title: SQL statement with JOIN and WHERE clause
body: <p>I'm new to SQL and trying to solve this problem with two tables Employee and Department. I want display the names of all the employees of 'HR' and 'Sales' departments. 
  Tables  are <strong>Employee (emp_id, emp_name, dept_id)</strong> and <strong>Department (dept_id, dept_name)</strong>.</p>
  
  <p>Thanks!</p>