Here is aother strange problem related with NHibernate
I have a Parent class and two child classes Child1 and Child2 mapped to different tables on the database.
Lets assume that we specified cascade='all' for child bags defined on Parent.hbm.xml. Sample workflow of instantiating parent and child objects is as the following
- Create a parent object.
- Insert 2 Child1 instances to child1 bag
- Insert 3 Child2 instances to child2 bag.
- Flush the session
- Refresh parent object
- We get 6 instances for each child bag (child1 and child2). But we expect 2 Child1 instances in child1 bag and 3 Child2 instances in child2 bag.
Ther problem is : NHibernate performs left outer join on Child1 and Child2 tables when Refresh is called for the parent object. This is unaccaptable, I think NHibernate should initialize child collections with seperate selects commited to the database, or may be distinguish the duplicated child instances automatically in the collections. (using idbag instead of bag is not an option)
Download the test case