WITH T1 AS(
    SELECT
        LINE_ID,
        SEAT_NO,
        SUM(1 - RSV_STATUS) OVER(
            PARTITION BY LINE_ID
            ORDER BY SEAT_NO
            ROWS BETWEEN 0 FOLLOWING AND 2 FOLLOWING
        ) AS CNT
    FROM
        SEAT_RESERVE
), T2 AS(
    SELECT
        LINE_ID AS LINE,
        SEAT_NO AS SEAT_F,
        SEAT_NO + 2 AS SEAT_T
    FROM
        T1
    WHERE
        CNT = 3
    ORDER BY
        LINE DESC,
        SEAT_F ASC
)
SELECT
    *
FROM
    T2