Learn SQL

Work through the lessons in order. Each one unlocks the next.

1. 0Lesson 0 · Level 0How to read a table
2. 🔒Lesson 1 · Level 1SELECT, columns, DISTINCTFinish the previous lesson to unlock
3. 🔒Lesson 2 · Level 1WHERE with numbers: AND, OR, BETWEENFinish the previous lesson to unlock
4. 🔒Lesson 3 · Level 1WHERE with text, ORDER BY, LIMITFinish the previous lesson to unlock
5. 🔒Lesson 4 · Level 1Review: The Sneaker StoreFinish the previous lesson to unlock
6. 🔒Lesson 5 · Level 2NULL values, calculations, ASFinish the previous lesson to unlock
7. 🔒Lesson 6 · Level 2Text and date functionsFinish the previous lesson to unlock
8. 🔒Lesson 7 · Level 2CASE WHEN: making categoriesFinish the previous lesson to unlock
9. 🔒Lesson 8 · Level 2Review: The Delivery AppFinish the previous lesson to unlock
10. 🔒Lesson 9 · Level 3COUNT, SUM, AVG, MIN, MAXFinish the previous lesson to unlock
11. 🔒Lesson 10 · Level 3GROUP BY: summarising each groupFinish the previous lesson to unlock
12. 🔒Lesson 11 · Level 3HAVING, and the order SQL runs things inFinish the previous lesson to unlock
13. 🔒Lesson 12 · Level 3Review: The Player ReportFinish the previous lesson to unlock
14. 🔒Lesson 13 · Level 4INNER JOIN basicsFinish the previous lesson to unlock
15. 🔒Lesson 14 · Level 4JOINs with filters and groupingFinish the previous lesson to unlock
16. 🔒Lesson 15 · Level 4LEFT JOIN: finding what's missingFinish the previous lesson to unlock
17. 🔒Lesson 16 · Level 4Joining three tablesFinish the previous lesson to unlock
18. 🔒Lesson 17 · Level 4Review: The Game Store ReportFinish the previous lesson to unlock
19. 🔒Lesson 18 · Level 5Subqueries: a query inside a queryFinish the previous lesson to unlock
20. 🔒Lesson 19 · Level 5WITH (CTEs): breaking big queries into stepsFinish the previous lesson to unlock
21. 🔒Lesson 20 · Level 5Changing data: INSERT, UPDATE, DELETEFinish the previous lesson to unlock
22. 🔒Lesson 21 · Level 5Final Case Study: The Campus Merch ShopFinish the previous lesson to unlock