I can think of two very annoying places where state gets kept that is out of your control:

  1. You're using mod_perl and somewhere you keep state in variables. This might be the proverbial global $counter variable or something more hidden. Usually contributing to the confusion is if you have multiple Apache processes (and mod_perl interpreter instances) where each process keeps its own state. The approach to the solution is to start Apache in the single-worker mode and to try to reproduce the failure there.
  2. Browser caching is the second nasty thing that shows you results that you don't expect. I usually use wget or curl or LWP::Simple to get at the raw data without any browser caching getting in the way.

As a general approach, I would add the appropriate indices on the database side, making the number column unique to prevent duplicate entries even if the application logic fails.

In reply to Re: Weird CGI behaviour on different Browsers - Apache by Corion
in thread Weird CGI behaviour on different Browsers - Apache by Yaerox

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