I correctly defined a @ManyToMany and Hibernate generated a USER_GROUP table.
Problem I need to remove all the existing associations between MyUser and MyGroup. Current Solution Now I'm using a entitymanager handled native query: "DELETE FROM USER_GROUP", for some reasons (very very long to explain...) I want to find a different and cleaner solution.
My first idea: Since for what I should do, I need to remove both the user/group associations and all the groups too, I tried to set a Cascade Remove on the @ManyToMany, but this doesn't work.. if I execute HQL "delete from MyGroup" I receive an exception since a FK is violated. And looking around seems that Cascade Remove should not be used with @ManyToMany...
1st Discarded idea move to @OneToMany, @ManyToOne
2nd Discarded idea not very performant.. iterating on all the groups and removing their associated users.