PHP Seitennavigation: problem beim round()

    public function Navi() {
        $db_result = $this->database->runSQLQuery("SELECT id FROM blog_content WHERE state = 1");
        $count = mysql_num_rows($db_result);
        $round_count = round(($count / ITEM_PRO_SITE) + 0.5, 0);
        $links = '';

        for($i=1; $i<=$round_count; $i++) {
            if($i != $round_count) {
                $links .= '<a href="?site='.$i.'">'.$i.'</a>  &middot; ';
            }
            else {
                $links .= '<a href="?site='.$i.'">'.$i.'</a>';
            }
        }
        return $links;
    }

$db_result = $this->database->runSQLQuery("SELECT count(id) FROM blog_content WHERE state = 1");        
$count = mysql_fetch_row($db_result)[0];

        default:
            if(!$content->checkData()) {
                $tpl->display(TEMPLATE_DIR.'error.html');
            } else {
                if(!isset($_GET['site'])) {
                    $site = '0';
                } else {
                    $site = $_GET['site'] * ITEM_PRO_SITE - ITEM_PRO_SITE;
                }
                $tpl->assign('navigation', $navigation->Navi());
                $tpl->assign('content_array', $content->fetchContenData($filter_state = 1, $site));
                $tpl->display(TEMPLATE_DIR.'content.html');
            }
            break;

    define('ITEM_PRO_SITE', '3');

        $db_result = $this->database->runSQLQuery("
            SELECT *,
            DATE_FORMAT(date, '%d.%m.%Y') AS date_format,
            DATE_FORMAT(date, '%H:%i:%s') AS time_format FROM ".GLOBAL_CONTENT_DB."
            ".($id !== false ? ' WHERE id = ' . $id : '')."
            ".($state !== '' ? ' WHERE state = ' . $state : '')."
            ORDER by date DESC
            ".($site !== '' ? ' LIMIT '.$site.','.ITEM_PRO_SITE : '')."
            ");