I'm trying to pass the documents that i have in a collection to another one, i already copy the documents in the old collection to the new one but now i dont know how to delete the old documents

For now i have this:

FirebaseFirestore.instance
          .collection('users')
          .doc(user.uid)
          .collection('shoplist')
          .get()
          .then((querySnapshot) => {
                querySnapshot.docs.forEach((result) {
                  FirebaseFirestore.instance
                      .collection('users')
                      .doc(user.uid)
                      .collection('history')
                      .doc()
                      .set(result.data())
                      .then((value) => querySnapshot.docs.delete()); // Here is where i don't know what to do
                })
              });

CodePudding user response：

You're trying to delete all documents in the QuerySnapshot in one call, which isn't possible. Instead, you should delete each document after you've written the copy, with:

  FirebaseFirestore.instance
      .collection('users')
      .doc(user.uid)
      .collection('history')
      .doc()
      .set(result.data())
      .then((value) => result.reference.delete()); //