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Re: Prefetching relationship issue
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Re: Prefetching relationship issue


  • Subject: Re: Prefetching relationship issue
  • From: Lachlan Deck <email@hidden>
  • Date: Wed, 16 Jul 2008 09:41:46 +1000

On 16/07/2008, at 9:05 AM, Federico Hernandez wrote:

- I'm using vertical inheritance.
- Yes, Entity A maps to a table ENTITY_A, but it is abstract, so its table
is empty.

That doesn't make sense. It either maps to a table or it doesn't - regardless of whether it's abstract. The flag isAbstract simply says to the runtime 'cannot be instantiated' (same as public abstract class...) which is a separate concept to whether or not it has an external table or data.


What you've described is horizontal inheritance where the super entity has not external table mapped and therefore must be abstract.

- No, Entity B maps to its own table ENTITY_B.

- Because I'm using VI, I didn't use a restricting qualifier

Horizontal inheritance can't have restricting qualifiers AFAIK (only ST or VI can).


I don't know that you can have a many-to-many table with HI.

If you do indeed have VI - then I suggest using a restricting qualifier.
I use an attribute entityType in my parent entity. You can populate it during awakeFromInsertion and define the restricting qualifier relevant in the model for each subclass.


with regards,
--

Lachlan Deck

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