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Java 从hibernate映射文件生成DDL_Java_Database_Hibernate Mapping - Fatal编程技术网

Java 从hibernate映射文件生成DDL

Java 从hibernate映射文件生成DDL,java,database,hibernate-mapping,Java,Database,Hibernate Mapping,下面的hibernate映射文件按预期生成java类和DEPARTMENT表,但它没有在DB中创建DPT_教师表,为什么不呢 <hibernate-mapping> <class name="hibernate.Department" table="DEPARTMENT"> <id name="id" column="ID"> <generator class="native"/> &

下面的hibernate映射文件按预期生成java类和DEPARTMENT表,但它没有在DB中创建DPT_教师表,为什么不呢

<hibernate-mapping>
    <class name="hibernate.Department" table="DEPARTMENT">
        <id name="id" column="ID">
            <generator class="native"/>
        </id>
        <property name="subject" column="SUBJECT" type="string"/>

        <set name="teachers" table="DPT_TEACHERS">
            <key column="ID"/>
            <one-to-many class="hibernate.Teacher"/>
        </set>
    </class>
</hibernate-mapping>

您需要添加属性

hibernate.hbm2ddl.auto

使用hibernate.cfg.xml中的数据库连接属性自动创建模式

<property name="hibernate.hbm2ddl.auto">create</property>

 <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost/Test?createDatabaseIfNotExist=true</property>
<property name="connection.username">root</property>
<property name="connection.password"></property>
<property name="connection.pool_size">10</property>
创建
com.mysql.jdbc.Driver
jdbc:mysql://localhost/Test?createDatabaseIfNotExist=true
根
10
table=“DPT\U教师”不是必需的。不需要另一个表来创建1:N关系。key column=“ID”容易混淆,它应该是key column=“TEACHER\u ID”,以便可以作为1:N关系添加到TEACHER表中