CASE Expressions

How can we create conditional if-then-else logic directly inside SQL queries?

Advanced⏱ 3 Minutes⭐ 450 XP

🤔 THE QUESTION

How can we create conditional if-then-else logic directly inside SQL queries?

💡 WHAT IS IT?

CASE expressions evaluate conditions sequentially and return specific scalar values.

🎯 WHAT IS IT USED FOR?

Categorizing metrics, status labels, business tiers, conditional transformations in pipelines.

💻 EXAMPLE

SELECT
name,
salary,
CASE
  WHEN salary >= 100000 THEN 'High'
  WHEN salary >= 50000 THEN 'Medium'
  ELSE 'Low'
END AS salary_level
FROM employees;

Practice typing production-grade SQL code for CASE Expressions.