Which supervisor do I have?

In this exercise, we want to get the path from the boss at the top of the hierarchy, to the employees at the bottom of the hierarchy. For this task, we have to combine the information obtained in each step into one field. You can do this by combining the IDs using CAST() from number to string. An example is CAST(ID AS VARCHAR(MAX)) to convert ID of type number to type char.

The task is now to find the path for employees Chris Feierabend with ID=18 and Jasmin Mentil with ID=16 all the way to the top of the organization. The output should look like this: boss_first_level -> boss_second_level .... The IDs of the employees and not their names should be selected.

This exercise is part of the course

Hierarchical and Recursive Queries in SQL Server

View Course

Exercise instructions

Initialize Path to the ID of the supervisor (0) and the start condition of the recursion.
UNION the anchor member and define the recursive member fields (ID, Name, Supervisor).
Add the the ID of the supervisor Supervisor to the Path in each step.
Select the IDs of employees Chris Feierabend and Jasmin Mentil in the CTE.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

WITH employee_Hierarchy AS (
	SELECT
		ID, 
  		NAME,
  		Supervisor,
  		-- Initialize the Path with CAST
  		___('___' AS VARCHAR(MAX)) as Path
	FROM employee
	WHERE Supervisor = 0
	-- UNION the anchor query 
  	___ ALL
    -- Select the recursive query fields
	SELECT 
  		emp.___,
  		emp.___,
  		emp.___,
  		-- Add the supervisor in each step. CAST the supervisor.
        Path + '->' + ___(emp.___ AS VARCHAR(MAX))
	FROM employee emp
		INNER JOIN employee_Hierarchy
  		ON emp.Supervisor = employee_Hierarchy.ID
)

SELECT Path
FROM employee_Hierarchy
-- Select the employees Chris Feierabend and Jasmin Mentil
WHERE ___ = 16 OR ID = ___;

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