JPA/eclipse-link 2.6.0/mysql：生成的 table 名称不正确

Question

我创建了两个表：

@Entity
@Table(name="instanceOfClass")
public class InstanceOfClass {
(...)
    @OneToMany(fetch=FetchType.LAZY)
    public List<InstanceOfDataProperty> getDataProperties() {
        return dataProperties;
    }
(...)
}

和

@Entity
@Table(name="instanceOfDataProperty")
public class InstanceOfDataProperty  {
    (...)
    @ManyToOne(optional=false,fetch=FetchType.LAZY) 
    @JoinColumn(referencedColumnName="instance_id", nullable=false, updatable=false)
    public InstanceOfClass getInstance()
        {
        return this.instance;
        }
    (...)
 }

调用 getDataProperties() 时，我在日志中收到以下错误

Call: SELECT t1.id, t1.smallContent, t1.VALUE, t1.INSTANCE_id,t1.prop_id, t1.LARGECONTENT_id FROM instanceOfClass_instanceOfDataProperty t0, instanceOfDataProperty t1 WHERE ((t0.InstanceOfClass_id = ?) AND (t1.id = t0.dataProperties_id)) bind => [1 parameter bound]
Query: ReadAllQuery(name="file:/path/to/WEB-INF/classes/_jdbc/mydao" referenceClass=InstanceOfDataProperty sql="SELECT t1.id, t1.smallContent, t1.VALUE, t1.INSTANCE_id, t1.prop_id, t1.LARGECONTENT_id FROM instanceOfClass_instanceOfDataProperty t0, instanceOfDataProperty t1 WHERE ((t0.InstanceOfClass_id = ?) AND (t1.id = t0.dataProperties_id))")

(....) 原因：com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：Table 'user_me.instanceOfClass_instanceOfDataProperty' 不存在

这个user_me.instanceOfClass_instanceOfDataProperty从哪里来的？我该如何解决这个问题？

Answer 1

我认为您必须在 InstanceOfClass 实体中为 @OneToMany 注释使用 mappedBy 值，如下所示：

@Entity
@Table(name="instanceOfClass")
public class InstanceOfClass {
(...)
    @OneToMany(fetch=FetchType.LAZY, mappedBy="instanceOfClass")
    public List<InstanceOfDataProperty> getDataProperties() {
        return dataProperties;
    }
(...)
}

其中 instanceOfClass 应该是 InstanceOfDataProperty class.

中 getter 的名称

来自 JavaEE7 pdf，第 37.1.5.1 章：

Bidirectional relationships must follow these rules.

The inverse side of a bidirectional relationship must refer to its owning side by using the mappedBy element of the @OneToOne, @OneToMany, or @ManyToMany annotation.

The mappedBy element designates the property or field in the entity that is the owner of the relationship. The many side of many-to-one bidirectional relationships must not define the mappedBy element. The many side is always the owning side of the relationship.

我用实体 Person 和 Address (1:N) 进行了快速测试。首先，我省略了 mappedBy，并创建了一个名为 Person_Address 的 table。添加 mappedBy 后，创建了 table Address。

JPA/eclipse-link 2.6.0/mysql：生成的 table 名称不正确

JPA / eclipse-link 2.6.0 / mysql : incorrect generated table name

java

mysql

jpa

eclipselink