Learn SQL by Solving Murders

Query the Murder is a SQL learning game where the exercises are murder investigations. Instead of abstract test cases, you’re querying a real database of suspects, alibis, and evidence — with an actual answer to find.

It’s more motivating than a textbook, faster than a video course, and more memorable than practice problems that don’t go anywhere.

What you’ll learn

The 18 cases cover SQL from beginner to intermediate level:

• Filtering and sorting — SELECT, WHERE, ORDER BY, LIMIT
• Combining tables — INNER JOIN, LEFT JOIN, multi-table joins
• Aggregation — GROUP BY, HAVING, COUNT, SUM, AVG
• Nested queries — subqueries, correlated subqueries
• CTEs — WITH clauses for readable multi-step logic
• Window functions — ROW_NUMBER, RANK, LAG in advanced cases

Why it works for learning

Most SQL practice suffers from the same problem: there’s no reason to care about the answer. Query the Murder fixes that. When the question is “who had access to the estate between 9pm and midnight?”, your JOIN suddenly matters. The feedback loop is immediate — submit a query, see real rows come back, iterate.

Each case also keeps the schema visible at all times, so you’re not memorising table structures — you’re using them.

How to start

Go to the cases page and pick Case 1. It’s designed for complete beginners — if you know what SELECT * FROM table does, you have enough to get started. Cases get progressively harder from there.

Reading while you practise

Some SQL confusion is faster to clear up by reading than by trial and error. SQL order of execution explains why SELECT runs sixth rather than first — and why that single fact resolves the three errors beginners hit most often.