answer
A
Q139: What does the degree of a relationship refer to?
- A: The number of entities involved
- B: The number of attributes per entity
- C: The uniqueness of entity instances
- D: The cardinality of the relationship
View Answer
A
Q140: Which of the following is an example of a binary relationship?
- A: Student-Class
- B: Student-Student
- C: Student-Student-Faculty
- D: Student-Class-Faculty
View Answer
A