How to clear session of all users?

Question

I using php sessions in my project,i updated code:added some values to session.now i need to clear all existing sessions

ps.my OS is ubuntu 9.04

Answer 1

If there were a file included/required in all your files, you could put migration logic in there.

if (unset($_SESSION['myvar']) {
  $_SESSION['myvar'] = my_setup_myvar_func();
}

My main PHP application has such a file, but YMMV.