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mustaccio
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Settle debate between Professor and Myself on interpreting Crow's Foot Notation in an ERD

I am taking an introduction to database objects course at college.

I am in disagreement with the professor over how to interpret the Crow's Foot Notation for Cardinality in an ERD diagram.

Example: Look at this image (one I pulled from lecture slides):

enter image description here

According to my interpretation, this indicates that:

  • A Supplier may have 0 or many Shipments
  • A Shipment may belong to only one Supplier
  • A Customer may have 0 or many Orders
  • An Order may belong to only one Customer

However, according to my instructor's interpretation, this shows that:

  • A Shipment may have 0 or many Suppliers
  • A Supplier can have only one Shipment
  • A Customer may have only one Order
  • An Order may have many customers

I have been unable to find any evidence to contract my own understanding of this... but, again, I'm just a student. Maybe I'm missing something? If I am, I'd like to figure out where I went wrong.