客户编号 业务日期 上日余额
0001 2008-01-01 50
0001 2008-01-02 100
0002 2008-01-02 100
0002 2008-02-01 50
0003 2008-01-02 100
0004 2008-01-05 100
0004 2008-01-07 50
0004 2008-02-01 100按月份求出每客户编号每个客户的1月份的第一天(不一定是1号)的上日余额
结果:
客户编号 业务日期 上日余额
0001 2008-01-01 50
0002 2008-01-02 100
0003 2008-01-02 100
0004 2008-01-05 100
select a.客户编号,a.业务日期,a.上日余额 from table as a inner join
(select 客户编号,min(业务日期) as 业务日期 from table as b where month(业务日期) = 1 group by 客户编号) as b
on a.客户编号=b.客户编号 and a.业务日期 = b.业务日期
where a.业务日期 = 1
尝试了,用自连接可以实现,但觉得比较麻烦,请问大家还有其他好的方法吗?
或者有更方便的使用自连接的方法,请赐教,谢谢!
0001 2008-01-01 50
0001 2008-01-02 100
0002 2008-01-02 100
0002 2008-02-01 50
0003 2008-01-02 100
0004 2008-01-05 100
0004 2008-01-07 50
0004 2008-02-01 100按月份求出每客户编号每个客户的1月份的第一天(不一定是1号)的上日余额
结果:
客户编号 业务日期 上日余额
0001 2008-01-01 50
0002 2008-01-02 100
0003 2008-01-02 100
0004 2008-01-05 100
select a.客户编号,a.业务日期,a.上日余额 from table as a inner join
(select 客户编号,min(业务日期) as 业务日期 from table as b where month(业务日期) = 1 group by 客户编号) as b
on a.客户编号=b.客户编号 and a.业务日期 = b.业务日期
where a.业务日期 = 1
尝试了,用自连接可以实现,但觉得比较麻烦,请问大家还有其他好的方法吗?
或者有更方便的使用自连接的方法,请赐教,谢谢!
where not exists(select 1 from tb where userid=a.userid and datediff(mm,a.theDate,theDate)=0 and datediff(dd,a.theDate,theDate)>0)select a.* from tb a
inner join
(select convert(varchar(6),theDate,112) yyyyMM,MIN(theDate) mt,userID FROM tb GROUP BY convert(varchar(6),theDate,112),userID) b
ON mt=a.theDate and b.userID=a.userID
写法太多,不一一写了.按照 userid和convert(varchar(6),theDate,112) 做分组条件就是了.参见:同组中选一条.http://topic.csdn.net/u/20080123/18/9731d130-0d4b-4c11-8d89-f2c3ca331f0c.html
(爱新觉罗.毓华 2007-10-23于浙江杭州)
/*
数据如下:
name val memo
a 2 a2(a的第二个值)
a 1 a1--a的第一个值
a 3 a3:a的第三个值
b 1 b1--b的第一个值
b 3 b3:b的第三个值
b 2 b2b2b2b2
b 4 b4b4
b 5 b5b5b5b5b5
*/
--创建表并插入数据:
create table tb(name varchar(10),val int,memo varchar(20))
insert into tb values('a', 2, 'a2(a的第二个值)')
insert into tb values('a', 1, 'a1--a的第一个值')
insert into tb values('a', 3, 'a3:a的第三个值')
insert into tb values('b', 1, 'b1--b的第一个值')
insert into tb values('b', 3, 'b3:b的第三个值')
insert into tb values('b', 2, 'b2b2b2b2')
insert into tb values('b', 4, 'b4b4')
insert into tb values('b', 5, 'b5b5b5b5b5')
go--一、按name分组取val最大的值所在行的数据。
--方法1:
select a.* from tb a where val = (select max(val) from tb where name = a.name) order by a.name
--方法2:
select a.* from tb a where not exists(select 1 from tb where name = a.name and val > a.val)
--方法3:
select a.* from tb a,(select name,max(val) val from tb group by name) b where a.name = b.name and a.val = b.val order by a.name
--方法4:
select a.* from tb a inner join (select name , max(val) val from tb group by name) b on a.name = b.name and a.val = b.val order by a.name
--方法5
select a.* from tb a where 1 > (select count(*) from tb where name = a.name and val > a.val ) order by a.name
/*
name val memo
---------- ----------- --------------------
a 3 a3:a的第三个值
b 5 b5b5b5b5b5
*/--二、按name分组取val最小的值所在行的数据。
--方法1:
select a.* from tb a where val = (select min(val) from tb where name = a.name) order by a.name
--方法2:
select a.* from tb a where not exists(select 1 from tb where name = a.name and val < a.val)
--方法3:
select a.* from tb a,(select name,min(val) val from tb group by name) b where a.name = b.name and a.val = b.val order by a.name
