What is a conditional aggregation in SQL?

Conditional aggregation allows you to apply aggregate functions to a subset of data that

meets a certain condition. This is usually done with a CASE expression.

Example:

SELECT department,

SUM(CASE WHEN gender = 'M' THEN 1 ELSE 0 END) AS male_count,

SUM(CASE WHEN gender = 'F' THEN 1 ELSE 0 END) AS female_count

FROM employees

GROUP BY department;

This query counts the number of male and female employees in each department.