private function loadWikiListFromDB($userId) { $db = $this->getDB(false); $res = $db->select('wall_notification', ['distinct wiki_id'], ['user_id' => $userId], __METHOD__); $ids = []; foreach ($res as $row) { /** @var Object $row */ $ids[] = $row->wiki_id; } WikiFactory::prefetchWikisById($ids, WikiFactory::PREFETCH_WIKI_METADATA); $output = []; foreach ($ids as $id) { $output[$id] = WikiFactory::getWikiByID($id)->city_title; } return $output; }