Stopping another data insert when user reloads page

[tidysi]

My PHP script inserts data into a mysql table that has been passed into it.

 

My question is, what is the general method by which to ensure that if a user reloads the screen, the same set of data doesn't get duplicated into the database?

 

For instance, I am inserting ticket data (its an ecommerce event system) into a mysql and really dont want duplicated entries if the user happens to press reload or back or whatever

 

Any ideas?

[Jessica]

After inserting it, use header() to go to a new page. If they refresh that page, it won't insert.