參考網(wǎng)址 https://www.jb51.net/article/29551.htm
復(fù)制代碼 代碼如下:
SELECT [StartDate] FROM [dbo].[udf_Week](2012,2012) WHERE [Week] = 1
上面SQL語句執(zhí)行結(jié)果:
但你還是覺得此方法很復(fù)雜,而且只需要日期部分,時(shí)間部分無需顯示。因此Insus.NET更改并產(chǎn)生如下一個(gè)新函數(shù),你把函數(shù)附加入你的數(shù)據(jù)庫中,即可在程序中應(yīng)用它了。
復(fù)制代碼 代碼如下:
udf_StartDateOfFirstWeek
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE FUNCTION udf_StartDateOfFirstWeek
(
@Year INT
)
RETURNS DATE
AS
BEGIN
DECLARE @StartDate DATE = CAST((CAST(@Year AS VARCHAR(4)) + '-01-01') AS DATE)
RETURN
CASE WHEN (DATEPART(DW,@StartDate) > 4)
THEN DATEADD(DAY,(8 - DATEPART(DW,@StartDate)) ,@StartDate)
ELSE DATEADD(DAY,(-(DATEPART(DW,@StartDate)-1)),@StartDate)
END
END
GO
函數(shù)執(zhí)行Demo: