Advice about design required

Question

Hello all,
I am new with OA Framework development. I have read the Oracle tutorials, but I still have many questions about a best way to design the application. For example we have a fully customized module, kind of Mini MRP, which recommends purchase or sale back stocks of items between 10 different inventory organizations.
Each item has attributes which affect the stock level and reorder point, some of attributes defined on master organization level and others on specific inventory organization level. In addition the are table which contains on hand of item in each organization (mtl_onhand_qty) and table which contains history of usages of the item in each organization. Also item can have previous versions and planning done for whole family ( the item and all it's previous versions)
Now what I need to develop is a screen: user enters an item - and in left frame displayed the tree of family of item, in other frame there is a table of all 10 organizations when the columns are stock of the item in each org, usage of the item in each org,ROP etc.
My question is : how to design entity objects for application like this?
Should I create entity object for Item and another object for item in organization and another one stock of item in organization and for usage etc and to base view objects on those EO, or alternatively another approach - to create one huge view which will contain all the relevant data about the item in organzation ( stock,usage, attributes etc) and to base my EO and VO on this view? Please advice which approach is prefferable....
Sorry for long post :-)
Any help appreciated.
Thank you

Answer 1

I fully agree with what Tapash said, in case of external joins if EOs, even the code given in dev guide does not work....(Tapash correct me if I m wrong...! i remembered struggling with that code.... long time back, I m not sure of they have corrected it in 12i dev guide.) .
But the logic has to be understood that framework understand it to be a update operation instead of insert opeartion ..for the table which does not have the joining key record and joined with external join.
So this concept has to be implemented accordingly. I had scenarios where the query has to had external joins of EOs... so i made VOs based on sinle EOs and joined through VLs instead of going with external join of EOs in VO query, that worked fine.
--Mukul