insert / update problem

[Anon]

Im doing a shopping cart and im having some problems with insert and update because ..
A person fills a Form with his name, address, etc...
Then the person presses Submit, and passes to the next page the variables in the form, and those variables get into mySQL database with an INSERT, but if the person presses the Back button (of explorer) and sends the form again, i have to do an UPDATE and not an INSERT..
so i need to kwon how to do that in PHP ...

[Anon]

If you give them a session before they go into the form, then use that session to identify the transaction, you can do a "select COUNT(*) where sesion=".$session.";" and then if the result is greater than 0 use update with a where session=$session, again, or an insert if the count is 0.

benja wrote:

Im doing a shopping cart and im having some problems with insert and update because ..
A person fills a Form with his name, address, etc...
Then the person presses Submit, and passes to the next page the variables in the form, and those variables get into mySQL database with an INSERT, but if the person presses the Back button (of explorer) and sends the form again, i have to do an UPDATE and not an INSERT..
so i need to kwon how to do that in PHP ...

[Anon]

Im not using session because i dont know how to pass the session trough a secure server (ssl)(from http to https ), when i use sessions there i loose the session.

[Anon]

Yeah you'd have to add some logic on the receiving page to select out of the database to see if it was posted already. If it was posted, then do an update instead of insert.