sql语句请教

2009-03-25 10:06:27 108 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

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sql语句请教

有一个员工的薪水表，字段如下：
EmployeeSalary(Table)
EName , Age, Salary (Filed)
现在我想用一条sql语句得到如下数据 Age < 30的平均薪水， 30 <= Age <= 35 的平均薪水 , Age > 35的平均薪水
示例数据
EName Age Salary
a 32 4000
b 25 3000
c 27 3600
e 22 3000
f 37 5000
g 34 4200
h 36 4500

得到如下的三行数据
<30 3200
30 -35 4100
>35 4750

请问使用一条sql语句怎么实现?

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lcyhjx 2009-03-25

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感谢各位，使用group by & cash.. when .then end 是我想要的。union的方式也可以实现，但是不是我想要的饿唧结果，不过也同样感谢各位的回答。结帖了

hcw_peter 2009-03-25

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LZ看看下面的SQL是否是你想要的？？
-------------------------------------------------
select '< 30' as Age,
avg(Salary) as 'AVG Salary'
from EmployeeSalary
where Age < 30
union all
select '30 - 35' as Age,
avg(Salary) as 'AVG Salary'
from EmployeeSalary
where Age between 30 and 35
union all
select '> 35' as Age,
avg(Salary) as 'AVG Salary'
from EmployeeSalary
where Age > 35
-------------------------------------------------

interfacejava 2009-03-25

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只能顶你们速度真快啊

chuifengde 2009-03-25

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哦,平均用avg

liangCK 2009-03-25

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SELECT

    CASE WHEN age<30 THEN 'age<30'

         WHEN age BETWEEN 30 AND 35 THEN '30-35'

         ELSE '>35' END as AGE,

    AVG(Salary) AS Salary

FROM tb

GROUP BY 

    CASE WHEN age<30 THEN 'age<30'

         WHEN age BETWEEN 30 AND 35 THEN '30-35'

         ELSE '>35' END

百年树人 2009-03-25

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---测试数据---

if object_id('[EmployeeSalary]') is not null drop table [EmployeeSalary]

go

create table [EmployeeSalary]([EName] varchar(1),[Age] int,[Salary] int)

insert [EmployeeSalary]

select 'a',32,4000 union all

select 'b',25,3000 union all

select 'c',27,3600 union all

select 'e',22,3000 union all

select 'f',37,5000 union all

select 'g',34,4200 union all

select 'h',36,4500

 

---查询---

select 

  '<30' as age,

  (select avg(salary) from EmployeeSalary where age<30) as Salary

union all

select 

  '30-35',

  (select avg(salary) from EmployeeSalary where age between 30 and 35)

union all

select 

  '>35',

  (select avg(salary) from EmployeeSalary where age>35)





---结果---

age   Salary      

----- ----------- 

<30   3200

30-35 4100

>35   4750



（所影响的行数为 3 行）

chuifengde 2009-03-25

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DECLARE @a TABLE(NAME CHAR(1),age INT,salary INT)

INSERT @a SELECT 'a',        32,        4000 

union all select 'b',        25,        3000 

union all select 'c',        27,        3600 

union all select 'e',        22,        3000 

union all select 'f',        37,        5000 

union all select 'g',        34,        4200 

union all select 'h',        36,        4500



select case when age<30 then '<30'

     when age between 30 and 35 then '30-35'

     else '>35' 

END 年龄 

,SUM(salary) 平均薪水

from @a

group by

case when age<30 then '<30'

     when age between 30 and 35 then '30-35'

     else '>35' 

end



--result

/*年龄    平均薪水        

----- ----------- 

<30   9600

>35   9500

30-35 8200



（所影响的行数为 3 行）



*/

dawugui 2009-03-25

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create table tb(EName varchar(10), Age int,Salary int)

insert into tb values('a' ,       32 ,       4000 )

insert into tb values('b' ,       25 ,       3000 )

insert into tb values('c' ,       27 ,       3600 )

insert into tb values('e' ,       22 ,       3000 )

insert into tb values('f' ,       37 ,       5000 )

insert into tb values('g' ,       34 ,       4200 )

insert into tb values('h' ,       36 ,       4500 )

go



select item,avg(Salary)

from

(

select 

  case when Age < 30 then '<30'

       when age between 30 and 35 then '30-35'

       when age > 35 then '>35'

  end item,

  *

from tb

) t

group by item



drop table tb



/*

item              

----- ----------- 

<30   3200

>35   4750

30-35 4100



（所影响的行数为 3 行）

*/

百年树人 2009-03-25

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select 

  '<30' as age,

  (select avg(salary) from EmployeeSalary where age<30)

union all

select 

  '30-35',

  (select avg(salary) from EmployeeSalary where age between 30 and 35)

union all

select 

  '>35',

  (select avg(salary) from EmployeeSalary where age>35)

dawugui 2009-03-25

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select item,avg(Salary)

from

(

select 

  case when Age < 30 then '<30'

       when age between 30 and 35 then '30-35'

       when age > 35 then '35'

  end item,

  *

from tb

) t

group by item

sql语句请教

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