Mastering the Nth Highest Salary Problem in SQL – A Key Interview Challenge

 The “Nth Highest Salary” question is one of the most popular and commonly asked problems in SQL-based job interviews. It's not only used to assess your SQL skills but also your logical thinking and understanding of data ranking.

In this blog, we will break down this problem step-by-step using different methods so you can confidently answer it in any interview or real-world scenario.

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Why is the Nth Highest Salary Important?

Many organizations use ranking systems to evaluate performance, bonuses, or salary reports. Knowing how to retrieve the top salaries (like 2nd highest, 3rd highest, etc.) is a vital skill when working with databases.

Let’s say we have the following employees table:

+----+--------+--------+
| id | name   | salary |
+----+--------+--------+
| 1  | Aryan  | 50000  |
| 2  | Riya   | 75000  |
| 3  | Kabir  | 65000  |
| 4  | Sneha  | 90000  |
| 5  | Vivek  | 75000  |
+----+--------+--------+

We want to find, for example, the 3rd highest salary. Let's explore how to do that.

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Method 1: Using LIMIT with OFFSET (MySQL)

This is a simple and straightforward way used in MySQL:

SELECT DISTINCT salary
FROM employees
ORDER BY salary DESC
LIMIT 1 OFFSET 2;

Explanation:

• The ORDER BY salary DESC sorts salaries from highest to lowest.

• OFFSET 2 skips the top 2 results.

• LIMIT 1 selects the next one — the 3rd highest salary.

This method is very readable but mostly limited to MySQL.

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Method 2: Using Subqueries (Universal SQL Approach)

If you are using a database that doesn't support LIMIT and OFFSET, you can use subqueries to find the Nth highest salary:

SELECT MAX(salary)
FROM employees
WHERE salary < (
  SELECT MAX(salary)
  FROM employees
  WHERE salary < (
    SELECT MAX(salary)
    FROM employees
  )
);

This gives the 3rd highest salary. You can add more layers to get the 4th, 5th, etc.

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Method 3: Using DENSE_RANK() Function (Recommended)

Modern SQL databases like PostgreSQL, Oracle, SQL Server, and MySQL 8+ support window functions. Use DENSE_RANK() for a clean solution

SELECT salary
FROM (
  SELECT salary, DENSE_RANK() OVER (ORDER BY salary DESC) AS rank
  FROM employees
) ranked_salaries
WHERE rank = 3;

This approach handles duplicate salaries properly, making it the most accurate method.

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Tips and Best Practices

• Use DENSE_RANK() when available for better readability and accuracy.

• Avoid subquery nesting beyond 3 levels unless necessary for performance.

• Always test with sample data where salaries have duplicates.

• Use DISTINCT when querying raw salary values to avoid duplicates in simple queries.

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Learn SQL Practically with Technogeeks

At Technogeeks, our SQL training program covers real-world problems just like this one. You’ll not only learn how to write queries, but also understand how and why they work.

Our course highlights:

• MySQL, PostgreSQL, Oracle with hands-on labs

• Real-time database projects for practice

• Interview-specific SQL scenarios

• Guidance from industry professionals

Whether you're aiming for a role in Data Analysis, Software Development, or Business Intelligence, our training will prepare you to handle such scenarios with confidence.

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Conclusion

The “Nth Highest Salary” question is not just an interview trick — it represents real business logic. By mastering different SQL techniques like subqueries, DENSE_RANK(), and LIMIT/OFFSET, you’ll enhance your problem-solving skills and become more effective at handling data.