小编Vis*_*uri的帖子

我正在使用Spring mvc Web应用程序,我需要使用Hibernate创建一个城镇.以下是我的城镇模型.

@Entity
@Table(name="town")
public class TownModel {

    @Id
    @Column(name="townid")
    @GeneratedValue 
    private Integer townId;

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

    @Column(name="desc")
    private String townDesc;

    @ManyToOne(optional = true)
    @JoinColumn(name="districtid")
    private DistrictModel districtModel;
}

我有另一个名为district的实体.城镇是区的一部分,一个区可以有多个城镇.以下是我的区域模型:

@Entity
@Table(name="district")
public class DistrictModel {

    @Id
    @Column(name="districtid")
    @GeneratedValue
    private Integer districtId;

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

    @Column(name="desc")
    private String description;

    @OneToMany(mappedBy = "districtModel", fetch = FetchType.EAGER)
    @Fetch(value = FetchMode.SUBSELECT)
    private List<TownModel> townModelList;
}

我正在使用以下Hibernate代码来保存城镇:

Session session = sessionFactory.getCurrentSession();
session.save(townModel);

但它显示错误:

21:22:08,104 WARN  [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (http--127.0.0.1-9090-1) SQL Error: 1064, SQLState: …

我正在使用 Hibernate 开发 Spring MVC 应用程序。以下是我的调度程序 servlet 代码：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd
                    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd     
                    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
                    http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd"> 

    <mvc:annotation-driven/>
    <mvc:resources mapping="/resources/**" location="/resources/" />
    <context:component-scan base-package="com.example.abc" />
    <tx:annotation-driven/>
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <property name="suffix" value=".jsp"/>
    </bean>
    <bean id="jndiDataSource" class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName" value="java:/MySqlDS" />
    </bean>
    <bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
        <property name="dataSource" ref="jndiDataSource" />
        <property name="packagesToScan" value="com.example.abc"></property>
    </bean>
    <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory"></property>
    </bean>
</beans>

我没有任何 Hibernate 配置文件，因为 Hibernate 映射是在模型类中完成的。我需要打印从 Hibernate …

我有一个表,我需要在现有列上添加外键.以下是创建表:

CREATE TABLE `itemtx` (
  `itemTxid` int(11) NOT NULL AUTO_INCREMENT,
  `itemcode` varchar(1) NOT NULL,
  `weight` decimal(7,3) DEFAULT NULL,
  `txtype` varchar(10) DEFAULT 'Pickup',
  `tripstopid` int(11) NOT NULL,
  `barcode` varchar(25) DEFAULT NULL,
  `bagcount` int(11) DEFAULT '1',
  PRIMARY KEY (`itemTxid`)
) ENGINE=InnoDB AUTO_INCREMENT=33524 DEFAULT CHARSET=latin1

我需要在tripstopid列上添加外键.我不能删除或清空表,因为它包含数据.以下是引用的表:

CREATE TABLE `tripstop` (
  `tripstopid` int(11) NOT NULL AUTO_INCREMENT,
  `tripid` int(11) DEFAULT NULL,
  `locationName` varchar(100) DEFAULT NULL,
  `userName` varchar(100) DEFAULT NULL,
  `locationid` int(11) DEFAULT NULL,
  `datetime` varchar(20) DEFAULT NULL,
  `createts` varchar(20) DEFAULT NULL,
  `latitude` double DEFAULT NULL, …