PostgreSQL Exercises
Free SQL practice against a real database in the browser, running from simple selects up through joins, aggregates and window functions, with hints and answers. The most efficient way to go from reading SQL to writing it.
Platform
Web Development
Alisdair Owens
10 to 15 hours
Beginner
Free
What it is
A set of graded SQL exercises against a sample club booking database, running in the browser with no setup, each with a hint and a full explanation of the answer.
Why it beats reading a tutorial
SQL is deceptive. The syntax reads like English, which makes it feel understood, and then writing a three table join with a grouped aggregate turns out to be a different skill entirely. Only writing queries closes that gap, and this gives you eighty of them in order of difficulty.
The sections worth finishing
Joins and aggregates, then the window function set. Window functions are where most self taught developers stop, and they are exactly what turns a painful multi query workaround into four lines.
Best for: backend and full stack developers whose SQL is limited to what an ORM generates.
Ready to start?
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Stuck on something specific?
Writing only gets you so far. If you want an answer to your situation rather than the general case, book a session and we will work through it together. Every session is free; a few slots open each week.
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