Every change has the potential to cause problems. Three common problems are:
- The change did not fix the problem for which it was intended.
- The change fixed the problem but caused others.
- At a future date, the change is noticed and nobody can figure out why it was made or by whom.
In all three cases the prevention is to track every change. Tracking entails recording:
- The original request for change. This might be a customer's request for a new feature, a customer's complaint about a malfunction, a developer's detection of a problem, or a developer's desire to add a new feature.
- The approval process used to approve the change (who, when, why, in what release).
- The changes to all intermediate products (who, what, when).
- Appropriate cross-references among the change request, change approval, and changes themselves.
Such an audit trail enables you to easily back out, redo, and/or understand changes.
Reference:
Bersoff, E., Henderson, and Siegel, Software Configuration Management, Englewood Cliffs, NJ: Prentice Hall, 1980.
