title: In Firebase, is there a way to get the number of children of a node without loading all the node data?
body: <p>You can get the child count via</p>
  
  <pre><code>firebase_node.once('value', function(snapshot) { alert('Count: ' + snapshot.numChildren()); });
  </code></pre>
  
  <p>But I believe this fetches the entire sub-tree of that node from the server. For huge lists, that seems RAM and latency intensive. Is there a way of getting the count (and/or a list of child names) without fetching the whole thing?</p>