PostgreSQL: Intermediate SQL CASE WHEN Exercises

This guide is specifically for PostgreSQL syntax.

Intermediate-level SQL CASE WHEN practice exercises with solutions.

Exercise 1

Question: Categorize employees by salary range (Low, Medium, High).

SELECT 
  name,
  salary,
  CASE 
    WHEN salary < 40000 THEN 'Low'
    WHEN salary BETWEEN 40000 AND 70000 THEN 'Medium'
    ELSE 'High'
  END AS salary_category
FROM employees;

CASE WHEN provides if-then-else logic in SQL. ELSE handles all unmatched conditions.

PostgreSQL-Specific Notes

This page covers PostgreSQL syntax. Other databases may have different syntax for similar operations.