獲取SQL Server 2005/2008中的星期幾

若是我有一個日期01/01/2009，我想知道它是什麼日子，例如週一，週二等...

SQL Server 2005/2008中是否有內置函數？ 或者我須要使用輔助表嗎？

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#1樓

使用DATENAME或DATEPART ：

SELECT DATENAME(dw,GETDATE()) -- Friday
SELECT DATEPART(dw,GETDATE()) -- 6

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#2樓

儘管SQLMenace的答案已被接受，但您應該注意一個重要的SET選項

SET DATEFIRST

DATENAME將返回正確的日期名稱，但若是已更改星期的第一天，則返回相同的DATEPART值，以下圖所示。

declare @DefaultDateFirst int
set @DefaultDateFirst = @@datefirst
--; 7 First day of week is "Sunday" by default
select  [@DefaultDateFirst] = @DefaultDateFirst 

set datefirst @DefaultDateFirst
select datename(dw,getdate()) -- Saturday
select datepart(dw,getdate()) -- 7

--; Set the first day of week to * TUESDAY * 
--; (some people start their week on Tuesdays...)
set datefirst 2
select datename(dw,getdate()) -- Saturday
--; Returns 5 because Saturday is the 5th day since Tuesday.
--; Tue 1, Wed 2, Th 3, Fri 4, Sat 5
select datepart(dw,getdate()) -- 5 <-- It's not 7!
set datefirst @DefaultDateFirst

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#3樓

這是個人代碼的工做副本檢查它，如何在sql中從日期中檢索日期名稱

CREATE Procedure [dbo].[proc_GetProjectDeploymentTimeSheetData] 
@FromDate date,
@ToDate date

As 
Begin
select p.ProjectName + ' ( ' + st.Time +' '+'-'+' '+et.Time +' )' as ProjectDeatils,
datename(dw,pts.StartDate) as 'Day'
from 
ProjectTimeSheet pts 
join Projects p on pts.ProjectID=p.ID 
join Timing st on pts.StartTimingId=st.Id
join Timing et on pts.EndTimingId=et.Id
where pts.StartDate >= @FromDate
and pts.StartDate <= @ToDate
END

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#4樓

您可能會發現此版本頗有用。

-- Test DATA
select @@datefirst
create table #test (datum datetime)
insert #test values ('2013-01-01')
insert #test values ('2013-01-02')
insert #test values ('2013-01-03')
insert #test values ('2013-01-04')
insert #test values ('2013-01-05')
insert #test values ('2013-01-06')
insert #test values ('2013-01-07')
insert #test values ('2013-01-08')
-- Test DATA

select  Substring('Sun,Mon,Tue,Wed,Thu,Fri,Sat,Sun,Mon,Tue,Wed,Thu,Fri,Sat',
        (DATEPART(WEEKDAY,datum)+@@datefirst-1)*4+1,3),Datum
        from #test

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#5樓

歐洲：

declare @d datetime;
set @d=getdate();
set @dow=((datepart(dw,@d) + @@DATEFIRST-2) % 7+1);