Re: EJB 2.1 CMR Bi-Directional with Compound Key

[Gianny Damour <gi...@optusnet.com.au>]

Hi Mark,

I had a look to the openejb-jar DD and I think you need to drop the  
<foreign-key-column-on-source/> element from the Committee- 
CommitteeMembers relation. This optional element means that the  
foreign key columns declared in the following <cmr-field-mapping>  
elements are defined by the CMP declared by <relationship-role-source>.

So, this should work:

<ejb-relation>
   <ejb-relation-name>Committee-CommitteeMembers</ejb-relation-name>
   <ejb-relationship-role>
     <ejb-relationship-role-name>Committee-has-many-CommitteeMembers</ 
ejb-relationship-role-name>
     <relationship-role-source>
       <ejb-name>CommitteeEntity</ejb-name>
     </relationship-role-source>
     <cmr-field>
       <cmr-field-name>committeeMembers</cmr-field-name>
     </cmr-field>
     <role-mapping>
       <cmr-field-mapping>
         <key-column>CommitteeId</key-column>
         <foreign-key-column>CommitteeId</foreign-key-column>
       </cmr-field-mapping>
     </role-mapping>
   </ejb-relationship-role>
</ejb-relation>

Also, you do not need to declare both sides of a relationship: the  
above is enough to declare the CMR mapping for the Committee- 
CommitteeMembers relation.

BTW, I strongly recommend you to upgrade to OpenEJB3: this should be  
a seamless migration from a CMP perspective as the OpenEJB guys have  
done a fantastic work at writing an OpenEJB2 schema converter.

Thanks,
Gianny

On 30/05/2007, at 1:07 AM, Mark Aufdencamp wrote:

> I could really use some help on this!  I have a two Entity beans  
> with a bi-directional relationship, committees and  
> committee_members.  Committees has a single field primary key of  
> committeeId.  Committee_members has a compound primary key of  
> CommitteeId+UserId.  A Foreign Key constraint has been defined for  
> the committee_members table based on the committeeId.  I can't seem  
> to get this to deploy and believe it's my openejb-jar.xml  
> deployment descriptor in the <relationship> section.  I've looked  
> at examples from JBoss and Sun, so I'm fairly certain my ejb- 
> jar.xml is correct.
>
> Does anyone have a working example of a bi-directional relatioship  
> where the many table has a compound key that I can take a look at?
>
> Where can I find documentation on how OpenEJB and TranQL interact  
> to create the O/R map?
>
> This knowledge are really seems to be lacking documentation in  
> Geronimo.  I'd really like to draw some pretty pictures of tables  
> and beans with the seven different relationship types defined for  
> EJB 2.1.  This would be good preliminary work for documenting EJB  
> 3.0 examples.  Please help me learn, so I can contribute:)
>
> TIA,
> Mark Aufdencamp
> Mark@Aufdencamp.com