SELECT 
    LINE_ID AS LINE,
    SEAT_NO AS SEAT_F,
    SEAT_NO + 2 AS SEAT_T
FROM (
    SELECT 
        LINE_ID,
        SEAT_NO,
        RSV_STATUS,
        LEAD(RSV_STATUS, 1) OVER (PARTITION BY LINE_ID ORDER BY SEAT_NO) AS LEAD_STATUS_1,
        LEAD(RSV_STATUS, 2) OVER (PARTITION BY LINE_ID ORDER BY SEAT_NO) AS LEAD_STATUS_2
    FROM SEAT_RESERVE
)
WHERE 
    RSV_STATUS = '0'
    AND LEAD_STATUS_1 = '0'
    AND LEAD_STATUS_2 = '0'
ORDER BY
    LINE DESC,
    SEAT_F
;