JPA：如何提高OneToMany关系的持久性性能

在这种情况下，客户端和文件夹之间是否存在多对多关联或一对多关联？

如果这是一对多关联，则建议您使用双向映射。因为在这种情况下您不需要第三张表。因此（简短地），hibernate将生成较少的查询，并且性能将提高。

@Entity@Table(name="folder")public class Folder {    @Id    private String reference;    @oneToMany(mappedBy="folder", cascade = {CascadeType.ALL}, orphanRemoval = true)    private List<Client> clients= new ArrayList<>();    private Date createDate;    //getters and setters}@Entity@Table(name = "client")public class Client implements Serializable {    @Id    @GeneratedValue(strategy = GenerationType.AUTO)    private int id;    private String name;    @ManyToOne    @JoinColumn(name = "folder_id")    private Folder folder;    //getters and setters}

看到有关@OneToMany关系的真棒帖子：https ://vladmihalcea.com/the-best-
way-to-map-a-onetomany-association-with-jpa-and-
hibernate/

但是，如果您的案例是多对多的，请参阅：https : //vladmihalcea.com/the-best-
way-to-use-the-manytomany-annotation-with-jpa-and-
hibernate/