我试着在jpa中使用一个自定义查询(不是nativeQuery,因为我想将结果映射到一个自定义对象),但我不知道出了什么问题。
@Repository
public interface ChallengeCompletionRepository extends JpaRepository<ChallengeCompletion, Integer>{
List<ChallengeCompletion> findByUser(int uid);
List<ChallengeCompletion> findByChallenge(int cid);
List<ChallengeCompletion> findByUserAndChallenge(int uid, int cid);
@Query(value = "SELECT new com.some.rly.long.package.name.ChallengeScore(user_id, count(id)) " +
"FROM ChallengeCompletion " +
"WHERE challenge_id = :cid " +
"GROUP BY user_id " +
"ORDER BY count(id) DESC")
List<ChallengeScore> fetchUserScoreForChallenge(@Param("cid") int cid);
}
@Data
@NoArgsConstructor
public class ChallengeScore {
public ChallengeScore(UUID userId, int score){
this.score = score;
this.userId = userId;
}
private int score;
private User user;
@JsonIgnore
private UUID userId;
}
@Entity
@Data
@Table(name = "challenge_completions")
public class ChallengeCompletion extends BaseModel{
@ManyToOne
@JsonBackReference
private User user;
@ManyToOne
private Challenge challenge;
@ManyToOne
private Project project;
}
基本模型为:
@MappedSuperclass
@Data
public abstract class BaseModel {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;
@CreationTimestamp
private Timestamp createdAt;
@UpdateTimestamp
private Timestamp updatedAt;
}
错误只是:“查询验证失败…”。我还觉得有点奇怪,我需要为我要构造的类使用完全限定名,。。但这可能是因为这个班不是一个真正的
@Entity
不会自动加载。
可以在此处找到完整的堆栈跟踪:
https://pastebin.com/MjP0Xgz4
干杯
编辑:多亏了@DN1的评论,我可以在发现你确实可以做类似的事情后让它工作
cc.challenge.id
如果您不想给出质询对象,而只想给出id:
@Query(value = "SELECT new com.energiedienst.smartcity.middleware.module.challenge.model.ChallengeScore(cc.user, count(cc.id)) " +
"FROM ChallengeCompletion cc " +
"WHERE cc.challenge.id = :cid " +
"GROUP BY cc.user " +
"ORDER BY count(cc.id) DESC")
List<ChallengeScore> fetchUserScoreForChallenge(@Param("cid") int cid);
@Data
@NoArgsConstructor
public class ChallengeScore {
public ChallengeScore(User user, long score){
this.score = score;
this.user = user;
}
private long score;
private User user;
}