java - JPA、 hibernate 、Java。复合主键，其中之一也是外键

Question

我遇到了标题中简短描述的问题。谁能告诉我，如何使用 JPA 获得相同的数据库？

create table ALBUM
( 
 IdAlbum int, 
 AlbumName varchar(35) not null, 
 UrlOfAlbum varchar(60) not null,
 Primary Key(IdAlbum) 
);
create table ARTIST
(
 IdArtist int, 
 ArtistName varchar(35) not null, 
 Primary Key(IdArtist) 
);
create table TRACK
(
 IdTrack int,
 IdAlbum int,
 IdArtist int,
 TrackName varchar(35) not null,
 Primary Key(IdTrack, IdAlbum),
 Foreign Key(IdAlbum) references Album(IdAlbum),
 Foreign Key(IdArtist) references Artist(IdArtist)
);

Answer 1

只需将列放入嵌入键中并在主类中保留关系:

@Embeddable
class TrackId
{
    private Integer idAlbum;
    private Integer idTrack;
    // getters, setters, equals and hashCode
}

@Entity
class Track
{
     @EmbeddedId
     TrackId trackId;

     @ManyToOne
     @MapsId("idAlbum")
     @JoinColumn(name = "idAlbum", referencedColumnName = "idAlbum")
      private Album album = null;

      ....
}