Question

我有一个带有List注释的@OneToMany作为Java中的Entity变量。问题是，如果我在列表中添加新的RequestPeople或RequestProject，然后执行foo.update()来更新存储在数据库中的现有Request，那么Java会尝试创建新的由于REQUESTS_PEOPLE和REQUESTS_PROJECTS表中的UNIQUE_KEY约束而导致行失败。
这是课程：

家长实体 - 请求

@Entity
@Table(name = "REQUESTS")
public class Request extends Model
{
   @Id
   @GeneratedValue
   @Column(name = "id")
   private long id;

   @OneToMany(mappedBy = "request", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
   private List<RequestPeople> peopleList;

   @OneToMany(mappedBy = "request", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
   private List<RequestProject> projectsList;

   // constructors, getters, setters
}

儿童 - 请求人

@Entity
@Table(name = "REQUESTS_PEOPLE",
       uniqueConstraints = @UniqueConstraint(columnNames = {"request_id", "person_id"}))
public class RequestPeople extends Model
{
   @Id
   @GeneratedValue
   private long id;

   @ManyToOne(targetEntity = Request.class, fetch = FetchType.EAGER)
   @JoinColumn(name = "request_id", referencedColumnName = "id", nullable = false)
   private Request request;

   @ManyToOne(targetEntity = Person.class)
   @JoinColumn(name = "person_id", referencedColumnName = "id", nullable = false)
   private Person person;

   // constructors, getters, setters
}

Child - RequestProject

@Entity
@Table(name = "REQUESTS_PROJECTS",
       uniqueConstraints = @UniqueConstraint(columnNames = {"request_id", "project_id"}))
public class RequestProject extends Model
{
   @Id
   @GeneratedValue
   private long id;

   @ManyToOne(targetEntity = Request.class, fetch = FetchType.EAGER)
   @JoinColumn(name = "request_id", referencedColumnName = "id", nullable = false)
   private Request request;

   @ManyToOne(targetEntity = Project.class)
   @JoinColumn(name = "project_id", referencedColumnName = "id", nullable = false)
   private Project project;

   // constructors, getters, setters
}

第三实体（人和项目）只是简单的实体。以下是这些ID：

@Id
@GeneratedValue
@Column(name = "id")
private long id;

上述实体在DB（MySQL）中创建3个表。在某些时候，我创建了new ArrayList<RequestPeople>()和new ArrayList<RequestProject>()，并使用实体填充这些内容。当我将这些列表添加到tempRequest Request.class类型并执行tempRequest.save()时，Java会将tempRequest存储到REQUESTS表中，对于它创建的列表其他表中的多个条目。 这很好用

问题是当我尝试在peopleList（或项目）中添加新人时。如果我从数据库返回上一个实体，在列表中添加新人并执行tempRequest.update()，则会抛出PersistenceException，表明它违反了子表中的UNIQUE_KEY约束。

javax.persistence.PersistenceException: ERROR executing DML bindLog[] error[Duplicate entry '1-30' for key 'uq_acccess_requests_people_1']
    at com.avaje.ebeaninternal.server.persist.dml.DmlBeanPersister.execute(DmlBeanPersister.java:90)
    at com.avaje.ebeaninternal.server.persist.dml.DmlBeanPersister.insert(DmlBeanPersister.java:57)
    at com.avaje.ebeaninternal.server.persist.DefaultPersistExecute.executeInsertBean(DefaultPersistExecute.java:59)
    at com.avaje.ebeaninternal.server.core.PersistRequestBean.executeNow(PersistRequestBean.java:451)
    at com.avaje.ebeaninternal.server.core.PersistRequestBean.executeOrQueue(PersistRequestBean.java:485)
    at com.avaje.ebeaninternal.server.persist.DefaultPersister.insert(DefaultPersister.java:261)
.
.
.

知道如何解决此错误吗？

PS 我们正在使用Ebean ORM来持久化对象

修改

以下是我从数据库中检索条目的方法：

Request tempRequest = Ebean.find(Request.class).where().eq("id", id).findUnique();

使用Java持久性更新持久化的List <entity>

修改

0 个答案: