class RegularModel < ActiveRecord::Base
end


class MyModel < ActiveRecord::Base
  establish_connection "another_db"
end

# these then use the following, located in database.yml
development:
  adapter: mysql
  database: firstdb
  pool: 5
  timeout: 5000

another_db:
  adapter: mysql
  database: second_db_table
  pool: 5
  timeoute: 5000

Use multiple databases in rails.

Ruby