SQL 查询本周本月问题

sql 查询本周本月问题 ---求相差天数 select datediff(day,

sql 查询本周本月问题

---求相差天数
select datediff(day,'2004-01-01',getdate())

--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)

--查询本周注册人数
select count(*) from [user]
where datediff(week,create_day-1,getdate())=0

--上周注册人数
select count(*) from [user]
where datediff(week,create_day-1,getdate())=1


--本月注册人数
select count(*) from [user]
where datediff(month,create_day,getdate())=0

--上月注册人数
select count(*) from [user]
where datediff(month,create_day,getdate())=1

--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
--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

--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
--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
--本周
select count(*) from User
where datediff(dd,create_day,getdate())
--上周
select count(*) from User
where datediff(dd,create_day,(getdate() - datepart(dw,getdate())))
--本月
select count(*) from User
where datepart(mm,create_day) = datepart(mm,getdate())

--上月
select count(*) from User
where datepart(mm,create_day) = datepart(mm,getdate()) - 1

--本周
select count(*) from [User]
where datediff(dd,create_day,getdate())
--上周
select count(*) from [User]
where datediff(dd,create_day,(getdate() - datepart(dw,getdate())))
--本月
select count(*) from [User]
where datepart(mm,create_day) = datepart(mm,getdate())
--上月
select count(*) from [User]
where datepart(mm,create_day) = datepart(mm,getdate()) - 1
学习
month(create_day)=month(getdate())本月
month(create_day)=month(getdate())-1 上月

补充 查询今日所有的
SELECT * from feedback WHERE (DATEDIFF(d,fedtime,GETDATE())=0) ORDER BY fedid DESC

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