Question

我想计算2月25/02/2019起的天数，预期结果是4

我尝试在SQL Server中使用master..spt_values，但没有得到预期的结果

declare @fdays int ,@d date=cast('20190201' as date),@JoinDate date=cast('20190225' as date)
select count(dateadd(dd,number,@d)) from master..spt_values
where type = 'p'
and month(dateadd(dd,number,@d))=month(@d)
and year(dateadd(dd,number,@d))=year(@d)    
and cast(GETDate() as date)>= Cast(dateadd(dd,number,@JoinDate) as date )

以上代码的结果是28，但我想要4

请帮助我找到预期的结果

Answer 1

这是简单的日期算术，您无需使用spt_values：

declare @d date = '20190225';

select datediff(month,0,@d) as MonthsDiff   -- Months since an arbitrary date
      ,dateadd(month,datediff(month,0,@d)+1,0) as StartOfFollowingMonth -- Add months above +1 to same arbitrary date
      ,datediff(day,@d,dateadd(month,datediff(month,0,@d)+1,0)) as DaysBetweenGivenDate -- DATEDIFF between given date and start of month from above;

输出：

+------------+-------------------------+----------------------+
| MonthsDiff |  StartOfFollowingMonth  | DaysBetweenGivenDate |
+------------+-------------------------+----------------------+
|       1429 | 2019-03-01 00:00:00.000 |                    4 |
+------------+-------------------------+----------------------+

Answer 2

尝试一下：

 declare @date date='20140603'
    select datediff(day, @date, dateadd(month, 1, @date))-day(@date)

Answer 3

从SQL Server 2012开始，您可以仅使用EOMONTH函数：

SELECT DATEDIFF(DAY, '20190225', EOMONTH ('20190225')) + 1 [thedays]

= 4。

如何获取给定日期的月份剩余天数

3 个答案: