anchor.diff:  
               {ok, ID};
           E ->
  -            lager:info("[dqe_idx:pg:add/4] Query failed after ~pms: ~s <- ~p",
  -                       [dqe_idx_pg:tdelta(T0), Q, Vs]),
  +            lager:info("[dqe_idx:pg:add/4] Query failed after ~pms: ~s <- ~p:"
  +                       " ~p", [dqe_idx_pg:tdelta(T0), Q, Vs, E]),
               E
       end.
   
  
positive.code:             ok;
          E ->
              lager:info("[dqe_idx:pg:delete/4] Query failed after ~pms: "
                         "~s <- ~p", [tdelta(T0), Q, Vs]),
              E
      end.
  
  
negative.code:                     {ok, MID};
                  E ->
                      lager:info("[dqe_idx:pg:add/5] Query failed after ~pms: "
                                 "~s <- ~p: E",
                                 [dqe_idx_pg:tdelta(T0), Q, Vs, E]),
                      E
              end;
          EAdd ->
  