I thought the following code would return a list containing one Person, with that Person havig his set of addresses populated:



Instead I get as many Persons as there are addresses for that person. That is, instead of getting one Person holding a set of three addresses, I get a list containing three Persons, each with the same identifying information (e.g., id, socialSecurityNumber).

How can I fix the above query to get my desired result?

In case it helps, the definition of the addresses set is:



I'm using hibernate version 3.0.4.

Using direct session.load( PersonImpl.class, serializableId ) will give you a Person object from which you can retrieve set of addresses. I assume socialSecurityNumber to be serializableId i.e. primaryKey for PersonTable. If not you can use HQL version of the query also.

The "problem" is due to the fact that your addresses are most likely being loaded up with an outer join so for each address you are getting a unique Person/Address combination.

Note that this is what you would get if you executed the raw SQL yourself, Hibernate is simply passing the full result set back to you.

If you call criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY) then it will give you a single instance of your root objects when you execute the query.

criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY) is what I was looking for. It loads Addresses without requiring an extra database hit, and prunes extra copies of the root record.