around_filter :hijack_db

def hijack_db
  begin
    ActiveRecord::Base.connection = ActiveRecord::Base.establish_connection(
      :adapter => "mysql",
      :host => "localhost",
      :username => "root",
      :password => "",
      :database => @nejaka_ta_db
    )

    yield
  rescue Mysql::Error
  # DB NEEXISTUJE NEBO JE NEJAKY PROBLEM
  ensure
    # nakonec to vracime zpet
    ActiveRecord::Base.establish_connection( RAILS_ENV.to_sym )
  end
end