var
  AParams: TParams;
  ASQLTxt: string;
  i: integer;
begin
AParams := TParams.Create(nil);
try
  AParams.CreateParam(ftString, 'pCOGNOME',ptOutput);
  AParams.CreateParam(ftInteger, 'pCODPAZ',ptInput);

  AParams.ParamByName('pCODPAZ').AsInteger := 5;

  ASQLTxt := 'SELECT COGNOME INTO :pCOGNOME FROM NOMI WHERE CODPAZ = :pCODPAZ';

  i := dmStudio.EDB1.Execute(ASQLTxt,AParams);

  ShowMessageFmt('rows: %0:d'#13'code: %1:d - Cognome: %2:s',
                 [i,
                  AParams.ParamByName('pCODPAZ').AsInteger,// Just to check
                  AParams.ParamByName('pCOGNOME').AsString ]);
finally
  AParams.Clear;  
  AParams.Free;
end;