Query to fetch Line Manager of Employee

SELECT 

  papf.person_number AS EMPLOYEE_NUMBER, 

  ppn_lm.display_name LINE_MANAGER_NAME 

FROM 

  per_assignment_supervisors_f pasf_lm, 

  per_person_names_f ppn_lm, 

  per_all_people_f papf A

WHERE 

  1 = 1 

  AND pasf_lm.person_id = papf.person_id 

  AND pasf_lm.manager_type = 'LINE_MANAGER' 

  AND SYSDATE BETWEEN pasf_lm.effective_start_date 

  AND pasf_lm.effective_end_date 

  AND pasf_lm.manager_id = ppn_lm.person_id 

  AND ppn_lm.name_type = 'GLOBAL' 

  AND SYSDATE BETWEEN ppn_lm.effective_start_date 

  AND ppn_lm.effective_end_date 

  AND SYSDATE BETWEEN papf.effective_start_date 

  AND papf.effective_end_date