My session auto destroyed after query from signup table

Question

My user registration table name is "signup". I have many table. But when I query from "signup" table then my session automatically destroyed. But another table has no problem. How can i overcome from this problem? Here is my code

 $id=$_GET['id'];
                     $sql="SELECT * FROM signup WHERE id='$id'";                        
                    $result=mysql_query($sql);
                     $row = mysql_fetch_array($result);
                    if ($row['new_khatian']==1) {$new_khatian="checked";} 
                    echo $new_khatian;

Answer 1

检查一下将session_destroy（）函数放在哪里。上面的代码与我认为的会话没有任何关系。