SQL CTEs Practice Problems

A CTE (WITH clause) names an intermediate result set so the next step can query it like a table, turning a nested mess into a readable pipeline. Interviewers at data-heavy companies expect them for any multi-step transformation - compute per-group stats in one CTE, filter or join against them in the next. Chained CTEs are also how you keep your reasoning legible under whiteboard pressure.

6 problems across 4 schemas · Premium. Each runs your query in an isolated SQLite sandbox with instant, graded feedback.