ORACLE/MSSQL日期函数在报表项目中的应用【日报/周报/月报】

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

--3.一年的第一天
SELECT DATEADD(yy, DATEDIFF(yy,0,getdate()), 0)
SELECT DATEADD(yy, DATEDIFF(yy,0,getdate()), 0)

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

--5.当天的半夜
SELECT DATEADD(dd, DATEDIFF(dd,0,getdate()), 0)
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))
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))
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))
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))
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)
select DATEADD(wk, DATEDIFF(wk,0,dateadd(dd,6-datepart(day,getdate()),getdate())), 0)

--本周
select trunc(sysdate,'d')+1 from dual;
select trunc(sysdate,'d')+7 from dual;

--本月
select trunc(sysdate,'mm') from dual;
select last_day(trunc(sysdate)) from dual;

--本季
select trunc(sysdate,'Q') from dual;
select add_months(trunc(sysdate,'Q'),3)-1 from dual;

--本年
select trunc(sysdate,'yyyy') from dual;
select add_months(trunc(sysdate,'yyyy'),12)-1 from dual;

-- 星期一到星期六处理方式
select trunc(to_date('2011-10-16','yyyy-MM-dd'),'day')+8 from dual;

-- 如果是星期天处理方式
select trunc(to_date('2011-10-16','yyyy-MM-dd'),'day')+1 from dual;

-- 判断是星期几
select to_char(to_date('2011-12-26','yyyy-mm-dd'),'day') from dual;