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From Jakob Braeuchi <jbraeu...@gmx.ch>
Subject Re: Any plans for Reference filters?
Date Thu, 23 Sep 2004 16:59:09 GMT
hi andrew,

you could use a query customizer to manipulate reference queries. i admit it's 
not as elegant as the filter but it's totally flexibel ;)

jakob

Clute, Andrew schrieb:
> I have run into a couple of scenarios where it would be extremely
> helpful to be able to add additional criteria to a reference descriptor.
>  
> For instance, you might have a Person object with a collection of
> Addresses on them. Address might have a property called "Primary". In
> your query, you might want to be able to qualify to use the primary
> address. The current way to do that is to keep a foreign key on your
> person table that links back to the primacy address object, and update
> that when your primacy address changes. So, you have both a property on
> your object, and a db column.
>  
> It would be nice if you could still have that reference descriptor for
> your person object for a Primary Address, but not maintain the foreign
> key in the db, just had a certain criteria to the descriptor that
> filters it to the appropriate one.
>  
> For instance:
>  
> <reference-descriptor
> 	name="primaryAddress"
> 	class-ref="pojo.Address"
> 	refresh="true"
> 	auto-retrieve="true"
> 	auto-update="false"
> 	auto-delete="false"
> 
> 	<foreignkey field-ref="personPK"/>
> 	<foreignkey-filter value="is_primary=1"/>
> </reference-descriptor>
> 
>  
> Does that make sense? Just curious if this has ever been discussed.
>  
> Thanks!
>  
> -Andrew
>  
> 
> 
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