mysql - 使用 mysql 查找日期间隔

Question

我想提取 bookingId 为空的记录，并获得最大未预订天数(从第一个免费日算起)。预期结果应该是:

id = 1, 2013-08-03, 7 days free
id = 1, 2013-08-24, 7 days free
id = 2, 2013-08-07, 10 days free
id = 2, 2013-08-24, 7 days free

最好的办法是，如果我还可以查询空闲时间段:例如查询 1、2、3、4、5、6、7..14.. 空闲天数。这是我的源数据的示例:

id      bookingDate    bookingId
--------------------------------
1        2013-08-03        0
1        2013-08-04        0
1        2013-08-05        0
1        2013-08-06        0
1        2013-08-07        0
1        2013-08-08        0
1        2013-08-09        0
1        2013-08-10        112
1        2013-08-11        112
1        2013-08-12        112
1        2013-08-13        112
1        2013-08-14        112
1        2013-08-15        112
1        2013-08-16        112
1        2013-08-17        112
1        2013-08-18        112
1        2013-08-19        112
1        2013-08-20        112
1        2013-08-21        112
1        2013-08-22        112
1        2013-08-23        112
1        2013-08-24        0
1        2013-08-25        0
1        2013-08-26        0
1        2013-08-27        0
1        2013-08-28        0
1        2013-08-29        0
1        2013-08-30        0
1        2013-08-31        0
2        2013-08-03        78
2        2013-08-04        78
2        2013-08-05        78
2        2013-08-06        78
2        2013-08-07        0
2        2013-08-08        0
2        2013-08-09        0
2        2013-08-10        0
2        2013-08-11        0
2        2013-08-12        0
2        2013-08-13        0
2        2013-08-14        0
2        2013-08-15        0
2        2013-08-16        0
2        2013-08-17        39
2        2013-08-18        39
2        2013-08-19        39
2        2013-08-20        39
2        2013-08-21        39
2        2013-08-22        39
2        2013-08-23        39
2        2013-08-24        0
2        2013-08-25        0
2        2013-08-26        0
2        2013-08-27        0
2        2013-08-28        0
2        2013-08-29        0
2        2013-08-30        0
2        2013-08-31        0

如果有人有更好的数据结构的好主意，我可以尝试实现。数据库仍在 build 中:-)

编辑:

CREATE TABLE IF NOT EXISTS `pricesBookings` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `baseId` int(11) NOT NULL,
  `bookingDate` date NOT NULL,
  `bookingId` int(11) NOT NULL,
  `price` decimal(10,2) NOT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `baseId` (`baseId`,`bookingDate`)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8;

Answer 1

这应该给出正确的结果:

select
  id,
  min(startDate) as startFreeDate,
  count(*) - (endDate is null) numFreeDays
from (
  select
    pb1.id,
    pb1.bookingDate startDate,
    min(pb2.bookingDate) endDate
  from
    pricesBookings pb1 left join pricesBookings pb2
    on pb1.id=pb2.id
       and pb2.price>0
       and pb2.bookingDate>pb1.bookingDate
  where
    pb1.price=0
  group by
    pb1.id,
    pb1.bookingDate
) s
group by id, endDate
order by id, startDate

查看here .

如果需要搜索所有空闲时段，比如14天，可以加上HAVING:

group by id, endDate
having count(*) - (endDate is null) >= 14
order by id, startDate