What is the HAVING clause?

The HAVING clause is used in SQL to filter the results of groups created by the GROUP BY clause.

Differences from WHERE:

• WHERE filters individual rows before grouping.
• HAVING filters groups after they are created and after applying aggregate functions.

Syntax:

SELECT column1, column2, ...
FROM table_name
WHERE condition
GROUP BY column1, column2, ...
HAVING group_condition
ORDER BY column1, column2, ...;

Example: Select departments where the average salary exceeds 50,000.

SELECT department, AVG(salary) AS avg_salary
FROM employees
GROUP BY department
HAVING AVG(salary) > 50000;