Hibernate Subselect vs Batch Fetching

Question

Hibernate provides (at least) two options for getting around the N+1 query problem. The one is setting the FetchMode to Subselect, which generates a select with a IN-clause

Answer 1

I found this article to be helpful. I believe batch-fetching can be applied on both the collection and the parent, while subselect can only be applied on a collection.

In case of a fetching strategy for collections, a subselect will be executed once (because the batch-size is effectively infinity), while with batch-fetching the SQL statement might be executed multiple times.