select
emp_code as CODE,
emp_last_name as SURNAME,
emp_first_name as NAME
from emp
where valid_flg='1'
and replace(emp_last_name || emp_first_name,' ','') in(
    select
        replace(emp_last_name || emp_first_name,' ','') as EMP_NAME
    from emp
    where valid_flg='1'
    group by emp_name
    having count(*)>1
    )
order by replace(emp_last_name || emp_first_name,' ',''),code