TSQL 插入额外的行

Question

对于以下问题，识别和插入行的最有效方法是什么？

这是我的示例数据

vId StartDate   EndDate     Distance
------------------------------------    
256 2015-03-04  2015-03-05  365
271 2015-03-04  2015-03-04  86
315 2015-03-05  2015-03-06  254
256 2015-03-07  2015-03-09  150
458 2015-03-10  2015-03-12  141
458 2015-03-15  2015-03-17  85
315 2015-03-15  2015-03-16  76

我想为每个 vId 添加额外的行，其中 StartDate <> EndDate 如下所示，而不只是

315 2015-03-05  2015-03-06  254
256 2015-03-07  2015-03-09  150

我要展示以下内容

315 2015-03-05  2015-03-06  254
315 2015-03-06  2015-03-06  0

256 2015-03-07  2015-03-09  150
256 2015-03-08  2015-03-09  0
256 2015-03-09  2015-03-09  0

提前致谢。

Answer 1

只是一个简单的插入：

Insert Into Table(vId, StartDate, EndDate, Distance)
Select vId, DateAdd(dd, 1, StartDate), EndDate, 0
From TableName
Where StartDate <> EndDate

如果您只想 select 而不是插入，那么：

Select vId, StartDate, EndDate, Distance
From TableName

Union All

Select vId, DateAdd(dd, 1, StartDate), EndDate, 0
From TableName
Where StartDate <> EndDate

编辑

这假设最大差异为 100 天。如果你有更长的间隔，你可以添加更多的交叉连接来增加可能的值：

declare @t table(vId int, StartDate date, EndDate date, Distance int)

insert into @t values
(315, '2015-03-05',  '2015-03-06',  254),
(256, '2015-03-07',  '2015-03-09',  150)


;with cte as(select row_number() over(order by (select 1)) as rn
             from (values(1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) t1(n)
             cross join (values(1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) t2(n)
            )

select * from @t
union all
select t1.vId, ca.StartDate, t1.EndDate, 0 
from @t t1
cross apply(select dateadd(dd, c.rn, StartDate) as StartDate 
            from cte c 
            where dateadd(dd, c.rn, t1.StartDate) <= t1.EndDate) as ca
where t1.StartDate <> t1.EndDate
order by vId, StartDate

见fiddlehttp://sqlfiddle.com/#!6/9eecb/4641

TSQL 插入额外的行

TSQL Insert additional rows

tsql

sql-server-2008-r2