select DISTINCT
a.EMP_CODE as CODE
,a.EMP_LAST_NAME as SURNAME
,a.EMP_FIRST_NAME as  NAME
from 
(
    select *
    from EMP
    where VALID_FLG='1'
) a
INNER JOIN
(
    select *
    from EMP
    where VALID_FLG='1'
) b
ON
REPLACE(a.EMP_LAST_NAME||a.EMP_FIRST_NAME,' ','')=REPLACE(b.EMP_LAST_NAME||b.EMP_FIRST_NAME,' ','')
and a.EMP_CODE!=b.EMP_CODE
order by 
REPLACE(a.EMP_LAST_NAME||a.EMP_FIRST_NAME,' ','')
,a.EMP_CODE