是否可以在Hibernate中映射表的两列而不是两个表

Question

I am having a situation where 1 table is having 2 columns and they have the many to many relation between them. Let me explain with example I have a table named

StudentCC

StudentId | CoachingCenterId
    1              C1
    1              C2
    2              C1
    2              C2

Now this is a manyToManyRelation between columns of 1 table. I searched internet and didn't find anything related to this.Every suggestion is specific to at least two tables. What I understand is that it can be done in ManyToMany as well as OneToMany and ManyToOne relation mapping. But don't understand how.

I tried to build a ManyToMany relation: Please suggest if its true. And if I have to use this or 2 OneToMany and ManyToOne relation approach.

@ManyToMany(MappedBy="AnyThing" cascade=CascadeType.ALL)
@JoinTable(name="StudentCC" JoinColumns={@JoinColumn(name="StudentId")},
inverseJoinColumns{@JoinColumn(name="CoachingCenterId")})
Private Set<StudentCC> rel = new HashSet<StudentCC>();

---

@ManyToMany(cascade=CascadeType.ALL)
@JoinTable(name="StudentCC" JoinColumns=@JoinColumn(name="CoachingCenterId")},
inverseJoinColumns{@JoinColumn(name="StudentId")})
Private Set<StudentCC> rel = new HashSet<StudentCC>();

Please advice . Thanks in advance.

Answer 1

I belive you cannot have the JointTable(name="StudentCC") as many to many can not group to StudentCC nor coachingCenterID, you will need a new table to hold the many to many between Student and coachingCenter, such as StudentCoachingCenter.

In Student class you want the set with CoachingCenters

 @ManyToMany
    @JoinTable(name="StudentCoachingCenter", 
    joinColumns = {@JoinColumn(name="StudentCC")}, inverseJoinColumns ={@JoinColumn(name="coachingCenterID")})
   private Set<CoachingCenter> coachingCenters;