You're right that the user may resubmit a lot of values, but if the id has to be generated by the server in order to be valid, you can effectively enforce that the user is only allowed to insert data once, even when using low-tech user agents such as Lynx or WWW::Mechanize.

Using JavaScript to disable a button will only work on well-behaved JavaScript-enabled browsers, and thus looks like a nice solution to the wrong problem.