怎样在结果集中进行统计呀？

[Bestregards]

我从数据库中的一个表中得到的结果集a是
id name amount
5 纸 10
6 笔 20
7 墨水 5
8 钢笔 10
从另一张表中得到的结果集b是
id name amount
5 纸 20
9 文具盒 6
想从这两个结果集中得到
id name amount
5 纸 30
6 笔 20
7 墨水 5
8 钢笔 10
9 文具盒 6
写成sql语句怎么写呀？

[WangZWang]

select id,name,amount=sum(amount)
from (
Select * from a
union all
Select * from b ) as t
group by id,name order by id

[dawugui]

select id , name , amount = sum(amount) from
(
Select * from a
union all
Select * from b
) t
group by id , name
order by id

[Bestregards]

但老是说 union all附近语法错误！

[dawugui]

Select * from a
Select * from b

两个查询结果的字段名和类型和顺序必须相同.

[li8848li]

我试了，没问题呀!