select EMP_CODE as CODE, EMP_LAST_NAME as SURNAME, EMP_FIRST_NAME as NAME from 
(
select *
from (SELECT *, REPLACE(EMP_LAST_NAME,' ','') as SURNAME, REPLACE(EMP_FIRST_NAME,' ','') as NAME
FROM EMP where VALID_FLG = 1)
inner join (
select SURNAME,NAME
from (SELECT REPLACE(EMP_LAST_NAME,' ','') as SURNAME, REPLACE(EMP_FIRST_NAME,' ','') as NAME
FROM EMP
where VALID_FLG = 1)
group by SURNAME,NAME
having count(*) > 1
) using (SURNAME,NAME)
order by SURNAME,NAME,EMP_CODE
)