这是我的 JPA 结构:
电影(看看级联类型):
@Entity
@Table(name = "movie")
public class Movie {
@Id
@Column(name = "movie_id")
@GeneratedValue(strategy = GenerationType.AUTO)
private Integer id;
//@OneToMany(cascade = CascadeType.ALL, mappedBy = "primaryKey.movie") //stack overflow
@OneToMany(mappedBy = "primaryKey.movie") //works fine
private List<Rating> ratings;
....
}
Run Code Online (Sandbox Code Playgroud)
评分:
@Entity
@Table(name = "rating")
@AssociationOverrides({@AssociationOverride(name = "primaryKey.movie", joinColumns = @JoinColumn(name = "movie_id")),
@AssociationOverride(name = "primaryKey.user", joinColumns = @JoinColumn(name = "imdb_user_id"))})
public class Rating {
@EmbeddedId
private RatingId primaryKey = new RatingId();
@Column(name = "rating_value")
private Integer ratingValue;
.....
} …Run Code Online (Sandbox Code Playgroud)