isnull()

Applies to: ✅ Azure Data Explorer ✅ Azure Monitor ✅ Microsoft Sentinel

Evaluates an expression and returns a Boolean result indicating whether the value is null.

Syntax

isnull(Expr)

Learn more about syntax conventions.

Parameters

Returns

Returns true if the value is null and false otherwise. Empty strings, arrays, property bags, and objects always return false.

The following table lists return values for different expressions (x):

Example

Find the storm events for which there's no begin location.

StormEvents
| where isnull(BeginLat) and isnull(BeginLon)
| project StartTime, EndTime, EpisodeId, EventId, State, EventType, BeginLat, BeginLon

Output