For this test you will need a course with at least a student enrolled. Log is as admin and go to Site administration > Plugins > Activity modules > Assignment settings Check Enable timed assignments assign | enabletimelimit setting and save changes. Go to the course, turn edit mode on and click to add a assignment. On the assignment form, fill the fields Activity instructions , Aditional files , check Only show files during submission , enable Time limit set a time limit for this assignment and save. Have a look for that created assignment in the assign table and take note of the id field. On the more menu, select Overrides . Add a user override to s1 setting a different time limit and save. Log in as s1 go to the course and make a submission to that assignment. As admin, make a backup of that assignment. Once the backup is done restore that same backup, preferable in same course. View the assignment settings. Make sure the values of the fields above (Activity instructions, aditional files...) are restored. Go to the overrides page. Make sure the user override is restored with the time limit field value. In the database, query the assign table for the assign that was backed up and the one restored (should be the next id) Make sure values for the fields 'preventsubmissionnotingroup', 'activity', 'activityformat', 'timelimit' and 'submissionattachments' have been restored. Now query the assign_submission table for those ids (assignment = X) Make sure the value for the 'timestarted' field have been restored. Now query the assign_overrides table for those ids (assignid = X) Make sure the value for the 'timelimit' field have been restored. Note : If you decide to restore the assignment in a different course, make sure the same user (s1) is enrolled on that course otherwise you won't get any submissions or overrides.