Teradata (ANSI SQL) 和 Oracle/My SQL 关于 sum(x) over（按 y 顺序分区）有什么区别？

Question

原始表X为：

ID	START_DATE	END_DATE	GRP
001	2017-10-15	2018-10-21	1
001	2017-10-15	2019-10-21	0
001	2020-05-18	2021-05-03	1

select ID, start_date, end_date,
sum(grp) over(partition by ID order by start_date, end_date) as island
from X
```


In Teradata the result is:


| ID       | START_DATE   | END_DATE | island |
| -------- | ------------ | -------- |------- |
| 001      | 2017-10-15   |2018-10-21|  2     |
| 001      | 2017-10-15   |2019-10-21|  2     |
| 001      | 2020-05-18   |2021-05-03|  2     |


In Oracle and MySQL the results are: 
| ID       | START_DATE   | END_DATE | island |
| -------- | ------------ | -------- |------- |
| 001      | 2017-10-15   |2018-10-21|  1     |
| 001      | 2017-10-15   |2019-10-21|  1     |
| 001      | 2020-05-18   |2021-05-03|  2     |

Any suggestions to fix the Teradata result? Many thanks !!