For what it is worth: http://en.wikipedia.org/wiki/Temporal_database

A more extensive description/case study of bi-temporal database design: http://www.cs.arizona.edu/people/rts/tdbbook.pdf

This case study tried to be somewhat rigorous, but from what I recall the SQL did get complex and expensive pretty quickly. There are a few attempts to create products to mask the complexity as well:

http://www.timeconsult.com/Software/Software.html

For living in time and dealing with it regularly in a common sense sort of way, it is really rather challenging to manage effectively as data.