我正在尝试以 1 小时为增量获得酒店房间的可用性。例如,如果房间是从上午 9 点到上午 10 点预订的,从上午 12 点到下午 3 点预订的,我正在尝试获取 available_from 到 available_to 之间所有其他时间的 1 小时增量
我可以在桌子上留下加入并获得房间可用性,但不是时间段。
这是我的相关架构:
旅馆:
Id | name
保留:
Id | hotel_id | room_id | start | end | status
房间:
Id | hotel_id | name | number | available_from | available_to
这是我到目前为止的查询:
SELECT r.id, r.name, r.number, r.type, r.rating
FROM rooms r
LEFT OUTER JOIN reservations res ON res.room_id = r.id
AND CURRENT_TIMESTAMP BETWEEN r.available_from AND r.available_to
GROUP BY r.id, r.type
例:
(这是我试图从数据库中获取的数组。忽略属性名称):
[{"房间号":1,"可用时间":["2019-01-01 00:00:00","2019-01-01 01:00:00","2019-01-01 02:00:00","2019-01-01 03:00:00","2019-01-01 04:00:00","2019-01-0105:00:00","2019-01-01 06: 00:00","2019-01-01 07:00:00","2019-01-01 08:00:00","2019-01-01 09:00:00","2019-01-01 10:00:00","2019-01-01 11:00:00","2019-01-01 12:00:00","2019-01-01 13:00:00","2019-01-01 14:00:00","2019-01-01 15:00:00","2019-01-01 16:00:00","2019-01-01 17:00:00","2019-01-01 18:00:00",">
2019-01-01 19:00:00","2019-01-01 20:00:00","2019-01-01 21:00:00","2019-01-01 22:00:00","2019-01-01 23:00:00"]}]
我尝试了以下方法:
SELECT free_from, free_until
FROM (
SELECT a.end AS free_from,
(SELECT MIN(c.start)
FROM reservations c
WHERE c.start > a.end) as free_until
FROM reservations a
WHERE NOT EXISTS (
SELECT 1
FROM reservations b
WHERE b.start BETWEEN a.end AND a.end + INTERVAL 1 HOUR
)
AND a.end BETWEEN '2019-01-03 09:00' AND '2019-01-03 21:00'
) as d
ORDER BY free_until-free_from
LIMIT 0,3;
但是我只返回一行,结果也是不正确的。如何解决这个问题?
示例数据:
旅馆:
1 | Marriott
保留:
1 | 1 | 1 | 2019-01-03 15:00:00 | 2019-01-03 17:00:00 | Confirmed
1 | 1 | 1 | 2019-01-03 18:00:00 | 2019-01-03 20:00:00 | Confirmed
房间:
1 | 1 | "Single" | 528 | 09:00:00 | 21:00:00
预期成果
房间编号 |房间名称 |可用时间
1 | "Single" | 2019-01-03 09:00:00, 2019-01-03 10:00:00, 2019-01-03 11:00:00, 2019-01-03 12:00:00, 2019-01-03 13:00:00, 2019-01-03 14:00:00, 2019-01-03 17:00:00, 2019-01-03 20:00:00, 2019-01-03 21:00:00, 2019-01-03 22:00:00, 2019-01-03 23:00:00, 2019-01-03 24:00:00
如果将Times_Slots表添加到数据库中,如以下 SQL Fiddle 所示:
CREATE TABLE Time_Slots
(`Slot` time);
INSERT INTO Time_Slots
(`Slot`)
VALUES
('00:00:00'),
('01:00:00'),
('02:00:00'),
('03:00:00'),
('04:00:00'),
('05:00:00'),
('06:00:00'),
('07:00:00'),
('08:00:00'),
('09:00:00'),
('10:00:00'),
('11:00:00'),
('12:00:00'),
('13:00:00'),
('14:00:00'),
('15:00:00'),
('16:00:00'),
('17:00:00'),
('18:00:00'),
('19:00:00'),
('20:00:00'),
('21:00:00'),
('22:00:00'),
('23:00:00');
然后,以下查询将提供所有预订客房的空房情况:
查询 1:
select r.id
, r.Name
, res_date + interval t.slot hour_second available
from Time_Slots t
join Rooms r
on t.Slot between r.available_from and r.available_to
join (select distinct room_id, date(start) res_date from Reservation) res
on res.room_id = r.id
where (r.id, res_date + interval t.slot hour_second) not in (
select r.room_id
, date(r.start) + interval t.slot hour_second Reserved
from Time_Slots t
join Reservation r
on r.start <= date(r.end) + interval t.slot hour_second
