discuz でこのように入力できないのはなぜですか?

<?php<br /><br />/**<br /> *      [Discuz!] (C)2001-2099 Comsenz Inc.<br /> *      This is NOT a freeware, use is subject to license terms<br /> *<br /> *      $Id: forum.php 33828 2013-08-20 02:29:32Z nemohou $<br /> */<br /><br /><br />define('APPTYPEID', 88);<br />define('CURSCRIPT', 'test');<br /><br /><br />require './source/class/class_core.php';<br /><br /><br />require './source/function/function_forum.php';<br /><br /><br /><br />C::app()->init();<br /><br /><br />$squery=DB::query("SELECT catname FROM".DB::table('portal_category'));  <br />while($value=DB::fetch($squery))<br />{<br />	$data[]=$value;<br />}<br />print_r($data);<br />?>

$squery=DB::query("SELECT catname FROM ".DB::table('portal_category'));