Gary Varga (11/30/2015)
Eric M Russell (11/30/2015)
...For example, a shopping cart for an ecommerce website is not the same thing as a purchase order for accounting, and only when the customer actually enters their credit card information and clicks the submit button does it become a set of golden records worth managing permanently...In the example when saving an actual order it doesn't have to be to a database. This could be implemented using transaction message queues thus further decoupling the back office from the online presence to ensure that both systems can remain performant without disturbing each other.
Amazon appears to do this. The orders don't go into a live db, or the same db I query as an "order" in real time. There are delays at times. Usually seconds/minutes, but delays, yet AMZN seems to manage that well.