Firebase deep querying

Question

This question is about implementing firebase deep querying. Consider the following structure in firebase:

Here, my ref is pointing to the root of the structure which is /messages. So I have :

var ref = new Firebase("https://cofounder.firebaseio.com/messages");

I wish to query those message Id's having member = -752163252 . So basically the returned object should be the one with key 655974744 . How do I go about doing this in firebase?

Here's what I tried in my console:

ref.orderByChild("members").equalTo(235642888).on('value', function(snap){console.log("Found ",snap.val())});

Result was:

VM837:2 Found  null

I sense there is a missing link somewhere. Basically, I want to know if there is any way to query the deep nested data without having the parent key id's (in this case 25487894,655974744) .

Also, if I may extend my question, is there a way to add a listener that calls back when a new messageId (in this case 25487894,655974744) is added containing member = -752163252 .

Hope my question is clear enough. Any help is greatly appreciated!

EDIT:

I have already looked at the dinosaurs example, and that's how I tried what I tried but it didn't work.

Answer 1

Your query asserts that the "members" node is an integer with value 235642888, which it is not, naturally. It's an object containing a list of keys.

Instead, you would want to use the deep child query syntax and something like the following:

ref.orderByChild("members/235642888").equalTo(235642888);

Note that you don't really need the value of the key to be the key itself. You could save storage by just setting this to a binary true or 1. The query would be much the same:

ref.orderByChild("members/235642888").equalTo(true);