This was a lot of fun to play. In the proving ground, I would add a way for the user to be able to see the answer/what the expected input is. For example, when trying to find the max clearance level in the agency - SELECT MAX(CLEARANCE_LEVEL) FROM Agents; was not working, but there is no way to see what the input is that is expected.
Is your answer is not correct you can see the response from the db inside of the question.
I will add also a sample data so it will be easier to understand how the data looks like
played around a little bit and i loved it, i think if you added some advanced levels where you have to optimise a DLL/query to get past, it'd be sick.
Thanks for the feedback!
Great idea I will add it later on