# File lib/moped/authenticatable.rb, line 20
    def apply_credentials(logins)
      unless credentials == logins
        logouts = credentials.keys - logins.keys
        logouts.each do |database|
          logout(database)
        end
        logins.each do |database, (username, password)|
          unless credentials[database] == [ username, password ]
            login(database, username, password)
          end
        end
        @original_credentials = credentials.dup
      end
      self
    end