Re: Openejb-jar and EJB 2.1 CMR Many-Many Example

[David Carew]

Here's a simplified version of the DB schema I used for a many to many
relationship between  CMP Entity beans called Account and Customer

create table customer
(
 customerid integer not null,
 title character(3) not null,
 firstname varchar(30) not null,
 lastname  varchar(30) not null,
 pin character(4) not null,
 primary key (customerid)
);


create table account
(
  accid character(11) not null,
  balance decimal(8,2) not null,
  interest decimal(5,3),
  type varchar(60) not null,
  primary key(accid)
);


create table custacct
(
  customerid integer not null,
  accid character(11) not null,
  primary key(customerid, accid),
  foreign key(customerid) references customer ON DELETE RESTRICT,
  foreign key(accid) references account ON DELETE RESTRICT
);


Here's the corresponding snippet from my openejb-jar.xml file

 <relationships>

               <ejb-relation>
                 <ejb-relation-name>Accounts-Customers</ejb-relation-name>
                  <many-to-many-table-name>
                        custacct
                  </many-to-many-table-name>


                  <ejb-relationship-role>
                     <relationship-role-source>
                        <ejb-name>Account</ejb-name>
                      </relationship-role-source>
                      <cmr-field>
                        <cmr-field-name>customers</cmr-field-name>
                      </cmr-field>
                      <role-mapping>
                      <cmr-field-mapping>
                      <key-column>accid</key-column>
                       <foreign-key-column>accid</foreign-key-column>
                      </cmr-field-mapping>
                    </role-mapping>
                 </ejb-relationship-role>

                  <ejb-relationship-role>
                   <relationship-role-source>
                      <ejb-name>Customer</ejb-name>
                   </relationship-role-source>
                   <cmr-field>
                      <cmr-field-name>accounts</cmr-field-name>
                    </cmr-field>
                   <role-mapping>
                      <cmr-field-mapping>
                             <key-column>customerid</key-column>
                       <foreign-key-column>customerid</foreign-key-column>
                      </cmr-field-mapping>
                      </role-mapping>
                    </ejb-relationship-role>
                </ejb-relation>

        </relationships>

On 4/20/07, Mark Aufdencamp <[EMAIL PROTECTED]> wrote:

Hi All,

 I'm continuing my studies and have successfully deployed CMP Entity Beans
with some rudimentary QL.  I'm now working on come container manged
relationships (CMR).  I can't seem to find much documentation on the
appropriate mapping of the ejb-jar relationships to the openejb-jar
definitions.  Can someone provide some direction to documentation on the
openejb-jar mappings.  In particulare, I'm working on a Many-To-Many
relationship.  I have a 3rd NF Table structure and the Entity Beans, just
need that last bit of info on the openejb-jar mappings.

Thanks,

Mark Aufdencamp
[EMAIL PROTECTED]