Room API-如何获取实体最近插入的生成ID? [英] Room API - How to retrieve recently inserted generated id of the entity?

问题描述

我需要检索最近插入的实体的生成的id值，如下面添加的代码示例所示:

I need to retrieve the generated id value of an entity which is recently inserted as the code sample added below demonstrates:

如上所述，实体Student​​的id字段用PrimaryKey(autoGenerate= true)注释.

As mentioned above, the id field of the entity Student is annotated with PrimaryKey(autoGenerate= true).

Student s = new Student();
s.setName("foo");
// call of other setters
appDatabase.getGenericDAO().insertStudent(s);
// Now I need to retrieve the value of generated id as we do in Hibernate by the usage of merge method
Integer id = s.getId(); 

DAO

@Dao
public interface IGenericDAO {

    @Insert
    Long insertStudent(Student student);

    @Insert
    void insertOgrenci(List<Student> studentList);

    @Update
    void updateOgrenci(Ogrenci... ogrenci);

    @Delete
    void deleteOgrenci(Ogrenci... ogrenci); 

}

推荐答案

让您的@Insert方法返回long:

@Insert
long insertStudent(Student s);

返回值将是该行的rowId，并且应该是自动生成的主键值.

The return value will be the rowId of the row, and that should be the auto-generated primary key value.

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