def METHOD_NAME(self):
    """Updates the readnoise difference image and histogram"""
    # Update the readnoise difference image and histogram, if data exists
    if len(self.query_results) != 0:
        # Get the most recent data; the entries were sorted by time when
        # loading the database, so the last entry will always be the most recent.
        diff_image_png = self.query_results[-1].readnoise_diff_image
        diff_image_png = os.path.join('/static', '/'.join(diff_image_png.split('/')[-6:]))
        diff_image_n = np.array(self.query_results[-1].diff_image_n)
        diff_image_bin_centers = np.array(self.query_results[-1].diff_image_bin_centers)
        # Update the readnoise difference image and histogram
        self.refs['readnoise_diff_image'].image_url(url=[diff_image_png], x=0, y=0, w=2048, h=2048, anchor="bottom_left")
        self.refs['diff_hist_source'].data = {'n': diff_image_n,
                                              'bin_centers': diff_image_bin_centers}
        self.refs['diff_hist_xr'].start = diff_image_bin_centers.min()
        self.refs['diff_hist_xr'].end = diff_image_bin_centers.max()
        self.refs['diff_hist_yr'].start = diff_image_n.min()
        self.refs['diff_hist_yr'].end = diff_image_n.max() + diff_image_n.max() * 0.05
    # Update the readnoise difference image style
    self.refs['readnoise_diff_image'].xaxis.visible = False
    self.refs['readnoise_diff_image'].yaxis.visible = False
    self.refs['readnoise_diff_image'].xgrid.grid_line_color = None
    self.refs['readnoise_diff_image'].ygrid.grid_line_color = None
    self.refs['readnoise_diff_image'].title.text_font_size = '22px'
    self.refs['readnoise_diff_image'].title.align = 'center'