SQL coding challenges
Breakpoint lists 10 sites to practise SQL on, link-checked every 12 hours. Updated 26 Oct 2026.
SQL practice sites give you real-looking tables and ask questions about them: join these, group those, find the top customers by month. The best ones are built around data and analytics interviews, with questions taken from the kind companies actually ask, and they let you pick the database dialect you'll be using.
Start with basic SELECT, WHERE and GROUP BY questions, then move to joins, window functions and common table expressions, which most interview questions need. Dialects differ in small ways, especially dates and string functions, so practise in the one your job or interview uses. Each row below notes the dialects a site supports. Write each query out before running it, then check the result by hand on a few rows; interviewers care about reasoning as much as the answer.
Rather learn by playing? SQL games (11) →
- StrataScratchTrack · Interview prep · FreemiumSQL questions with PostgreSQL, MySQL and other engines
- DataLemurTrack · Interview prep · FreemiumSQL interview questions run on PostgreSQL
- ExercismTrack · Challenge platformsSQL track runs on SQLite: 81 exercises, free mentoring
- HackerRankTrack · Interview prepSQL domain: 58 challenges; MySQL, Oracle, SQL Server, DB2
- LeetCodeTrack · Interview prep · FreemiumSQL 50 study plan; MySQL, MS SQL Server, Oracle, PostgreSQL
- CodeChefTrack · Competitive programmingLearn SQL course; SQL judged on SQLite
- CodeSignalTrack · Interview prep · FreemiumSQL paths, including PostgreSQL data analysis
- CodewarsJudge · Challenge platformsSQL kata run on PostgreSQL
- code.golfJudge · Challenge platformsSQL on SQLite 3.54
- CoderbyteJudge · Challenge platforms · FreemiumDatabase challenges written in SQL
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SQL coding challenges: common questions
Where can I practise SQL for data interviews?
- Sites built around interview questions, such as StrataScratch and DataLemur, plus the database sections of LeetCode and HackerRank. They use realistic tables and questions.
Which SQL dialect should I practise?
- The one you'll use: PostgreSQL and MySQL are the most common on these sites. The note on each row says which dialects it supports.
Are window functions really needed?
- For data and analytics interviews, yes: ranking, running totals and month-over-month questions all use them. Practise them after you're comfortable with joins and GROUP BY.
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