Database design/layout

Question

I have an objective to record and store test data. A secondary objective is to track the progress of the test programme (it is a large programme). So I want to use MySQL (not Access or DOORS) to create a database that will store this data.

I have created an initial database design with the following extract

Attributes:

• EvidenceRequirement: Id, Title, Description;
• EvidenceSource: Id, Name;
• TestType: EvidenceSource.Name, Title, Description;
• TargetTestPoint: Id, ???

Now the question marks above highlight my problem. Each Test type gathers different data and so the content of the TargetTestPoints will also vary (e.g. some test points will require a mass (kg) attribute, some won't). So the above is not sufficient to store the data.

The only alternative design idea I have thought of, is to create a new table for each test type which stores this content. I haven't got an issue with having too many tables but to me it is not very elegant as every entry in these new tables will link to the same evidence requirement. This just seems wrong to me?

So the question is, has anyone got a more elegant solution?

NOTE: The design is an initial attempt so it has not been properly normalised and there may be other alterations. Also, this is an extract of a bigger database design. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ I thought I'd give more of a description to aid comprehension (as I may be being a bit vague):

• Evidence Requirements: This will be the requirement that is driving the testing. Example: The aircraft will demonstrate it has a positive longitudinal static stability.
• Evidence Source: This is the test method that will satisfy the requirement. So for my example it would have an entry of "Longitudinal Static stability testing"
• Test Type: More information on the test method (such has what, why and how). The example here would include the detail for conducting LSS testing.
• TargetTestPoint: These are the configuration details for the test point. So for our example, what is the airspeed, pressure altitude, a/c mass, a/c CG etc...

So if I wanted to add new evidence source for a different evidence requirement (say add manouvre stability or pressure error corrections (PEC)), the data for these in the target testPoints will be different (e.g. a/c mass and a/c CG are irrelevant to PEC)

Anyway I hope that helps.