Filter with IN (subquery) in SQL
SQL interview exercise on Subqueries & CTEs, difficulty 2 of 3. Solve it in the editor beside a worked example, or cold in Interview mode with the example hidden; the tests run the moment you do.
Return the customers who have ordered at least one product from the 'Displays' category. Each customer appears once, however many they bought. Column: name. Sorted by name.
Each exercise pairs a worked example with a twin problem to solve in a real editor; the tests run the moment you do. Interview mode hides the example: solve it from memory, without the hint or the solution, and it counts as solved cold. Progress is saved in your browser, and in your account if you sign in.