[hibernate-dev] dynamic entities

[Max Rydahl Andersen]

You got two replies already and you still want to argue if you have our  
ears.
Either speak up or don't ;)

As I said my background is medical systems and I disagreed with the level  
of dynamacity you referring to...
you take it from there.

/max

> sorry I don't see how Christian answer was serious brushing me off with  
> few classes to insert into EAV. granted the way I landed this on you  
> deserves such a reply but can we skip to the serious phase.
> well spotted that I am talking about a deep level of dynamic. Serveral  
> domains not just the medical field have thousands of objects with  
> subsets needed in different circumstances. some domains use domain  
> specific languages with runtimes to interpret content. There are many  
> reasons why you can't map objects to tables at design time. There are  
> many other reasons why you can't have a static domain model. I am not  
> here to argue the problem but explore the solution with you.
> do I have your ears?
>
> Max Rydahl Andersen <max.andersen at redhat.com> wrote:
> Christians answer was actually serious ;)
>
> My background is medical systems and both HL7, GEPJ and the european
> DH
> has a great deal of genericity because the medical domain has it...but I
> don't see how it requires
> the level of dynamicity you are referring too.
>
> /max
>
>> very funny. I had similar skepticism  until I worked in such domain. I
>> understand the issues surrounding such a model, I spent 15 years working
>> for Oracle. implementing it is not that trivial. there is a real need
>> and I explain the details if I have more serious replies.
>>
>> Christian Bauer  wrote:
>> On Apr 30, 2007, at 9:48 PM, Iyad Elian wrote:
>>
>>> alternative persistence model common in some domains like the medical
>>> domain. how do I go about it?
>>
>> So data consistency and integrity is not important in the medical
>> domain and the EAV stuff is used as the main model for data
>> management? I can't believe that. EAV is just a synonym for "I don't
>> like to think about data management and schema evolution, therefore
>> let me break it right away in the design phase." Of course, it has
>> its uses but it's rare to see it applied properly.
>>
>> Implementing an EAV pattern on top of Hibernate is trivial. Attached
>> some source you may use if you promise never to design a system with
>> this that runs my pacemaker.
>>
>>
>>
>> ---------------------------------
>> Ahhh...imagining that irresistible "new car" smell?
>>  Check outnew cars at Yahoo! Autos.
>
>
>



-- 
--
Max Rydahl Andersen
callto://max.rydahl.andersen

Hibernate
max at hibernate.org
http://hibernate.org

JBoss a division of Red Hat
max.andersen at jboss.com