Double post, put answers here.

And what determines what is the previous value?  Some sample data...

Yea, if only it were that easy, just post your email address on a public forum and watch the offer roll in.  Wish I had thought of that, wonder how...

Just to let you know, the Data Vault design paradigm is database agnostic.  There are quite a few books out there that discuss the methodology and you may want to...