Hi everyone I have just started a course on database design and im having some troubling understanding just exactly what tables must be broken down at each DFD.
My problem is a company that has employees and a fleet of cars, the cars can be hired many times, and can be serviced many times but auctioned only once.
I had my unnormalised data as so:
Department Name Car Reg No
mileage Hire No
Mileage After Service No
Service Cost Auction No
At my First Form I had the tables sepaerated into 5 different tables,
The EMPLOYEE table has a one to many relationship with CARS and HIRES
The CARS table has a one to many relationship with the HIRES table
The CARS table has a one to many relationship with the SERVICE table
The CARS table has a one to one relationship with the AUCTION table
Is this breaking it down too much?