分页问题..

大家好...看了张老师的分页..然后跟着写...什么都做好之后....
可是到了第一页,还能点击上一页...到了最后一页还是可以点击下一页...请教下大家...谢谢.

代码贴出来看看，找找原因

$sql=mysql_query("select * from `table`);
$num=mysql_num_rows($sql);
$count=count($num/$pageval)

<?php
  global $db,$page,$pageval;
     $pagesize=10;
     $url="index.php";
     $numq=mysql_query("SELECT * FROM `news`");
     $num = mysql_num_rows($numq);
     $con=count($num/$pagesize);
     if(isset($_GET['page']))
     {
     $pageval=$_GET['page'];
     if($pageval==0)
     {
         $pageval=1;
     }
      if($pageval>$con+1)
         {
          $pageval=$con+1;
         }
     $page=($pageval-1)*$pagesize;
     $page.=',';
     }
     if($num > $pagesize)
     {
     if($pageval<=1)
     {
         $pageval=1;
     }
     $pageNum= "共 $num 条新闻".
        " <a href=$url&page=".($pageval-1)." target=_parent>上一页</a> <a href=$url&page=".($pageval+1)." target=_parent>下一页</a>";