Question

I’m trying to get distinct results using the Criteria API in NHibernate. I know this is possible using HQL, but I would prefer to do this using the Criteria API, because the rest of my app is written using only this method. I found this forum post, but haven’t been able to get it to work. Is there a way with the criteria API to get distinct result sets?

Edit: In doing this, I also wanted to exclude the Primary Key column, which is also an identity, and get the remaining distinct records. Is there a way to do this? As it is, the distinct records are returning duplicates because the primary key is unique for each row, but all other fields are the same.

Answer 1

Cannot see the forum post at this moment (broken link?), so maybe this is not the answer, but you can add a DistinctRootEntityResultTransformer:

session.CreateCriteria(typeof(Product)     .Add(...)     .SetResultTransformer(new DistinctEntityRootTransformer())