SQL prep course
A pattern-by-pattern SQL interview course: 36 problems across 6 patterns, from query basics to window functions and advanced analytics. Follow the arrows — each pattern builds on the ones before it — and tick problems as you solve them so the map fills in and turns green when you finish a pattern.
Query Basics
0 / 6 solved
Joins
0 / 6 solved
Aggregation & Grouping
0 / 6 solved
Subqueries & CTEs
0 / 6 solved
Window Functions
0 / 6 solved
Advanced Patterns
0 / 6 solved
Show the dependency map
✓ Track complete — every pattern solved. Nicely done.
Follow the arrows: finish a topic to unlock what builds on it. Progress is saved on this device.