Update rex_firebase_query plugin, and
Here is a sample capx, remember fill your firebase url in "BASE" constant value.
I only could prove this order by value is worked, but I don't know why it is failed in your case, this bug should not appear imo.
I don't understand... I updated the plugin and tried the sample file you provided.
The only thing I changed was the BASE url like you instructed. Writing to my database from your sample file works, but the query function is in error.
Here's the code that makes the error:
Does it work for you?
*** Update ***
I've been able to get it to work if searching for the key ("a" through "d" in your example). Also, adding the "Data is null" condition triggers correctly when searching for non-existing key "e", for example.
Attached is a screenshot of what does work (when BASE url filled in: https://<appname>.firebaseio.com).
This is good enough for me. Even if I can't search for value, I can at least define and search for the key whether it exists or not. I can then use another query call to get the value if needed.
Thanks again for your help.