While this is an upgrade question I am hoping a quiz expert can lend a hand.
I have read the documentation stating that if you have a lot of question attempts stored then it might be a good idea to archive/delete the old attempts. We have 2.7 million rows in question_sessions and 6.5 million rows in question_states. I am fine with getting rid of all the old quiz attempts, but I don't know what to delete if I wanted to get rid of all question attempts more than 1 year old. If I delete a bunch of question_sessions and question_states do I need to also remove info from another table to prevent those deleted rows from being referenced?