/**
  * Clear parts of the Select object, or an individual part.
  *
  * @param string $part
  *            OPTIONAL
  * @return EhrlichAndreas_Db_Update
  */
 public function reset($part = null)
 {
     parent::reset($part);
     return $this;
 }
 /**
  * Render WHERE clause
  *
  * @param string $sql
  *            SQL query
  * @return string
  */
 protected function _renderWhere($sql)
 {
     if ($this->_parts[EhrlichAndreas_Db_Sql::FROM] && $this->_parts[EhrlichAndreas_Db_Sql::WHERE]) {
         $sql = parent::_renderWhere($sql);
     }
     return $sql;
 }