WITH SEAT_1_3 AS (
     SELECT
          SEAT_1.LINE_ID
         ,SEAT_1.SEAT_NO
         ,SEAT_1.RSV_STATUS
     FROM SEAT_RESERVE AS SEAT_1
          INNER JOIN SEAT_RESERVE AS SEAT_2
              ON SEAT_1.LINE_ID = SEAT_2.LINE_ID
             AND SEAT_1.SEAT_NO = (SEAT_2.SEAT_NO - 1)
          INNER JOIN SEAT_RESERVE AS SEAT_3
              ON SEAT_1.LINE_ID = SEAT_3.LINE_ID
             AND SEAT_1.SEAT_NO = (SEAT_3.SEAT_NO - 2)
     WHERE SEAT_1.RSV_STATUS = '0'
       AND SEAT_2.RSV_STATUS = '0'
       AND SEAT_3.RSV_STATUS = '0'
)
SELECT
     LINE_ID        AS LINE
    ,SEAT_NO        AS SEAT_F
    ,SEAT_NO + 2    AS SEAT_T
FROM SEAT_1_3
ORDER BY LINE_ID DESC, SEAT_F
;