Profile view

For example:
suppose your user profile url is in the form "http://www.yoursite.com/profile.php?userid=23124"
If a logged in user is visiting another user's profile
 via above url the userid can be accessed using $_GET['userid'];
then the code should be like this

<?php
session_start();
uid of visiting user. Can be retrieved from current session
$logged_user=$_SESSION["current_user_id"];

//extract the user id of visiting profile
$u=$_GET['userid'];

$Owner = "no";
if($u == $logged_user)
{
    $Owner = "yes";
    if($logged_user!==$isOwner)
    {
        $query = mysql_query("UPDATE users SET pvs = pvs + 1 WHERE username =$u'") or die(mysql_error());
    }
}
?>