countif() (aggregation function)

Syntax

countif (Predicate)

Arguments

Predicate: Expression that will be used for aggregation calculation. Predicate can be any scalar expression with return type of bool (evaluating to true/false).

Example

This query returns a count of rows for which Predicate evaluates to true. Notice the rows which do not match the predicate are still returned, but their records were not counted

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

See also

count() function, which counts rows without predicate expression.