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sample-distinct operator
Applies to: ✅ Microsoft Fabric ✅ Azure Data Explorer ✅ Azure Monitor ✅ Microsoft Sentinel
Returns a single column that contains up to the specified number of distinct values of the requested column.
The operator tries to return an answer as quickly as possible rather than trying to make a fair sample.
Syntax
T | sample-distinct NumberOfValues of ColumnName
Learn more about syntax conventions.
Parameters
| Name | Type | Required | Description |
|---|---|---|---|
| T | string |
✔️ | The input tabular expression. |
| NumberOfValues | int, long, or real | ✔️ | The number distinct values of T to return. You can specify any numeric expression. |
| ColumnName | string |
✔️ | The name of the column from which to sample. |
Tip
- Use the top-hitters operator to get the top values.
- Refer to the sample operator to sample data rows.
Examples
Get 10 distinct values from a population
StormEvents | sample-distinct 10 of EpisodeId
Sample a population and do further computation without exceeding the query limits in the summarize
let sampleEpisodes = StormEvents | sample-distinct 10 of EpisodeId;
StormEvents
| where EpisodeId in (sampleEpisodes)
| summarize totalInjuries=sum(InjuriesDirect) by EpisodeId