Firebase: flutter want to get a null value

Question

I want to get data that is null in a Firebase database

stream: Firestore.instance
      .collection('resep')
      .where("email", isEqualTo: null)
      .snapshots(),

I want to get email data that is null

Answer 1

From the documentation:

where(dynamic field, { dynamic isEqualTo, dynamic isLessThan, dynamic isLessThanOrEqualTo, dynamic isGreaterThan, dynamic isGreaterThanOrEqualTo, dynamic arrayContains, bool isNull }) → Query Creates and returns a new Query with additional filter on specified field. field refers to a field in a document. [...]

There is a isNull property