I have two classes, Project and Memo. Each Memo is associated with one Project, but a Project can have several Memos.

So, Project has a one-to-many relationship with Memo, and Memo has a many-to-one relationship with Project.

In the database schema, T_PROJECTS and T_MEMOS are connected via T_PROJECT_MEMO_LINK (PROJECTID and MEMOID).

Since this is a 1:M/M:1 via a link table, what would the mapping look like?

Jason

Hi Jason,
one solution is to add a link class in between.

in the Memo class:
<many-to-one name="projectMemoLink" class="ProjectMemoLink" column="xxx" not-null="true" insert="false" update="false"/>

in the ProjectMemoLink class:
<many-to-one name="project" column="xxx" not-null="true"/>
<many-to-one name="memo" column="xxx" not-null="true"/>

and in the Project class:
<bag name="projectMemoLinks" lazy="false" inverse="true" cascade="all-delete-orphan">
<key column="xxx" not-null="true"/>
<one-to-many class="ProjectMemoLink"/>
</bag>

The Link class can be helpful if you need to store extra stuff like update date or update user id.

hope that helps,
Seb