select 
    EMP_CODE as CODE,
    EMP_LAST_NAME as SURNAME,
    EMP_FIRST_NAME as NAME


from EMP

where VALID_FLG = 1

and (replace(SURNAME, " ", ""), replace(NAME, " ", "")) in 
(
    select 
    replace(EMP_LAST_NAME, " ", ""),
    replace(EMP_FIRST_NAME, " ", "")
    
    from EMP
    where VALID_FLG = 1
    and EMP_CODE != CODE
)

;