Problems getting a file back from MySQL database

Hi all,

I am developing a site where members can upload documents and attach them to articles which they publish.
I have been running through a tutorial about uploading files to a MySQL DB which can be seen @

http://www.php-mysql-tutorial.com/php-mysql-upload.php

I have managed to get as far as having the files upload to the database and i can see that they are there using the MySQL client, but my problem is trying to get the files back from the DB. I have tried implementing the code given in the tutorial, but it doesn't seem to be working
Here's the code i am using to get the file - i have passed the id of the record using the URL, but when i run it through, the page just refreshes...