Question

我对sql-server比较新;我试图从一个表单变量拉出一个开始日期和结束日期作为字符串，然后将其转换为datetime（yyyy-mm-dd）格式，我似乎无法找到任何有用的东西。尝试的代码和结果错误如下。任何建议将不胜感激。

declare @startdate as varchar
declare @enddate as varchar
set @startdate=cast(@startdate as datetime)
set @enddate=cast(@enddate as datetime)

SELECT order_date, inv_no 
from invoices 
where order_date between @startdate and @enddate

我不断得到的错误是：

从字符串转换日期时转换失败。

我该如何解决这个问题？

Answer 1

指定varchar的长度：

declare @startdate as varchar(10)
declare @enddate as varchar(10)
set @startdate=cast(@startdate as datetime)
set @enddate=cast(@enddate as datetime)

SELECT order_date, inv_no 
from invoices 
where order_date between @startdate and @enddate

Answer 2

你不必必须施展

declare @startdate varchar(50)
declare @enddate varchar(50)
declare @start datetime = @startdate, @end datetime = @enddate
select @start, @end

如何在sql-server中将字符串变量转换为datetime变量？

2 个答案: