public function revokePagePrivileges(Page $page)
    {
        if ($this->revokePageStatement == null) {
            $this->revokePageStatement =
                $this->connection->prepare("DELETE FROM UserPrivileges WHERE username = ? AND pageId = ?");
        }
        $this->revokePageStatement->execute(array($this->user->getUsername(), $page->getID()));
        unset($this->pagePrivilege[$page->getID()]);
    }