text: SELECT employee.last_name 
  AS employee, department.name
  FROM department
  LEFT JOIN employee
  ON department.department_id = employee.id
  ORDER BY employee.last_name
  
  
  SELECT department.id
  FROM department
  LEFT JOIN roles
  ON roles.department_name = department.id
  
  
  SELECT roles.id, role_title, role_salary, department_name
  FROM roles
  LEFT JOIN departments
  ON roles.department_id = department.id
  
  
  SELECT employees.id, first_name, last_name, role_title 
  FROM employees 
  LEFT JOIN roles 
  ON employees.role_id = role_id 
  ORDER BY employees.last_name