Sequel Accessing Many_To_Many Join Table When Adding Association

Sequel accessing many_to_many join table when adding association

The recommended way to do this is to add a model for the join table. However, if you don't want to do that, you can do:

class Wishlist
  def _add_item(item, hash={})
    model.db[:items_wishlists].insert(hash.merge(:item_id=>item.id, :wishlist_id=>id))
  end
end

Hibernate JPA No join table created on ManyToMany association

You're mixing field and accessor use for your mapping annotations. You can't do that. In any given class, mapping annotations must be either all on the getters or all on the fields. If you try to mix them, some on the getters and some on the fields, Hibernate will pick getters or fields and ignore the other (I'm not sure if its specified how Hibernate chooses if you don't specify).

Your @Id annotation in each class is on a getter, and that's making Hibernate use your getter-based annotations. Either move the @Id and @GeneratedValue annotations to the id field in each class, or define a getter (and setter) for the actor/film relationship and move the @ManyToMany and @JoinTable annotations to the new getter.

With the annotations on the fields, Hibernate will bypass your getters/setters and access the entity internal fields directly. With them on the getters, Hibernate will call your getters and setters.

Many to many association without join table

JPA does not allow this as it requires foreign keys to reference the full primary key for identity purposes, and it might not work well with caching. If you can, I would recommend switching to a more traditional model using a relation table that uses the actual primary keys.

If your provider allows mapping partial pks (I believe Hibernate does), what you would do is make two 1:M mappings each using a JoinColumn instead of JoinTable, but mark the one on Node->Authority as insertable=false, updatable=false

For example, something like:

public class Node {
    @Id
    private Integer id;
    private String nameNode;
    @OneToMany
    @JoinColumn(name = "idAuthorites", referencedColumnName = "idAuthorites", insertable=false, updatable=false)
    private Set<Authority> authorities;
    ...

public class Authority {
    @Id
    private AuthorityPK pk;
    private String person;
    @OneToMany
    @JoinColumn(name = "idAuthorites", referencedColumnName = "idAuthorites")
    private Set<Node> nodes;
    ...

Hibernate many-to-many association not updating join table

How about using merge? That is what you are cascading after all and you have modified a detached object and need to merge back the changes:

public void update(User user)  {
  dao.merge(user);
}

EDIT: for clarity this replaces the old update method, so it should be called from the client side with loggedInUser, just like before.

EDIT 2: as noted in the comments merge will update all fields. The old update method also seems to do that? Optimistic locks (version numbers) can be used to guard against overwriting other changes by mistake.

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