select
    t1.LINE_ID AS LINE
    , t1.SEAT_NO AS SEAT_F
    , t3.SEAT_NO AS SEAT_T
from SEAT_RESERVE t1
inner join SEAT_RESERVE t2 
    on t1.LINE_ID = t2.LINE_ID
    and t1.SEAT_NO + 1 = t2.SEAT_NO
inner join SEAT_RESERVE t3
    on t1.LINE_ID = t3.LINE_ID
    and t1.SEAT_NO + 2 = t3.SEAT_NO
where t1.RSV_STATUS = '0'
and t2.RSV_STATUS = '0'
and t3.RSV_STATUS = '0'
order by t1.LINE_ID desc, t1.SEAT_NO asc