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Before going live, the newly developed database system should be thoroughly tested. This is achieved using carefully planned test strategies and realistic data so that the entire testing process is methodically and rigorously carried out. Note that in our definition of testing we have not used the commonly held view that testing is the process of demonstrating that faults are not present. In fact, testing cannot show the absence of faults; it can show only that software faults are present. If testing is conducted successfully, it will uncover errors in the application programs and possibly the database structure. As a secondary benefit, testing demonstrates that the database and the application programs appear to be working according to their specification and that performance requirements appear to be satisfied. In addition, metrics collected from the testing stage provides a measure of software reliability and software quality.
As with database design, the users of the new system should be involved in the testing process. The ideal situation for system testing is to have a test database on a separate hardware system, but often this is not available. If real data is to be used, it is essential to have backups taken in case of error.
Testing should also cover usability of the database system. Ideally, an evaluation should be conducted against a usability specification.
•Learnability - How long does it take a new user to become productive with the system?
•Performance - How well does the system response match the user’s work practice?
•Robustness - How tolerant is the system of user error?
•Recoverability - How good is the system at recovering from user errors?
•Adapatability - How closely is the system tied to a single model of work?
Some of these criteria may be evaluated in other stages of the lifecycle. After testing is complete, the database system is ready to be ‘signed off’ and handed over to the users.
kevowmuchiri answered the question on July 4, 2018 at 16:11
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