Query : Users, Names, and Supervisors

Tables:
PER_USERS
PER_PERSON_NAMES_F
PER_ALL_PEOPLE_F
PER_ALL_ASSIGNMENTS_M
PER_ASSIGNMENT_SUPERVISORS_F
PER_PERSON_NAMES_F

select a.user_id, a.username, b.first_name, b.last_name
from per_users a, PER_PERSON_NAMES_F b
where a.person_id = b.person_id
and a.username = 'ABCDEFG'

--QUERY2 Supervisor

SELECT ppnf1.full_name "Emp full name",  -- Employee Name
--  papf.person_id ,
--  papf.person_number ,
--  paam.assignment_number ,
 -- paam.assignment_id ,
--  paam.position_id ,
--  pasf.manager_id , -- Manager person_id
  ppnf2.full_name -- Manager Name

FROM Per_all_people_f papf ,
  per_all_assignments_m paam,
  PER_ASSIGNMENT_SUPERVISORS_F pasf,
  PER_PERSON_NAMES_F ppnf1, -- Employee Name
  PER_PERSON_NAMES_F ppnf2  -- Manager Name

WHERE 1=1
AND papf.person_id     = paam.person_id
AND paam.person_id     = pasf.person_id
AND paam.assignment_id = pasf.assignment_id
AND ppnf1.person_id = papf.person_id
AND ppnf1.name_type = 'GLOBAL'
AND ppnf2.person_id = pasf.manager_id
AND ppnf2.name_type = 'GLOBAL'
and ppnf1.full_name like 'Last, First%'

Reference:  https://community.oracle.com/thread/3722850