Is it valid for Hibernate list() to return duplicates?

Question

Is anyone aware of the validity of Hibernate\'s Criteria.list() and Query.list() methods returning multiple occurrences of the same entity?

Answer 1

If you have an object which has a list of sub objects on it, and your criteria joins the two tables together, you could potentially get duplicates of the main object.

One way to ensure that you don't get duplicates is to use a DistinctRootEntityResultTransformer. The main drawback to this is if you are using result set buffering/row counting. The two don't work together.