Question

我遇到了一个奇怪的错误，JPA不是持久性提供程序特定的。我正在使用JPA 2.0，而且我正在使用生成的架构。

简而言之：生成的模式包含一个包含三列的连接表，但生成的insert语句将此表视为只有两列。

以下是映射：

@Entity
@Table( name = "Game" )
public class MatchEntity implements Match, Serializable {

    @Id
    @GeneratedValue( strategy = GenerationType.AUTO )
    private Long id;

    @ManyToOne( targetEntity = ClubEntity.class )
    private Club homeTeam;

    @ManyToOne( targetEntity = ClubEntity.class )
    private Club awayTeam;

    @ManyToMany( targetEntity = PlayerEntity.class )  
    private Collection<Player> homeTeamPlayers;

    @ManyToMany( targetEntity = PlayerEntity.class )
    private Collection<Player> awayTeamPlayers;

    private String location;

    @Temporal( value = TemporalType.DATE )
    @Column( name = "Match_Date" )
    private Date date;

    /* constructor, getters and setters follow */
 }


@Entity
@Table( name = "Club" )
public class ClubEntity implements Club, Serializable {

    @Id
    @GeneratedValue( strategy = GenerationType.AUTO )
    private Long id;

    private String name;

    @OneToMany( fetch = FetchType.EAGER, targetEntity = PlayerEntity.class,
    mappedBy = "club" )
    private Collection<Player> players = new ArrayList<Player>();

    private String fieldName;

    private Boolean archived;

    /* constructor, getters and setters follow */
}

@Entity
@Table( name = "PLAYER" )
public class PlayerEntity implements Player, Serializable {

    @Id
    @GeneratedValue( strategy = GenerationType.AUTO )
    private Long id;

    private String firstName;

    private String surname;

    @Temporal( value = TemporalType.DATE )
    private Date birthDate;

    @Column( name = "pos" )    
    @Enumerated( EnumType.ORDINAL )
    private Position position;

    private Integer number;

    private Boolean archived;

    @ManyToOne( targetEntity = ClubEntity.class, fetch = FetchType.EAGER )
    private Club club;


    /* constructor, getters and setters follow */
}

从这些映射中，创建了以下模式：

create table Club (id bigint generated by default as identity (start with 1), archived bit, fieldName varchar(255) not null, name varchar(255) not null, primary key (id))
create table Game (id bigint generated by default as identity (start with 1), Match_Date date, location varchar(255), awayTeam_id bigint, homeTeam_id bigint, primary key (id))
create table Game_PLAYER (Game_id bigint not null, homeTeamPlayers_id bigint not null, awayTeamPlayers_id bigint not null)
create table PLAYER (id bigint generated by default as identity (start with 1), archived bit, birthDate date, firstName varchar(255) not null, number integer, pos integer, surname varchar(255) not null, club_id bigint, primary key (id))
alter table Game add constraint FK21C0123B2A3B9E foreign key (homeTeam_id) references Club
alter table Game add constraint FK21C012F5972EAF foreign key (awayTeam_id) references Club
alter table Game_PLAYER add constraint FK267CF3AE6AE1D889 foreign key (Game_id) references Game
alter table Game_PLAYER add constraint FK267CF3AED51EDECF foreign key (homeTeamPlayers_id) references PLAYER
alter table Game_PLAYER add constraint FK267CF3AE6CBE869E foreign key (awayTeamPlayers_id) references PLAYER
alter table PLAYER add constraint FK8CD18EE13F2C6C64 foreign key (club_id) references Club

这一行很重要 - 这是连接表。

create table Game_PLAYER (Game_id bigint not null, homeTeamPlayers_id bigint not null, awayTeamPlayers_id bigint not null)

当我尝试持久化游戏实体（MatchEntity.java）时，会发生这种情况：

insert into Game_PLAYER (Game_id, awayTeamPlayers_id) values (?, ?)
Hibernate: insert into Game_PLAYER (Game_id, awayTeamPlayers_id) values (?, ?)
binding '2' to parameter: 1
binding '1' to parameter: 2
reusing prepared statement
insert into Game_PLAYER (Game_id, awayTeamPlayers_id) values (?, ?)
Hibernate: insert into Game_PLAYER (Game_id, awayTeamPlayers_id) values (?, ?)
binding '2' to parameter: 1
binding '2' to parameter: 2
done inserting collection: 2 rows inserted
Inserting collection: [football.model.entities.MatchEntity.homeTeamPlayers#2]
Executing batch size: 2
about to close PreparedStatement (open PreparedStatements: 1, globally: 1)
Could not execute JDBC batch update [insert into Game_PLAYER (Game_id, awayTeamPlayers_id) values (?, ?)]

JPA尝试在连接表中插入两行，每行只影响三个中的两列。

我尝试过：

完全删除映射中的接口
定义显式联接表
使用OpenJPA代替Hibernate

也没有解决问题。

编辑：急切提取的代码：

    @Transactional(readOnly = true)
    public Collection<Match> findAll() {        
        em.createQuery("SELECT m FROM MatchEntity m "
            + "JOIN FETCH m.homeTeamPlayers", MatchEntity.class).getResultList();
        List<MatchEntity> rList = em.createQuery("SELECT m FROM MatchEntity m "
            + "JOIN FETCH m.awayTeamPlayers", MatchEntity.class).getResultList();
        Collection<Match> result = new ArrayList<Match>( rList );
        return result;
    }

Answer 1

也许您需要homeTeamPlayers和awayTeamPlayers的不同联接表：

@ManyToMany( targetEntity = PlayerEntity.class )   
@JoinTable(name = "Game_HomeTeamPlayers")
private Collection<Player> homeTeamPlayers; 

@ManyToMany( targetEntity = PlayerEntity.class ) 
@JoinTable(name = "Game_AwayTeamPlayers")
private Collection<Player> awayTeamPlayers;

JPA生成的SQL语句不正确

1 个答案: