Database Basics 0. What is a database? 1. What is an SQL query? 2. NULL Values

Getting Started 3. Our Data 4. Your First Query 5. The From Clause 6. The Where Clause 7. The Order By Clause

SQL Operators 8. Distinct 9. Equality and Inequality 10. Between and Not Between 11. In and Not In 12. Exists and Not Exists 13. Math and Text 14. Dates 15. Like 16. Case statements 17. Checking for NULL

Aggregate Functions 18. What are aggregates? 19. Group By 20. sum() 21. min() and max() 22. avg() 23. count() 24. Having

Joins 25. What is a join? 26. Thinking about Joins 27. Inner Join 28. Left Join 29. Multiple Joins

Subqueries 30. What is a Subquery? 31. Subquery in Where Clause 32. Subquery in From Clause 33. Common Table Expressions

Set Operations 34. What Are Set Operations? 35. Union and Union All 36. Intersect 37. Except/Minus

Window Functions 38. What are Window Functions? 39. row_number() 40. lead() and lag() 41. Windowed Aggregates

Coding Best Practices 42. Know Your Data 43. Comments 44. Style

Extras SQL Console Resources Feedback Acknowledgements

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Aggregate Functions