Question

我有一个实体Answer，它有一个复合id AnswerId，它有一个Person实体和一个Question实体，它们分别有personId和questionId的字符串ID。此外，Question实体有一个字段questionText。

如果我尝试这样的话：

Criteria criteria = session.createCriteria(AnswerEntity.class);
criteria.add(Restrictions.eq("answerId.person.personId", personId));
criteria.add(Restrictions.eq("answerId.question.questionId", questionId));

它的工作原理是它根据提供的personId和questionId过滤结果。

但是，如果我尝试：

Criteria criteria = session.createCriteria(AnswerEntity.class);
criteria.add(Restrictions.eq("answerId.person.personId", personId)); 
criteria.add(Restrictions.like("answerId.question.questionText",questionText));

失败了。它说它无法找到questionText，生成的SQL显示原因：

SELECT this_.PERSON_ID AS PERSON6_5_0_,
  this_.QUESTION_ID    AS QUESTION5_5_0_,
  this_.THEIR_ANSWER   AS THEIR3_5_0_,
FROM ANSWER this_
WHERE q1_.QUESTION_TEXT LIKE ?
AND this_.PERSON_ID=?

如何在答案和问题之间加入，以便我可以访问questionText？我尝试添加像

这样的别名

criteria.createAlias("answerId.question", "q"); 
criteria.add(Restrictions.like("q.questionText", "%" + text + "%"));

但这似乎不起作用。任何人都能提供一些帮助，说明我做错了吗？

编辑：奇怪的是，Person实体也有一组Answers，这样我就可以对Person进行查询并使用类似"answers.answerId.question.questionText"的限制进行过滤，它实际上有效。我不确定有什么不同。

编辑：我的实体（没有getter / setters / equals / etc）

@Entity
@Table(name = "ANSWER")
public class AnswerEntity implements Serializable
{
    private static final long serialVersionUID = -8254277382097937813L;

    @EmbeddedId
    private AnswerId answerId;

    @Column(name = "THEIR_ANSWER")
    private int theirAnswer;
}

@Embeddable
public class AnswerId implements Serializable
{
    private static final long serialVersionUID = 7025913625856563058L;

    @OneToOne
    @Index(name = "ANSWER_QUESTION_ID_INDEX")
    @JoinColumn(name = "QUESTION_ID")
    @ForeignKey(name = "FKA1_QUESTION_ID")
    private QuestionEntity question;

    @ManyToOne
    @Cascade(CascadeType.ALL)
    @Index(name = "ANSWER_PERSON_ID_INDEX")
    @JoinColumn(name = "PERSON_ID")
    @ForeignKey(name = "FKA2_PERSON_ID")
    private PersonEntity person;
}   

@Entity
@Table(name = "QUESTION")
public class QuestionEntity implements Serializable
{
    private static final long serialVersionUID = -3083000088157555984L;

    @Id
    @Column(name = "QUESTION_ID", nullable = false)
    private String questionId;

    @Index(name = "QUESTION_TEXT_INDEX")
    @Column(name = "QUESTION_TEXT", length = 4000, nullable = false)
    private String questionText;
}

Answer 1

只是猜测，试试：

criteria.createAlias("question.questionText", "qText"); 
criteria.add(Restrictions.like("answerId.qText", "%" + text + "%"));

编辑：这背后的推理（为了猜测一个有根据的猜测;）是您不需要别名或SubCriteria导航到myEembedded.myProperty等嵌入属性。您需要别名或SubCriteria才能导航到相关实体的属性，例如myRelatedEntity.myProperty。

HIbernate Criteria别名没有加入

1 个答案: