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 || EMP_FIRST_NAME, ' ','') IN(
  
    SELECT
      REPLACE(EMP_LAST_NAME || EMP_FIRST_NAME, ' ','') AS EMP_NAME
    FROM
      EMP
    WHERE
      VALID_FLG = '1'
    GROUP BY 
      EMP_NAME
    HAVING
      COUNT(*) >= 2
   )
ORDER BY
  REPLACE(EMP_LAST_NAME || EMP_FIRST_NAME, ' ','') ASC,
  EMP_CODE ASC