Redirect to external URL

How do I set up one of those redirect URLs that redirect the user to an external URL, for example:

/clickthrough.php?businessId=4805

Also if I did this would this be classed as a backlink for that site in terms of SEO?

 

well to do that you just create a script that processes the $_GET data (the $businessid=4805) bit... so i'd do

$id = $_GET['businessid'];

and then something like using a MySQL query to select the row from a database of links... then just use the header function... so basically:

$id = $_GET['businessid'];

$link = "Select ".$id." FROM links";

then sort that use a mysql_query to get the link.

following it with

header("location: ".$whatevervariablelinkisstoredin."");

that's my glance over of it xD

 

Perhaps $id = intval($_GET['businessid']); just to be on the safe side.

 

Thanks for the responses guys.

Danltn - what difference would the intval make?

 

Stop MySQL injection attacks.

Also do you not mean SELECT url FROM table WHERE id = $id LIMIT 1;

 

Yeah... i was just giving a basic ideaology of it for him

 

Disalow the php redirect page from the robots.txt if you wish to not have a link from your site counted as a backlink to the linking site. Everything else has been mentioned above.