Show the average salary for all departments with more than 3 people for a job.
SELECT job, AVG(Sal) AS AvgSalary FROM Empl GROUP BY job HAVING COUNT(*) > 3;
+----------+-----------+ | job | AvgSalary | +----------+-----------+ | CLERK | 1037.5 | | SALESMAN | 1400 | +----------+-----------+
