由于多态实体中的@DiscriminatorColumn，EclipseLink是否会导致ORA-00957：重复的列名错误？

Question

我试图在Oracle数据库中保留实体对象时遇到此异常，我在将JPA项目切换为 EclipseLink 2.0 来自 Hibernate ，我正在使用“实体继承”，如果这可能与它有任何关系（我非常怀疑）。

*

Caused by: javax.persistence.PersistenceException: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.0.1.v20100213-r6600): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: ORA-00957: duplicate column name
Error Code: 957
Call: INSERT INTO SUREC (ID, PERSON_ID, SURECID, VERSIYONNO, FAZ, FORM_TARIH, DURUMKODU_ID, surecId) VALUES (...

*

异常消息表明SURECID在SQL中生成了两次，似乎导致了重复列错误，但是surecId被定义为属性并在实体类中注释为discriminator列:(见下文）

基本实体类类似于：

@Entity
@Inheritance(strategy=InheritanceType.JOINED)
@DiscriminatorColumn(name = "surecId")
public class Surec implements java.io.Serializable {

    private static final long serialVersionUID = -6008473677883005878L;
    @Column(name = "ID")
    private Long id;
    @Basic(optional = false)
    @Column(name = "FAZ")
    private int faz;
    @Basic(optional = false)
    @Column(name = "FORM_TARIH")
    @Temporal(TemporalType.DATE)
    private Date formTarih;
    @Column(name = "PERSON_ID")
    private Integer personId;
    // @Column(name = "SURECID", updatable = false, length=17)
    @Column(updatable = false, length=17)
    private String surecId;
    @Column(name = "VERSIYONNO")
    private Long versiyonno;
    @JoinColumn(name = "DURUMKODU_ID", referencedColumnName = "ID")
    @ManyToOne
    private DurumKod durumKodu;

    public Surec() {
    }

    public Surec(String surecId) {
        this.surecId = surecId;
    }

    public Long getId() {
        return id;
    }

    public void setId(Long id) {
        this.id = id;
    }
    .
    .
    .
    public String getSurecId() {
        return surecId;
    }

    public void setSurecId(String surecId) {
        this.surecId = surecId;
    }
    .
    .
    .

我评论了“@Column（name = ...”注释jus，看它是否会导致重复列错误，但它没有用完。

以下是扩展 Surec.java 的多态实体：

@Entity
@DiscriminatorValue("atf")
public class MailOrder extends Surec {
    private static final long serialVersionUID = 8333637555543614502L;

    @Column(name = "AMOUNT")
    private Double amount;
    @Basic(optional = false)
    @Column(name = "CURRENCY", length = 17)
    private String currency;
    @Column(name = "BANK")
    private String Bank;
    @Column(name = "ACCOUNT_ID", length = 31)
    private String accountId;
    @Column(name = "INVOICE_ID")
    private Integer invoiceId;

    public MailOrder() {
    }

    public MailOrder(String surecId) {
        super(surecId);
    }

    public String getCurrency() {
        return currency;
    }
    .
    .
    .

当我尝试持久保存这个子实体时会发生错误。 它不会覆盖其超类的任何属性，虽然我不确定它是否是构造函数...

任何建议解决问题（以及确认任何可能的EclipseLink或Oracle（或我的！）错误都将受到赞赏。

Answer 1

如果您有使用此字段的关系映射，并且与区分大小写有关，则这是一个常见问题。尝试将descriminator colum指示为 @DiscriminatorColumn（name =“SURECID”）

默认情况下，EclipseLink区分大小写，这就是为什么surecId被视为与SURECID不同的字段。您可以使用eclipselink.jpa.uppercase-column-names属性使EclipseLink不区分大小写，当设置为true时，强制EclipseLink在字段名称比较时使用大写。

Answer 2

我猜您需要将该属性标记为insertable = false, updateable = false，因为它已作为鉴别器插入：

@Column(insertable = false, updatable = false, length=17)
private String surecId;