public function setOrderBy(QueryBuilder $qb)
    {
        if (isset($this->request['iSortCol_0'])) {
            for ($i = 0; $i < intval($this->request['iSortingCols']); $i++) {
                if ($this->request['bSortable_'.intval($this->request['iSortCol_'. $i])] == "true") {
                    $qb->addOrderBy(
                        $this->associations[$this->request['iSortCol_'.$i]]['fullName'],
                        $this->request['sSortDir_'.$i]
                    );
                }
            }
        }
    }