[look]

aqui un ejemplo:

Código Delphi [-]
  if not (DataModule.IBTransaction1.InTransaction) then DataModule.IBTransaction1.StartTransaction;
  try

     ////     aqui los cambios en la base de datos      insert, update..

      DataModule.IBTransaction1.CommitRetaining;
  except
    on E: Exception do
    begin
          DataModule.IBTransaction1.RollbackRetaining;
          Application.MessageBox( PCHAR('Ocurrio un error.'+#13+E.MESSAGE), 'Error',MB_ICONERROR );
          exit;
    end;
  END;