retrieve_connection_pool in connection_pool.rb look up connection pool by class name. However, class name is the empty string if the class is created with Class.new(ActiveRecord::Base). If several classes are created that way using different databases, then massive confusion will occur.

I see two possible resolutions to this:
1: Enforce name being != "" when executing estrablish_connection
2: use object_id instead of class name.

Not the biggest issue I guess since it is quite a bit off the normal path of doing things, but it is still not very nice to get silent breakage.