Top 50 Most Asked Database Interview Questions

Table of contents

Questions

1. What are the differences between SQL and NoSQL databases?

2. How do you design a database schema for a given application?

3. What is normalization, and why is it important?

4. What are indexes, and how do they improve database performance?

5. What is a primary key, and why is it important?

6. What are the different types of joins in SQL, and when would you use each?

7. What are transactions, and why are they important in databases?

8. How do you handle database migrations?

9. What are stored procedures, and what are their advantages and disadvantages?

10. How do you optimize SQL queries for performance?

11. What is database sharding, and when should it be used?

12. How do you ensure data consistency across distributed systems?

13. What are the common causes of database deadlocks, and how do you prevent them?

14. What are the differences between relational and non-relational databases?

15. What is the role of a database cache, and how does it work?

16. How do you manage database security and access control?

17. What are database replication and its benefits?

18. What is a database view, and how is it used?

19. How do you handle database backups and restore operations?

20. What tools do you use for database monitoring and profiling?

21. What is a foreign key, and how does it enforce referential integrity?

22. What is denormalization, and when would you use it?

23. How do you implement full-text search in a database?

24. What is the CAP theorem, and how does it relate to distributed databases?

25. What are the differences between a clustered and a non-clustered index?

26. What is the difference between DELETE and TRUNCATE commands in SQL?

27. How do you handle large-scale data imports and exports in a database?

28. What is a materialized view, and how does it differ from a regular view?

29. How do you ensure high availability in a database system?

30. What are the trade-offs between consistency and availability in distributed systems?

31. How do you design a database for multi-tenant applications?

32. What is the role of an ORM (Object-Relational Mapping) in database management?

33. How do you use transactions to ensure data integrity in a concurrent environment?

34. What is a connection pool, and why is it important for database performance?

35. What are the benefits and drawbacks of using stored procedures versus application logic?

36. How do you manage database versions and change control?

37. What is a database trigger, and how is it used?

38. How do you handle schema changes in a live production database?

39. What is eventual consistency, and how does it differ from strong consistency?

40. How do you implement role-based access control in a database?

41. What are the considerations for selecting a database technology for a new project?

42. How do you manage data archiving and purging in a database?

43. What are the differences between horizontal and vertical scaling in databases?

44. How do you handle time-series data in a database?

45. What are the differences between synchronous and asynchronous replication?

46. How do you implement audit trails and logging in a database?

47. What are some best practices for database indexing?

48. How do you use database constraints to enforce data integrity?

49. What is the role of a database administrator, and how does it differ from a database developer?

50. How do you assess the performance and scalability of a database system?