Question

238 viewsSeptember 19, 2024

0

Amit (anonymous) September 19, 2024 0 Comments

What is the purpose of the HAVING clause in SQL, and how does it differ from the WHERE clause?

Write your answer.

score 0 · Answer 1 · 2024-09-19T09:00:30+00:00

HAVING Clause: The HAVING clause is used to filter records after the GROUP BY clause has been applied. It is used with aggregate functions to filter groups of rows based on a condition.
WHERE Clause: The WHERE clause is used to filter records before any grouping occurs. It filters rows based on specified conditions before any grouping or aggregation is done.

Difference:

example:-

— Using WHERE to filter rows before grouping
SELECT department, COUNT(*) as employee_count
FROM employees
WHERE salary > 50000
GROUP BY department;

— Using HAVING to filter groups after grouping
SELECT department, COUNT(*) as employee_count
FROM employees
GROUP BY department
HAVING COUNT(*) > 10;