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, ' ', '') IN ( 
SELECT REPLACE(EMP_LAST_NAME, ' ', '')  AS SURNAME1
FROM EMP 
WHERE VALID_FLG = '1' 
GROUP BY SURNAME1 
HAVING COUNT(*) >= 2) 

AND REPLACE(EMP_FIRST_NAME, ' ', '') IN ( 
SELECT REPLACE(EMP_FIRST_NAME, ' ', '')  AS NAME1
FROM EMP 
WHERE VALID_FLG = '1' 
GROUP BY NAME1 
HAVING COUNT(*) >= 2) 

ORDER BY SURNAME, CODE