--方法4:
select a.* from tb a inner join (select name , min(val) val from tb group by name) b on a.name = b.name and a.val = b.val order by a.name
--方法5
select a.* from tb a where 1 > (select count(*) from tb where name = a.name and val < a.val) order by a.name
/*
name val memo
---------- ----------- --------------------
a 1 a1--a的第一个值
b 1 b1--b的第一个值
*/--三、按name分组取第一次出现的行所在的数据。
select a.* from tb a where val = (select top 1 val from tb where name = a.name) order by a.name
/*
name val memo
---------- ----------- --------------------
a 2 a2(a的第二个值)
b 1 b1--b的第一个值
*/--四、按name分组随机取一条数据。
select a.* from tb a where val = (select top 1 val from tb where name = a.name order by newid()) order by a.name
/*
name val memo
---------- ----------- --------------------
a 1 a1--a的第一个值
b 5 b5b5b5b5b5
*/--五、按name分组取最小的两个(N个)val
select a.* from tb a where 2 > (select count(*) from tb where name = a.name and val < a.val ) order by a.name,a.val
select a.* from tb a where val in (select top 2 val from tb where name=a.name order by val) order by a.name,a.val
select a.* from tb a where exists (select count(*) from tb where name = a.name and val < a.val having Count(*) < 2) order by a.name
/*
name val memo
---------- ----------- --------------------
a 1 a1--a的第一个值
a 2 a2(a的第二个值)
b 1 b1--b的第一个值
b 2 b2b2b2b2
*/--六、按name分组取最大的两个(N个)val
select a.* from tb a where 2 > (select count(*) from tb where name = a.name and val > a.val ) order by a.name,a.val
select a.* from tb a where val in (select top 2 val from tb where name=a.name order by val desc) order by a.name,a.val
select a.* from tb a where exists (select count(*) from tb where name = a.name and val > a.val having Count(*) < 2) order by a.name
/*
name val memo
---------- ----------- --------------------
a 2 a2(a的第二个值)
a 3 a3:a的第三个值
b 4 b4b4
b 5 b5b5b5b5b5
*/
--七,如果整行数据有重复,所有的列都相同。
/*
数据如下:
name val memo
a 2 a2(a的第二个值)
a 1 a1--a的第一个值
a 1 a1--a的第一个值
a 3 a3:a的第三个值
a 3 a3:a的第三个值
b 1 b1--b的第一个值
b 3 b3:b的第三个值
b 2 b2b2b2b2
b 4 b4b4
b 5 b5b5b5b5b5
*/
--在sql server 2000中只能用一个临时表来解决,生成一个自增列,先对val取最大或最小,然后再通过自增列来取数据。
--创建表并插入数据:
create table tb(name varchar(10),val int,memo varchar(20))
insert into tb values('a', 2, 'a2(a的第二个值)')
insert into tb values('a', 1, 'a1--a的第一个值')
insert into tb values('a', 1, 'a1--a的第一个值')
insert into tb values('a', 3, 'a3:a的第三个值')
insert into tb values('a', 3, 'a3:a的第三个值')
insert into tb values('b', 1, 'b1--b的第一个值')
insert into tb values('b', 3, 'b3:b的第三个值')
insert into tb values('b', 2, 'b2b2b2b2')
insert into tb values('b', 4, 'b4b4')
insert into tb values('b', 5, 'b5b5b5b5b5')
goselect * , px = identity(int,1,1) into tmp from tbselect m.name,m.val,m.memo from
(
select t.* from tmp t where val = (select min(val) from tmp where name = t.name)
) m where px = (select min(px) from
(
select t.* from tmp t where val = (select min(val) from tmp where name = t.name)
) n where n.name = m.name)drop table tb,tmp/*
name val memo
---------- ----------- --------------------
a 1 a1--a的第一个值
b 1 b1--b的第一个值(2 行受影响)
*/
--在sql server 2005中可以使用row_number函数,不需要使用临时表。
--创建表并插入数据:
create table tb(name varchar(10),val int,memo varchar(20))
insert into tb values('a', 2, 'a2(a的第二个值)')
insert into tb values('a', 1, 'a1--a的第一个值')
insert into tb values('a', 1, 'a1--a的第一个值')
insert into tb values('a', 3, 'a3:a的第三个值')
insert into tb values('a', 3, 'a3:a的第三个值')
insert into tb values('b', 1, 'b1--b的第一个值')
insert into tb values('b', 3, 'b3:b的第三个值')
insert into tb values('b', 2, 'b2b2b2b2')
insert into tb values('b', 4, 'b4b4')
insert into tb values('b', 5, 'b5b5b5b5b5')
goselect m.name,m.val,m.memo from
(
select * , px = row_number() over(order by name , val) from tb
) m where px = (select min(px) from
(
select * , px = row_number() over(order by name , val) from tb
) n where n.name = m.name)drop table tb/*
name val memo
---------- ----------- --------------------
a 1 a1--a的第一个值
b 1 b1--b的第一个值(2 行受影响)
*/
insert into @tb select '0001','2008-01-01',50
insert into @tb select '0001','2008-01-02',100
insert into @tb select '0002','2008-01-02',100
insert into @tb select '0002','2008-02-01',50
insert into @tb select '0003','2008-01-02',100
insert into @tb select '0004','2008-01-05',100
insert into @tb select '0004','2008-01-07',50
insert into @tb select '0004','2008-02-01',100
select * from @tb t where datepart(mm,dt)=1 and dt in
(select top 1 dt from @tb where id=t.id order by dt)id dt price
0001 2008-01-01 00:00:00.000 50
0002 2008-01-02 00:00:00.000 100
0003 2008-01-02 00:00:00.000 100
0004 2008-01-05 00:00:00.000 100没那复杂吧
insert into tb values('0001', '2008-01-01', 50 )
insert into tb values('0001', '2008-01-02', 100 )
insert into tb values('0002', '2008-01-02', 100 )
insert into tb values('0002', '2008-02-01', 50 )
insert into tb values('0003', '2008-01-02', 100 )
insert into tb values('0004', '2008-01-05', 100 )
insert into tb values('0004', '2008-01-07', 50 )
insert into tb values('0004', '2008-02-01', 100 )
go--方法1:
select a.* from tb a where 业务日期 = (select min(业务日期) from tb where month(业务日期) = 1 and 客户编号 = a.客户编号) order by a.客户编号
--方法2:
select a.* from tb a where not exists(select 1 from tb where month(业务日期) = 1 and 客户编号 = a.客户编号 and 业务日期 < a.业务日期)
--方法3:
select a.* from tb a,(select 客户编号,min(业务日期) 业务日期 from tb group by 客户编号) b where month(a.业务日期) = 1 and a.客户编号 = b.客户编号 and a.业务日期 = b.业务日期 order by a.客户编号
--方法4:
select a.* from tb a inner join (select 客户编号 , min(业务日期) 业务日期 from tb group by 客户编号) b on month(a.业务日期) = 1 and a.客户编号 = b.客户编号 and a.业务日期 = b.业务日期 order by a.客户编号
--方法5
select a.* from tb a where 1 > (select count(*) from tb where month(业务日期) = 1 and 客户编号 = a.客户编号 and 业务日期 < a.业务日期) order by a.客户编号
drop table tb/*
客户编号 业务日期 上日余额
---------- ------------------------------------------------------ -----------
0001 2008-01-01 00:00:00.000 50
0002 2008-01-02 00:00:00.000 100
0003 2008-01-02 00:00:00.000 100
0004 2008-01-05 00:00:00.000 100(所影响的行数为 4 行)
*/
drop table tb
go
create table tb(客户编号 varchar(5),业务日期 datetime,上日余额 int)
insert into tb
select '0001','2008-01-01', 50 union all
select '0001','2008-01-02', 100 union all
select '0002','2008-01-02', 100 union all
select '0002',' 2008-02-01', 50 union all
select '0003', '2008-01-02', 100 union all
select '0004', '2008-01-05', 100 union all
select '0004', '2008-01-07', 50 union all
select '0004', '2008-02-01', 100 select a.* from tb a
inner join
(
select 客户编号,min(业务日期) as minDate from tb
group by 客户编号
) b
on a.客户编号=b.客户编号 and a.业务日期=b.minDate
--
比较好理解的
(select top 1 dt from @tb where id=t.id order by dt)