I've got a situation with minibus repair database design, where it looks like in the Repair table I could do with a 3-composite primary key: jobID from the JobType table (types of maintenance with price and time),
mechanicID (Mechanic table), minibusID(minibus table). This way, I've got type of job performed on the minibus, who fixed the bus, and which one it was. Besides that I intend to add to the Repair table dates (start and finish), and price.
Is it ok to make all the 3 components primary key, or is it better to add another column such as repairID? Or maybe I should find other way to design it?