Question

我有2个班级

验证
合同

具有以下结构：

  public class Verification implements Serializable {
     private Long verificationId;
     private Long salesManCode;
     private Long clientCode;
     ...
  }

  public class Contract implements Serializable {
     private Long contractId;
     private Long salesManCode;
     private Long clientCode;
     ...
  }

这些类有各自的hbm.xml映射，在数据库模型中表没有关联，在hibernate映射中都没有，但是在保存契约时，它必须具有相同的verificationId y contractId字段（业务规则），但有些情况下也没有验证合同。

verification
 verificationId | salesManCode | clientCode
  1050              1001            2056
  1051              1001            2248
  1054              1002            2856

contract
 contractId | salesManCode |clientCode
  1050         1001          2056         <- this contract have verification
  1051         1001          2248         <- this contract have verification
  1052         1025          2822         <- this contract not have verification
  1053         1254          1547         <- this contract not have verification
  1054         1002          2856         <- this contract have verification

我的问题是当我运行HQL查询时：

select con.salesManCode,  ver.salesManCode, con.clientCode, ver.clientCode, con.contracId, ver.verificationId 
from Verification ver, Contract con
where ver.verificationId = con.contractId

但是Hibernate使用交叉连接句子进行翻译并组合所有记录。是否有任何方法可以在hbm.xml文件中的不相关类之间执行HQL查询？

RULE：不应该映射实体。

Answer 1

您可以按如下方式映射两个表之间的连接关系：

@Entity
public class Verification implements Serializable {
    private Long verificationId;

    private Long salesManCode;
    private Long clientCode;
    ...
}

@Entity
public class Contract implements Serializable {
    private Long contractId;        

    @MapsId
    @OneToOne
    @JoinColumn(name = "contractId", referencedColumnName = "verificationId")
    private Verification verification;

    private Long salesManCode;
    private Long clientCode;
}

您的查询变为：

select con.salesManCode, ver.salesManCode, con.clientCode, ver.clientCode, con.contracId, ver.verificationId 
from Contract con
join con.verification ver

因此，您可以获得内部联接而不是CROSS JOIN。

HQL Hibernate不相关的实体，但ID相同

1 个答案: