SQL语句练习实例之二——找出销售冠军

复制代码 代码如下:

–销售冠军

–问题：在公司中，老板走进来，要一张每个地区销量前3名的销售额与销售员的报表

—

create table salesdetail

(

Area int not null,

Saler nvarchar(20) not null,

SalerId int not null,

Sales money not null

)

insert salesdetail

select 1,’张三’,15,3000

union select 1,’赵一’,16,3500

union select 1,’钱二’,17,4000

union select 1,’孙三’,18,5000

union select 1,’李四’,19,5000

union select 1,’王五’,11,7000

union select 2,’周边一’,25,3000

union select 2,’李白’,22,4000

union select 2,’张镇东’,23,6000

union select 2,’李宁’,24,1000

union select 3,’李斯’,35,3000

union select 3,’李勇’,33,2000

union select 4,’李逵’,44,5000

union select 4,’宋江’,45,5000

union select 4,’吴用’,42,13000

union select 4,’公孙胜’,43,23000

union select 5,’阮小二’,51,5000

union select 5,’阮小五’,52,5000

union select 5,’林冲’,53,5000

union select 5,’林莽’,54,6000

go

—以下这种写法SQL语句会主动把最小的那一个销售额的所有行，都自动删除，只能得到比最小销售额大的数据

–如果你的最小销售额有3行，最大的只有一行，如地区5所示，只会得到最大的那一行。

–地区4只能得到二行，原因同上。

select * from salesdetail as a

where sales >= (select min(b.sales)

from salesdetail as b where a.Area=b.Area and a.Sales<=b.Sales

–group by sales

having COUNT(distinct b.Saler)<=3)

order by a.Area,a.Sales desc,a.Saler,a.SalerId

go

—使用rank()为每个分区中的每一行分配一个顺序号，如果有重复值，它们都将分配相同的顺序号。

select a.area,a.saler,seq from

(

select area,saler,RANK() over(PARTITION by area order by sales desc) as seq from salesdetail

)a where seq<=3

drop table salesdetail