So i am trying to create a db for a restaurant as a homework assignment.. However there is a spot that confuses me and involves the dish entity.
"Every dish must belong to a category (soup,appetizer,salad,main dish). The main dish must be either pasta,pizza,rice"
The problem is that pizza and pasta have unique attributes... So the question is do I encompass all of them with the rest of the dish attributes and nullify them when the dish is not pizza or pasta? Or do I form some kind of ISA entities? And in the second case, won't it complicate my db a lot by adding many entities?
Aucun commentaire:
Enregistrer un commentaire