Hi,
Can anyone suggest me how deep we can use and we should avoid the temptation of using Association in Hibernate in enterprise applns?

Say for ex, Product -> Purchase -> PurchaseDetails ->Settlements

In this chain of objects, is it advisable to implement association using Hibernate to this longer or limit it to just Purchase -> PurchaseDetails, as it is this which we may need to look for very often in report prepration etc? Or implement all links so that I could get settlements details by using
following code:

product.getPurchases().getPurchaseDetails(<xxx>).getSettlements()

Your kind reply is highly appreciated.

Regards,
Aru K

Or is it good design to implement association for every foreign-key relatioships????


For ex, teacher and examination relational tables, in whch examination has a field say Supervisor which refers the teacher tables ID. For this schenario, do I need to implement association using Teacher object in Examination or just go with having declaring a Long variable for teacher's ID in Examination object????

Which one is better option???

Sure.



Yes.



No.

One more question on the same subject.

Will it not affect the performance of the system (by taking account of large number of concurrent users) for the case of updating an Exam object in the case of having an association betn Exam and Teacher objects?

ie, even for mere update of teacher ID in Exam table, I need to load new Teacher Object and assign it to Exam's ID field and update Exam object.

As you know, somehow we would know teacher's ID before calling the function to update Exam object. Why should not we just directly supply the ID to Exam and update there.

If it is of Purchase ->PurchaseDetails, we could clearly see the strong relationship which would be enough to justify the Association, but I dont know if I m missing any important piece, why should I really care about association for the weaker case (in-frequently used one too)?

Thanks in advance for your reply!!!!

One more question on the same subject.

Will it not affect the performance of the system (by taking account of large number of concurrent users) for the case of updating an Exam object in the case of having an association betn Exam and Teacher objects?

ie, even for mere update of teacher ID in Exam table, I need to load new Teacher Object and assign it to Exam's ID field and update Exam object.

As you know, somehow we would know teacher's ID before calling the function to update Exam object. Why should not we just directly supply the ID to Exam and update there.

If it is of Purchase ->PurchaseDetails relation, where we could clearly see the strong relationship which would be enough to justify the Association, but I dont know if I m missing any important piece, why should I really care about association for the weaker case (in-frequently used one too)?

Thanks in advance for your reply!!!!

See the documentation on the differences between lazy and eager loading.



This depends on how many simultaneous users want to update Teachers and Exams .



My users have never noticed a time lag; my project manager has noticed time saved.



Eager vs. lazy loading.

Hi,
Thanks friend for your comments. They really helped a lot to clear off few important things.

Regards,
Aru K