Hibernate不会自动创建表 [英] Hibernate does not create tables automatically

问题描述

我有Hibernate和Spring框架的Maven项目。
我希望Hibernate自动创建表，但所有现有的表只是被删除，并且不会创建所需的表。
在会话工厂初始化期间不会抛出任何异常，但是当我尝试保存 Player 实体时，抛出异常：

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：表'billboarddb.player'不存在

如果我手动创建表并将属性 hibernate.hbm2ddl.auto 更改为validate，那么一切正常。
你有什么想法，为什么Hibernate不创建表？

Spring配置文件：

 < context：component-scan base-package =org.meluk.billboard.business.controller/> 
< tx：annotation-driven transaction-manager =txManager/> 
< bean id =propertyConfigurerclass =org.springframework.beans.factory.config.PropertyPlaceholderConfigurer> 
< property name =locations> 
< list> 
<值> /WEB-INF/config/jdbc.properties< /值> 
< / list> 
< / property> 
< / bean> 
< bean id =dataSourceclass =org.springframework.jdbc.datasource.DriverManagerDataSource> 
< property name =driverClassNamevalue =$ {hibernate.connection.driver_class}/> 
< property name =urlvalue =$ {hibernate.connection.url}/> 
< property name =usernamevalue =$ {hibernate.connection.username}/> 
< property name =passwordvalue =$ {hibernate.connection.password}/> 
< / bean> 
< bean id =sessionFactoryclass =org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean> 
< property name =dataSourceref =dataSource/> 
< property name =configLocationvalue =/ WEB-INF / hibernate.cfg.xml/> 
< property name =packagesToScanvalue =org.meluk.billboard.jpa/> 
< property name =hibernateProperties> 
<道具> 
< prop key =hibernate.dialect> $ {hibernate.dialect}< / prop> 
< prop key =hibernate.show_sql> $ {hibernate.show_sql}< / prop> 
< prop key =hibernate.hbm2ddl.auto> $ {hibernate.hbm2ddl.auto}< / prop> 
< prop key =hibernate.c3p0.min_size> $ {hibernate.c3p0.min_size}< / prop> 
< prop key =hibernate.c3p0.max_size> $ {hibernate.c3p0.max_size}< / prop> 
< prop key =hibernate.c3p0.timeout> $ {hibernate.c3p0.timeout}< / prop> 
< prop key =hibernate.c3p0.max_statements> $ {hibernate.c3p0.max_statements}< / prop> 
< /道具> 
< / property> 
< / bean> 
 
< bean id =txManagerclass =org.springframework.orm.hibernate3.HibernateTransactionManager> 
< property name =sessionFactoryref =sessionFactory/> 
< / bean> 
  

jdbc.properties文件：

  hibernate.connection.driver_class = com.mysql.jdbc.Driver 
 hibernate.connection.url = jdbc：mysql：//127.0.0.1：3306 / BillboardDB 
 hibernate.connection.username = root 
 hibernate.connection.password = 1234 
 hibernate.default_schema = BillboardDB 
 hibernate.dialect = org.hibernate.dialect.MySQLInnoDBDialect 
 hibernate.hbm2ddl.auto =创建
 hibernate.show_sql = true 
 hibernate.c3p0.min_size = 5 
 hibernate.c3p0.max_size = 20 
 hibernate.c3p0.timeout = 1800 
 hibernate.c3p0.max_statements = 50 
  

Hibernate依赖关系：

 < dependency> 
< groupId> org.hibernate< / groupId> 
< artifactId> hibernate-entitymanager< / artifactId> 
< version> $ {hibernateVersion}< / version> 
< /依赖关系> 
< dependency> 
< groupId> org.hibernate< / groupId> 
< artifactId> hibernate-c3p0< / artifactId> 
< version> $ {hibernateVersion}< / version> 
< /依赖关系> 
< dependency> 
< groupId> org.hibernate< / groupId> 
< artifactId> hibernate-tools< / artifactId> 
< version> $ {hibernateToolsVersion}< / version> 
< /依赖关系> 
  

解决方案

我解决了这个问题。 Hibernate无法使用MysqlInnoDBDialect创建表。
现在我改用MySQL5InnoDBDialect。

I have Maven project with Hibernate and Spring framework. I want Hibernate to create tables automatically, but all existing tables are just dropped and the required tables are not created. No exceptions are thrown during session factory initialization, but when I try save a Player entity, exception is thrown:

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'billboarddb.player' doesn't exist

If I create the tables manually and change the property hibernate.hbm2ddl.auto to "validate", then everything works fine. Do you have any idea, why Hibernate does not create the tables?

Spring configuration file:

<context:component-scan  base-package="org.meluk.billboard.business.controller" />
<tx:annotation-driven transaction-manager="txManager" />
<bean id="propertyConfigurer"  class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="locations" >
        <list>
            <value>/WEB-INF/config/jdbc.properties</value>
        </list>
    </property>
</bean>
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="${hibernate.connection.driver_class}" />
    <property name="url" value="${hibernate.connection.url}" />
    <property name="username" value="${hibernate.connection.username}" />
    <property name="password" value="${hibernate.connection.password}" />
</bean>
<bean id="sessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean" >
    <property name="dataSource" ref="dataSource" />
    <property name="configLocation" value="/WEB-INF/hibernate.cfg.xml" />
    <property name="packagesToScan" value="org.meluk.billboard.jpa" />
    <property name="hibernateProperties">
        <props>
            <prop key="hibernate.dialect">${hibernate.dialect}</prop>
            <prop key="hibernate.show_sql">${hibernate.show_sql}</prop>
            <prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}</prop>
            <prop key="hibernate.c3p0.min_size">${hibernate.c3p0.min_size}</prop>
            <prop key="hibernate.c3p0.max_size">${hibernate.c3p0.max_size}</prop>
            <prop key="hibernate.c3p0.timeout">${hibernate.c3p0.timeout}</prop>
            <prop key="hibernate.c3p0.max_statements">${hibernate.c3p0.max_statements}</prop>
        </props>
    </property>
</bean>

<bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
    <property name="sessionFactory" ref="sessionFactory" />
</bean>

jdbc.properties file:

hibernate.connection.driver_class=com.mysql.jdbc.Driver
hibernate.connection.url=jdbc:mysql://127.0.0.1:3306/BillboardDB
hibernate.connection.username=root
hibernate.connection.password=1234
hibernate.default_schema=BillboardDB
hibernate.dialect=org.hibernate.dialect.MySQLInnoDBDialect
hibernate.hbm2ddl.auto=create
hibernate.show_sql=true
hibernate.c3p0.min_size=5
hibernate.c3p0.max_size=20
hibernate.c3p0.timeout=1800
hibernate.c3p0.max_statements=50

Hibernate dependencies:

<dependency>
  <groupId>org.hibernate</groupId>
  <artifactId>hibernate-entitymanager</artifactId>
  <version>${hibernateVersion}</version>
</dependency>
<dependency>
  <groupId>org.hibernate</groupId>
  <artifactId>hibernate-c3p0</artifactId>
  <version>${hibernateVersion}</version>
</dependency>
<dependency>
  <groupId>org.hibernate</groupId>
  <artifactId>hibernate-tools</artifactId>
  <version>${hibernateToolsVersion}</version>
</dependency>

解决方案

I solve the problem. Hibernate could not create tables with MysqlInnoDBDialect. Now I use MySQL5InnoDBDialect instead.

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