hi, in my web app the database has a blob(an xml file). The user is allowed to change the blob through a web interface. I take the blob show it in a html form, then the user can change some values and save it back. So the user submit request has a db save.
For some tracking purpose I want to store the previous and current state of the blob saved. So just before doing the save take the previous state from db and save current+previous state in another db table. But since all this is happening in the user request, this will slow down the response.
What is the best way to track changes so that the user response is not slowed?