White box testing is the approach based upon logical check of the migration script. With the knowledge about the database source and receiver structure the team of QA engineers test completeness and correctness of the script. Still, to start white box migration testing the database should comply with the certain preconditions.
- Detailed script description (it should prevent the issues of incorrect data migration or the incompleteness)
- Structure of the source and the receiver
- Data Migration Mapping (set of migration rules written in any suitable format)
When the testers finally jump start the testing process, they get through the standard points:
- Check of the number of migrated registries
- The data are migrated to the appropriate place
- The data fullness
- Filling of the obligatory fields
- The proper source and receiver fields processing
- Accounting business logic changes
Along with these points of migration script check, testers apply the analysis of the SQL code. The approach covers in details the database structure, used data storage formats, migration requirements, analysis of substances, difference among them and their correct processing. The formats of fields and the migration script transformations are also of great importance.
The white box testing approach requires specified knowledge from a tester, unlike the black box approach.
Still, you rarely meet the applying purely the black box or the white box approach, often the complex approach is used. In the complex approach the QA engineers first check the logic of the migration script (white box approach), then they run functional tests (black box approach) on the application to check the migrated data.