I'm currently writing tests for a Data Registration system. In summary, a data provider will supply a daily update file that will be processed by the registration system and if they pass the validation checks, the registration system will update the data it stores for those records contained in the update file.
I've been given a list of 85 different update scenarios - that is 85 different ways the data can be updated in the database, which consists of a series of related tables. Having had a look at these scenarios, I don't think that it would be necessary to test all 85 scenarios. The system is however implemented on large scale and is a nationwide system. For confidentiality, I cannot reveal details about the system, so lets take an example of a Police motoring system. So lets say, for example, the system accepts a daily update file from Vehicle Insurance companies containing changes to their records for details of the cars and owners they cover. Lets say that their are 85 different forms of update they can send - So 85 different update scenarios. An example scenario may be a change of Address of owner. Another scenario may be Change of Address and car of owner. A third scenario may be a change of name of owner and license type of owner, etc... The daily update file may contain an update for a single record i.e a driver or thousands. From what I have seen, these update scenarios seem to be categorised - 20 scenarios related to updating owner details, 25 scenarios relating to adding new vehicle owner, etc....
So my question is how would I write tests for these update scenarios without having to write tests for all 85? Is it a simple case of choosing a subset of scenarios from each category and write test for those? So for example, In the 'update owner details' category, I could have one test that updates all the owners details using the assumption that if that works, then a test for updating the owners name only, will work.
The testing environment is manual.
Your input is appreciated.