/**
  * Apply authz rules for who may manage.
  *
  * @param AIR2_Query $q
  * @param User    $u
  * @param string  $alias (optional)
  */
 public static function query_may_manage(AIR2_Query $q, User $u, $alias = null)
 {
     if ($u->is_system()) {
         return;
     }
     $a = $alias ? "{$alias}." : "";
     $user_id = $u->user_id;
     $prjq = $q->createSubquery();
     $prjq->select('prj.prj_id');
     $prjq->from('Project prj');
     Project::query_may_manage($prjq, $u);
     $q->addWhere("{$a}prjan_prj_id IN (" . $prjq->getDql() . ")");
     $q->addWhere("{$a}prjan_cre_user = ?", $u->user_id);
 }