There is a possibility to mark a context as "prevention" when creating references between institutions. Can someone explain me in simple terms what is the difference between plain reference and prevention? Definitions and interpretations that I found so far have not worked for me.
context: A reference is a plain "ABC knows " is the relationship. Different references do not affect each other. It can be seen that B & B can know. Therefore, if you have A, you can go to B. on B. If you remove the context, A, B and C. are still present, they just do not know each other.
Prevention: There is a prevention "A is B" type relationship. Generally used for lists, e.g. "A has multiple b" echo / emf can then display atomic orders on such collections, such as to control all objects from one to the other. It can also apply constraints, such as the minimum amount of the contained items or the maximum items involved, or to ensure that the object is not included in any other prevention.
Example:
Assume that you have an object named shoppingcart and an object named customer and < Code> OrderedProducts is the prevention. The context of a directed product is a product .
What does this model tell you?
- You can assign a shopper to a customer if you remove the customer from shoppingcart, the client object will be present itself (for example in the database)
- Ordered To get the product items available, a shopping cart is required. If you remove one from shoppingcart, then this entity will end.
- Each ordered product database has a reference to an existing product. If you remove one of the products ordered from shopping kert, the product will still be present in the database - the order of that product has just gone for that specific customer
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