JPA 2.1 / Hibernate 5.0 生成模式忽略 inverseJoinColumn 中的 foreignKey 名称答案

【问题标题】：JPA 2.1 / Hibernate 5.0 Generating schema ignores foreignKey name in inverseJoinColumnJPA 2.1 / Hibernate 5.0 生成模式忽略 inverseJoinColumn 中的 foreignKey 名称
【发布时间】：2016-03-14 11:46:09
【问题描述】：

我尝试使用 JPA 2.1 和 Hibernate 5.0 生成 DDL，但不知何故我做错了，它忽略了 inverseJoinColumn 定义中的外键名称。

这些是我的实体：

家长：

@Entity
@Table(name = "PARENT", indexes = { @Index(columnList = "NAME", name = "IDX_NAME") }, uniqueConstraints = { @UniqueConstraint(columnNames = "NAME", name = "UK_NAME") })
@SequenceGenerator(allocationSize = 1, name = "PARENT_ID_GENERATOR", sequenceName = "PARENT_ID_SEQ")
public class Parent {

  @Id
  @GeneratedValue(generator = "PARENT_ID_GENERATOR", strategy = SEQUENCE)
  @Column(name = "ID")
  private Long id;

  @Column(name = "NAME")
  private String name;

  @OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
  @JoinTable(name = "PARENT_CHILD", joinColumns = @JoinColumn(name = "PARENT_ID"), foreignKey = @ForeignKey(name ="FK_PARENT_CHILD_PARENT"), inverseJoinColumns = @JoinColumn(name = "CHILD_ID", foreignKey = @ForeignKey(name ="FK_ABC")), uniqueConstraints = {@UniqueConstraint(columnNames = "CHILD_ID", name = "UK_CHILD_ID") })
  private List<Child> children = new ArrayList<>();

}

孩子：

@Entity
@Table(name = "CHILD", indexes = { @Index(columnList = "NAME", name = "IDX_NAME") }, uniqueConstraints = { @UniqueConstraint(columnNames = "NAME", name = "UK_NAME") })
@SequenceGenerator(allocationSize = 1, name = "CHILD_ID_GENERATOR", sequenceName = "CHILD_ID_SEQ")
public class Child {

  @Id
  @GeneratedValue(generator = "CHILD_ID_GENERATOR", strategy = SEQUENCE)
  @Column(name = "ID")
  private Long id;

  @Column(name = "NAME")
  private String name;
}

我写了下面的小主类来生成ddl

架构创建者：

public class SchemaCreator {

    public static void main(String[] args) throws IOException {
        execute("default", "./target/create.sql");
        System.exit(0);
    }

    public static void execute(String persistenceUnitName, String destination) {
        System.out.println("Generating DDL create script to : " + destination);

        final Properties persistenceProperties = new Properties();

        persistenceProperties.setProperty(org.hibernate.cfg.AvailableSettings.HBM2DDL_AUTO, "");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_DATABASE_ACTION, "none");

        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_SCRIPTS_ACTION, "create");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_CREATE_SOURCE, "metadata");
        persistenceProperties.setProperty(AvailableSettings.SCHEMA_GEN_SCRIPTS_CREATE_TARGET, destination);
        persistenceProperties.setProperty(AvailableSettings.JDBC_DRIVER,"org.h2.Driver");
        persistenceProperties.setProperty(AvailableSettings.JDBC_URL,"jdbc:h2:mem:jpaschema");
        Persistence.generateSchema(persistenceUnitName, persistenceProperties);
    }

}

我的 persistence.xml 看起来像这样

坚持

<persistence xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.1"
         xmlns="http://xmlns.jcp.org/xml/ns/persistence"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence
                            http://java.sun.com/xml/ns/persistence/persistence_2_1.xsd">
<persistence-unit name="default">

    <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>

    <class>nl.generate.ddl.example.Child</class>
    <class>nl.generate.ddl.example.Parent</class>
</persistence-unit>

有人能指出我正确的方向吗？我在github上的一个示例项目中包含了上面的代码https://github.com/vdmc/generate-ddl-example.git

【问题讨论】：

JPA 模式注释对我来说都很好，唯一的例外是某些数据存储会反对名称为“IDX_NAME”的多个索引（一个在父级中，一个在子级中），因为它们的命名空间是全球性的。如果您的 JPA 提供者没有选择 FK 名称，则在其上提出错误。
感谢您的回复。我更改了示例项目中的索引名称。我知道在 Hibernate 4 中存在与此相关的错误，但我也读到他们关闭了这些票证并将它们标记为在 Hibernate 5 中已解决。
酷谢谢。我也会把它带到 Hibernate 中。

标签： java hibernate jpa ddl

【解决方案1】：

实际上，在您的元数据中不正确的一件事是，@JoinTable 上有 "inverseForeignKey"。在那里而不是在 "inverseJoinColumns" 下指定您的 FK 信息。

@JoinTable(name = "PARENT_CHILD", 
    joinColumns = @JoinColumn(name = "PARENT_ID"), 
    foreignKey = @ForeignKey(name ="FK_PARENT_CHILD_PARENT"), 
    inverseJoinColumns = @JoinColumn(name = "CHILD_ID"), 
    inverseForeignKey = @ForeignKey(name ="FK_ABC"), 
    uniqueConstraints = {@UniqueConstraint(columnNames = "CHILD_ID", name = "UK_CHILD_ID") })

【讨论】：