Be ready for job interviews with practical and conceptual questions.

🔹 Basic Interview Questions

1. What is the difference between WHERE and HAVING?
2. Define the difference between PRIMARY KEY and UNIQUE KEY.
3. What is a Foreign Key? Explain with an example.
4. What is the purpose of the NOT NULL constraint?
5. What are the different types of SQL JOINs in MySQL?
6. How is TRUNCATE different from DELETE?
7. What does SELECT DISTINCT do?
8. What is the default port used by MySQL?
9. Explain the role of the DEFAULT keyword in column definition.
10. What is a view in MySQL and why is it used?

🔹 Intermediate Interview Questions

1. How do indexes improve the performance of queries?
2. What is the use of AUTO_INCREMENT in MySQL?
3. What is normalization? Name the different normal forms.
4. Explain the difference between CHAR and VARCHAR.
5. What is a stored procedure? How is it different from a function?
6. Explain the purpose of GROUP BY with an example.
7. What is a composite key? Give an example.
8. What is the difference between INNER JOIN and LEFT JOIN?
9. What are transactions in MySQL?
10. How do you back up and restore a MySQL database?

🔹 Advanced Interview Questions

1. Explain how replication works in MySQL.
2. What are locks in MySQL and how do they affect transactions?
3. What is the difference between table-level locking and row-level locking?
4. What is a trigger? Provide a use case where it’s beneficial.
5. What are the ACID properties of a transaction?
6. What is query optimization and why is it important?
7. How do partitioned tables work in MySQL?
8. What is the difference between logical backup and physical backup?
9. What is a full-text index and when would you use one?
10. What are deterministic and non-deterministic functions in MySQL?

🔹 Expert/Real-World Scenario Questions

1. How would you handle deadlocks in a multi-user environment?
2. What steps would you take to diagnose a slow query?
3. Explain the master-slave replication setup. What are its limitations?
4. How can you prevent SQL injection in MySQL?
5. What would you do if a user accidentally dropped a production table?
6. How can you implement data archiving in MySQL?
7. What is the use of EXPLAIN in query optimization?
8. How do you secure a MySQL server in a production environment?
9. What are the effects of running MySQL in autocommit mode?

When would you use MERGE tables or partitioning over normal tables?