How to use the CASE operator in SQL?

The CASE operator is used to implement conditional logic in SQL queries. It allows you to return values based on conditions, similar to the IF-ELSE statement.

MySQL 8.1
CASE
    WHEN condition1 THEN result1
    WHEN condition2 THEN result2
    ...
    ELSE default_result
END

Examples

• Assigning categories based on salary:

  MySQL 8.1
  SELECT name,
      salary,
      CASE
          WHEN salary >= 80000 THEN 'High'
          WHEN salary >= 50000 THEN 'Medium'
          ELSE 'Low'
      END AS salary_category
  FROM employees;