I have 2 tables that are linked: Proforma Invoice and Items Ordered. For one
Proforma Invoice, there could be many items ordered. The challenge is that I
need to maintain some kind of revision when any of those information are
changed like additional items, change in color, change in delivery dates, etc
and they could be in any of those 2 tables.

Is there any way I can do a "snapshot" of the data and store that into
another table since changing the values in the fields means overwriting the
previous info? Or is anyone able to suggest a better way? Thanks.
ck