Question

此代码可以在特定日期内找到可用房间，但无法显示已预订和取消的房间

“酒店”有4个房间，其中1个已预订取消

所以即使我取消了，select方法也会给我3个结果。也许是因为第二个AND仍在运行。基本上我需要的是

检查房间是否在所选日期预订
如果已经预订，请检查是否已取消
如果已取消，或未预订显示。否则不是

SELECT RoomNo, NightCost
FROM room, room_types, booking
WHERE typeid = fk1_typeid
and double_bed=1
and single_bed=0
AND canceled = '1' in 
    (SELECT canceled
     from booking, room_booking
     where bookingid = fk2_bookingid)
AND RoomNo not in 
    (SELECT fk1_RoomNo
     FROM room_booking
     WHERE '2010-04-02' between Check_in 
     and Check_Out or
     '2010-04-03' between Check_in 
     and Check_Out) ;

我试图尽可能清楚，如果需要我会提供更多细节

Answer 1

SELECT  *
FROM    room
JOIN    room_types
ON      typeid = fk1_typeid
WHERE   double_bed = 1
        AND single_bed = 0
        AND roomNo NOT IN
        (
        SELECT  fk1_roomno
        FROM    room_booking
        WHERE   check_out >= '2010-04-02'
                AND check_in <= '2010-04-03'
                AND NOT canceled
        )

Answer 2

如果
，则在2010-04-02和2010-04-04之间占用一个房间
- 某人将在2010-04-03之前办理登机手续。
- 并且有人不会在2010-04-02之前退房
- 并且取消了room_booking。
当房间没有被占用时，房间是免费的

 SELECT R.RoomNo, R.NightCost
   FROM room as R
   JOIN room_types as RT ON RT.typeid = R.fk1_typeid
 WHERE (R.single_bed=0 and R.double_bed=1)
   AND R.roomNo NOT IN (
        SELECT RB.fk1_roomno
          FROM room_booking as RB
         WHERE (RB.check_out >= '2010-04-02')
           AND (RB.check_in  <= '2010-04-03')
           AND NOT (RB.canceled=1)
    )

这正是Quassnoi在我面前所说的..感叹： - ）

如何在mysql中创建条件（使用'if'）？

2 个答案: