在Rails中存储/检索历史数据的技术

I'm looking for some ideas about saving a snapshot of some (different) records at the time of an event, for example user getting a document from my application, so that this document can be regenerated later. What strategies do you reccomend? Should I use the same table as the table with current values or use a historical table? Do you know of any plugins that could help me with the task? Please share your thoughts and solutions.I'm looking for some ideas about saving a snaps