近期项目中需要 关联 几张表再把字段转出来，在这里记录以下，我感觉网上写的都不太规范和清晰。
@Entity
@SqlResultSetMapping(
name="TestMapping",
entities = {
@EntityResult(
entityClass = com.xxx.xx.data.model.TestEntity.class,
fields = {
@FieldResult(name="id",column="id"),
@FieldResult(name="localTime",column="time"),
@FieldResult(name="maximumAppointment",column="maxAppointment"),
}
)
}
)
@NamedNativeQuery(name="getTestQuery",
query="select tableC.id as id,tableB.time,tableC.maximumAppointment as maxAppointment from tableB " +
" inner join tableA on tableA.id = tableB.tableAId " +
" inner join tableC on tableB.id = tableC.tableBId " +
" inner join custom on custom.id = tableA.customId " +
"where " +
" tableA.locationId = :locationId" +
" and custom.id = :customId" +
" and tableB.deleted = false ", resultSetMapping="TestMapping")
@Data
public class TestEntity {
@Id
private String id;
private LocalTime localTime;
private Integer maximumAppointment;
}
需要声明接口：
@Repository
public interface TestEntityRepository extends JpaRepository<TestEntity,String> {
@Query(name="getTestQuery")
List<TestEntity> getTestQuery(String locationId, String customId);
}
若不想声明接口，那可以用EntityManager 来实现。
CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
