使用JPQL通过联接表进行查询时出错

Question

我正在尝试使用路线实体的源和目的地属性来获取火车实体的列表，它们之间具有一对多的关系。以路线ID为外键的火车表。表名称分别是路线和火车。请查询查询，以帮助我java.lang.IllegalArgumentException: Validation failed for query for method public abstract java.util.List com.infyrail.app.repository.RouteRepository.findBySourceDestination(java.lang.String,java.lang.String)!RouteRepository：

public interface RouteRepository extends JpaRepository<RouteEntity, Integer> {
    @Query("SELECT t FROM train t JOIN route r WHERE r.source=?1 AND r.destination=?2")
    public List<TrainEntity> findBySourceDestination(String source,String destination);
}

RouteEntity：

@Entity
@Table(name="route")
public class RouteEntity {
     @Id              
     @GenericGenerator(name="route_id",
    strategy="com.infyrail.app.generator.RouteIdGenerator")
                @GeneratedValue(generator = "route_id")
    @Min(value = 100)
    @Max(value = 999)
    Integer id;

    String source;
    String destination;
    @OneToMany(mappedBy = "route",
            cascade=CascadeType.ALL,orphanRemoval = true)

    private List<TrainEntity> trainList;
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getSource() {
        return source;
    }
    public void setSource(String source) {
        this.source = source;
    }
    public String getDestination() {
        return destination;
    }
    public void setDestination(String destination) {
        this.destination = destination;
    }
    public List<TrainEntity> getTrainList() {
        return trainList;
    }
    public void setTrainList(List<TrainEntity> trainList) {
        this.trainList = trainList;
    }

}

TrainEntity：

@Entity
@Table(name="train")
public class TrainEntity {

    //@GeneratedValue(strategy = GenerationType.IDENTITY)
     @Id              
     @GenericGenerator(name="train_id",
    strategy="com.infyrail.app.generator.TrainIdGenerator")
                @GeneratedValue(generator = "train_id")
    @Min(value = 100)
    @Max(value = 999)
    Integer id;
    String trainName;
    String arrivalTime;
    String departureTime;
    Double fare;
    @ManyToOne(fetch = FetchType.LAZY)
    @Autowired
    RouteEntity route;
    public RouteEntity getRoute() {
        return route;
    }
    public void setRoute(RouteEntity route) {
        this.route = route;
    }
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getTrainName() {
        return trainName;
    }
    public void setTrainName(String trainName) {
        this.trainName = trainName;
    }
    public String getArrivalTime() {
        return arrivalTime;
    }
    public void setArrivalTime(String arrivalTime) {
        this.arrivalTime = arrivalTime;
    }
    public String getDepartureTime() {
        return departureTime;
    }
    public void setDepartureTime(String departureTime) {
        this.departureTime = departureTime;
    }
    public Double getFare() {
        return fare;
    }
    public void setFare(Double fare) {
        this.fare = fare;
    }


}

Answer 1

将nativeQuery = true添加到@Query注释：

@Query("SELECT t FROM train t JOIN route r WHERE r.source=?1 AND r.destination=?2", nativeQuery = true)

或使用带有@Param批注的参数。

@Query("SELECT t FROM train t JOIN route r WHERE r.source=:source AND r.destination=:destination")
public List<TrainEntity> findBySourceDestination(@Param("source") String source, @Param("destination") String destination);

查找更多信息here