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Old 06-25-04, 12:42
Noah Noah is offline
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Question Help !!!! EERD Assignment ...

Dear Ladies & Gentlemen of the forum,
this is the first time I am doing database.
I have done up an ERD for school assignment, but certain aspects of the EERD was not covered in the textbook and I have nowhere else to turn to for help. Assignment deadline is nearing; would greatly appreciate any help. Thanks in advance.

The EER is as attached.
The question is, is it mandatory for the superclass, Employee, to participate in at least a relationship with other entities ?

My textbook says an entity cannot be modelled unrelated to any other entity as stated in the Conceptual Database Design Methodology.

However, because only the HirePointEmp will register HireRecord, I do not want the Employee entity to be associated.

Can any kind soul offer an advice ?
Thank you very much !
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File Type: jpg ERD4.jpg (20.6 KB, 880 views)
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Old 06-29-04, 13:40
Cipherlad Cipherlad is offline
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Ah, can you offer any other information about what all these tables are supposed to represent? What is HirepointEmp? What is DepotEmp? Why wouldn't they be related to Employee? We need more information to go on if we are to help you.
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