private static function insert(Conference $model)
 {
     $db = Database::getInstance('app');
     $query = "INSERT INTO conferences (ownerid,administratorid,venueid,name,startdatatime,enddatatime)\r\n                    VALUES (':ownerid', ':administratorid', ':venueid', ':name', ':startdatatime', ':enddatatime')";
     $result = $db->prepare($query);
     $result->execute([':ownerid' => $model->getOwnerId(), ':administratorid' => $model->getAdministratorId(), ':id' => $model->getId(), ':venueid' => $model->getVenueId(), ':name' => $model->getName(), ':startdatatime' => $model->getStartDateTime(), ':enddatatime' => $model->getEndDateTime()]);
     $model->setId((int) $db->lastId());
 }