在JPQL中通过排序定义引用字段的排序属性 [英] Define sort property for referenced field during order by in JPQL

问题描述

我有两个实体和投影的休息库：
$ b

I have rest repository with 2 entities and projection:

@Entity
public class Person {
    @Id
    @GeneratedValue
    private Long id;

    String name;

    @ManyToOne
    Language language;
}

@Entity
public class Language {
    @Id
    @GeneratedValue
    private Long id;

    private String name;
}

public interface PersonRepository extends PagingAndSortingRepository<Person, Long> {
}

@Projection(name = "details", types = {Person.class})
interface PersonProjection {

    Long getId();

    String getName();

    @Value("#{target.language.name}")
    String getLanguage();
}

当我试图按语言字段排序时b
$ b

When I'm trying to sort it by language field

/ api / persons /？投射=详情& sort =语言

/api/persons/?projection=details&sort=language

它生成SQL，尝试按language.id排序它。

lockquote

select person0_.id as i ... order by language1_.id asc limit？

it produce SQL that trying to sort it by language.id

有没有办法告诉Spring Data，JPA使用不同的默认属性在没有在url中明确指定它的情况下进行排序？

select person0_.id as i... order by language1_.id asc limit ?

推荐答案

Spring配置时使用的属性遍历实体对象。
在您的情况下，对于人员和语言，您在属性名称上有名称冲突。
为了解决这个问题，你的排序参数应该引用正确的属性，即：
按照语言名称排序，你的url应该是/ api / persons /？projection = details& sort = language_name
按人名排序您的url参数shoud look / api / persons /？projection = details& sort = person_name

Spring data-rest as you configured it uses property traversal on your entity objects. In your case, for Person and Language you have a name clash on the property "name". In order to solve this issue your sort param should reference the correct property, i.e: For sorting by language name your url should be like /api/persons/?projection=details&sort=language_name For sorting by person's name your url parameter shoud look /api/persons/?projection=details&sort=person_name

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