java - 如何在@ManyToOne 字段上创建@Index？

Question

我想使用 hibernate 创建一个@Index。索引应包含 3 个字段，其中一些字段嵌套在其他实体中。我怎样才能做到这一点？

@Table(name = "my_entity", indexes = {
@Index(name = "my_index", columnList = "id, person.firstname, person.lastname")
})
@Entity
public class MyEntity {
   private Long id;

   @ManyToOne
   private Person person;
}

@Entity
public class Person { 
   @Id private Long id;
   private String firstname;
   private String lastname;
}

结果:

Caused by: org.hibernate.AnnotationException: Unable to create unique key constraint (id, person.firstname, person.lastname) on table my_entity: database column 'person.firstname', 'person.lastname' not found. Make sure that you use the correct column name which depends on the naming strategy in use (it may not be the same as the property name in the entity, especially for relational types)
    at org.hibernate.cfg.Configuration.buildUniqueKeyFromColumnNames(Configuration.java:1684)
    at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1459)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1846)
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl$4.perform(EntityManagerFactoryBuilderImpl.java:857)
    ... 46 more

Answer 1

columnList 采用列 名称数组。不是实体属性的数组。

因此您只需提供测试表中列的名称，就像您使用 SQL 定义索引时所做的那样。

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