This API is subject to change. Bug fixes and new features will be released based on developer feedback throughout the preview period.
Refines a query to match items whose specified property has any value.
The isNotEmpty() method refines this query to only match items where the
value of the specified property is not null or undefined.
If the property contains any value at all for a given item, including the empty string or an invalid value, that item will match the query.
Field in which to check for a value.