ระบุตำแหน่งในลำดับชั้น

WITH employee_hierarchy AS (
	SELECT
		ID, 
  		NAME,
  		Supervisor,
  		-- Initialize the field LEVEL
  		___ as LEVEL
	FROM employee
  	-- Start with the supervisor ID of the IT Director
	WHERE ___ = ___
	UNION ALL
	SELECT 
  		emp.ID,
  		emp.NAME,
  		emp.Supervisor,
  		-- Increment LEVEL by 1 each step
  		___ + 1
	FROM employee emp
		JOIN employee_hierarchy
  		-- JOIN on supervisor and ID
  		ON emp.___ = employee_hierarchy.___)
    
SELECT 
	cte.Name, cte.Level,
    emp.Name as ManagerID
FROM employee_hierarchy as cte
	JOIN employee as emp
	ON cte.Supervisor = emp.ID 
ORDER BY Level;