I have noticed that if the user clicks the back button (warning box opens about re-posted data) the data is inserted again into mysql.
I need to avoid this happening. The page is posted to itself and stops when the uploaded data is succesfully loaded into mysql, it then offers a number of links to the user, clicking the back button is one I want to avoid. I have thought of using HTTP_REFERRER to check the page it has come from and header("Cache-Control: no-cache, must-revalidate"); to clear the cache.
I would like to know what an expert would do