title: Storing Updating Fact Table Data
body: <p>I'm looking for some advice on how to handle this scenario. I have a fact table for Purchase Orders Lines, each line has a Planned Delivery Date. As the purchasing buyers work with vendors, the planned delivery date is updated in the source system. The delivery date can change multiple times (backorders etc.).</p>
  <p>I'm trying to figure out the best way to store the delivery dates in the data warehouse. I could update the line with the latest delivery date, however, we also need to be able to store the history of the changes to planned delivery dates.</p>
  <p>My other thought was to build a separate table for delivery dates.</p>
  <p>Any thoughts would be appreciated.</p>