Top 10 SQL Interview Questions 2026

If you’re aiming for a tech job in 2026, SQL skills are almost a must-have. Employers value candidates who can work with databases, solve real problems, and handle data smoothly. Whether you’re applying for your first job or moving to a senior role, getting ready with the top 10 SQL interview questions for 2026 can be your game-changer. To help with affordable learning, sites like Udemy offer many courses, and using discount coupons makes it even easier. At ExpertsTeachers.com, you get top-rated courses and study notes at student-friendly prices, so don’t let fees hold you back from success.

Why SQL Interview Preparation Matters in 2026

SQL is a core skill for anyone working with data—be it business analysts, developers, or testers. Every year, the demand for database knowledge keeps growing, but interview patterns also change. New technologies mean employers expect you to know more than just the basics. They look for strong problem-solving, clear logic, and the ability to explain your thought process. That’s why serious SQL interview preparation is now more important than ever.

Top 10 SQL Interview Questions 2026

Want to stand out? Prepare with the most-asked SQL interview questions likely to pop up in 2026. Here are the top ten you should know:

1. What is a JOIN in SQL and how is it used?
2. How do you optimize an SQL query for faster performance?
3. Can you explain the difference between WHERE and HAVING clauses?
4. What is normalization, and why is it important?
5. Describe the process to find duplicate records in a table.
6. How would you delete duplicate rows but keep one instance?
7. What’s the difference between an INNER JOIN and an OUTER JOIN?
8. How do transactions work, and what is ACID?
9. Explain GROUP BY and aggregate functions with an example.
10. What is a subquery, and when should you use it?

Each of these questions spots gaps in your basic and advanced SQL knowledge. Make sure you not only know the answers but can also explain them simply.

Understanding SQL Joins Interview Questions

Joins are among the most common SQL topics in interviews. You should know how to use INNER, LEFT, RIGHT, and FULL joins, along with real-world examples. Here’s what each join does:

INNER JOIN

Returns rows when there’s a match in both tables. If there’s no match, that record is skipped.

LEFT JOIN

Returns all records from the left table, even if there’s no match in the right table. Missing values from the right show as NULL.

RIGHT JOIN

Similar to LEFT JOIN, but returns all records from the right table, plus matching data from the left.

FULL JOIN

Combines the results of both LEFT and RIGHT joins. You get all records when there’s a match in one or both tables.

Common interview question: “Can you write a query to find employees who don’t have any assigned projects using LEFT JOIN?”

Brushing up on SQL joins interview questions will help you tackle most data retrieval and reporting tasks.

Entry-Level SQL Interview Questions

If you’re just starting out, expect more basic questions that test your grasp of fundamentals. Here are a few you might get:

• What is SQL, and why is it used?
• How do you create a table?
• What are primary keys and foreign keys?
• How do you insert, update, and delete data from a table?
• What is a view in SQL?

Entry-level SQL interview questions are your chance to shine if you know the basics. Show you understand not just what to do, but why you do it. Even for simple questions, try to use clear examples.

SQL Interview Questions with Answers 2026

Interviewers may ask questions in new ways, and often want you to show your thinking. Let’s see a couple of “2026 style” SQL interview questions with answers:

Q: How can you improve the speed of a complex SELECT query?

A: You can optimize queries by using indexes, selecting only the columns you need, avoiding SELECT *, reviewing the execution plan, and breaking large queries into smaller steps.

Q: What is the difference between a subquery and a JOIN?

A: A subquery is a query inside another query and is useful when filtering results based on another SELECT statement. A JOIN connects data from two tables based on related columns. Use joins when you want to combine rows, and subqueries when you want to filter or compute values.

By reviewing SQL interview questions with answers 2026, you’ll get familiar with newer approaches and formats. Practice giving answers that are easy to follow and clear.

Quick Tips to Crack SQL Interviews

Cracking an SQL interview is about more than memorizing answers. Follow these quick tips to crack SQL interviews:

• Use smart study notes and mind maps to organize key concepts.
• Practice writing queries by hand—don’t just read them.
• Take mock interviews or solve practice questions online.
• Find sample problems that cover both theory and real-world tasks.
• Review your answers and look for ways to be clearer and more concise.
• Get comfortable with explaining your logic in simple terms.

Study resources from ExpertsTeachers.com include study maps and practical exercises, helping you move beyond theory.

Leveraging Udemy Discount Coupons for SQL Interview Prep

Not everyone can spend big on expensive courses. That’s where platforms like Udemy and ExpertsTeachers.com come in. You can grab Udemy discount coupons that slash course prices so you can get expert guidance without worrying about costs.

How to Find and Use Udemy Discount Coupons

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• Watch for special offers tied to skills in high demand (like SQL, Python, and data analytics).

Recommended SQL Courses for Interview Prep

Some highly-rated SQL interview courses offer deep dives into top 10 SQL interview questions 2026, mock assessments, and hands-on projects. Look for those rated highly by past students and designed for the current year’s hiring trends.

Affordable Learning at ExpertsTeachers.com

ExpertsTeachers.com not only lists discount coupons but also offers ready-made study notes, mind maps, and guidance from industry veterans. Courses start as low as ₹299, making skills training accessible for all, whether you’re prepping for entry-level SQL interview questions or aiming to master advanced SQL joins interview questions.

Conclusion

Getting ready for SQL interviews in 2026 takes focus, planning, and smart learning. Study the top 10 SQL interview questions 2026, master both basics and advanced topics, and use study aids like mind maps and mock tests. Combine these with affordable courses and discount coupons from sites like Udemy and ExpertsTeachers.com for the best results. Ready to get started? Check out the latest deals and start preparing today. Your next big tech job could be just one SQL interview away!