    public static function getParent($id = '')
    {
        $id = sprintf('%d', $id);
        $sql = sprintf("SELECT `parent` FROM `cat`
                        WHERE `id` = '%d'", $id);
        $cat = Db::result($sql);

        return $cat;
    }
The software constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component.