except the logic of my database design..
are there any bugs in my design??
thanks..
http://i34.tinypic.com/11j3uxv.jpg

attributes
http://i38.tinypic.com/301hao4.jpg

i found at least one -- vehicle types don't have license numbers

Hi,

I would have linked the VehicleType with the Vehicle Table directly, not going trough the Licence table.
I would have linked as well the Driver to the Accident table.

I do not know if you really need the VehicleType, cause you have a Vehicle table as well. If you store more fields in VehicleType it makes sense, otherwise to store only one field, like car, bike, bus... it might be too much.
It might be overnormalization.

I hope it helps.
Now I've seen the attributes picture..., I'll have a look.


After seeing the fields picture I have even more questions.
What is the difference between PloiceName and PoliceStationName. From my point of view, if you don't have something like PoliceOfficerName instead of PoliceName, you could just merge the two tables.

The Licence table has engine capacity, wheels.... either you move them to the Vehicle or VehicleType tables or you double them in the Licence table(having the meaning MAX wheels, MAX engine capacity) and the Vehicle or VehicleType tables(having the meaning of actually how many wheels your vehicle has).

You don't have a foreign key in Driver for Restrictions and in Accident for Vehicle.