I'm using a legacy database schema with composite keys. I have an entity with two relationships and one of the join columns is shared.

For example, Let's say i have a Student entity with two relationships Department and Course. Department uses dept_code column while Course uses dept_code and course_code colum. The domain model is such that a student might belong to a department and not opted for a course yet or both.

This is how the hibernate mapping looks like:

<hibernate-mapping>
<class name="Student" table="students">
<id column="id" name="id" type="integer">
<generator class="native"/>
</id>
<property column="name" name="name" type="string"/>

<many-to-one class="Department" name="department">
<column name="dept_code"/>
</many-to-one>

<many-to-one class="Course" name="course>
<column name="dept_code"/>
<column name="course_code"/>
</many-to-one>
</class>
</hibernate-mapping>

The problem is Hibernate does not allow this mapping unless one of the relationships is marked readonly using insert=false and update=false.

Is there a way to have both relationships as writable?

try this instead.