mysql - 根据 mysql 中的先前记录检索记录

Question

经过大量搜索后，我无法找到所需的结果。我有一个表tasktransit，其中包含以下数据:

+---------------+--------+------------+-------------+-------------+------------+
| tasktransitid | taskid | activityid | newsequence | status      | dependency |
+---------------+--------+------------+-------------+-------------+------------+
|             1 | RH001  |          1 |           1 | Not Started |            |
|             2 | RH001  |          2 |           2 | Completed   |            |
|             3 | RH001  |          3 |           4 | Not Started |            |
|             4 | RH001  |          4 |           3 | Not Started |            |
|             5 | RH002  |          3 |           1 | Completed   | NULL       |
|             6 | RH002  |          4 |           2 | Not Started |            |
|             7 | RH003  |          3 |           1 | Not Started | NULL       |
|             8 | RH004  |          4 |           2 | Not Started | NULL       |
+---------------+--------+------------+-------------+-------------+------------+

这里的新闻序列对于一种任务ID来说是唯一的。

I want to get the the taskid where 
activityid=4 AND
status="Not Completed" AND
status="Completed" of previous newsequence.

因此，使用上述类型的 sudo 代码，我想要具有以下值的结果

taskid    | activityid
 1. RH001  |  4

 2. RH002  |  4

如有任何帮助，我们将不胜感激。

Answer 1

我没有找到“未完成”状态。您将条件 where 子句添加为

status="Not Completed" AND status="Completed"

您想要获取未开始还是已完成的列表？

  status="Not Started" OR status="Completed"