我有两个表，一个存储数据的子级和父级，其他路径和后代
+----------+------------+-----------+
| userid | parent | price |
+----------+------------+------------
| 1 | null | 20 |
| 2 | 1 | 20 |
| 3 | 1 | 20 |
| 4 | 2 | 20 |
| 5 | 2 | 20 |
| 6 | 3 | 20 |
| 7 | 4 | 20 |
+----------+------------+-----------+
我需要获取所有具有父代1的用户ID，然后获取其他表中的子代，并按用户ID总价分组
+-------------+---------------+-------------+
| ancestor_id | descendant_id | path_length |
+-------------+---------------+-------------+
| 1 | 1 | 0 |
| 1 | 2 | 1 |
| 1 | 3 | 1 |
| 1 | 4 | 2 |
| 1 | 5 | 2 |
| 1 | 6 | 2 |
| 1 | 7 | 3 |
| 2 | 2 | 0 |
| 2 | 4 | 1 |
| 2 | 5 | 1 |
| 2 | 7 | 2 |
| 3 | 3 | 0 |
| 3 | 6 | 1 |
| 4 | 4 | 0 |
| 4 | 7 | 1 |
| 5 | 5 | 0 |
| 6 | 6 | 0 |
| 7 | 7 | 0 |
+-------------+---------------+-------------+
我已经查询了所有孩子的总和
select
sum(b.price)
from webineh_prefix_nodes_paths_tmp a
join webineh_prefix_nodes_tmp b on (b.userid = a.descendant_id)
where a.ancestor_id = 1
这项工作很好，但父母总和为1
我需要显示直接儿童的波纹管结果（2,3）
+----------+------------+-
| userid | total |
+----------+------------+
| 2 | 80 |
| 3 | 40 |
+----------+------------+
同样在创建sqlfiddle我的问题http://sqlfiddle.com/#!9/9415ed/2
最佳答案
尝试这个;）
select ancestor_id as userid, sum(b.price) as total
from webineh_prefix_nodes_paths_tmp a
join webineh_prefix_nodes_tmp b
on b.userid = a.descendant_id
where a.ancestor_id in (select userid from webineh_prefix_nodes_tmp where parent = 1)
group by ancestor_id
SQLFiddle Demo
已编辑
select ancestor_id as userid, sum(b.price) as total
from webineh_prefix_nodes_paths_tmp a
join webineh_prefix_nodes_tmp b
on b.userid = a.descendant_id
inner join webineh_prefix_nodes_tmp c
on a.ancestor_id = c.userid
and c.parent = 1
group by ancestor_id
SQLFiddle Demo
关于mysql - 其他表mysql中子项的总价，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/38209563/