Entity-Relationship Diagrams: Minimum cardinalities: Order processing example
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- เผยแพร่เมื่อ 26 ม.ค. 2017
- This video gives a simple example on how minimum cardinality works in an order processing ERD
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its nice man keep it up
Thanks. Saved my life
Was just about to say the same thing😆 Thanks @Mark!
thanks a lot your video helped me a lot
great video, thanks
What if for example the min must be say 5 and the max can be 20? Ex: A class must have a min of 5 Students to start and no more (max) of 20 Students? How would one show that in the diagram?
How to ensure or implement minimum cardinality while building schema objects in DB
But an order can have at least one product to be created, and can have more than one product as well.
Yes, that would be another record with the same order number. The relationship here is corresponding to each record. Hence, the optionality