SQL Server trigger to preserve an existing value
Posted on 2014-09-26
I have a database field that stores a tracking number for shipments. Occasionally we send the order out in 2 shipments. When we process the 2nd shipment, our shipping software writes the new tracking number into the tracking field removing the tracking number that was already there.
I want to know the syntax to write a trigger for SQL Server that would evaluate the TrackingNumber1 field on update and, if there was already a tracking number in TrackingNumber1, it would capture it and move it to TrackingNumber2. The final result would be that I have both tracking numbers captured and available to me.
Can this be done and how?