select
emp_code as CODE,
emp_last_name as SURNAME,
emp_first_name as NAME
from emp as x
where exists (
    select y.emp_code from emp as y
    where y.emp_code <> x.emp_code AND VALID_FLG = '1'
    and REPLACE(y.emp_last_name, ' ', '') = REPLACE(x.emp_last_name, ' ', '')
    and REPLACE(y.emp_first_name, ' ', '') = REPLACE(x.emp_first_name, ' ', '')
) AND VALID_FLG = '1'
order by REPLACE(x.emp_last_name, ' ', ''), REPLACE(x.emp_first_name, ' ', ''), x.emp_code