我正在嘗試Raadpleging從我的數(shù)據(jù)庫中返回對象。這些對象包含 aPersoon和 a Les。我的目標(biāo)是返回所有 Raadplegingen，其中 Les 的 ID 等于參數(shù)。我不確定如何在我的查詢中執(zhí)行此操作。我也不太確定我的第一個(gè) namedQuery 是否也會(huì)返回 Persoon 和 Les 屬性，或者我是否需要一個(gè)連接。正如您在下面看到的，我嘗試使用這樣的參數(shù)WHERE r.les  = :lesId，我認(rèn)為這是不正確的。@Entity@Access(AccessType.PROPERTY)@Table(name = "Raadplegingen")@NamedQueries({    @NamedQuery(name = "ClubRaadpleging.getAlleRaadplegingen",            query = "SELECT r FROM ClubRaadpleging r"),    @NamedQuery(name = "ClubRaadpleging.findByLes",            query = "SELECT r FROM ClubRaadpleging r JOIN ClubLes l ON l.id =r.les.id WHERE r.les  = :lesId")})public class ClubRaadpleging implements Serializable {    private int id;    private ClubLes les;    private ClubPersoon persoon;    private Date datum;    public ClubRaadpleging() {    }    @Id    @GeneratedValue(strategy = GenerationType.IDENTITY)    @Column(name = "RaadplegingId")    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    @ManyToOne(cascade = CascadeType.PERSIST)    @JoinColumn(name = "LesId")    public ClubLes getLes() {        return les;    }    public void setLes(ClubLes les) {        this.les = les;    }    @ManyToOne(cascade = CascadeType.PERSIST)    @JoinColumn(name = "PersoonId")    public ClubPersoon getPersoon() {        return persoon;    }    public void setPersoon(ClubPersoon persoon) {        this.persoon = persoon;    }    @Temporal(TemporalType.DATE)    public Date getDatum() {        return datum;    }    public void setDatum(Date datum) {        this.datum = datum;    }}