ActiveRecord without an associated model


I know it could seem a very strange topic, but, I’m working with
temporal SQL tables and I want to use ActiveRecord to work with them,
connect to the database, manage erroes, etc; but, I don’t want to add
a new model to my application.

It is, I want a kind of find_by_sql that could be associate to a Empty
class, or something like that.

Any ideas?