1
我有两个表,我想获得按标记分组的任务的日志记录总和,大多数时间子任务具有与父母,但在某些情况下,他们不。如果从子任务标记为空,从父任务继承标记
如何获取按标记分组的记录分钟总数,包括子任务,因此如果他们没有标记,他们会继承父标记。
任务
+-----+-----------+------+-------+------------+
| id | parent-id | name | tag | is-subtask |
+-----+-----------+------+-------+------------+
| 001 | | a | sales | 0 |
| 002 | 001 | b | sales | 1 |
| 003 | 001 | c | | 1 |
| 004 | | d | store | 0 |
+-----+-----------+------+-------+------------+
次
+-----+---------+-------------+----------------+
| id | task-id | description | logged-minutes |
+-----+---------+-------------+----------------+
| 991 | 001 | Time for a | 15 |
| 992 | 002 | Time for ab | 60 |
| 993 | 002 | Time for ab | 75 |
| 994 | 003 | Time for ac | 35 |
| 995 | 004 | Time for d | 20 |
+-----+---------+-------------+----------------+