anchor.diff:  remove_sub(Filter,ClientId) ->
       Fun =
           fun() ->
  -            mnesia:delete({?SUB_RECORD,{Filter,ClientId}})
  +            mnesia:delete({?SUB_RECORD,?TO_SUB_ID(Filter,ClientId)})
           end,
       mnesia_do(Fun).
   
  
positive.code:     -define(PERSISTENCE, disc_copies).
  -endif.
  
  -define(SUB_RECORD, mqtt_sub).
  -define(SUB_REG_RECORD, mqtt_sub_reg).
  -define(ALL_TABLES,[?SUB_RECORD,?SUB_REG_RECORD]).
  
negative.code: %% @end
  
  -spec save_sub(ClientId::client_id(),
      {Filter::binary(),
       QoS::qos(),
       Seq::integer(),
       ClientPid::pid()}
  ) ->
      {ok,Result::any()}.
  
  save_sub(Filter,{ClientId,QoS,CSeq,ClientPid}) ->
      Fun =
          fun() ->
               R = #mqtt_sub{id = ?TO_SUB_ID(Filter,ClientId),
                             filter = Filter,
                             client_id = ClientId,
                             cseq = CSeq,
  