Cheatsheet Pages / SQL Cheatsheet
How to check that a related row exists in SQL — EXISTS
You only care whether a matching row exists at all — departments with at least one employee earning over 100k.
Every example runs against the cheatsheet's sample tables — departments(id, name), employees(id, name, dept_id, salary, manager_id, hired_on) and orders(id, emp_id, amount, ordered_on) — and was executed and verified against SQLite, so you can paste it in and get the same result.
SELECT d.name FROM departments d
WHERE EXISTS (SELECT 1 FROM employees e WHERE e.dept_id = d.id AND e.salary > 100000);
-- Engineering: departments with at least one employee earning over 100k.
-- EXISTS only cares whether a row exists — a common pick for large tables