JPA连接有两个字段的表，其中一个是主键

Question

问题是@ManyToOne@Joincolumn ID_REPORT（它是一个主键）和@Joincolumn ID_TEMPLATE_DEFAULT

实体映射中的重复列：CurReport 列：id_report（应使用插入=“false”更新=“false”进行映射）

代码

第一桌CUR_TEMPLATE

CREATE TABLE CUR_TEMPLATE 
   (    
    ID_REPORT NUMBER(5,0) NOT NULL, 
    ID_TEMPLATE NUMBER(5,0) NOT NULL, 
    -- Other fields
   );
 
ALTER TABLE CUR_TEMPLATE ADD CONSTRAINT PK_CUR_TEMPLATE PRIMARY KEY (ID_REPORT, ID_TEMPLATE)

-- CUR_TEMPLATE foreign keys
ALTER TABLE CUR_TEMPLATE ADD CONSTRAINT FK_CUR_PLAN_REFERENCE_CUR_REPO FOREIGN KEY (ID_REPORT)
      REFERENCES CUR_REPORTS (ID_REPORT);

第二个表CUR_REPORTS

-- CUR_REPORTS definition
CREATE TABLE CUR_REPORTS 
   (    
    ID_REPORT NUMBER(3,0) NOT NULL, 
    NAME_REPORT VARCHAR2(100) NOT NULL, 
    -- other fields 
    ID_TEMPLATE_DEFAULT NUMBER(5,0), 
    -- other fields
   ) ;

ALTER TABLE CUR_REPORTS ADD CONSTRAINT PK_CUR_REPORTS PRIMARY KEY (ID_REPORT)

ALTER TABLE CUR_REPORTS CONSTRAINT FK_CUR_REPO_REFERENCE_CUR_PLAN FOREIGN KEY (ID_REPORT, ID_TEMPLATE_DEFAULT)
      REFERENCES CUR_TEMPLATE (ID_REPORT, ID_TEMPLATE) 

第一个表CUR_REPORTS实体当前报表

@Entity
@Table(name = "CUR_REPORTS")
@IdClass(CurPlantillaPK.class)
@Getter
@Setter
public class CurReport {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "ID_REPORT", nullable = false)
    private Long id;

    @Column(name = "NAME_REPORT", nullable = false, length = 100)
    private String nombreReporte;

    @ManyToOne(fetch = FetchType.LAZY) <---WHERE IS THE PROBLEM 
    @JoinColumn(name = "ID_REPORT", referencedColumnName = "ID_REPORTE")
    @JoinColumn(name = "ID_TEMPLATE_DEFAULT", referencedColumnName = "ID_TEMPLATE")
    private CurTemplate curTemplate;

    @OneToMany(mappedBy = "curReport")
    private Set<CurTemplate> curTemplates= new LinkedHashSet<>();
}

第二个表CUR_TEMPLATE实体CurReport

@Entity
@Table(name = "CUR_TEMPLATE")
@IdClass(CurPlantillaPK.class)
@Getter
@Setter
public class CurTemplate {
    
    @Id
    @Column(name = "ID_REPORT", nullable = false)
    private Long idReport;

    @Id
    @Column(name = "ID_TEMPLATE", nullable = false)
    private Long idTemplate;

    
    @ManyToOne(optional = false, fetch = FetchType.LAZY)
    @JoinColumn(name = "ID_REPORT", foreignKey = @ForeignKey(name = "FK_CUR_PLAN_REFERENCE_CUR_REPO"), referencedColumnName = "ID_REPORT", insertable = false, updatable = false)
    private CurReport curReport;

}

当我添加可插入=假时，可更新=假

@JoinCollie（name="ID_REPORT"，参考列名="ID_REPORT"，可插入=false，可更新=false）

说

不允许在属性中混合可插入列和不可插入列:CurTemplate

我怎么能映射这些关系？当 FK 的一个字段为 PK 列时，如何解析@JoinColumn？

Answer 1

您可以使用派生的标识并映射 CurTemplate，如下所示：

@Entity
@Table(name = "CUR_TEMPLATE")
@IdClass(CurTemplatePK.class)
@Getter
@Setter
public class CurTemplate {

    @Id
    @Column(name = "ID_TEMPLATE", nullable = false)
    private Long idTemplate;

    @Id
    @ManyToOne(optional = false, fetch = FetchType.LAZY)
    @JoinColumn(name = "ID_REPORT", foreignKey = @ForeignKey(name = "FK_CUR_PLAN_REFERENCE_CUR_REPO"), referencedColumnName = "ID_REPORT", insertable = false, updatable = false)
    private CurReport curReport;

}

然后您将需要一个这样的@IdClass：

public class CurTemplatePK {
    Long idTemplate; // matches name of @Id attribute
    Long curReport; // matches name of @Id attribute and type of CurReport PK
}

然后，您应该为默认模板键使用基本映射，并为默认模板对象提供getter：

@Entity
@Table(name = "CUR_REPORTS")
@IdClass(CurPlantillaPK.class)
@Getter
@Setter
public class CurReport {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "ID_REPORT", nullable = false)
    private Long id;

    @Column(name = "NAME_REPORT", nullable = false, length = 100)
    private String nombreReporte;

    @Column(name = "ID_TEMPLATE_DEFAULT")
    private Long idDefaultTemplate;

    @OneToMany(mappedBy = "curReport")
    private Set<CurTemplate> curTemplates= new LinkedHashSet<>();

    public CurTemplate getDefaultTemplate() {
        return this.curTemplates.stream()
                .filter(template -> template.getIdTemplate().equals(idDefaultTemplate))
                .findFirst()
                .orElse(null);
    {
}

如果您想允许客户端设置默认模板，您将需要实现一个setter，该setter首先验证新的默认模板是否已经在setcurTemplate中。