Cracking SQL interviews just got easier! This guide explores all SQL LeetCode problems, from basic queries to advanced joins.
Whether you’re a beginner or refining your skills, this blog unlocks the secrets to solving LeetCode SQL problems like a pro.
Table of Contents
1. All SQL LeetCode Problems
All SQL LeetCode problems are coding challenges focused on SQL concepts like queries, joins, aggregations, and subqueries. These range from easy (e.g., filtering data) to hard (e.g., complex window functions).
Popular examples include Second Highest Salary, Department Top Three Salaries, and Customers Who Never Order.
2. Why Practice LeetCode SQL Questions?
- Interview prep: Top companies like Google and Amazon test SQL skills rigorously.
- Pattern recognition: Learn recurring themes like ranking functions, pivoting tables, and nested queries.
- Speed and accuracy: SQL problems often have tight time limits in coding rounds.
3. Top 5 Categories of LeetCode SQL Problems
- Basic Queries: SELECT, WHERE, ORDER BY.
- Joins: INNER JOIN, LEFT JOIN, self-joins.
- Aggregations: GROUP BY, HAVING, COUNT/SUM.
- Subqueries & CTEs: Nested queries and Common Table Expressions.
- Window Functions: RANK(), ROW_NUMBER(), PARTITION BY.
4. Tips for Solving LeetCode SQL Problems
- Understand the schema: Always analyze table relationships first.
- Test edge cases: Handle NULL values, duplicates, and empty results.
- Optimize queries: Avoid nested loops; use window functions for efficiency.
List of all Leetcode Problem
1. Easy Problems
2. Medium Problems
3. Hard Problems
All SQL LeetCode Questions
| S.No. | Name | Level of Question | Solution |
| 1 | Product Sales Analysis I | Easy | Link |
| 2 | Delete Duplicate Emails | Easy | Link |
| 3 | Running Total for Different Genders | Medium | Link |
| 4 | Human Traffic of Stadium | Hard | Link |
| 5 | Department Top Three Salaries | Hard | Link |
| 6 | Trips and Users | Hard | Link |
| 7 | Team Scores in Football Tournament | Medium | Link |
| 8 | Highest Grade for Each Student | Medium | Link |
| 9 | Number of Transactions Per Visit | Hard | Link |
| 10 | List the Products Ordered in a Period | Easy | Link |
| 11 | Ads Performance | Easy | Link |
| 12 | Restaurant Growth | Medium | Link |
| 13 | Report Contiguous Dates | Hard | Link |
| 14 | Find the Team Size | Easy | Link |
| 15 | Weather Type in Each Country | Easy | Link |
| 16 | Find the Start and End Number of Continuous Ranges | Medium | Link |
| 17 | Students and Examinations | Easy | Link |
| 18 | All People Report to the Given Manager | Medium | Link |
| 19 | Page Recommendations | Medium | Link |
| 20 | Average Selling Price | Easy | Link |
| 21 | Number of Comments Per Post | Easy | Link |
| 22 | Queries Quality and Percentage | Easy | Link |
| 23 | Last Person to Fit in the Bus | Medium | Link |
| 24 | Monthly Transactions I | Medium | Link |
| 25 | Reformat Department Table | Easy | Link |
| 26 | Product Price at a Given Date | Medium | Link |
| 27 | Immediate Food Delivery I | Easy | Link |
| 28 | Immediate Food Delivery II | Medium | Link |
| 29 | Article Views I | Easy | Link |
| 30 | Active Businesses | Medium | Link |
| 31 | Reported Posts | Easy | Link |
| 32 | User Activity for the Past 30 Days II | Easy | Link |
| 33 | User Activity for the Past 30 Days I | Easy | Link |
| 34 | Sales Analysis III | Easy | Link |
| 35 | Sales Analysis II | Easy | Link |
| 36 | Sales Analysis I | Easy | Link |
| 37 | Project Employees III | Medium | Link |
| 38 | Project Employees II | Easy | Link |
| 39 | Swap Salary | Easy | Link |
| 40 | Project Employees I | Easy | Link |
| 41 | Product Sales Analysis III | Medium | Link |
| 42 | Product Sales Analysis II | Easy | Link |
| 43 | Actors and Directors who Cooperated at Least Three times | Easy | Link |
| 44 | Customers who Bought All Products | Medium | Link |
| 45 | Exchange Seats | Medium | Link |
| 46 | Not Boring Movies | Easy | Link |
| 47 | Biggest Single Number | Easy | Link |
| 48 | Customers Who Bought All Products | Medium | Link |
| 49 | Shortest Distance in a Plane | Medium | Link |
| 50 | Triangle Judgement | Easy | Link |
| 51 | Tree Node | Medium | Link |
| 52 | Sales Person | Easy | Link |
| 53 | Consecutive Available Seats | Easy | Link |
| 54 | Friend Requests I Overall Acceptance Rate | Easy | Link |
| 55 | Classes More than 5 Students | Easy | Link |
| 56 | Big Countries | Easy | Link |
| 57 | Customer Placing the Largest Number of Orders | Easy | Link |
| 58 | Find Customer Referee | Easy | Link |
| 59 | Employee Bonus | Easy | Link |
| 60 | Managers with at Least 5 Direct Reports | Medium | Link |
| 61 | Game Play Analysis III | Medium | Link |
| 62 | Nth Highest Salary | Medium | Link |
| 63 | Rank Scores | Medium | Link |
| 64 | Consecutive Numbers | Medium | Link |
| 65 | Employees Earning more than their Managers | Easy | Link |
| 66 | Duplicate Emails | Easy | Link |
| 67 | Second Highest Salary | Medium | Link |
| 68 | Customers Who Never Order | Easy | Link |
| 69 | Game Play Analysis I | Easy | Link |
| 70 | Game Play Analysis II | Easy | Link |
| 71 | Rising Temperature | Easy | Link |
| 72 | Employees Earning More Than Their Managers | Easy | Link |
FAQs
1. How many SQL problems are on LeetCode?
As of 2023, LeetCode hosts ~150 SQL questions, with new additions monthly.
2. Do I need a LeetCode Premium account for SQL practice?
No! Most SQL problems are free, but Premium offers company-specific filters.
3. What are the most common SQL topics asked in interviews?
Joins, aggregations, and window functions dominate technical screens.
4. How long does it take to master LeetCode SQL questions?
With daily practice, 2–4 weeks for basics, 6–8 weeks for advanced topics.
5. Are LeetCode SQL problems similar to real interviews?
Yes! Companies often reuse or adapt these questions for coding rounds.
Conclusion
Mastering all SQL LeetCode problems is a game-changer for acing data-driven interviews. Focus on core topics, practice daily, and leverage free resources to build confidence.
Ready to tackle LeetCode SQL questions? Start coding today! 💻
Happy Reading…