[ome-devel] load object graph

[Bernhard Voigt]

Hi!

I'd like to know the best praxis to load object graphs of objects
which might not have the same childs. E.g. I'd like to get all
wellsamples taken for a given plate. I can do the following:

        query = '''
        select p from Plate p
        join fetch p.wells w
        join fetch w.wellSamples ws
        where p.id = %i
        ''' % plate.getId().val
        queryservice.findByQuery(query, None)

This works well, if there are wellsamples linked to the wells.
However, if the plate does not have wells and/or wellsamples, the
query returns no object at all. Is there a generic approach to the
problem of listing all plates including childs without querying
beforehand whether certain childs exist.

Thanks! Bernhard