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From Andy Jefferson <a...@jpox.org>
Subject Re: Issue 138: Names of optional features
Date Thu, 09 Feb 2006 11:23:41 GMT
Hi Craig,

> The problem with your approach is that your descriptions don't match the 
> semantics of the restrictions. The subclass-table metadata  
> attribute is used for cases of joined and non-joined tables, and the  
> restrictions are most likely on non-joined tables. Specifically, if  
> you have a concrete Person, abstract Employee, and concrete  
> FullTimeEmployee, you can map Employee fields to subclasses and map  
> to PERSON and FULLTIMEEMPLOYEE that either have a join relationship  
> or non-join relationship. I believe that JPOX supports subclass-table  
> but not NonJoinedTablePerConcreteClass.

* JPOX supports "superclass-table", "new-table", and "subclass-table" as an
inheritance strategy so you can have objects in a tree using those.
* JPOX doesn't support a class with a field that relates to an object of a type
using subclass-table strategy.
* JPOX supports classes with fields that relate to objects of a type using
superclass-table, or new-table.

e.g If you have Department with a list of Employees, with Department with an
employees field defined with element-type of Employee. JPOX supports Employee
uses inheritance strategy of new-table/superclass-table. It doesn't support that
relation where Employee uses subclass-table.

That is what I was trying to distinguish. As long as that is specifiable using
your categories then I'm happy.

> The names in the optional features list would be fully described in  
> Chapter 11 but I was looking for a shorthand description.

Excellent, then it's not an issue.


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