Hello Chaps,

I am sure this is simple, but, cannot make it work. In my mapping file I have a 'version map', the key is the 'version; number (an integer) and the target is the object I want to persist:

<.. Parent Class Def
...
<map name="componentVersions" sort="natural" cascade="save-update">
<key column="parent_id_fk"/>
<composite-map-key class="test.domain.Version">
<key-property name="revision" column="revision"/>
</composite-map-key>
<one-to-many
class="test.domain.VersionedInfo"
/>
</map>
...
/>

This works fine, and I can build up a set of my 'versioned' info objects, and I can retrieve all versioned objects.

Now I want to add a filter such that (if I active the filter in the session) hibernate will only return the latest version. I want to achieve this by telling hibernate to get only the latest result version [i.e: with the 'max(revision)'] e.g:

<map name="componentVersions" sort="natural" cascade="save-update">
<key column="parent_id_fk"/>
<composite-map-key class="test.domain.Version">
<key-property name="revision" column="revision"/>
</composite-map-key>
<one-to-many
class="test.domain.VersionedInfo"
/>
<filter
name="LatestVersionFilter"
condition="revision = (select max(revision) from versioned_info)"
/>
</map>



The above does not work and produces an error:

org.hibernate.util.JDBCExceptionReporter.logExceptions(JDBCExceptionReporter.java:77) >75> SQL Error: 0, SQLState: 42803
org.hibernate.util.JDBCExceptionReporter.logExceptions(JDBCExceptionReporter.java:78) >75> ERROR: aggregates not allowed in WHERE

I understand what the error means, and have tried various 'condition statements' but I always get errors. Has anyone or does anyone know hoe to achieve my desired functionality?

Thanks All!


I am using Hibernate v3.2 and Postgres v8.2.

Not many replies regarding my issue!

In that case if anyone could confirm that it is not possible then I can begin to search for a different solution. Can I assume it is not possible to use an subselect projected aggregated as a condition to a filter?