1) Log-In as a use case: NOT Recommended
Reason: The different role implies restriction for functionality. The
Log-In is just the result of this. So, it is not a stand alone task. If
the Log-In involves some substantial steps, then in that case it qualifies
as UC.

2) Log-In as use case and included in most other Use Case : WRONG
Reason: That would mean you need to login for every task (regardless of
whether you logged in or not), which is incorrect.

3) Deletion/Modification of Patient Record/Consultation Record as extra
feature: NOT Recommended
Reason: Extra feature must add value to the system. The above are not
included in the spec because they are infrequently used in the first place
:).
Good example: Adding allergy info to patient and alert doctor when
prescription is given. Please keep this example to youselve to judge valid
extra feature :). It is proposed by one of my team.

4) Some "exotic" :) existing classes to use for storage: DEPENDS
Reason: As we disallows DBMS, some of them will try to use other built-in
class to make their life easier, e.g. JTable, XML-related classes etc. As
long as the class DOES NOT help them to implement the searching
requirements, then its alright, i.e. these classes should just be used to
store/restore info and NOTHING else. :)

5) There are books that recommend a domain model that:
Capture everything in the problem domain, irregardless of whether they are
useful in the system later on. 
------------ A

The other version of domain is:

Capture only entity in the problem domain that is going to be in the
system in some way (maybe modified/refined later, but they are essential).
------------ B

During lecture + tutorial, we are following strictly version B (also known
as system domain model).  Version A is known as Exploraty domain model,
which is not covered nor followed in the course :).

Hence, I feel that it is only correct to follow version B, which is the
stand we are taking for so long now.

So, using version B:

Doctor and Nurse _can_ be there, if they use this information for access
control (i.e. login etc).

Patient should be there, but not as both an external user AND entity (i.e.
no patient and patient record at the same time).


Also, the association can be determined in the same way:

PatientRecord ----- ConsultationRecord (needed)
Nurse -------- PatientRecord (not needed, as this info is not useful).