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Top 77 MySQL / SQL Interview Questions & Answers (2026)

77 Questions 39 Beginner 23 Intermediate 15 Advanced

About MySQL / SQL

Top 100 MySQL and SQL interview questions covering queries, joins, indexes, transactions, normalization, stored procedures, and performance optimization. Companies hiring for MySQL / SQL roles test this knowledge at every stage — from first-round screens that check the basics to final-round conversations about real-world trade-offs.

What to Expect in a MySQL / SQL Interview

Expect a mix of conceptual and practical MySQL / SQL questions: clear definitions and core-concept checks for junior roles, hands-on scenario questions for mid-level roles, and architecture or trade-off discussions for senior roles. Interviewers usually move from foundational topics toward the kind of problems you'd actually face on the job.

How to Use This Guide

Work through the MySQL / SQL questions in order — Beginner, then Intermediate, then Advanced — so each concept builds on the last. Every question has its own page; bookmark the ones that trip you up and revisit them the day before your interview.

Curated by Tech Baithak Editorial Team  ·  Last updated: May 2026

Beginner 39 questions

Core concepts every MySQL / SQL developer must know.

01 What is SQL? 02 What is a relational database? 03 What is the difference between a database and a table? 04 What is a primary key? 05 What is a foreign key? 06 What is the SELECT statement? 07 What is the WHERE clause? 08 What are SQL data types in MySQL? 09 What is INSERT, UPDATE, and DELETE in SQL? 10 What is the difference between DELETE and TRUNCATE? 11 What are SQL aggregate functions? 12 What is GROUP BY in SQL? 13 What is the ORDER BY clause? 14 What is LIMIT and OFFSET in MySQL? 15 What are SQL constraints? 16 What is NULL in SQL and how do you handle it? 17 What is the difference between CHAR and VARCHAR? 18 What is the LIKE operator in SQL? 19 What is an alias in SQL? 20 What is a JOIN in SQL? 21 What is the difference between INNER JOIN and LEFT JOIN? 22 What is a subquery in SQL? 23 What is the UNION operator in SQL? 24 What is the difference between HAVING and WHERE? 25 What is normalization in databases? 26 What is denormalization? 27 What is an index in SQL? 28 What is the difference between a clustered and non-clustered index? 29 What is a VIEW in SQL? 30 What is a stored procedure in MySQL? 31 What is a trigger in MySQL? 32 What is a transaction in SQL? 33 What are ACID properties in databases? 34 What are transaction isolation levels in MySQL? 35 What is the difference between MyISAM and InnoDB? 36 What is the AUTO_INCREMENT attribute in MySQL? 37 What is the MySQL EXPLAIN command? 38 What is the difference between UNION and UNION ALL? 39 What is a composite key?
Back to All Topics 77 questions total