Perhaps this is a simple thing that my brain is having trouble with but I felt I should bounce this off a few of you here.
In a database I am building, I would like to ensure older Invoices and their line items do not change in price when my item information is updated. Say prices go up next year for a few of my items. I do not want the invoices from the past being updated with the new prices. Just new invoices created after the price change should reflect the new prices.
Along with the price i would add bill to and ship to addresses as fields you don't want to change. the solution is simple, don't show this info by relationship. create the field in the invoice and invoice line items tables and set the fields to lookup the data.