Last month, I summarized a July 2006 survey exploring the current state of data management within IT organizations. The area of greatest concern revealed by this survey is the abysmal level of database testing: 96 percent of organizations considered data to be a corporate asset and 64 percent implemented mission-critical functionality within the database, yet only 40 percent had tests to validate the data and 46 percent the functionality. Worse yet, the survey revealed a lack of recognition that we need to be doing database testing at allonly 32 percent of organizations not testing for data quality, and 39 percent of organizations not testing database functionality realized that they needed to do so. Clearly something is amiss.
There are three fundamental reasons why you need to develop a comprehensive testing strategy for your RDBMS:
- First, data is an important corporate asset and you must ensure that its quality is sufficient for your needs.
- Second, because it is common to implement functionality within a database in the form of stored procedures or stored functions, you must validate this functionality.
- Third, a regression test suite for your database enables modern evolutionary development practices such as database refactoring. Because all modern software development processes are evolutionary in nature, I believe that data professionals must adopt evolutionary techniques such as regression testing and refactoring.