如何將JPQL加入同一張表

Question

我在我的數據庫中有一個表，其中包含sportsresults，我需要從表中選擇特定事件期間競爭對手的最後結果。

我有這個表：

SELECT * FROM 
    (SELECT EventStageID as esi, CompetitorID as cid, Max(Lap) as MaxLap FROM srt_outright_season_event_stage_result_live WHERE EventStageID = 191666 GROUP BY CompetitorID) as y 
LEFT JOIN 
    (SELECT * FROM srt_outright_season_event_stage_result_live) as x 
ON x.CompetitorID = y.cid AND x.Lap = y.MaxLap AND x.EventStageID = y.esi; 

其中給出以下結果：

+--------+--------+--------+--------------+--------------+------+----------+--------+--------------+------+----------------+-----------+--------+----------+-----------+ 
| esi | cid | MaxLap | EventStageID | CompetitorID | Lap | Time  | Status | PitstopCount | Grid | FastestLapTime | Substatus | Points | Position | StageType | 
+--------+--------+--------+--------------+--------------+------+----------+--------+--------------+------+----------------+-----------+--------+----------+-----------+ 
| 191666 | 4521 |  0 |  191666 |   4521 | 0 | Finished | NULL |   NULL | NULL | 2:00.175  | NULL  | NULL |  4 |   5 | 
| 191666 | 4524 |  0 |  191666 |   4524 | 0 | Finished | NULL |   NULL | NULL | 2:04.053  | NULL  | NULL |  10 |   5 | 
| 191666 | 4533 |  0 |  191666 |   4533 | 0 | Finished | NULL |   NULL | NULL | NULL   | NULL  | NULL |  13 |   5 | 
| 191666 | 4538 |  0 |  191666 |   4538 | 0 | Finished | NULL |   NULL | NULL | 2:01.218  | NULL  | NULL |  6 |   5 | 
| 191666 | 5769 |  0 |  191666 |   5769 | 0 | Finished | NULL |   NULL | NULL | 2:00.050  | NULL  | NULL |  3 |   5 | 
| 191666 | 7135 |  0 |  191666 |   7135 | 0 | Finished | NULL |   NULL | NULL | 1:59.431  | NULL  | NULL |  1 |   5 | 
| 191666 | 7138 |  0 |  191666 |   7138 | 0 | Finished | NULL |   NULL | NULL | NULL   | NULL  | NULL |  18 |   5 | 
| 191666 | 7610 |  0 |  191666 |   7610 | 0 | Finished | NULL |   NULL | NULL | 1:59.486  | NULL  | NULL |  2 |   5 | 
+--------+--------+--------+--------------+--------------+------+----------+--------+--------------+------+----------------+-----------+--------+----------+-----------+ 

我

+----------------+---------------+------+-----+---------+-------+ 
| Field   | Type   | Null | Key | Default | Extra | 
+----------------+---------------+------+-----+---------+-------+ 
| EventStageID | int(11)  | NO | PRI | NULL |  | 
| CompetitorID | int(11)  | NO | PRI | NULL |  | 
| Lap   | int(11)  | NO | PRI | NULL |  | 
| Time   | varchar(255) | YES |  | NULL |  | 
| Status   | varchar(255) | YES |  | NULL |  | 
| PitstopCount | int(11)  | YES |  | NULL |  | 
| Grid   | int(11)  | YES |  | NULL |  | 
| FastestLapTime | varchar(255) | YES |  | NULL |  | 
| Substatus  | varchar(255) | YES |  | NULL |  | 
| Points   | decimal(10,2) | YES |  | NULL |  | 
| Position  | int(11)  | YES |  | NULL |  | 
| StageType  | int(11)  | YES |  | NULL |  | 
+----------------+---------------+------+-----+---------+-------+ 

我可以從正常的SQL查詢這樣的表中選擇有此實體類：

@Entity(name = "event_stage_result_live") 
public class EventStageResultLive { 

    @EmbeddedId 
    private PKEventStageResultLive pkEventStageResultLive; 
    // Composite PK contains EventStageID, CompetitorID and Lap 

    @Column(name = "Time") 
    private String time; 

    @Column(name = "Status") 
    private String status; 

    @Column(name = "PitstopCount") 
    private Integer pitstopCount; 

    @Column(name = "Grid") 
    private Integer grid; 

    @Column(name = "Position") 
    private Integer position; 

    @Column(name = "FastestLapTime") 
    private String fastestLapTime; 

    @Column(name = "Substatus") 
    private String substatus; 

    @Column(name = "Points") 
    private Float points; 

    @Column(name = "StageType") 
    private StageType stageType; 

    // getters and setters... 
} 

Answer 1

我認爲在SQL中你可以做這樣的事情。我不認爲加入是必需的。

select * from srt_outright_season_event_stage_result_live c 
    where c.CompetitorID = :competitorID and c.EventStageID = 191666 
     and c.Lap = (select max(d.lap) from srt_outright_season_event_stage_result_live d 
       where d.CompetitorID = :competitorID and d.EventStageID = 191666) 

傳遞給JPQL是

select e from EventStageResultLive e 
    where e.pkEventStageResultLive.CompetitorID = :competitorID and c.pkEventStageResultLive.EventStageID = 191666 
     and e.pkEventStageResultLive.Lap = (select max(d.pkEventStageResultLive.lap) from EventStageResultLive d 
       where d.pkEventStageResultLive.CompetitorID = :competitorID and d.pkEventStageResultLive.EventStageID = 191666) 

假設

public class PKEventStageResultLive{ 
    private int CompetitorID ; 
    private int EventStageID ; 
    private int Lap; 
} 

如果屬性的名稱是不同的正確名稱在JPQL

而且competitorID作爲命名參數。