Hello,
I have problem with collection mapping in Hibernate 3.3.1.GA.

I have two database tables: user(id:number, username:varchar2, pass:varchar2) and userpermission(user_id:number, permission:varchar2).

In my application I have entity User with property Set<String> permissions;

It is mapped with
<set name="permissions" table="USERPERMISSION" lazy="false" fetch="join" inverse="false" cascade="all">
<key column="USER_ID" not-null="true"/>
<element column="PERMISSION" type="string" length="40"
not-null="true"/>
</set>

The set of permissions is always empty although it shouldn't. But hibernate user type's nullSafeGet is called and the resultset contains correct data, but the PersistentSet doesn't.

CAn you advice me?
Thanks
blaf

What make a row unique in your permission table?

This will probably be a lot easier if you put a synthetic key in your child table.

If you have to keep the child table as you've said, then I think you'll need to declare the userid + permission as the key (compound key), since from relational point of view thats what makes it unique.

Probably would be a good idea to show the .java for your child entity (permission)

There's no permission table in database and no Permission neither UserPermission entity in application. The idea is that there's no need to have permission table in db because it would contain static data without ability to change it, so the data will be stored in resource bundles on application level. In database will be only stored codes of permission.

I think I could create UserPermission entity (and map it) and the collection map with <one-to-many/> instead <element/> but I don't need UserPermission entity in application. I thought <element/> element is intended for situations like this, isn't it?