form cache problem

[Anon]

I create a form to get data from visitor.
after visitor submitted the data, i will
redirect them to a "Succcess page". But
the problem occur if the visitor click
refresh after they submitted the data, the
same dupplicated data is insert again to
database. how to solve it ?

I already tried metatags no cache, but still
cannot solve it.

[Anon]

work around is to have a form page, date update page, and success page. The users submit the data to the update page ("please wait while we update the database... etc") which has the GET & POST vars (use POST) then redirects the user to the success page (meta refresh = 0, or javascript document.location = submit_page). Since no vars were passed, refreshing the submit page shouldn't be a problem. the user should never really see the data update page and if they did the data wasn't updated so its fine to refresh.

another thing is to tie the users session with the database (using cookies, ip, etc) and notify the user that the page was submitted twice.

[Anon]

Oh, If the user press back button and try to refresh, database insertion occurs twice or more.