Checks whether this data model is in updating mode or not. Updating
mode is set to TRUE when gda_data_model_begin_update has been
called successfully, and is not set back to FALSE until either
gda_data_model_cancel_update or gda_data_model_end_update have
been called.
Checks whether this data model is in updating mode or not. Updating mode is set to TRUE when gda_data_model_begin_update has been called successfully, and is not set back to FALSE until either gda_data_model_cancel_update or gda_data_model_end_update have been called.