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copied!<p>Are you modeling a bi-directional referential relationship or an inheritance hierarchy?</p> <p>If the object model is an inheritance hierarchy, then the relationship should not need to be bi-directional, and the solution is to obtain the sub-class instance from the sub-class DAO. This removes the need to navigate from the base class to the sub-class in the base class DAO. This is what I was attempting to explain in my original answer (below).</p> <p>If the object model is a bi-directional relationship, then you need to set inverse="true" on the set or bag at the "one" end of the relationship - in this case BasicEntity.</p> <p>Hibernate 3 allows the use of indexed collections at the "one" end of the relationship, but the Hibernate 2 functionality with set or bag should be enough to test the theory.</p> <p>This link might help: <a href="https://www.hibernate.org/193.html" rel="nofollow noreferrer" title="Bidirectional one-to-many with an indexed collection">https://www.hibernate.org/193.html</a> Also: Hibernate Quickly pp142 - 145; Hibernate in Action pp108 - 111.</p> <hr> <p>If I understand the problem correctly, you want to build a VersionedEntity from two tables, using data obtained like this:</p> <pre><code>select * from basic_entity be, versioned_entity ve where ve.id = be.id and ve.id = <id> and ve.active_version=<version> </code></pre> <p>Given your constraints on not calling one DAO from another, I wonder whether the chosen method correctly expresses the intent: </p> <pre><code>public my.VersionedEntity my.BasicEntityDAO.getActiveVersionedEntity(); </code></pre> <p>Could you implement a method like this instead:</p> <pre><code>public my.VersionedEntity my.VersionedEntityDAO.getActive(); </code></pre>

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