PHP Pagination Error

[vizz]

For following code I am receiving error, Notice: Undefined index: page
Code is running perfectly but there is only one error of notice.

I have marked line as //this is error part for which I am getting error (line number 19 or 20)

<?php
/*Place code to connect to your DB here.*/
include('config.php');  // include your code to connect to DB.

$tbl_name="";       //your table name

$adjacents = 3;     // How many adjacent pages should be shown on each side?

/*First get total number of rows in data table.If you have a WHERE clause in your query, make sure you mirror it here.*/

$query = "SELECT COUNT(*) as num FROM $tbl_name";
$total_pages = mysql_fetch_array(mysql_query($query));
$total_pages = $total_pages[num];

/* Setup vars for query. */
$targetpage = "filename.php";          //your file name  (the name of this file)
$limit = 2;                           //how many items to show per page

$page = $_GET['page']; //this is error part

if($page) 
    $start = ($page - 1) * $limit;          //first item to display on this page
else
    $start = 0;                             //if no page var is given, set start to 0

/* Get data. */
$sql = "SELECT column_name FROM $tbl_name LIMIT $start, $limit";
$result = mysql_query($sql);

/* Setup page vars for display. */
if ($page == 0) $page = 1;                  //if no page var is given, default to 1.
$prev = $page - 1;                          //previous page is page - 1
$next = $page + 1;                          //next page is page + 1
$lastpage = ceil($total_pages/$limit);      //lastpage is = total pages / items per page, rounded up.
$lpm1 = $lastpage - 1;                      //last page minus 1

/* 
    Now we apply our rules and draw the pagination object. 
    We're actually saving the code to a variable in case we want to draw it more than once.
*/
$pagination = "";
if($lastpage > 1)
{   
    $pagination .= "<div class=\"pagination\">";
    //previous button
    if ($page > 1) 
        $pagination.= "<a href=\"$targetpage?page=$prev\">� previous</a>";
    else
        $pagination.= "<span class=\"disabled\">� previous</span>";   

    //pages 
    if ($lastpage < 7 + ($adjacents * 2))    //not enough pages to bother breaking it up
    {   
        for ($counter = 1; $counter <= $lastpage; $counter++)
        {
            if ($counter == $page)
                $pagination.= "<span class=\"current\">$counter</span>";
            else
                $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";                   
        }
    }
    elseif($lastpage > 5 + ($adjacents * 2))    //enough pages to hide some
    {
        //close to beginning; only hide later pages
        if($page < 1 + ($adjacents * 2))     
        {
            for ($counter = 1; $counter < 4 + ($adjacents * 2); $counter++)
            {
                if ($counter == $page)
                    $pagination.= "<span class=\"current\">$counter</span>";
                else
                    $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";                   
            }
            $pagination.= "...";
            $pagination.= "<a href=\"$targetpage?page=$lpm1\">$lpm1</a>";
            $pagination.= "<a href=\"$targetpage?page=$lastpage\">$lastpage</a>";     
        }
        //in middle; hide some front and some back
        elseif($lastpage - ($adjacents * 2) > $page && $page > ($adjacents * 2))
        {
            $pagination.= "<a href=\"$targetpage?page=1\">1</a>";
            $pagination.= "<a href=\"$targetpage?page=2\">2</a>";
            $pagination.= "...";
            for ($counter = $page - $adjacents; $counter <= $page + $adjacents; $counter++)
            {
                if ($counter == $page)
                    $pagination.= "<span class=\"current\">$counter</span>";
                else
                    $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";                   
            }
            $pagination.= "...";
            $pagination.= "<a href=\"$targetpage?page=$lpm1\">$lpm1</a>";
            $pagination.= "<a href=\"$targetpage?page=$lastpage\">$lastpage</a>";     
        }
        //close to end; only hide early pages
        else
        {
            $pagination.= "<a href=\"$targetpage?page=1\">1</a>";
            $pagination.= "<a href=\"$targetpage?page=2\">2</a>";
            $pagination.= "...";
            for ($counter = $lastpage - (2 + ($adjacents * 2)); $counter <= $lastpage; $counter++)
            {
                if ($counter == $page)
                    $pagination.= "<span class=\"current\">$counter</span>";
                else
                    $pagination.= "<a href=\"$targetpage?page=$counter\">$counter</a>";                   
            }
        }
    }

    //next button
    if ($page < $counter - 1) 
        $pagination.= "<a href=\"$targetpage?page=$next\">next �</a>";
    else
        $pagination.= "<span class=\"disabled\">next �</span>";
    $pagination.= "</div>\n";        
}
?>

<?php
    while($row = mysql_fetch_array($result))
    {

    // Your while loop here

    }
?>

<?=$pagination?>

$page = $_GET['page']; //this is error part
if($page) 
    $start = ($page - 1) * $limit;          //first item to display on this page
else
    $start = 0;                             //if no page var is given, set start to 0

to

if(isset($_GET['page'])){
    $start = ($_GET['page'] - 1) * $limit; 
}else{ 
    $start = 0;          //first item to display on this page
}

However I would suggest a further test where you check the value of $_GET['page'] to ensure that it's in range. If greater than the no. of pages, change to max. If leass than 0, change to 0. You may find intval() useful if somebody messes with the querystring and enters some text.

[vizz]

Thanks