guestbook-PHP请问Notice:Undefinedvariable

Notice: Undefined variable: rs in /home/sujata/Public/guestbook4/edit.php on line 44 (48,52,56)
44行：

请问问题出在哪里？

edit.php:

admin.php:

 
管理员后台
                 
        

index.php:

include "conn.php"; //连接数据库文件if (!empty($_POST['sub'])) {    $username = $_POST['username'];    $email = $_POST['email'];    $content = $_POST['content'];    $refer_url = $_POST['refer_url'];    $sql = "insert into `user` (`id`,`username`,`dates`,`email`,`content`,`refer_url`) VALUES (null,'$username',now(),'$email','$content','$refer_url')";    $query = mysql_query($sql);    if ($query) {        echo ("已经收到你的信息啦，我们会加快步伐改进的。谢谢你的建议！
");        echo ("5秒后将自动跳转到首页，如果没有跳转你可以直接点击此连接");        header("refresh:5;url='index.php'");    } else {        echo "对不起，忙碌....能重新再试一遍吗？>_< " . mysql_error();        header("refresh:5;url='index.php'");    }}?>