and date(r.start) + interval t.slot hour_second < r.end)
此查询的工作原理是,首先从Times_Slots
中为该会议室至少有一个预留选择可用时段,然后筛选出预留的时隙。
结果:
| id | Name | available |
|----|--------|----------------------|
| 1 | Single | 2019-01-03T09:00:00Z |
| 1 | Single | 2019-01-03T10:00:00Z |
| 1 | Single | 2019-01-03T11:00:00Z |
| 1 | Single | 2019-01-03T12:00:00Z |
| 1 | Single | 2019-01-03T13:00:00Z |
| 1 | Single | 2019-01-03T14:00:00Z |
| 1 | Single | 2019-01-03T17:00:00Z |
| 1 | Single | 2019-01-03T20:00:00Z |
| 1 | Single | 2019-01-03T21:00:00Z |
在您的示例输出中,您指示房间在 2019-01-03 22:00:00、2019-01-03 23:00:00、2019-01-03 24:00:00 可用,但是这些时间是在房间表定义的可用性块之后,所以我的查询排除了这些时间。
您遇到的第一个问题是您的架构设置很差。您没有良好的数据规范化。1) 重命名字段以提高清晰度。2) 将这两个表更改为如下所示:
Reservation:
Res_ID | hotel_id | room_id | res_start | res_end | status
Rooms:
Room_ID | hotel_id | room_name | room_number | available_from | available_to
您将需要一个定义了时间段的表。您可以使用 CTE 进行,然后将其与您的房间CROSS JOIN
。这是CROSS JOIN
有用的少数情况之一。
现在像这样执行查询:
WITH timeslots AS (
SELECT CURRENT_DATE() AS time_slot UNION
SELECT CURRENT_DATE() + 1/24 UNION
SELECT CURRENT_DATE() + 2/24 UNION
SELECT CURRENT_DATE() + 3/24 UNION
SELECT CURRENT_DATE() + 4/24 UNION
SELECT CURRENT_DATE() + 5/24 UNION
SELECT CURRENT_DATE() + 6/24 UNION
SELECT CURRENT_DATE() + 7/24 UNION
SELECT CURRENT_DATE() + 8/24 UNION
SELECT CURRENT_DATE() + 9/24 UNION
SELECT CURRENT_DATE() + 10/24 UNION
SELECT CURRENT_DATE() + 11/24 UNION
SELECT CURRENT_DATE() + 12/24 UNION
SELECT CURRENT_DATE() + 13/24 UNION
SELECT CURRENT_DATE() + 14/24 UNION
SELECT CURRENT_DATE() + 15/24 UNION
SELECT CURRENT_DATE() + 16/24 UNION
SELECT CURRENT_DATE() + 17/24 UNION
SELECT CURRENT_DATE() + 18/24 UNION
SELECT CURRENT_DATE() + 19/24 UNION
SELECT CURRENT_DATE() + 20/24 UNION
SELECT CURRENT_DATE() + 21/24 UNION
SELECT CURRENT_DATE() + 22/24 UNION
SELECT CURRENT_DATE() + 23/24 )
SELECT r.id, r.name, r.number, r.type, r.rating,
t.time_slot AS time_slot_open,
t.time_slot + 1/24 AS time_slot_close,
res.Res_ID
FROM rooms r
CROSS JOIN timeslots t
LEFT JOIN reservation res ON res.hotel_id = r.hotel_id AND res.room_id = r.room_id
AND time_slot_open >= res.res_start AND time_slot_open < res.res_close
这将为您提供所有酒店房间的列表,每个房间有 24 条记录。如果该房间有预订,则它将显示该时段的预订ID。从这里,您可以按原样使用数据,也可以进一步将其放入其自己的 CTE 中,然后从中选择预留 ID 为空的所有内容。您还可以根据该 ID 加入或查找有关预留的其他数据。
更新
如果您运行 8.0 之前的 MySQL 版本,则不支持WITH
子句(请参阅:如何在 MySQL 中使用"WITH"子句?您必须将其设置为如下所示的子查询:
SELECT r.id, r.name, r.number, r.type, r.rating,
t.time_slot AS time_slot_open,
t.time_slot + 1/24 AS time_slot_close,
res.Res_ID
FROM rooms r
CROSS JOIN (SELECT CURRENT_DATE() AS time_slot UNION
SELECT CURRENT_DATE() + 1/24 UNION
SELECT CURRENT_DATE() + 2/24 UNION
SELECT CURRENT_DATE() + 3/24 UNION
SELECT CURRENT_DATE() + 4/24 UNION
SELECT CURRENT_DATE() + 5/24 UNION
SELECT CURRENT_DATE() + 6/24 UNION
SELECT CURRENT_DATE() + 7/24 UNION
SELECT CURRENT_DATE() + 8/24 UNION
SELECT CURRENT_DATE() + 9/24 UNION
SELECT CURRENT_DATE() + 10/24 UNION
SELECT CURRENT_DATE() + 11/24 UNION
