Hello,

I have lazy set and when trying to add new item to that set nhibernate loads all the other, previously saved items.

Question1 : is that ok?

Question2: how to prevent such a behavior?

Thanks

The behaviour is normal. The lazy property tells hibernate not to load the object or collection until it is needed (aka accessed). Yet when you add a an item of a collection, you are accessing the collection (hence the load).

I don't believe there is a way arround this.

Afaik you can prevent this with using a bag. Since a bag can contain duplicate items hibernate does not have to load the other items make sure that the collection semantics are not violated. But I'm not sure if it really works that way.