Hi I am doing an assignment on ER modelling and there is a part that I’m stuck on, here is an extract:
Patient is a person who is either admitted to the hospital or is registered in an outpatient program. Each patient has a patient number (ID), name, dob, and tele. Resident patients have a Date Admitted. Each outpatient is scheduled for zero or more return visits, which have data and comments. Each time a patient is admitted to the hospital or registered as an outpatient, they receive a new patient number.
I can’t do the last section bolded. I have attempted the question: http://tinypic.com/r/358dus9/4
Also if anyone can check if I’ve done it correctly, would be highly appreciated thanks!
Sometimes assignments also contain “information” that is pretty much immaterial.
The purpose is precisely to learn to filter out the ‘real’ information from the noise.
(With the caveat that there are dozens and dozens of ER dialects, and each has its own peculiarities,) ER does not have a way to express the information that “attribute x in entity y is to be autogenerated by the system.”. For this reason, and as far as the actual ER modeling is concerned, your bold phrase is just noise.