Question

Write a method to find the number of employees in each department.

Answer

select 
    Dept_Name, 
    Departments.Dept_ID, 
    count(*) as ‘num_employees’
from 
    Departments
left join 
    Employees
on 
    Employees.Dept_ID = Departments.Dept_ID
group by 
    Departments.Dept_ID, Dept_Name