• select * from Employee where boss_id = x_id: Loop is driven by the employees who work for x_id directly.

  • return next e: Return one of those employees, (i.e., append to the eventual output).

  • return query: Also return the employees who work for e

  • select * from works_for(e.emp_id): Recursive call, to get the employees who work for e.emp_id, directly or indirectly.