PHP - Easier Way To Write This Simple Code?

Hello, I'm new to PHP and I have come up with the following code for my navigation but I am sure there has to be an easier and more efficient way to do this. Someone please start me on the right path. Thanks
Code: [Select]
<?php 
//Get selected page/sub page
if (isset($_GET['page'])) {
$sel_page = $_GET['page'];
$sel_sub_page = '';
} elseif (isset($_GET['sub_page'])) {
$sel_page = '';
$sel_sub_page = $_GET['sub_page'];
      } else {
$sel_page = '';
$sel_sub_page = '';
}
?> Code: [Select]
<!--Begin Navigation-->
<ul>
<?php
//run the loop to get the page titles  
$query = "SELECT * FROM pages ORDER BY position ASC";
$page_set = mysql_query($query);
confirm_query($page_set);
while($page = mysql_fetch_array($page_set)){
echo '<li><a href="content.php?page=' . urlencode($page['id']) . '">' . $page['page_name'] . '</a></li>';
//run sub page query to see if the ul tag is needed
$query = "SELECT * FROM sub_pages WHERE page_id = {$page['id']} ORDER BY position ASC";
$sub_page_set = mysql_query($query);
confirm_query($sub_page_set); 
$sub_page = mysql_fetch_array($sub_page_set);
if ($sub_page !=''){
echo '<ul>';
}
//run the sub page loop again to display the sub page title
$query = "SELECT * FROM sub_pages WHERE page_id = {$page['id']} ORDER BY position ASC";
$sub_page_set = mysql_query($query);
confirm_query($sub_page_set); 
while($sub_page = mysql_fetch_array($sub_page_set)) {
echo '<li><a href="content.php?sub_page=' . urlencode($sub_page['id']) . '">' . $sub_page['page_name'] . '</a></li>';
}
//run the sub page loop for the last time to see if the end ul tag is needed
$query = "SELECT * FROM sub_pages WHERE page_id = {$page['id']} ORDER BY position ASC";
$sub_page_set = mysql_query($query);
confirm_query($sub_page_set); 
$sub_page = mysql_fetch_array($sub_page_set);
if ($sub_page !='') {
echo '</ul>';
}
}
?>
</ul>
<!--End Navigation-->

HI,
My code works but I was wondering if there's a simpler/cleaner way to code it ...

Code: [Select]
<?php
require_once('config.php');

// code to get data form database
mysql_select_db($database, $makeconnection);
$sql_get_categories = "
 SELECT * 
 FROM tbl_categories
 ORDER BY category_id ASC";
$get_categories = mysql_query($sql_get_categories, $makeconnection) or die(mysql_error());
$row_get_categories = mysql_fetch_assoc($get_categories);
$totalRows_get_categories = mysql_num_rows($get_categories);

// i named the 3 fields form the form in the HTML so i can update them into the tadabase
$category_1 = $_POST['category_1'];
$category_2 = $_POST['category_2'];
$category_3 = $_POST['category_3'];

//updating the databse
if (isset($_POST['submitted_categories'])&&($_POST['submitted_categories'] == "yes")) {
$register_query = "SELECT category_id FROM tbl_categories WHERE category_id='$category_id'";
 
mysql_select_db($database, $makeconnection);
$sql_modify1 = ("UPDATE `tbl_categories` SET `category_name` = '$category_1' WHERE `category_id` =1");
$sql_modify2 = ("UPDATE `tbl_categories` SET `category_name` = '$category_2' WHERE `category_id` =2");
$sql_modify3 = ("UPDATE `tbl_categories` SET `category_name` = '$category_3' WHERE `category_id` =3");

$Result1 = mysql_query($sql_modify1, $makeconnection) or die(mysql_error()); 
$Result2 = mysql_query($sql_modify2, $makeconnection) or die(mysql_error());
$Result3 = mysql_query($sql_modify3, $makeconnection) or die(mysql_error());
header ("Location: the-rest.php");
}
?>

here's the form in the html part

Code: [Select]
<!--CATEGORIES -->
<h2>Categories</h2>
<form action="" method="post" enctype="multipart/form-data" name="category-form" id="category-form">
<?php do { ?>
<h3><input class="user-form-input" id="category_<?php echo $row_get_categories['category_id'];?>" name="category_<?php echo $row_get_categories['category_id'];?>" type="text" value="<?php echo $row_get_categories['category_name'];?>" /></h3>
<?php } while ($row_get_categories = mysql_fetch_assoc($get_categories)); ?>
<input name="submitted_categories" type="hidden" id="submitted_categories" value="yes" />
<input name="submit" type="submit" class="button-save" id="submit" value="update categories"/>
</form>
<!--END OF CATEGORIES-->

Something I have never done, but want to learn the best practice for doing so, is a listener script.

Example: one of our websites is in bespoke PHP and has two links that shows if there are any noticeboard 'notifications' or any new 'messages'.

Ideally I'd like to show 1, 2, 3... etc as a count of how many are remaining for Messages.  So if a new one comes in while they are on a page, that number literally changes while they are on the page.

I assume this is with Ajax, and not straight forward.  I don't know any DOM code or Javascript.  But would appreciate some help please.

Simon

I have a web site where users can gain points, when they use my site. For example, if the user spends $10.00 then the user will get 10 points.
In my web site there is a list of 10 retails (name). When the user clicks the link it will redirect to retailers website, where user can buy items.
How can I find out how much the user has spent on the retailer?
Thank you.

Can you suggest a better way to write this code (I didn't create it):

<body onload="getParameterByName('url')">

<a href="" id="urllink" >Click Here</a>

</body>

so, I don't have to change the <body> tag?