字段 'index_id' 沒有默認值”在嘗試使用 primary_key 作為 Hibernate 中的復合鍵的一部分時

Question

我正在使用 Hibernate 來更新 MySQL 數據庫中的數據。 我有兩個表索引和屬性，如下所述。

第一個表中的 index_id 不是自動生成的，我正在分配值。

當我嘗試將 index_id 作為屬性表中復合鍵的一部分時，我得到“字段 'index_id' 沒有默認值”。 我可以在 MySQL 中手動插入數據，但我的問題是我無法通過 Hibernate 代碼執行此操作。

CREATE TABLE index (
    index_id BINARY(16),
    index_name VARCHAR(225) NOT NULL ,
    config VARCHAR(255) NOT NULL,

    PRIMARY KEY (index_id)
);

CREATE TABLE properties (
    index_id BINARY(16),
    property_key VARCHAR(225) NOT NULL,
    property_value VARCHAR(225) NOT NULL,

    PRIMARY KEY (index_id, property_key),
    FOREIGN KEY (index_id) REFERENCES index(index_id)  
);

對應的類與 Hibernate 注釋相同。

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;

import java.util.Date;
import java.util.Set;
import java.util.UUID;

import com.sun.istack.NotNull;

@Entity
@Table(name = "index")
public class Index {
    @Id
    @Column(name = "index_id")
    private UUID indexId;

    @Column(name = "index_name")
    private String indexName;

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

    @OneToMany(cascade = CascadeType.ALL)
    @JoinColumn(name = "index_id")
    private Set<Property> properties;

    public Index() {}
}

其他帖子中建議的答案是使用自動生成的值，這不是我想要的。

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
import java.io.Serializable;

@Entity
@Table(name = "properties")
public class Property implements Serializable {
    private static final long serialVersionUID = 1881413500711441951L;

    @Id
    @Column(name = "property_key")
    private String propertyKey;

    @Id
    @Column(name = "property_value")
    private String propertyValue;

    public Property() {}

    public Property(String propertyKey, String propertyValue) {
        this.propertyKey = propertyKey;
        this.propertyValue = propertyValue;
    }
}

hibernate.cfg.xml

<?xml version = "1.0" encoding = "utf-8"?>
<!DOCTYPE hibernate-configuration SYSTEM
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name = "hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <!-- JDBC Database connection settings -->
        <property name="connection.driver_class">com.mysql.cj.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/index?useSSL=false</property>
        <property name="connection.username">###</property>
        <property name="connection.password">###</property>
        <!-- JDBC connection pool settings ... using built-in test pool -->
        <property name="connection.pool_size">1</property>
        <!-- Select our SQL dialect -->
        <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
        <!-- Echo the SQL to stdout -->
        <property name="show_sql">true</property>
        <!-- Set the current session context -->
        <property name="current_session_context_class">thread</property>
        <!-- Drop and re-create the database schema on startup -->
        <property name="hbm2ddl.auto">update</property>
        <!-- dbcp connection pool configuration -->
        <mapping class="com.learning.models.Index" />
        <mapping class="com.learning.models.Property" />
    </session-factory>
</hibernate-configuration>

HibernateUtil.java

import org.hibernate.SessionFactory;
import org.hibernate.boot.Metadata;
import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;

public class HibernateUtil {
    private static StandardServiceRegistry registry;
    private static SessionFactory sessionFactory;
    public static SessionFactory getSessionFactory() {
        if (sessionFactory == null) {
            try {
                // Create registry
                registry = new StandardServiceRegistryBuilder().configure().build();
                // Create MetadataSources
                MetadataSources sources = new MetadataSources(registry);
                // Create Metadata
                Metadata metadata = sources.getMetadataBuilder().build();
                // Create SessionFactory
                sessionFactory = metadata.getSessionFactoryBuilder().build();
            } catch (Exception e) {
                e.printStackTrace();
                if (registry != null) {
                    StandardServiceRegistryBuilder.destroy(registry);
                }
            }
        }
        return sessionFactory;
    }
    public static void shutdown() {
        if (registry != null) {
            StandardServiceRegistryBuilder.destroy(registry);
        }
    }
}

Answer 1

我能夠解決這個問題。 我在索引 class 中給出了一對多的關系

@OneToMany(cascade = CascadeType.ALL)
@JoinColumn(name = "index_id")
private Set<Property> properties;

問題是我必須在屬性 class 中使用 index_id 進行多對一映射。

我將屬性 class 更改如下。

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
import java.io.Serializable;

@Entity
@Table(name = "properties")
public class Property implements Serializable {
    private static final long serialVersionUID = 1881413500711441951L;

    @Id
    @Column(name = "property_key")
    private String propertyKey;

    @Id
    @Column(name = "property_value")
    private String propertyValue;

    @Id
    @ManyToOne
    @JoinColumn(name ="index_id")
    private Index index;

    public Property() {}

    public Property(String propertyKey, String propertyValue, Index index) {
        this.propertyKey = propertyKey;
        this.propertyValue = propertyValue;
        this.index = index;
    }
}