總和（）由組SQL

Question

我有下同value和id例如在一排數據：

表名：測試

id | amount 
1 | 100 
1 | 100 
1 | 100 
2 | 150 
2 | 150 
2 | 150 
3 | 200 
3 | 200 
3 | 200 
4 | 250 
4 | 250 
4 | 250 

我要總結在每個id只有一行使用下文sql不工作它總結所有行。

"select *, sum(amount) as total from test group by id"; 

我的問題是，可能sum()只有一個row每個id？

想要的輸出？（編輯）

id | amount 
1 | 100 
2 | 150 
3 | 200 
4 | 250 

total : 700 

Answer 1

我的問題是，可能要總結（）只有一排每個ID？

我把它解釋爲你想要的一個值，每個組都有一行。一種方法是聚集的兩個層次：

select sum(amount) 
from (select id, max(amount) as amount 
     from test 
     group by id 
    ) t; 

Answer 2

看起來你需要這個

select *,sum(amount) from (select distinct * from test) as t group by id 

Answer 3

嘗試：

select id, sum(amount)/count(*) as total 
from test 
group by id 

結果：

| id | total | 
|----|-------| 
| 1 | 100 | 
| 2 | 150 | 
| 3 | 200 | 
| 4 | 250 | 

Answer 4

嘗試這種使用subquery-

select sum(amount) from (select distinct id,amount from company7) as tempTable 

Answer 5

試試這個

create table #test 
(id int, amount int) 

insert into #test values (1,100),(1,100),(1,100),(2,150),(2,150),(3,200),(3,250) 

;with cte 
as 
(
select sum(distinct amount) as damount,id 
from #test 
group by id 
) 

select sum(damount) as total from cte 

對於其他DBMS於SQL Server

select sum(damount) as total from (select sum(distinct amount) as damount,id 
from test 
group by id) as it