SELECT
    EMP_SEAT2.LINE_ID AS LINE,
    EMP_SEAT2.LAST_SEAT - 2 AS SEAT_F,
    EMP_SEAT2.LAST_SEAT AS SEAT_T
FROM (
    SELECT
        EMP_SEAT1.LINE_ID,
        EMP_SEAT1.NEXT_SEAT + 1 AS LAST_SEAT
    FROM (
            SELECT
                LINE_ID,
                SEAT_NO + 1 AS NEXT_SEAT
            FROM
                SEAT_RESERVE
            WHERE
                RSV_STATUS = 0
        ) AS EMP_SEAT1
        JOIN SEAT_RESERVE
            ON EMP_SEAT1.LINE_ID = SEAT_RESERVE.LINE_ID
            AND EMP_SEAT1.NEXT_SEAT = SEAT_RESERVE.SEAT_NO
            AND SEAT_RESERVE.RSV_STATUS = 0
    ) AS EMP_SEAT2
    JOIN SEAT_RESERVE
        ON EMP_SEAT2.LINE_ID = SEAT_RESERVE.LINE_ID
        AND EMP_SEAT2.LAST_SEAT = SEAT_RESERVE.SEAT_NO
        AND SEAT_RESERVE.RSV_STATUS = 0
ORDER BY
    EMP_SEAT2.LINE_ID DESC,
    EMP_SEAT2.LAST_SEAT ASC