Manage multiple databases in Rails. Connect to different DB based on the model.
http://stackoverflow.com/questions/6122508/connecting-rails-3-1-with-multiple-databases, http://ilikestuffblog.com/2012/09/21/establishing-a-connection-to-a-non-default-database-in-rails-3-2-2/, https://www.linkedin.com/groups/Multiple-Databases-Rails-31-120725.S.55484639