Add a column, then fill it in SQL
SQL interview exercise on Schema Design, 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.
Add a loyalty_tier column to customers: text, required, 'standard' by default. Then set it to 'gold' for every customer with at least two orders that are not cancelled.
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.