| id | name |
|---|---|
| 1 | 2 |
| 1 | 1 |
| 1 | 5 |
| 2 | 6 |
| 2 | 3 |
有上图表A，需要mysql查询出如下格式,根据id，把数量汇总一下，怎么写呢，愁死我了
| id | num | sum |
|---|---|---|
| 1 | 2 | 8 |
| 1 | 1 | 8 |
| 1 | 5 | 8 |
| 2 | 6 | 9 |
| 2 | 3 | 9 |
分组group，求和
可以这么写
select t.id, s.name as num, t.sum
from (select id, sum(name) as sum from A group by id) t
left join A s on t.id = s.id;