Please please help

[David.Poundall]

Nice one namaroller. I was amazed to see so much interdependancy in the database. A question for you If I may. In what way are relationships within the database usefull as far as the application is concerned. Are they seen as hard coded inner joins at the SQL level?

[nemaroller]

Relationships in the database are firstly important for the integrity of the database itself - you have to visualize and enforce these even if you never connected an application to it. I enforced a few cascading changes and deletes too(looking back this morning, there should have been a cascading update rule between patients and the appt table, and the doctor and appointment table, but oh well )

As far as the application though - if you send a sql statement to delete an appointment, then all details of that appointment should be removed - this includes any ailments the patient described over the phone before the appointment because these were not verified in person.

End result, once you delete the appointment, any related records will also get deleted by the database automatically, so the application does not have to look for related records manually. (So a sql statement from an application 'Delete from Appointment where patientno=12 and apptdate=12/12/2004' will remove the appointment AND any entries from the ailments table, because of its relationship. You would not have to issue another command 'Delete From Ailments Where fkAppointmentNo = pkAppointmentNo Inner Join On Appointment....

Or, deleting a patient because they became deceased, you may want to remove any of their patient history-so all appointments and his related ailments will be removed)

Since you brought it up though, they would require an inner join to retrieve the ailments to compose a patient history (since they would have to first find all appointments for a particular patient, and inner join those on any ailments with a matching appointment id)

I wonder how far they got...

[David.Poundall]

I was wondering that also, but given that they only joined up to sort out this project at such a late stage they won't be VB die hards so chances are they won't be back.

[dglienna]

prolly turned something in, even if it wasn't right. teachers don't try to debug things, and like to give partial credit to things that they recognize as being correct. maybe they were able to slide through. i don't think that they finished it, though.