While looking on the subject, I do recall something about old PostgreSQL versions having something like it... But I've always wondered how they deal with change

While looking on the subject, I do recall something about old PostgreSQL versions having something like it... But I've always wondered how they deal with changes to database schemas, types, etc. While googling I've found from this post: http://www.postgresql.org/message-id/Pine.GSO.4.64.0802031528120.7860@westnet.com http://www.postgresql.org/message-id/Pine.GSO.4.64.080203152... this free (?) book - Snodgrass/Jensen "Developing Time-Oriented Database Applications in SQL" - http://www.cs.arizona.edu/people/rts/tdbbook.pdf http://www.cs.arizona.edu/people/rts/tdbbook.pdf Haven't read it, so I'll spend some time through it. To me this is an interresting thing, since I would like to know whether I can do history tracking of game asssets for game development. E.g. often in our studio someone would like to compare data, how it was before this and what changed. We do have the mechanism, but they are not so ellegant.