if (isset($_POST['priv'])) {
$ids = join(',', $_POST['priv']);
$actions = M('Actions');
$actions->roleid = $id;
$actions->where('`id` in (' . $ids . ')');

if (false == $actions->save()) {
return $this->ajaxReturn(array(
'error' => true,
'message' => $actions->getError()
));
}
}