Practice more. Guess less.
Try 4 questions free without an account. Then explore the whole library for seven days, with no card needed.
€0
See how learning by doing feels.
- 4 free exercises
- Immediate feedback
- Real queries on sample company data
€10/ month
Full access to the current library.
- 136 exercises in 20 courses and tracks
- 6 role-based interview tracks
- About 12 hours for a first pass
- Saved progress and unlimited replay
- New lessons as released
€49/ year
€4.08 per month, billed yearly.
- Everything in Monthly
- Save €71 versus twelve monthly payments
- One payment for a year
Every exercise asks you to write SQL, run it against sample company data, and check the result. You can see how each answer is graded and explore the full library during your trial.
Good to know
How far can I go in a month?
The entire current library is available immediately. The listed 740 minutes are first-pass estimates; time varies with retries and reading. Replay is unlimited while access is active.
Is interview practice included?
Yes. All 6 role tracks are included in the same subscription. The first junior engineer interview question is free without an account.
Does the seven-day trial need a card?
No. It starts when you create an account. When it ends, your progress stays saved and the full library becomes locked until you subscribe.
Do I need to install a database?
No. Queries run on sample company data on our servers. You never connect your own databases.
Will this SQL work at my job?
The core patterns transfer. These exercises run in SQLite; PostgreSQL, MySQL, BigQuery and Snowflake differ in functions, dates and data types, so check your database documentation when adapting a query.