Hibernate数据库映射

问题描述

首先，我对Hibernate有点新鲜。要了解我在一个项目中使用它的技术。我尝试映射以下数据库：

 广告系列
 campaignId（+）
名称
 
促销
 campaignId（+）
折扣（+）
产品
消息
  

我在两种情况下都用（+）表示了主键。 Promotion中的'campaignId'是Campaign建立1：m映射模型的外键（一个Campaign有许多促销活动）。使用注释我坚持如何做到这一点。

我并不想在Promotion表中添加promotionId，因为它处理数据繁琐。这当然会使桥接表有点棘手。我也遇到了使用外键的问题，外键也是主键的一部分。

映射是否可能？

---

好的，我得到了它的工作。有点。必须检查持久性是否真的有效。我做了以下工作：

  @Entity 
 @Table（name =CAMPAIGNS）
 @Audited 
 public class CampaignEntity {
 private int campaignId; 
私人字符串名称; 
私人列表< PromotionEntity>促销; 
 
 public CampaignEntity（int campaignId，String name）{
 this.campaignId = campaignId; 
 this.name = name; 
 
 $ b @Id 
 @GeneratedValue（strategy = GenerationType.IDENTITY）
 @Column（name =cmp_id）
 public int getCampaignId（） {
 return campaignId; 
} 
 
 public void setCampaignId（int campaignId）{
 this.campaignId = campaignId; 
} 
 
 //此处的广告系列名称...省略以节省空间
 
 @OneToMany 
 @JoinColumn（name =cmp_id）
公开列表< PromotionEntity> getPromotions（）{
退货促销; 
} 
 
 public void setPromotions（List< PromotionEntity> promotions）{
 this.promotions = promotions; 
 
 
 
 
 
 
 
促销是一种香草映射（根本不使用嵌入式），字段为：campaignId，折扣，消息。 （它也没有@ManyToOne批注。）
 
 
 
是否有意义？
 
 
 
最后，这将是一等奖：你可以看到我正在使用Envers来审计整个事情。上面创建了一个相当丑陋的CampaignEntity_PromotionEntity_AUD表。我知道这是必要的，但我怎么能将它重命名为CAMPAIGN_PROMOTION_AUD？
 
 
谢谢你们！
 
 
 
 
 
 
我在一个孤独的网站上得到了一个答案，这个网站深深地隐藏在Hibernate的Jira错误跟踪网站的远端：。 
 
 
答案是当然使用@AuditJoinTable（name =CAMPAIGN_PROMOTION_AUD）。 
解决方案
这就是我现在使用的。它运作良好，Hibernate为我处理促销活动的PK。  
 
 
  @Entity 
 @Table（name =CAMPAIGNS）
 @Audited 
 public class CampaignEntity {
 
 @Id 
 @GeneratedValue（strategy = GenerationType.IDENTITY）
 @Column（name =id，nullable = false）
私人整数campaignId; 
 
 @Column（name =name，nullable = false，unique = true）
 private String campaignName; 
 
 @OneToMany（cascade = CascadeType.ALL，orphanRemoval = true）
 @JoinTable（name =CAMPAIGN_PROMOTIONS，
 joinColumns = {@JoinColumn（name =campaign_id）） }，
 inverseJoinColumns = {@JoinColumn（name =promotion_id）}）
 private设置< PromotionEntity>促销; 
 
 ... 
} 
  
然后，PromotionEntity：  
 
 
  @Entity 
 @Table（name =PROMOTIONS）
 @Audited 
 public类PromotionEntity实现了Comparable< PromotionEntity> {
 
 @Id 
 @GeneratedValue（strategy = GenerationType.IDENTITY）
 private Integer id; 
 
 @Column（name =discount，nullable = false）
私人整数折扣; 
 
 @Column（name =message，nullable = false）
 private String message; 
 
 ... 
} 
  
我也喜欢注释而不是getter，因为它更紧凑，读起来更容易。
 
Firstly, I am somewhat new with Hibernate.  To get to know the technology I am using it in a project.  I am trying to map the following database:
Campaign
  campaignId(+)
  name

Promotion
  campaignId(+)
  discount(+)
  product
  message
I've indicated the primary key in both cases with a (+).  The 'campaignId' in Promotion is a foreign key to Campaign to model the 1:m mapping (A Campaign has many Promotions).  Using annotations I am stuck on how to do this.  
I do not really want to add a promotionId in the Promotion table as it makes working with the data cumbersome.  This of course, makes the bridging table a bit tricky.  I also have problems working with a foreign key that is also part of the primary key.
Is a mapping for this possible at all?
Ok, I got it working.  Sort of.  Have to check if persistence actually work.  I did the following:
@Entity
@Table(name = "CAMPAIGNS")
@Audited
public class CampaignEntity {
    private int campaignId;
    private String name;
    private List<PromotionEntity> promotions;

    public CampaignEntity(int campaignId, String name) {
        this.campaignId = campaignId;
        this.name = name;
    }

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "cmp_id")
    public int getCampaignId() {
        return campaignId;
    }

    public void setCampaignId(int campaignId) {
        this.campaignId = campaignId;
    }

    // Campaign name here... left out to save space

    @OneToMany
    @JoinColumn(name = "cmp_id")
    public List<PromotionEntity> getPromotions() {
        return promotions;
    }

    public void setPromotions(List<PromotionEntity> promotions) {
        this.promotions = promotions;
    }
}
Promotion is a vanilla mapping (not using embedded after all), with the fields: campaignId, discount, message. (It also does not have a @ManyToOne annotation.)
Does that make sense?
Lastly, and this will be first prize: as you can see I'm using Envers to audit the whole thing.  The above creates a rather ugly "CampaignEntity_PromotionEntity_AUD" table.  I understand that it is needed, but how can I rename it to CAMPAIGN_PROMOTION_AUD rather?
Thanks guys!
I got an answer on a lonely website deeply hidden away in far-corners of the Hibernate's Jira error tracking website: https://hibernate.onjira.com/browse/HHH-3729.
The answer is to use @AuditJoinTable(name = "CAMPAIGN_PROMOTION_AUD") of course. 
 解决方案 
This is what I am now using.  It works well and Hibernate handles the PKs of the Promotions for me.  Thanks again.
@Entity
@Table(name = "CAMPAIGNS")
@Audited
public class CampaignEntity {

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

    @Column(name = "name", nullable = false, unique = true)
    private String campaignName;

     @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true)
     @JoinTable(name = "CAMPAIGN_PROMOTIONS",
                joinColumns = { @JoinColumn(name = "campaign_id") },
                inverseJoinColumns = { @JoinColumn(name = "promotion_id") })
     private Set<PromotionEntity> promotions;

     ...
}
and then, PromotionEntity:
@Entity
@Table(name = "PROMOTIONS")
@Audited
public class PromotionEntity implements Comparable<PromotionEntity> {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;

    @Column(name = "discount", nullable = false)
    private Integer discount;

    @Column(name = "message", nullable = false)
    private String message;

    ...
}
I also prefer annotating the fields rather than the getters as it is more compact and reads easier.
                        
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