DBMS Objective Questions and Answers

This DBMS quiz contains carefully curated objective questions with correct answers and clear explanations. It is designed for computer science students, backend developers, and interview preparation, focusing on database design, SQL internals, transactions, indexing, and performance tuning.

Practice DBMS MCQs with Detailed Explanations

Answer at least 12 questions to submit and verify answers.

1 Which normal form eliminates transitive dependency? Easy

2 Which SQL clause is evaluated first in query execution? Medium

3 Which index structure is best suited for range queries? Medium

4 What anomaly is prevented by 2NF? Medium

5 Which isolation level allows dirty reads? Medium

6 Which schedule is conflict serializable? High

7 What is the main purpose of a checkpoint in recovery? Medium

8 Which join algorithm is most efficient when one relation fits entirely in memory? Medium

9 Which condition causes a deadlock? Medium

10 Which operation cannot be performed on a view without INSTEAD OF trigger? Medium

11 Which locking protocol guarantees conflict serializability? High

12 Which normal form is stricter than 3NF? Medium

13 What is the output of COUNT(column) when all values are NULL? Medium

14 Which index consumes the least storage? Medium

15 What does WAL ensure? High