> ## Documentation Index
> Fetch the complete documentation index at: https://docs.activeviam.com/llms.txt
> Use this file to discover all available pages before exploring further.

# ExternalColumn.isnull()

<span id="atoti.ExternalColumn.isnull" />

> ExternalColumn.isnull() → RelationalCondition\[TypeVar, 'EQ', NoneType]

Return a condition evaluating to `True` where this container evaluates to `None`, and evaluating to `False` elsewhere.