Realtime Database: Database listener clears children when performing another query in same ref

[diegogarciar]

Description

For a chat application I am doing a double query, I have a listener for new messages, and a paginated query for old messages.

I just discovered that my listener is impacted by the queries I do on that same path, which I believe shouldn't be the case

Reproducing the issue

  final database = FirebaseDatabase.instance;

  final path = '/test_path';
  String? randomKey;
  for (var i = 0; i < 10; i++) {
    final ref = database.ref(path).push();
    if (i == 5) {
      randomKey = ref.key;
    }
    await ref.set('test $i');
  }

  final ref = database.ref(path);
  var hasQueried = false;
  ref.orderByKey().startAt(randomKey).onValue.listen((event) {
    print('listener  ${event.snapshot.children.length}');

    if (!hasQueried) {
      hasQueried = true;
      ref.orderByKey().limitToLast(3).endBefore(randomKey).get().then((data) {
        print('obtained previous messages ${data.children.length}');
      });
    }
  });

Firebase SDK Version

11.2

Xcode Version

16.1

Installation Method

CocoaPods

Firebase Product(s)

Database

Targeted Platforms

iOS

Relevant Log Output

listener  5
obtained previous messages 3
listener  0

If using Swift Package Manager, the project's Package.resolved

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If using CocoaPods, the project's Podfile.lock

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[google-oss-bot]

I couldn't figure out how to label this issue, so I've labeled it for a human to triage. Hang tight.

[diegogarciar]

The issue was first reported here https://github.com/firebase/flutterfire/issues/13822, will submit the Podfile.lock shortly!

[paulb777]

May be related to long-standing #12168

[ncooke3]

Closing in favor of https://github.com/firebase/firebase-ios-sdk/issues/12168.