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count() (aggregation function)

Returns a count of the records per summarization group (or in total, if summarization is done without grouping).

Can be used only in context of aggregation inside summarize
Use the countif aggregation function to count only records for which some predicate returns true.

Syntax

count()

Returns

Returns a count of the records per summarization group (or in total, if summarization is done without grouping).

Example

This example simply aggregates events by their severity.

events 
    | project severity, original_time
    | where original_time > ago(24h)
    | where severity > 6 
    | summarize EventCount=count() by EventSeverity=severity
    | order by EventSeverity desc

Results

EventSeverity	EventCount
10	245015
9	1401646
8	360175
7	1258226