Flutter Firestore Query Nested Subcollections

Question

I am trying to query subcollection in Firebase, but I always get an empty list...

This is my query:

Firestore.instance.collection(\'messages\').where(\'i         


        

Answer 1

Since Firstore queries are always shallow, you have to build the path to the subcollection to query.

Firestore.instance
    .collection('messages')
    .document(...)   // ID of the nested document
    .collection(...).  // ID of the nested subcollection
    .where('idFrom', isEqualTo: userID);

There is no way to avoid giving those nested IDs. If you can't identify the full path of the subcollection to query, you won't be able to access its documents.