我有以下临时表，用于列出酒店的当前房间状态
declare @CurrentDate datetime = '2016-04-21'
select Lodging, Room, FirstName, LastName, TempStatus, @CurrentDate as CurrentDate
from RoomAvailability
这是以下结果：
Lodging Room FirstName LastName TempStatus CurrentDate
-------------------------------------------------------------------------------
marriok 119 Super Man Next guest 2016-03-24 00:00:00.000
marriok 101 Bat Man Next guest 2016-03-24 00:00:00.000
marriok 123 Aqua Man Leaving today 2016-03-24 00:00:00.000
marriok 103 Wonder Woman Leaving today 2016-03-24 00:00:00.000
marriok 101 Lex Luthor Leaving today 2016-03-24 00:00:00.000
这是我的预期结果：
Lodging Room CurrFirstName CurrLastName TempStatus CurrentDate NextFistName NextLastName TempStatus
----------------------------------------------------------------------------------------------------------------------------------------------
marriok 119 Super Man Next guest 2016-03-24 00:00:00.000 NULL NULL NULL
marriok 123 Aqua Man Leaving today 2016-03-24 00:00:00.000 NULL NULL NULL
marriok 103 Wonder Woman Leaving today 2016-03-24 00:00:00.000 NULL NULL NULL
marriok 101 Lex Luthor Leaving today 2016-03-24 00:00:00.000 Bat Man Next guest
我试过了：
declare @CurrentDate datetime = '2016-04-21'
select coalesce(a.Lodging, b.Lodging) as Lodging,
coalesce(a.Room, b.Room) as Room,
a.FirstName as CurrFirstName, a.LastName as CurrLastName, a.TempStatus, @CurrentDate,
b.NextFirstName, b.NextLastName, b.TempStatus
from RoomAvailability a
full join RoomAvailability b
on a.Lodging = b.Lodging
and a.Room = b.Room
我得到了这个：
Lodging Room CurrFirstName CurrLastName TempStatus CurrentDate NextFistName NextLastName TempStatus
----------------------------------------------------------------------------------------------------------------------------------------------
marriok 119 Super Man Next guest 2016-03-24 00:00:00.000 Super Man Next guest
marriok 101 Bat Man Next guest 2016-03-24 00:00:00.000 Bat Man Next guest
marriok 101 Bat Man Next guest 2016-03-24 00:00:00.000 Lex Luthor Leaving today
marriok 123 Aqua Man Leaving today 2016-03-24 00:00:00.000 Aqua Man Leaving today
marriok 103 Wonder Woman Leaving today 2016-03-24 00:00:00.000 Wonder Woman Leaving today
marriok 101 Lex Luthor Leaving today 2016-03-24 00:00:00.000 Bat Man Next guest
marriok 101 Lex Luthor Leaving today 2016-03-24 00:00:00.000 Lex Luthor Leaving today
那么我怎样才能获得独特或合并的行并列出在同一天离开并到达同一房间的人？ （没有CTE优先）
更新
临时表RoomAvailability是带有union all
的3个select语句的乘积3个select语句是相同的，它们只是在where子句中有所不同。在这3个select语句中包含一个签入和签出日期时间列。
我的第一个选择按照登记和退房日期（不包括）之间的当前日期变量进行过滤。我添加了一个列为“内部”的列。
我的第二个选择按当前日期变量等于办理登机手续进行过滤，我添加了状态文字“下一位客人”
最后一个选择按当前日期变量等于结账，我添加了状态'今天离开'。
更新2
如果没有CTE，这离我更近了
select coalesce(a.Lodging, b.Lodging),
coalesce(a.Room, b.Room),
a.FirstName, a.LastName, a.TempStatus,
b.FirstName, b.LastName, b.TempStatus,
@CurrentDate
from RoomAvailability a
left join RoomAvailability b
on a.Lodging = b.Lodging
and a.Room = b.Room
and a.TempStatus != b.TempStatus
但它在最后重复同一个房间的行
marriok 119 Super Man Next guest NULL NULL NULL 2016-04-21
marriok 101 Bat Man Next guest Lex Luthor Leaving today 2016-04-21
marriok 123 Aqua Man Leaving today NULL NULL NULL 2016-04-21
marriok 103 Wonder Woman Leaving today NULL NULL NULL 2016-04-21
marriok 101 Lex Luthor Leaving today Bat Max Next guest 2016-04-21 --<-- this should not be displayed
答案 0 :(得分：1)
如果您使用的是SQL 2012及更高版本，则最终查询会更简单。
假设您的数据位于名为#t
的表中设置数据
create table #t (
Lodging varchar(10)
, Room int
, FirstName varchar(10)
, LastName varchar(10)
, TempStatus varchar(20)
, CurrentDate datetime
)
insert into #t values
('marriok' ,119 ,'Super' ,'Man' ,'Next guest' ,'2016-03-24'),
('marriok' ,101 ,'Bat' ,'Man' ,'Next guest' ,'2016-03-24'),
('marriok' ,123 ,'Aqua' ,'Man' ,'Leaving today' ,'2016-03-24'),
('marriok' ,103 ,'Wonder' ,'Woman' ,'Leaving today' ,'2016-03-24'),
('marriok' ,101 ,'Lex' ,'Luthor' ,'Leaving today' ,'2016-03-24')
您的查询将是
with sortIt as (
select *, case TempStatus
when 'Next guest' then 2
when 'Leaving today' then 1
end as Sort
from #t
)
, addFld as (
select t1.*, t2.FirstName as NextFirstName, t2.LastName as NextLastName
, t2.TempStatus as NextTempStatus
from sortIt t1
left join sortIt t2 on t2.Room = t1.Room and t2.Sort = t1.Sort + 1
)
, removDup as (
select *, ROW_NUMBER() over (partition by Room order by NextFirstName desc) rn
from addFld
)
select * from removDup
where rn = 1
结果
+---------+------+-----------+----------+---------------+-------------------------+------+---------------+--------------+----------------+----+
| Lodging | Room | FirstName | LastName | TempStatus | CurrentDate | Sort | NextFirstName | NextLastName | NextTempStatus | rn |
+---------+------+-----------+----------+---------------+-------------------------+------+---------------+--------------+----------------+----+
| marriok | 101 | Lex | Luthor | Leaving today | 2016-03-24 00:00:00.000 | 1 | Bat | Man | Next guest | 1 |
| marriok | 103 | Wonder | Woman | Leaving today | 2016-03-24 00:00:00.000 | 1 | NULL | NULL | NULL | 1 |
| marriok | 119 | Super | Man | Next guest | 2016-03-24 00:00:00.000 | 2 | NULL | NULL | NULL | 1 |
| marriok | 123 | Aqua | Man | Leaving today | 2016-03-24 00:00:00.000 | 1 | NULL | NULL | NULL | 1 |
+---------+------+-----------+----------+---------------+-------------------------+------+---------------+--------------+----------------+----+