从SQL Server中的周数获取周开始日期和周结束日期

Question

我有一个查询计算会员在数据库中的结婚日期...

Select 
  Sum(NumberOfBrides) As [Wedding Count], 
  DATEPART( wk, WeddingDate) as [Week Number],
  DATEPART( year, WeddingDate) as [Year]
FROM  MemberWeddingDates
Group By DATEPART( year, WeddingDate), DATEPART( wk, WeddingDate)
Order By Sum(NumberOfBrides) Desc

如何在结果集中表示每周的开始和结束时计算出来？

Select 
      Sum(NumberOfBrides) As [Wedding Count], 
      DATEPART( wk, WeddingDate) as [Week Number],
      DATEPART( year, WeddingDate) as [Year],
      ??? as WeekStart,
      ??? as WeekEnd

    FROM  MemberWeddingDates
    Group By DATEPART( year, WeddingDate), DATEPART( wk, WeddingDate)
    Order By Sum(NumberOfBrides) Desc

Answer 1

您可以找到星期几,并在几天内添加日期以获取开始日期和结束日期.

DATEADD(dd, -(DATEPART(dw, WeddingDate)-1), WeddingDate) [WeekStart]

DATEADD(dd, 7-(DATEPART(dw, WeddingDate)), WeddingDate) [WeekEnd]

你可能也想看看从日期开始的时间.

Answer 2

这是一个DATEFIRST不可知的解决方案:

SET DATEFIRST 4     /* or use any other weird value to test it */
DECLARE @d DATETIME

SET @d = GETDATE()

SELECT
  @d ThatDate,
  DATEADD(dd, 0 - (@@DATEFIRST + 5 + DATEPART(dw, @d)) % 7, @d) Monday,
  DATEADD(dd, 6 - (@@DATEFIRST + 5 + DATEPART(dw, @d)) % 7, @d) Sunday

Answer 3

你也可以用这个:

  SELECT DATEADD(day, DATEDIFF(day, 0, WeddingDate) /7*7, 0) AS weekstart,
         DATEADD(day, DATEDIFF(day, 6, WeddingDate-1) /7*7 + 7, 6) AS WeekEnd