row_cumsum()
Applies to: ✅ Microsoft Fabric ✅ Azure Data Explorer ✅ Azure Monitor ✅ Microsoft Sentinel
Calculates the cumulative sum of a column in a serialized row set.
Syntax
row_cumsum( term [, restart] )
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| term | int, long, or real | ✔️ | The expression indicating the value to be summed. |
| restart | bool |
Indicates when the accumulation operation should be restarted, or set back to 0. It can be used to indicate partitions in the data. |
Returns
The function returns the cumulative sum of its argument.
Examples
The following example shows how to calculate the cumulative sum of the first few even integers.
datatable (a:long) [
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
]
| where a%2==0
| serialize cs=row_cumsum(a)
| a | cs |
|---|---|
| 2 | 2 |
| 4 | 6 |
| 6 | 12 |
| 8 | 20 |
| 10 | 30 |
This example shows how to calculate the cumulative sum (here, of salary)
when the data is partitioned (here, by name):
datatable (name:string, month:int, salary:long)
[
"Alice", 1, 1000,
"Bob", 1, 1000,
"Alice", 2, 2000,
"Bob", 2, 1950,
"Alice", 3, 1400,
"Bob", 3, 1450,
]
| order by name asc, month asc
| extend total=row_cumsum(salary, name != prev(name))
| name | month | salary | total |
|---|---|---|---|
| Alice | 1 | 1000 | 1000 |
| Alice | 2 | 2000 | 3000 |
| Alice | 3 | 1400 | 4400 |
| Bob | 1 | 1000 | 1000 |
| Bob | 2 | 1950 | 2950 |
| Bob | 3 | 1450 | 4400 |