public function addRoleForUser($userId, $roleName)
    {
        $roleIdExpression = new Expression(
            '(SELECT `id` from `user_roles` WHERE `name` = ?)',
            $roleName
        );

        $query = $this->getSqlObject()
            ->insert()
            ->values([
                'user_id' => $userId,
                'role_id' => $roleIdExpression,
            ]);

        $this->execute($query);
    }