Question

我有两个与OneToMany关系绑定的DAO类，如下面的代码片段所示。

@Entity
@Table ( name = “Parent_Result”)
public class Parent {

    @Id
    @GeneratedValue
    @Column
    private Long Id;

    @Column
    private String value;

    @OneToMany(fetch = FetchType.EAGER, mappedBy = “parentResult”, targetEntity = Child.class,
        cascade = Cascadetype.ALL)
    private set<Child> childSet;
}

@Entity
@Table ( name = “Child_Result”)
public class Child {

    @Id
    @Column
    @GeneratedValue
    private Long id;

    @Column
    private String result;

    @ManyToOne(fetch = FetchType.EAGER, cascade = CascadeType.MERGE)
    @JoinColumn(name = “parent_id”, referencedColumnName = “id”)
    private Parent parentResult;
}

public class ParentDal {

    @Autowired
    ParentRepository _parentRepo;

    @Autowired
    ChildRepository _childRepo;

    @transactional ( readOnly  =false, propogation = Propogation.REQUIRED)
    public void saveResults( Parent parentResult) {
        _parentRepo.saveAndFlush(parentResult);
        for(Child childResult : parentResult.getChildSet() ) {
            // Save parent PK in child. A requirement.
            _childRepo.saveOrUpdateParentIdInChild(parentResult.getId(),
                                                     childResult.getId());
        }
    }
}

ChildRepository.java如下 -

public interface ChildRepository extends JpaRepository<Child, Long> {
     @Modifying
     @Transactional
     @Query(value = "update Child_Result set parent_id = ?1 where 
         id = ?2", nativeQuery = true)
         // id = (CAST( (?2) AS bigint))", nativeQuery = true) //-------> (2)
         // id = (?2::bigint)", nativeQuery = true)   //--------> (3)

     void saveOrUpdateParentIdInChild(Long parent_id, Long id);

}

当我们第一次尝试插入孩子时，每件事都很好，我们确实在DB表中输入了父和子。子条目也会填充父母的PK。

当我们尝试更新或删除已存在的条目时出现问题。调用'saveOrUpdateParentIdInChild'后，它不会更新现有结果并抛出异常，如下所示 -

[WARN] [30 Sep 21:55:18] - org.hibernate.util.JDBCExceptionReporter - SQL Error: 0, SQLState: 42883
[ERROR] [30 Sep 21:55:18] - org.hibernate.util.JDBCExceptionReporter - ERROR: operator does not exist: bigint = bytea
  Hint: No operator matches the given name and argument type(s). You might need to add explicit type casts.

似乎在＆＃39;其中＆＃39;存储库类中的子句被视为字节数组，而它假设为bigint。正如提示中所建议的那样，我试图将？2转换为bigint（如（2）和（3）注释中所示）但是我抛出了另一个异常，即bytearray无法转换为bigint。

我被困在这个问题中相当一天半。仍然不知道如何解决这个问题。请让我知道我在这里做错了什么。为什么更新/删除失败。

编辑：

在发布我的问题之前，我还经历了以下SO帖子：

No operator matches the given name and argument type(s). You might need to add explicit type casts. -- Netbeans, Postgresql 8.4 and Glassfish

heroku, postgreSQL, django, comments, tastypie: No operator matches the given name and argument type(s). You might need to add explicit type casts

＆＃39;运营商不存在＆＃39;修改表

0 个答案: