select
t1.emp_code as CODE,
t1.emp_last_name as SURNAME,
t1.emp_first_name as NAME
from emp as t1
inner join emp as t2
on trim(t1.emp_last_name,' ') = trim(t2.emp_last_name,' ')
and trim(t1.emp_first_name,' ') = trim(t2.emp_first_name,' ')
where t1.valid_flg='1'

order by replace(SURNAME || NAME,' ','') asc,code asc;