1.7 Testing
The aim of testing is to uncover errors in the design and implementation of the database, its structure, constraints and associated user and management support. Testing is usually considered to involve two main tasks – validation and verification. Without adequate testing users will have little confidence in their data processing.
Validation answers the question: has the right database been developed to meet the requirements? It attempts to confirm that the right database has been constructed, with the right characteristics to meet the specified requirements.
Verification answers the question: has the database design been implemented correctly? Verification ensures that the processing steps, constraints and other ‘programmed’ components of the database (security, backup, recovery, audit trails, etc.) have been correctly implemented and contain no errors in program logic or execution sequences.
Of course, testing does not just take place only after all the above development steps are complete. It is usually applied throughout the stages in the development processes and includes appropriate reviews to scrutinise the outputs of the development activities. The aim is to identify errors as soon as possible in the development life cycle.