public function reset($part = null)
    {
        if ($part == null) {
            $this->_parts = self::$_partsInit;
        } else if (array_key_exists($part, self::$_partsInit)) {
            $this->_parts[$part] = self::$_partsInit[$part];
        }
        return $this;
    }
public function reset($part = null)
    {
        if ($part == null) {
            $this->_parts = self::$_partsInit;
        } else if (array_key_exists($part, self::$_partsInit)) {
            $this->_parts[$part] = self::$_partsInit[$part];
        }
        return $this;
    }
public function reset ( $ part = null ) { if ( $ part == null ) { $ this -> _parts = self :: $ _partsInit ; } else if ( array_key_exists ( $ part , self :: $ _partsInit ) ) { $ this -> _parts [ $ part ] = self :: $ _partsInit [ $ part ] ; } return $ this ; }
Clear parts of the Select object, or an individual part.

@param string $part OPTIONAL
@return Zend_Db_Select
Clear parts of the Select object or an individual part .