private function getSegmentsOfConfig($configId)
    {
        // get specified config
        $configRepository = $this->em->getRepository('KunstmaanDashboardBundle:AnalyticsConfig');
        $config = $configRepository->find($configId);

        if (!$config) {
            throw new \Exception('Unkown config ID');
        }

        // get the segments
        return $config->getSegments();
    }