如果 Term 达到某个点，Kusto row_cumsum 会修改 Term

我有一份按以下顺序排列的员工姓名和工资列表

我需要按以下格式创建输出表。即，每当累计工资总额超过 3000 时，我必须检测到这一点并标记该行。

我尝试过 row_cumsum 并重置Term一旦超过 3000，但第二次迭代就不起作用了。

datatable (name:string, month:int, salary:long)
[
    "Alice", 1, 1000,
    "Alice", 2, 2000,
    "Alice", 3, 1400,
    "Alice", 3, 1400,
    "Alice", 3, 1400,
]
| order by name asc, month asc
| extend total=row_cumsum(salary) 
| extend total=iff(total >=3000,total-prev(total),total)

现在这可以通过扫描操作员:

datatable (name:string, salary:long)
[
    "Alice", 1000,
    "Alice", 2000,
    "Alice", 1400,
    "Alice", 1400,
    "Alice", 1400,
    "Alice", 1000,
    "Bob", 2400,
    "Bob", 1000,
    "Bob", 1000
]
| sort by name asc
| scan declare (total:long) with 
(
    step s: true => total = iff(isnull(s.total) or name != s.name, salary, iff(s.total < 3000, s.total + salary, salary));
)
| extend boundary_detected = iff(total >= 3000, 1, long(null))