--本周: select dateadd(d,number,'2011-01-01') from master..spt_values where type='p' and number<365 and datepart(wk,dateadd(d,number,'2011-01-01'))=datepart(wk,getdate()) /* ----------------------- 2011-10-16 00:00:00.000 2011-10-17 00:00:00.000 2011-10-18 00:00:00.000 2011-10-19 00:00:00.000 2011-10-20 00:00:00.000 2011-10-21 00:00:00.000 2011-10-22 00:00:00.000(7 行受影响)*/
DECLARE @year nvarchar(4),@week INT SElecT @year=2011,@week=43 ;WITH a AS ( SELECT CAST(@year+'0101' AS DATETIME) AS dt UNION ALL SELECT dt+1 FROM a WHERE YEAR(dt+1)<@year+1 ) SELECT * FROM a WHERE DATEPART(wk,DATEADD(Day,1-(DATEPART(Weekday,dt)+@@DATEFIRST-2)%7-1,dt))=@week OPTION(MAXRECURSION 0) /* 2011-10-17 00:00:00.000 2011-10-18 00:00:00.000 2011-10-19 00:00:00.000 2011-10-20 00:00:00.000 2011-10-21 00:00:00.000 2011-10-22 00:00:00.000 2011-10-23 00:00:00.000 */
select dateadd(d,number,'2011-01-01')
from master..spt_values
where type='p' and number<365
and datepart(wk,dateadd(d,number,'2011-01-01'))=datepart(wk,getdate())
/*
-----------------------
2011-10-16 00:00:00.000
2011-10-17 00:00:00.000
2011-10-18 00:00:00.000
2011-10-19 00:00:00.000
2011-10-20 00:00:00.000
2011-10-21 00:00:00.000
2011-10-22 00:00:00.000(7 行受影响)*/
SElecT @year=2011,@week=43
;WITH a
AS
(
SELECT CAST(@year+'0101' AS DATETIME) AS dt
UNION ALL
SELECT dt+1 FROM a WHERE YEAR(dt+1)<@year+1
)
SELECT *
FROM a
WHERE DATEPART(wk,DATEADD(Day,1-(DATEPART(Weekday,dt)+@@DATEFIRST-2)%7-1,dt))=@week
OPTION(MAXRECURSION 0)
/*
2011-10-17 00:00:00.000
2011-10-18 00:00:00.000
2011-10-19 00:00:00.000
2011-10-20 00:00:00.000
2011-10-21 00:00:00.000
2011-10-22 00:00:00.000
2011-10-23 00:00:00.000
*/
SET @dt=GETDATE()DECLARE @number int
SET @number=3--1.指定日期该年的第一天或最后一天
--A. 年的第一天
SELECT CONVERT(char(5),@dt,120)+'1-1'--B. 年的最后一天
SELECT CONVERT(char(5),@dt,120)+'12-31'
--2.指定日期所在季度的第一天或最后一天
--A. 季度的第一天
SELECT CONVERT(datetime,
CONVERT(char(8),
DATEADD(Month,
DATEPART(Quarter,@dt)*3-Month(@dt)-2,
@dt),
120)+'1')--B. 季度的最后一天(CASE判断法)
SELECT CONVERT(datetime,
CONVERT(char(8),
DATEADD(Month,
DATEPART(Quarter,@dt)*3-Month(@dt),
@dt),
120)
+CASE WHEN DATEPART(Quarter,@dt) in(1,4)
THEN '31'ELSE '30' END)--C. 季度的最后一天(直接推算法)
SELECT DATEADD(Day,-1,
CONVERT(char(8),
DATEADD(Month,
1+DATEPART(Quarter,@dt)*3-Month(@dt),
@dt),
120)+'1')
--3.指定日期所在月份的第一天或最后一天
--A. 月的第一天
SELECT CONVERT(datetime,CONVERT(char(8),@dt,120)+'1')--B. 月的最后一天
SELECT DATEADD(Day,-1,CONVERT(char(8),DATEADD(Month,1,@dt),120)+'1')--C. 月的最后一天(容易使用的错误方法)
SELECT DATEADD(Month,1,DATEADD(Day,-DAY(@dt),@dt))
--4.指定日期所在周的任意一天
SELECT DATEADD(Day,@number-DATEPART(Weekday,@dt),@dt)
--5.指定日期所在周的任意星期几
--A. 星期天做为一周的第1天
SELECT DATEADD(Day,@number-(DATEPART(Weekday,@dt)+@@DATEFIRST-1)%7,@dt)--B. 星期一做为一周的第1天
SELECT DATEADD(Day,@number-(DATEPART(Weekday,@dt)+@@DATEFIRST-2)%7-1,@dt)