Chapter 9: Support and Ch-Ch-Changes

Overview

Supporting a deployed application is not exactly glamorous work, but it is a task most developers face at some point in the development life cycle. No software is perfect. No software is really ever complete. At some point, if you are lucky enough to have your customers trust you with new ideas for an existing application, they might call you in to make changes to their program. This situation requires some special consideration when deploying the update to the production environment.

Not many developers like to get a phone call from a client that starts out with: ‚“I was running this feature and got an error dialog displaying error 1001, and I have to get my job done in the next hour so I can leave for the day. How soon can you fix your problem? ‚½ There is nothing like an irritated client on the other end of a phone call to add to a stress-filled day.

Tables are corrupted by power outages or users who decide to turn the machine off because the process is taking longer than ten seconds. More problems are revealed when users perform unspeakable and unexpected operations with your creations. The Fox Team has worked hard to fix many of the C5 errors they track down based on developer and internal testing bug reports , but these errors still seem to pop up when you least expect them and this adds to the challenges of supporting customers. Then there are the logic errors you include, often revealed at the worst possible time. The software we create today is more complex than the software we created just a few years ago, and the issues that surface are more difficult to support as well.

Implementing a new system has its own challenges, but implementing an update (new functionality, a bug fix, or both) can be more challenging for different reasons. How do you get the new files on the target computer with minimal interruptions to the users? How do you update existing files? Exactly what files are distributed with the release and what files do you make sure not to distribute? Once you figure out what to distribute, what is the process to deploy the changes? Is this a minor upgrade or a major upgrade? Does it matter?

This chapter addresses many of the issues you face when supporting and/or upgrading an existing application, and provides some solutions or approaches to solving the issues you might encounter.