外键值不插入数据库中:无法在列中插入null

Question

我将客户端应用程序从Hibernate迁移到Eclipselink。但是，当调用持久方法对学生实体时，这并不是插入外键的值。数据库是Oracle。地址和学生之间有很多关系。

在生成的SQL中也不存在外键列。

@Entity
@Table(name = "Student", schema = "Student_DB")
@SequenceGenerator(name = "studentSeq", sequenceName = "Student_SEQ", schema = "Student_DB", allocationSize = 1)
public class StudentEntity implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "studentSeq")
    @Column(name = "S_ID")
    private BigDecimal studentID;
    @OneToMany(mappedBy = "studentEntity", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
    @JoinColumn(name = "S_ID")
    private List<AddressEntity> addresses;
}
addAddress(address){
  address.setStudentEntity(this);

---

@Entity
@Table(name = "Address", schema = "Student_DB")
@SequenceGenerator(name = "AddressSeq", sequenceName = "Address_SEQ", schema = "Student_DB", allocationSize = 1)
public class AddressEntity implements Serializable {
    @Id
    @Column(name = "A_ID")
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "AddressSeq")
    private long addressID;
    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "S_ID", referencedColumnName = "S_ID", insertable = false, updatable = false, nullable = false)
    private StudentEntity studentEntity;
}

---

*

> [EL Fine]: sql: 2019-06-25
> 18:39:00.895--ClientSession(1656550367)--Connection(-872205654)--INSERT
> INTO Student_DB.Student (S_ID, ...) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?,
> ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)  bind => [24 parameters
> bound] [EL Fine]: sql: 2019-06-25
> 18:39:00.946--ClientSession(1656550367)--Connection(-872205654)--INSERT
> INTO Student_DB.Address (A_ID, CO...) VALUES (?, ?, ?, ?, ?)  bind =>
> [5 parameters bound] [EL Fine]: sql: 2019-06-25
> 18:39:00.954--ClientSession(1656550367)--SELECT 1 FROM DUAL [EL
> Warning]: 2019-06-25 18:39:00.955--UnitOfWork(-922357549)--Exception
> [EclipseLink-4002] (Eclipse Persistence Services -
> 2.5.0.v20130507-3faac2b): org.eclipse.persistence.exceptions.DatabaseException Internal
> Exception: java.sql.SQLIntegrityConstraintViolationException:
> ORA-01400: cannot insert NULL into ("Student_DB"."Address"."S_ID")

*

Answer 1

正确的映射看起来像：

@Entity
@Table(name = "Student", schema = "Student_DB")
@SequenceGenerator(name = "studentSeq", sequenceName = "Student_SEQ", schema = "Student_DB", allocationSize = 1)
public class StudentEntity implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "studentSeq")
    @Column(name = "S_ID")
    private BigDecimal studentID;
    @OneToMany(mappedBy = "studentEntity", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
    private List<AddressEntity> addresses;
}

@Entity
@Table(name = "Address", schema = "Student_DB")
@SequenceGenerator(name = "AddressSeq", sequenceName = "Address_SEQ", schema = "Student_DB", allocationSize = 1)
public class AddressEntity implements Serializable {
    @Id
    @Column(name = "A_ID")
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "AddressSeq")
    private long addressID;
    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "S_ID", referencedColumnName = "S_ID", nullable = false)
    private StudentEntity studentEntity;
}