As a database theoretic concept I've been a big fan of time stamped based concurrency control protocols since I first learned about them. I've noticed they don't seem to be used much. Why is that? Or am I just wrong?
Edit: I mean timestamped data items with read and write time stamps and timestamped transactions with fixed timestamp order similar to what is described here: http://en.wikipedia.org/wiki/Timestamp-based_concurrency_control
