function update($force_create_new_version = true)
 {
     if (!parent::update($force_create_new_version)) {
         return false;
     }
     if ($force_create_new_version) {
         if (!$this->_create_version_record()) {
             return false;
         }
         if ($this->_create_versioned_content_record() !== false) {
             return true;
         }
         debug::write_error('creation of versioned record failed', __FILE__ . ' : ' . __LINE__ . ' : ' . __FUNCTION__);
         return false;
     }
     return $this->_update_versioned_content_record();
 }