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These problems ask for a query rather than code, covering the joins, grouping, window functions, and index reasoning that data-adjacent loops screen for. They pair directly with the SQL Playground, where you write queries against seeded databases and get graded on the result set. Increasingly common in backend loops, not just data roles.
A schema and a question about the data rather than a function signature.
25 problems. Each one runs in an in-browser editor against real test cases, with hints and a worked solution.
The patterns cheat sheet covers all of these in one page - what each one looks like in a problem statement, and the template that follows.