Question

我正在研究一个酒店房价系统，而且我正在展示一些我不想要的记录。这是我的表

room id    room_name    rate_starts   rate_ends    single_room   double_room
1          standard     2014-01-01    2014-02-28   150           200
1          standard     2014-03-01    2014-03-05   200           250
1          standard     2014-03-06    2014-03-31   300           350
2          Garden Villa 2014-01-01    2014-02-28   300           400

这是我的MySQL查询

    SELECT room_id, room_name, 
      SUM(`single_room` * DateDiff(
          Least(rate_ends + INTERVAL 1 DAY, '$ends'),
          Greatest(rate_starts, '$starts')
        )) AS Total
    FROM
        room_rate
    WHERE
          hotel_id   = '$hotel_id' AND
          rate_ends >= '$starts' AND
          rate_starts <= '$ends'              
          GROUP BY room_id

这是我的搜索参数($starts)'2014-02-27'到($ends)'2014-03-02'

这是我的结果

Standard room 500
Garden Villa 600

我只搜索单人房价。

其实我不想展示花园别墅因为房价不完整。该房间的日期范围不在2014-03-01至2014-03-05之间。但是它仍然显示第一个日期范围结果。

我希望你能理解我的问题。提前致谢

Answer 1

如果您希望房价在您的起始搜索间隔中，请使用

  WHERE
          hotel_id   = '$hotel_id' AND
          rate_starts>= '$starts' AND -- room rate starts in the search interval
          rate_ends<= '$ends'     --room rate ends in the search interval

我们需要另一种检查可用性的方法表：

room_id, date, running_availability:



select room_id, date,  
  (select sum(availability from (select room_id, rate_starts as date, 1 as availability from     table
  union all
  select room_id, rate_ends, -1 as availability from table) as av2 where av1.date <= av2.date) as running_availability
from
(select room_id, rate_starts as date, 1 as availability from table
union all
select room_id, rate_ends, -1 as availability from table) as av2

现在您可以检查房间是否在您的时间间隔内不可用（running_avaliability！= 0以及开始和结束之间的日期）

如果您想一次性检查价格和可用性，您需要加入这两者。为了便于阅读，让我们将此表称为“可用”

SELECT room_id, room_name, 
  SUM(`single_room` * DateDiff(
      Least(rate_ends + INTERVAL 1 DAY, '$ends'),
      Greatest(rate_starts, '$starts')
    )) AS Total
FROM
    room_rate
    left join 
    (select * from available where running_availability!=1) av 
    on av.date between '$starts' and '$ends'   
WHERE
      hotel_id   = '$hotel_id' AND
      rate_ends >= '$starts' AND
      rate_starts <= '$ends'    
      and av.date is null          
      GROUP BY room_id

为什么我的MySql查询没有返回我想要的返回行？

1 个答案: