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ERD Diagram Many-to-Many Relationship with Restriction
Hello, I have some homework that I can't seem to figure out. I've tried everything I can think of but I don't think it's right. Here is the problem:
Donors only have a relationship with an Item entity type. A donor must have donated one or more items, and an item may have no donors, one or more donors.
What I have is
It's an obvious many to many relationship and I need an intersection entity but since it states that donors can only have a relationship with the item entity, what do I do?
I was thinking of having DONORITEM that has both primary keys of the respective entities but it just seems wrong with that restriction.
If your intersection entity has only 2 columns (one for donor, the other for item) you should be fine.
Why might this not work for you?
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