Query to Get Supervisor Hierarchy using Connect By Clause

SELECT per1.employee_number,

       per1.full_name,

       (    SELECT listagg (' Level:' || LEVEL || ' ' || per.full_name, CHR (10))

                      WITHIN GROUP (ORDER BY LEVEL)

              FROM per_assignments_x paaf, per_people_x per

             WHERE per.person_id = paaf.person_id

        START WITH paaf.person_id = paaf1.supervisor_id

        CONNECT BY paaf.person_id = PRIOR paaf.supervisor_id

                   AND paaf.supervisor_id IS NOT NULL)

          supervisor_levels

  FROM per_all_people_f per1, per_all_assignments_f paaf1

 WHERE     per1.person_id = paaf1.person_id

       AND paaf1.assignment_type = 'E'

       AND paaf1.primary_flag = 'Y'

       AND paaf1.assignment_status_type_id IN (1, 2)

       AND TRUNC (SYSDATE) BETWEEN per1.effective_start_date

                               AND per1.effective_end_date

       AND TRUNC (SYSDATE) BETWEEN paaf1.effective_start_date

                               AND paaf1.effective_end_date

--       AND per1.employee_number = 5925