常用的获取时间差的sql语句

"select count(*) from [注册] where datediff(day,time,getdate())<1";//获取当天注册人员数 sql="select id,classid,classname,xiaoshoue,xiaoshou,jinhuo,kucun,addtime " sql=sql&" from xiaoshou where addtime between '" & format(starttime,"yyyy-mm-dd") & "' and '" & format(endtime,"yyyy-mm-dd") & "'" sql=sql&" order by id desc"

Select Fylb,Pm,Gg,Dw,Dj,Sl,Je FROM cqyzypzx where zxdate between {^2003-7-1}and {^2003-8-1}

近两个星期 sql="select * from table where datediff(week,riqi,getdate())<=2"

近三个月 sql="select * from table where datediff(month,riqi,getdate())<=3"

近一年 sql="select * from table where datediff(year,riqi,getdate())<=1"

Apply_Date between #"& startdate &" 23:59:59# and #"& enddate &" 23:59:59#"

--1.一个月第一天的 SELECT DATEADD(mm, DATEDIFF(mm,0,getdate()), 0)

--2.本周的星期一 SELECT DATEADD(wk, DATEDIFF(wk,0,getdate()), 0)

select dateadd(wk,datediff(wk,0,getdate()),6) --3.一年的第一天 SELECT DATEADD(yy, DATEDIFF(yy,0,getdate()), 0)

--4.季度的第一天 SELECT DATEADD(qq, DATEDIFF(qq,0,getdate()), 0)

--5.当天的半夜 SELECT DATEADD(dd, DATEDIFF(dd,0,getdate()), 0)

--6.上个月的最后一天 SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(mm,0,getdate()), 0))

--7.去年的最后一天 SELECT dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate()), 0))

--8.本月的最后一天 SELECT dateadd(ms,-3,DATEADD(mm, DATEDIFF(m,0,getdate())+1, 0))

--9.本年的最后一天 SELECT dateadd(ms,-3,DATEADD(yy, DATEDIFF(yy,0,getdate())+1, 0))

--10.本月的第一个星期一 select DATEADD(wk, DATEDIFF(wk,0,dateadd(dd,6-datepart(day,getdate()),getdate())), 0)

--如果要效率,这样写查询

--查询本周注册人数 select count(*) from [user] where create_day>=dateadd(day,2-datepart(weekday,getdate()),convert(varchar,getdate(),112))  and create_day<dateadd(day,9-datepart(weekday,getdate()),convert(varchar,getdate(),112))

--上周注册人数 select count(*) from [user] where create_day>=dateadd(day,-5-datepart(weekday,getdate()),convert(varchar,getdate(),112))  and create_day<dateadd(day,2-datepart(weekday,getdate()),convert(varchar,getdate(),112))

--本月注册人数 select count(*) from [user] where create_day>=dateadd(day,1-day(getdate()),convert(varchar,getdate(),112))  and create_day<dateadd(month,1,dateadd(day,1-day(getdate()),convert(varchar,getdate(),112)))

--上月注册人数 select count(*) from [user] where create_day>=dateadd(month,-1,dateadd(day,1-day(getdate()),convert(varchar,getdate(),112)))  and create_day<dateadd(day,1-day(getdate()),convert(varchar,getdate(),112))