SELECT CURRENT_DATE() + 12/24 UNION
SELECT CURRENT_DATE() + 13/24 UNION
SELECT CURRENT_DATE() + 14/24 UNION
SELECT CURRENT_DATE() + 15/24 UNION
SELECT CURRENT_DATE() + 16/24 UNION
SELECT CURRENT_DATE() + 17/24 UNION
SELECT CURRENT_DATE() + 18/24 UNION
SELECT CURRENT_DATE() + 19/24 UNION
SELECT CURRENT_DATE() + 20/24 UNION
SELECT CURRENT_DATE() + 21/24 UNION
SELECT CURRENT_DATE() + 22/24 UNION
SELECT CURRENT_DATE() + 23/24 ) t
LEFT JOIN reservation res ON res.hotel_id = r.hotel_id AND res.room_id = r.room_id
AND time_slot_open >= res.res_start AND time_slot_open < res.res_close
计划 A(每小时一行)
- 摆脱 T 和 Z;MySQL不理解这种语法。
- 您的汽车旅馆位于一个时区,对吗? 然后使用
DATETIME
或TIMESTAMP
是等效的。 - 对于 3 小时的预订,请排 3 行。 (使用范围可能会更混乱。
- 唉,你使用的是MySQL,而不是MariaDB;后者有自动序列生成器。 示例:名为
seq_0_to_23
的伪表的作用类似于预填充了数字 0 到 23 的表。 - 查找可用时间需要有一个包含所有日期所有可能时间的表格,因此上面的注释。 要么
- 做算术,要么离开几个小时:
- 由于 LEFT 简单明了,
我将讨论它:
mysql> SELECT NOW(), LEFT(NOW(), 13);
+---------------------+-----------------+
| NOW() | LEFT(NOW(), 13) |
+---------------------+-----------------+
| 2019-01-03 13:43:56 | 2019-01-03 13 |
+---------------------+-----------------+
1 row in set (0.00 sec)
第二列显示一个字符串,可用于指示当天的下午 1 点。
计划B(范围)
另一种方法是使用范围。 但是,处理过程很复杂,因为所有时间始终与预订或"可用"相关联。 代码变得复杂,但性能很好:http://mysql.rjweb.org/doc.php/ipranges
计划 C(位)
该表包含一个日期(无时间),以及一个恰好是 24 位的MEDIUMINT UNSIGNED
。 每个位代表一天中的一个小时。
使用各种布尔运算:
|
(OR) 位在一起以查看分配的小时数。0xFFFFFF & ~hours
看看有什么可用的。BIT_COUNT()
计算位数(小时)。- 虽然可以在 SQL 中确定房间的可用时间,但最好在客户端代码中执行此操作。 我假设你有一个PHP/Java/任何前端!
- 等。
更多?
您想更详细地讨论其中任何一个吗?
您需要将房间表与时隙表(24 行)连接起来。这将生成给定房间的所有可能时间段的列表。过滤掉不可用的时隙是微不足道的:
SELECT rooms.id, rooms.name, TIMESTAMP(checkdates.checkdate, timeslots.timeslot) AS datetimeslot
FROM rooms
INNER JOIN (
SELECT CAST('00:00' AS TIME) AS timeslot UNION
SELECT CAST('01:00' AS TIME) UNION
SELECT CAST('02:00' AS TIME) UNION
SELECT CAST('03:00' AS TIME) UNION
SELECT CAST('04:00' AS TIME) UNION
SELECT CAST('05:00' AS TIME) UNION
SELECT CAST('06:00' AS TIME) UNION
SELECT CAST('07:00' AS TIME) UNION
SELECT CAST('08:00' AS TIME) UNION
SELECT CAST('09:00' AS TIME) UNION
SELECT CAST('10:00' AS TIME) UNION
SELECT CAST('11:00' AS TIME) UNION
SELECT CAST('12:00' AS TIME) UNION
SELECT CAST('13:00' AS TIME) UNION
SELECT CAST('14:00' AS TIME) UNION
SELECT CAST('15:00' AS TIME) UNION
SELECT CAST('16:00' AS TIME) UNION
SELECT CAST('17:00' AS TIME) UNION
SELECT CAST('18:00' AS TIME) UNION
SELECT CAST('19:00' AS TIME) UNION
SELECT CAST('20:00' AS TIME) UNION
SELECT CAST('21:00' AS TIME) UNION
SELECT CAST('22:00' AS TIME) UNION
SELECT CAST('23:00' AS TIME)
) AS timeslots ON timeslots.timeslot >= rooms.available_from
AND timeslots.timeslot < rooms.available_to
CROSS JOIN (
SELECT CAST('2019-01-03' AS DATE) AS checkdate
) AS checkdates
WHERE NOT EXISTS (
SELECT 1
FROM reservations
WHERE room_id = rooms.id
AND TIMESTAMP(checkdates.checkdate, timeslots.timeslot) >= `start`
AND TIMESTAMP(checkdates.checkdate, timeslots.timeslot) < `end`
)
DB小提琴上的演示
上述查询检查一个日期 (2019-01-03) 的可用性。对于多个日期,只需将它们添加到checkdates
.