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From Andy Jefferson <a...@jpox.org>
Subject Re: Inheritance proposal
Date Tue, 09 Aug 2005 14:14:43 GMT
Hi Michael(s),

Not fully read your proposal, so can't comment on the rest ...

> - Does JDO require a inheritance element for classes in an inheritance
> hierarchy? If not, is there a default? The same questions apply to the
> strategy attribute inside of the inheritance element.

You don't need to specify it. The default (strategy) is
* If the class has no persistence capable superclass, use "new-table"
* If the class has a persistence capable superclass, use "superclass-table"

> - Can I figure out whether inherited fields are mapped to the superclass
> or subclass table by just looking at the inheritance strategy? I think
> the answer is no, correct?

Yes you can. The inheritance always has a strategy (see default above), so you 
know where the field will be persisted. I *believe* that the 
<inheritance><join> is only for specifying the names of the primary key 
columns in app identity cases. Perhaps there's some other use for it that I 
don't know of ?


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