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Python, SQL & Spark Practice

Write real code against real test cases — right in your browser. Earn XP for every solve, level up from Novice to Grandmaster, and keep your daily streak 🔥 alive. Instant feedback, hints when you're stuck, progress saved automatically.

Python Challenges

10 hands-on challenges with hidden test cases — functions, comprehensions, dicts, stacks and window algorithms. Real Python running in your browser.

Easy → Hard Start practicing →

SQL Practice Challenges

8 hands-on challenges from SELECT basics to window functions and correlated subqueries. Runs entirely in your browser — nothing to install.

Easy → Hard Start practicing →

Spark SQL Challenges

Interview-favorite patterns: dedupe with ROW_NUMBER, running totals, LAG month-over-month, and top-N per group.

Easy → Hard Start practicing →

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Want the theory first? Start with our SQL guides and Spark guides.