I get a ObjectNotFoundException: No row with the given identifier exists.

Here's my element

<many-to-one name="Category" column="category_identifier" access="property" fetch="join" />

here's my property declaration

private Category category;

public Category Category
{
get { return category; }
set { category = value; }
}

In my understainding, If I use join fetch it will set outer=true and I'll be able to retrieve referenced categories existing or not.

I have no problem if the referenced category id is existing in the category Id. but when the category id is not existing, the above exception occurs.

I thought the fetch = join would solve my problem.

Am I missing something here?
Thanks.