title: What is the right way to store paired logs?
body: <p>I have cycle conains 2 events which I want to log - take and return events. For now, I log any event I have fetched, take event triggered - creating new log with relations(user_id and etc), data and take type of event, if return event triggered - creating new log with relations (user_id and etc), data and return type of event. But when I need to fetch open cycles (without return type event) of user or closed cycles (there are take and return types logs exists for user and other relations) I don't know how to compute it. Is there the best way to architect such a logging?</p>