Find the second highest salary from the employees table.
This challenge now meets the current minimum standard for sitemap inclusion and independent indexing.
Find the second highest salary from the employees table.
This is one of the most common SQL interview questions because it forces you to think about distinct value tiers instead of raw row counts. The same pattern appears in leaderboards, pricing analysis, and compensation reports where the business question is about the second highest unique value, not just the second row after sorting.
idsalarySELECT
MAX(salary) AS second_highest
FROM employees
WHERE salary < (
SELECT MAX(salary)
FROM employees
)The inner query finds the global maximum salary. The outer query then restricts the table to salaries below that maximum and takes the maximum of the remaining values. This is compact, easy to explain in an interview, and works well when you only need the second distinct tier.
WITH ranked_salaries AS (
SELECT
salary,
DENSE_RANK() OVER (ORDER BY salary DESC) AS salary_rank
FROM employees
)
SELECT
MAX(salary) AS second_highest
FROM ranked_salaries
WHERE salary_rank = 2DENSE_RANK makes the uniqueness rule explicit by assigning the same rank to tied salary values. This is more verbose than the nested MAX version, but it scales naturally if the follow-up asks for the third, fourth, or top N distinct salary tiers.
The most common mistake is using ORDER BY salary DESC LIMIT 1 OFFSET 1 on the raw table. That returns the second row, not the second distinct salary, so duplicate top salaries break the answer. Another mistake is forgetting that the correct result may be NULL when there is no second unique salary.
ROW_NUMBER numbers physical rows, so duplicate top salaries would get rank 1 and 2 even though they are the same salary value. DENSE_RANK collapses ties into the same tier, which matches the business meaning of second highest distinct salary.
There is no second distinct salary. The nested MAX approach returns NULL because the filtered set is empty, which is the correct result for this question shape.
Use these guides when you want the fuller explanation behind the SQL pattern this challenge is testing.
Unlock the power of nested queries. Learn when to use subqueries in SELECT, WHERE, and FROM clauses with practical, runnable examples.
Master ROW_NUMBER, RANK, and running totals with interactive visualizations. See exactly how window functions process your data row by row.
Building leaderboards, finding top performers, or paginating results? Master the three SQL ranking functions and understand exactly when to use each one.
If this problem exposed a deeper weakness, use a topic hub to move through a curated cluster instead of random article hopping.
If you want the rotating practice flow, open this same question from the daily stream. If you want interview-style packaging, continue into the interview pool after this rep.
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