A developer came to me for guidance with a trouble ticket. He asked if we ever delete data from the database. Apparently the customer had some evidence that some data had disappeared. This seemed very strange.I told my colleague that there are some scenarios where we do delete data:
- if there is an error when loading data, we delete the partially loaded data
- at the end of the year we delete out the old records
None of these scenarios seemed to cover the case that the customer was experiencing. I agreed to take a quick look at the facts. The customer had printed out evidence that the data was there last month. So I checked our audit data in the Production environment. Sure enough the data was loaded and worked with our application. Then I detected a significant clue. The date when the data was loaded was the day when we do our system startup testing. I realized that this would have been test data that gets loaded and then deleted before the Production system goes live.
Once we realized the situation, it was easy to work this trouble ticket. But being able to correlate that specific date with the load testing activities requires insider knowledge of our system. An outsider would have never deduced that this was the case. This goes to show you that sometimes a little key knowledge can go a long way in problem resolution.
