SQL语句中的日期计算

SQL语句中的日期计算

1. 本月的第一天

SELECT DATEADD(mm, DATEDIFF(mm,0,getdate()), 0)

2. 本月的最后一天

SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(m,0,getdate())+1, 0))

3.上个月的第一天

select dateadd(m,-1, DATEADD(mm, DATEDIFF(mm,0,getdate()), 0))

4. 上个月的最后一天

SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(mm,0,getdate()), 0))

5. 本周的星期一

SELECT DATEADD(wk, DATEDIFF(wk,0,getdate()), 0)

6.本周的周日

select dateadd(d,+6 ,DATEADD(wk, DATEDIFF(wk,0,getdate()), 0) )

7.上周的星期一

select dateadd(d,-7 ,DATEADD(wk, DATEDIFF(wk,0,getdate()), 0) )

8.上周的周日

select dateadd(d,-1 ,DATEADD(wk, DATEDIFF(wk,0,getdate()), 0) )

9. 一年的第一天

SELECT DATEADD(yy, DATEDIFF(yy,0,getdate()), 0)

10. 季度的第一天

SELECT DATEADD(qq, DATEDIFF(qq,0,getdate()), 0)

11. 去年的最后一天

SELECT dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate()), 0))

12. 本月的第一个星期一

select DATEADD(wk, DATEDIFF(wk,0,dateadd(dd,6-datepart(day,getdate)),getdate))),0)

13. 本年的最后一天

SELECT dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate())+1, 0))。

Sql Server中的日期与时间函数

1. 当前系统日期、时间

select getdate()

2. dateadd 在向指定日期加上一段时间的基础上，返回新的 datetime 值

例如：向日期加上2天

select dateadd(day,2,'2004-10-15') --返回：2004-10-17 00:00:00.000

3. datediff 返回跨两个指定日期的日期和时间边界数。

select datediff(day,'2004-09-01','2004-09-18') --返回：17

4. datepart 返回代表指定日期的指定日期部分的整数。

SELECT DATEPART(month, '2004-10-15') --返回 10

5. datename 返回代表指定日期的指定日期部分的字符串

SELECT datename(weekday, '2004-10-15') --返回：星期五

6. day(), month(),year() --可以与datepart对照一下

select 当前日期=convert(varchar(10),getdate(),120)

,当前时间=convert(varchar(8),getdate(),114)

select datename(dw,'2004-10-15')

select 本年第多少周=datename(week,'2004-10-15')

,今天是周几=datename(weekday,'2004-10-15')
http://www.52186.cn/nibablog/blogview.asp?logID=333
sql日期格式转换

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来源：CSDN 发布会员：新书城收集整理 发布时间：2006-7-31 人气：384

在sql中，smalldatetime及datetime型的数据显示不是那么让人满意，因此我找了些格式化的方法列出来"

convert(char(10),datetime,101)

在数据库取出来的时候就转换好

select getdate()

2006-05-12 11:06:08.177

我整理了一下SQL Server里面可能经常会用到的日期格式转换方法:

举例如下:

select Convert(varchar(10),getdate(),120)

2006-05-12

select CONVERT(varchar, getdate(), 120 )

2006-05-12 11:06:08

select replace(replace(replace(CONVERT(varchar, getdate(), 120 ),'-',''),' ',''),':','')

20060512110608

select CONVERT(varchar(12) , getdate(), 111 )

2006/05/12

select CONVERT(varchar(12) , getdate(), 112 )

20060512

select CONVERT(varchar(12) , getdate(), 102 )

2006.05.12

其它几种不常用的日期格式转换方法:

select CONVERT(varchar(12) , getdate(), 101 )

0612/2005 select CONVERT(varchar(12) , getdate(), 103 )

12/09/2004

select CONVERT(varchar(12) , getdate(), 104 )

12.05.2006

select CONVERT(varchar(12) , getdate(), 105 )

12-05-2006

select CONVERT(varchar(12) , getdate(), 106 )

12 05 2006

select CONVERT(varchar(12) , getdate(), 107 )

05 12, 2006

select CONVERT(varchar(12) , getdate(), 108 )

11:06:08

select CONVERT(varchar(12) , getdate(), 109 )

0512 2006 1

select CONVERT(varchar(12) , getdate(), 110 )

09-12-2004

select CONVERT(varchar(12) , getdate(), 113 )

12 052006

select CONVERT(varchar(12) , getdate(), 114 )

11:06:08.177

============================================================================================

实例演练

select * from salesmb

select count(*) from salesdreport where employeeid='11'and productsid='7' and (updatetime between '2006-8-1 00:00:00'and '2006-8-30 00:00:00') --销售数量

select sum(sales) from salesmb where eid='11'and productsid='7' and (mbrq between '2006-8-1 00:00:00'and '2006-8-30 00:00:00') --目标数量

select dateadd(d,-day(getdate()),getdate())

select cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-1 00:00'

select cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-'+cast(day(getdate()) as varchar)

select dateadd(m,1,dateadd(d,-day(getdate()),getdate()))

select dateadd(m,1,getdate())

=====================================================================================================================================================

select * from salesmb

select count(*) from salesdreport where employeeid='11'and productsid='7' and (updatetime between '2006-8-1 00:00:00'and '2006-8-30 00:00:00') --销售数量

select sum(sales) from salesmb where eid='11'and productsid='7' and (mbrq between '2006-8-1 00:00:00'and '2006-8-30 00:00:00') --目标数量

select dateadd(d,-day(getdate()),getdate())

select cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-1 00:00'

select cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-'+cast(day(getdate()) as varchar)

select dateadd(m,1,dateadd(d,-day(getdate()),getdate()))

select dateadd(m,1,getdate())

======================================================================================================================================================

select * from salesmb

select count(*) from salesdreport where employeeid='11'and productsid='7' and (updatetime between '2006-8-1 00:00:00'and '2006-8-30 00:00:00') --销售数量

select sum(sales) from salesmb where eid='11'and productsid='7' and (mbrq between '2006-8-1 00:00:00'and '2006-8-30 00:00:00') --目标数量

select dateadd(d,-day(getdate()),getdate())

select cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-1 00:00'

select cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-'+cast(day(getdate()) as varchar)

select dateadd(m,1,dateadd(d,-day(getdate()),getdate()))

select dateadd(m,1,getdate())

===============================================================================================================================

select getdate()

select dateadd(d,1,dateadd(d,-day(getdate()),getdate()))+"00:00"

declare @sdate smalldatetime

select cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-1 00:00'

select @sdate

select dateadd(day,-1,dateadd(Month,1,@sdate))

select cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-1 00:00'

select dateadd(d,-day(getdate()),getdate())

select dateadd(day,-1,dateadd(Month,1,cast(year(getdate()) as nvarchar)+'-'+cast(month(getdate()) as varchar)+'-1 00:00'))

select dateadd(d,-day(getdate()),getdate())

select dateadd(d,1,dateadd(d,-day(getdate()),getdate()))

select dateadd(m,

SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(mm,0,getdate()), 0))

SELECT dateadd(ms,0,DATEADD(mm, DATEDIFF(mm,0,getdate()), 0))