public static function wipeOldPreviews() { foreach (SongDao::getListOfUnusedPreviews() as $song) { Logger::printf("Wiping old track preview (file id %s)", $song[TSongs::PREVIEW_ID]); FileServer::unregister($song[TSongs::PREVIEW_ID]); SongDao::updateSongUsingId($song[TSongs::ID], [TSongs::PREVIEW_ID => null]); } }