M:N relationship in CMP using 2 entity beans

[Aasheesh Lal]

I am trying to implement M:N relationship with 2 beans CourseBean and
StudentBean. The corresponding tables are course, student and enrol.
enrol is the join table with two columns each being FK to the PK in
course and student tables.
When running ejbc on the jar file, I get this error I've copied below:
PS: The columns in enrol are studentID and CallNumber. The code for
beans and descriptors follow the error message below.
I appreciate any help. I've spent a day trying to figure it. Thanks a
ton in advance.
~
ERROR: Error from ejbc: Error while reading
'META-INF/weblogic-cmp-rdbms-jar.xml'. The error was:
In relationship 'student-courses', role 'students-take-many-courses',
invalid column 'sID', a column-map element contains an invalid
key-column. The key-column is not defined in the related bean or it's
not recognized because of case mismatch.
In relationship 'student-courses', role 'courses-have-many-students',
invalid column 'courseCallNumber', a column-map element contains an
invalid key-column. The key-column is not defined in the related bean
or it's not recognized because of case mismatch.

 
Part of weblogic-cmp-rdbms-jar.xml
…….
  
  <weblogic-rdbms-relation>
    <relation-name>student-courses</relation-name>
    <table-name>enrol</table-name>
    <weblogic-relationship-role>
      <relationship-role-name>courses-have-many-students</relationship-role-name>
      <relationship-role-map>
        <column-map>
          <foreign-key-column>callNumber</foreign-key-column>
          <key-column>courseCallNumber</key-column>
        </column-map>
      </relationship-role-map>
      </weblogic-relationship-role>
    <weblogic-relationship-role>
      <relationship-role-name>students-take-many-courses</relationship-role-name>
      <relationship-role-map>
     
        <column-map>
          <foreign-key-column>studentID</foreign-key-column>
          <key-column>sID</key-column>
        </column-map>
      </relationship-role-map>
      </weblogic-relationship-role>
  </weblogic-rdbms-relation>
Part of ejb-jar.xml file
<ejb-relation>
      <ejb-relation-name>student-courses</ejb-relation-name>
      <ejb-relationship-role>
        <ejb-relationship-role-name>courses-have-many-students</ejb-relationship-role-name>
        <multiplicity>many</multiplicity>
                <relationship-role-source>
          <ejb-name>StudentBean</ejb-name>
        </relationship-role-source>
        <cmr-field>
          <cmr-field-name>courses</cmr-field-name>
          <cmr-field-type>java.util.Collection</cmr-field-type>
        </cmr-field>
    </ejb-relationship-role>
      <ejb-relationship-role>
        <ejb-relationship-role-name>students-take-many-courses</ejb-relationship-role-name>
        <multiplicity>many</multiplicity>
                <relationship-role-source>
          <ejb-name>CourseBean</ejb-name>
        </relationship-role-source>
        <cmr-field>
          <cmr-field-name>students</cmr-field-name>
          <cmr-field-type>java.util.Collection</cmr-field-type>
        </cmr-field>
      </ejb-relationship-role>
    </ejb-relation>
  </relationships>
CODE----->for CourseBean and StudentBean.
//cmr methods in CourseBean
public abstract Collection getStudents();
public abstract void setStudents(Collection s);
//cmr methods in StudentBean.
public abstract Collection getCourses();
public abstract void setCourses(Collection c);
These methods are in addition to the getters/setters, activate etc….