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Hvordan gengiver man en træstruktur i dvale med flere tabeller?

Du ønsker måske at have to kolonner i Relationstabellen,

    @ManyToOne(fetch = FetchType.EAGER, cascade=CascadeType.ALL)
@JoinTable(name="Relationship", joinColumns =  @JoinTable(name = "Relationship", joinColumns = @JoinColumn(name = "parent_id", referencedColumnName = "id"), inverseJoinColumns = @JoinColumn(name = "id", referencedColumnName = "id"))@Fetch(FetchMode.SELECT)
 private Node parentNode;
@OneToMany(fetch=FetchType.EAGER, cascade=CascadeType.ALL)
@JoinTable(name = "Relationship", joinColumns = @JoinColumn(name = "id", referencedColumnName = "id"), inverseJoinColumns = @JoinColumn(name = "parent_id", referencedColumnName = "id"))
@Fetch(FetchMode.SELECT)
 private Set<Node> childNodes;


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