Practice important DBMS Normalization MCQ questions with answers and explanations. These questions cover key concepts like 1NF, 2NF, 3NF, BCNF, and functional dependencies. Useful for IBPS IT Officer, GATE, and other competitive exams.
Difficulty: Easy to Medium
Total Questions: 12
Important DBMS Normalization MCQ Questions
Q1. What is the main purpose of normalization in DBMS?
A. Increase data redundancy
B. Reduce data redundancy and improve integrity
C. Speed up data retrieval only
D. Store data in multiple files
View Answer & Explanation
Answer: B
Explanation: Normalization organizes data to minimize redundancy and avoid anomalies, ensuring data consistency and integrity.
Q2. First Normal Form (1NF) requires that:
A. All attributes must be atomic
B. All attributes must be multi-valued
C. All attributes must be derived
D. All attributes must be keys
View Answer & Explanation
Answer: A
Explanation: 1NF ensures that each attribute contains only atomic (indivisible) values, eliminating repeating groups.
Q3. Which normal form removes partial dependency?
A. 1NF
B. 2NF
C. 3NF
D. BCNF
View Answer & Explanation
Answer: B
Explanation: 2NF removes partial dependencies where a non-prime attribute depends only on part of a composite key.
Q4. A relation is in 2NF if it is in 1NF and:
A. Has no transitive dependency
B. Has no partial dependency
C. Has no functional dependency
D. Has only one attribute View Answer & Explanation
View Answer & Explanation
Answer: B
Explanation: 2NF ensures that all non-prime attributes are fully dependent on the entire primary key.
Q5. Which normal form removes transitive dependency?
A. 1NF
B. 2NF
C. 3NF
D. 4NF
View Answer & Explanation
Answer: C
Explanation: 3NF eliminates transitive dependencies where non-key attributes depend on other non-key attributes.
Q6. A relation is in 3NF if it is in 2NF and:
A. No transitive dependency exists
B. No functional dependency exists
C. No multi-valued dependency exists
D. All attributes are keys
View Answer & Explanation
Answer: A
Explanation: 3NF requires removal of transitive dependencies to ensure proper normalization.
Q7. Boyce-Codd Normal Form (BCNF) is a stricter version of:
A. 1NF
B. 2NF
C. 3NF
D. 4NF
View Answer & Explanation
Answer: C
Explanation: BCNF is a stricter form of 3NF where every determinant must be a super key.
Q8. Which of the following is TRUE regarding BCNF?
A. Every 3NF relation is in BCNF
B. BCNF is less strict than 3NF
C. Every BCNF relation is in 3NF
D. BCNF allows partial dependency
View Answer & Explanation
Answer: C
Explanation: BCNF is stricter than 3NF, so every BCNF relation automatically satisfies 3NF conditions.
Q9. If a relation has composite primary key (A, B) and A → C, then this is an example of:
A. Transitive dependency
B. Partial dependency
C. Functional dependency
D. Multi-valued dependency
View Answer & Explanation
Answer: B
Explanation: C depends only on A (part of the key), which is a partial dependency violating 2NF.
Q10. Which normal form deals with multi-valued dependencies?
A. 2NF
B. 3NF
C. BCNF
D. 4NF
View Answer & Explanation
Answer: D
Explanation: 4NF removes multi-valued dependencies to further normalize relations.
Q11. A relation is in BCNF if:
A. Every attribute is prime
B. Every determinant is a super key
C. No dependency exists
D. All attributes are atomic
View Answer & Explanation
Answer: B
Explanation: In BCNF, every functional dependency must have a super key on the left-hand side.
Q12. Why is 3NF often preferred over BCNF in practice?
A. BCNF is simpler
B. 3NF preserves functional dependencies
C. BCNF improves performance always
D. 3NF removes all redundancy
View Answer & Explanation
Answer: B
Explanation: 3NF is often preferred because it ensures dependency preservation while maintaining reasonable normalization.
Conclusion
These DBMS Normalization MCQ questions help strengthen concepts like 1NF, 2NF, 3NF, BCNF, and functional dependencies. Regular practice improves conceptual clarity and exam performance.
For detailed theory, refer to DBMS Normalization concepts .