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From Jakob Braeuchi <jbraeu...@gmx.ch>
Subject Re: Any plans for Reference filters?
Date Thu, 23 Sep 2004 19:20:41 GMT
hi andrew,

the query customizer gets the parent object and the query (by criteria), so it's 
up to the customizer to modify the query. the query is processed as any other query.

jakob

Clute, Andrew schrieb:

> Yeah, looking at the code that is used for the query customizer on
> Collections, I would assume it would be real straight forward to add
> that to references as well.
> 
> Now a quick question about how QC's work.
> 
> Assume my scenario of Person with addresses collection, and the need for
> a 'filtered' Primary Address, property named 'primaryAddress'. If I did
> something like this:
> 
> Sc.addEqualTo("person.primaryAddress.zipcode","90210");
> 
> Would it be smart enough to allow the customizer to add it's filtereing
> on the JOIN query? Does it work that way for Collections right now?
> 
> 
> 
> -----Original Message-----
> From: Jakob Braeuchi [mailto:jbraeuchi@gmx.ch] 
> Sent: Thursday, September 23, 2004 2:59 PM
> To: OJB Developers List
> Subject: Re: Any plans for Reference filters?
> 
> hi andrew,
> 
> got me ! you're right query customizer only works for collections but
> imo it should be possible for references as well. so we could have a
> single concept for filtering.
> 
> jakob
> 
> Clute, Andrew schrieb:
> 
> 
>>Can you put a query customizer on a reference descriptor? I thought 
>>they were only for collections!
>>
>>-Andrew
>>
>> 
>>
>>-----Original Message-----
>>From: Jakob Braeuchi [mailto:jbraeuchi@gmx.ch]
>>Sent: Thursday, September 23, 2004 12:59 PM
>>To: OJB Developers List
>>Subject: Re: Any plans for Reference filters?
>>
>>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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>>>
>>
>>
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>>
>>
>>
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> 
> 
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