code: def load_more_data(self, value, rows=False, columns=False):
          
          try:
              if rows and value == self.verticalScrollBar().maximum():
                  self.model().fetch_more(rows=rows)
                  self.sig_fetch_more_rows.emit()
              if columns and value == self.horizontalScrollBar().maximum():
                  self.model().fetch_more(columns=columns)
                  self.sig_fetch_more_columns.emit()
  
          except NameError:
              # Needed to handle a NameError while fetching data when closing
              # See issue 7880
              pass
docs: Load more rows and columns to display.