anchor.diff:  plfr(Q) ->
       plfr(Q,[]).
   
  +-spec tfr(Q :: sql()) -> tuple() | not_found.
   tfr(Q) ->
       tfr(Q,[]).
   
  +-spec tfr(Q :: sql(), ParamList :: [value()]) -> tuple() | not_found.
   tfr(Q,ParamList) ->
       case tq(Q,ParamList) of
           [] -> not_found;
  
positive.code:     V.
  
  -spec format_key(K :: field()) -> atom().
  format_key(K) when is_atom(K) ->
      K;
  format_key(K) when is_binary(K) ->
  
negative.code:     end.
  
  %% fr = First Record
  -spec fr(Q :: sql(), ParamList :: [value()]) -> list() | not_found.
  fr(Q,ParamList) ->
      case q(Q,ParamList) of
          [] -> not_found;
  