Hibernate数据库映射 [英] Hibernate database mapping
问题描述
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： https://hibernate.onjira.com/browse/HHH-3729 。
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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