使用Hibernate公式从另一个表中选择实体

Question

我正在尝试使用Hibernate的@Formula注释从另一个表中检索实体.给出以下代码:

@Entity
class Test {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id", updatable = false, nullable = false)
    private Long id = null;

    // ...

    @Formula("(SELECT r FROM Result r WHERE test_id = id AND resultDate = (SELECT MAX(resultDate) FROM Result WHERE test_id = id))")
    private Result lastestResult;

    // ...

    public Result getLatestResult() {
        return latestResult;
    }

    // ...
}

Result类如下所示:

@Entity
class Result {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id", updatable = false, nullable = false)
    private Long id = null;

    @ManyToOne
    private Test test;

    // ...
}

但是在尝试加载Test实体时,我收到错误"Column"TEST0_.RESULTDATE"not found".我已经尝试过其他一些涉及@JoinFormula注释的东西,但没有任何成功.我也遇到了这个答案,这似乎表明我正在做的事情应该有效,但事实并非如此.我该如何工作？

Answer 1

所以,我找到了解决这个特殊问题的方法.该latestResult物业的注释如下:

@ManyToOne
@JoinColumnsOrFormulas({
    @JoinColumnOrFormula(formula=@JoinFormula(value="(SELECT r.id FROM Result r WHERE resultDate = (SELECT MAX(sqr.resultDate) FROM Result sqr WHERE sqr.test_id = id))", referencedColumnName="id")),
})
private Result latestResult;