private function createConversationQueryBuilder()
    {
        return $this->objectManager->createQueryBuilder()
            ->select('c', 'cp', 'p', 't', 'm', 'mp')
            ->from($this->getConversationClass(), 'c')
            ->leftJoin('c.persons', 'cp')
            ->leftJoin('cp.person', 'p')
            ->leftJoin('cp.tags', 't')
            ->leftJoin('c.messages', 'm')
            ->leftJoin('m.persons', 'mp')
            ->orderBy('m.date', 'ASC')
            ->addOrderBy('m.id', 'ASC');
    }