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From "Clute, Andrew" <Andrew.Cl...@osn.state.oh.us>
Subject Any plans for Reference filters?
Date Thu, 23 Sep 2004 15:50:05 GMT
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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