WITH temp AS (
    SELECT
        REPLACE(emp_last_name, ' ', '') AS emp_last_name
        , REPLACE(emp_first_name, ' ', '') AS emp_first_name
    FROM
        emp
    WHERE
        valid_flg = 1
    GROUP BY
        REPLACE(emp_last_name, ' ', '')
        , REPLACE(emp_first_name, ' ', '')
    HAVING
        COUNT(DISTINCT emp_code) >= 2
)
SELECT
    emp.emp_code AS CODE
    , emp.emp_last_name AS SURNAME
    , emp.emp_first_name AS NAME
FROM
    emp
    INNER JOIN 
        temp
        ON REPLACE(emp.emp_last_name, ' ', '') = temp.emp_last_name
            AND REPLACE(emp.emp_first_name, ' ', '') = temp.emp_first_name
ORDER BY
    REPLACE(emp.emp_last_name, ' ', '')
    , REPLACE(emp.emp_first_name, ' ', '')
    , emp_code