with T as (
select 
  EMP_CODE as CODE,
  EMP_LAST_NAME as SURNAME,
  EMP_FIRST_NAME as NAME,
  replace(EMP_LAST_NAME, ' ', '') || replace(EMP_FIRST_NAME, ' ', '') as allname
from EMP
where VALID_FLG == '1'
),
T2 as (
  select allname, count(allname) as c from T
  group by allname
)
select CODE, SURNAME, NAME
from T2 t2
join T t1 on t1.allname == t2.allname 
where c >= 2
;