Hibernate不会自动创建数据库中不存在的表 [英] Hibernate is not auto-creating a table that does not exist in the DB

问题描述

我有一个基本的Hibernate代码，
我已经将属性设置为hibernate.hbm2ddl.auto作为更新，但它不会自动创建数据库中的表。

这些是必需的文件：

employee.hbm.xml

 < hibernate-mapping> 
< class name =contacts.employeetable =contacts> 
< meta attribute =class-description>< / meta> 
< id column =contactIdname =contactIdtype =string> 
< generator class =assigned/> 
< / id> 
< property column =contactNamelength =100name =contactNamenot-null =truetype =string/> 
< property column =passwordlength =100name =passwordnot-null =truetype =string/> 
 < key column =contactId/> 
  
< / set> 
 
< / class> 
< / hibernate-mapping> b 
 
 
 $ b 
 p> <休眠映射> 
< class name =contacts.responsibilitiestable =responsibilities> 
< meta attribute =class-description> 
如果雇员为
< / meta> 
 < generator class =increment/> 
< / id> 
 < / class> 
< / hibernate-mapping> 
  

hibernate.cfg.xml

 <冬眠-结构> 
< session-factory> 
< property name =hibernate.dialect> org.hibernate.dialect.MySQLInnoDBDialect< / property> 
< property name =hibernate.connection.driver_class> com.mysql.jdbc.Driver< / property> 
< property name =hibernate.connection.url> jdbc：mysql：// localhost：3306 / ****< / property> 
< property name =hibernate.connection.username> *****< / property> 
< property name =hibernate.connection.password> *****< / property> 
< property name =hibernate.hbm2ddl.auto>更新< / property> 
< property name =hibernate.show_sql> true< / property> 
< mapping resource =contacts / employee.hbm.xml/> 
< mapping resource =contacts / responsibilitiy.hbm.xml/> 
< / session-factory> 
< / hibernate-configuration> 
  

这是我尝试运行的Main.java：

  public class Main {
 
 public static void main（String [] args）{
 
 SessionFactory sessionfactory = NewHibernateUtil.getSessionFactory（）; 
交易交易=空; 
尝试{
 Session session = sessionfactory.openSession（）; 
 transaction = session.beginTransaction（）; 
设定<责任> groups = new HashSet< responsibilities>（）; 
责任responsibilityOne =新职责（Java）; 
责任responsibilityTwo =新职责（SQL）; 
责任responsibilityThree =新职责（Oracle）; 
 groups.add（responsibility）; 
 groups.add（responsibility）; 
 groups.add（responsibility）; 
 String uuid = UUID.randomUUID（）。toString（）; 
字符串uuid2 = UUID.randomUUID（）。toString（）; 
雇员firstEmployee; 
 firstEmployee =新员工（uuid，Mike，groups）; 
员工secondEmployee =新员工（uuid2，Marc，groups）; 
 session.save（responsibility）; 
 session.save（responsibility）; 
 session.save（responsibility）; 
 session.save（firstEmployee）; 
 session.save（secondEmployee）; 
 
 transaction.commit（）; 
} catch（HibernateException e）{
 transaction.rollback（）; 
 e.printStackTrace（）; 
}终于{b 
 $ b} 
 
} 
} 
  

这是我得到的错误：



com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException：Table' * *。职责'不存在

解决方案

我有同样的问题， p>



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




I have a basic Hibernate code, I have set the property "hibernate.hbm2ddl.auto" as update still it is not auto-creating the table in the Database.

These are the required files:

employee.hbm.xml

<hibernate-mapping>
  <class name="contacts.employee" table="contacts">
      <meta attribute="class-description"></meta>
    <id column="contactId" name="contactId" type="string">
      <generator class="assigned"/>
    </id>
    <property column="contactName" length="100" name="contactName" not-null="true" type="string"/>
    <property column="password" length="100" name="password" not-null="true" type="string"/>
    <set cascade="all" name="groupOfResponsibilities" table="employee_responsibilty">
      <key column="contactId"/>
      <many-to-many class="contacts.responsibilities" column="responsibilityId"/>

    </set>

  </class>
</hibernate-mapping>

responsibility.hbm.xml

<hibernate-mapping>
  <class name="contacts.responsibilities" table="responsibilities">
    <meta attribute="class-description">
        This class list of responsibilities if an employee
    </meta>
    <id column="responsibilityId" name="responsibilityId" type="long">
      <generator class="increment"/>
    </id>
    <property column="responsibilityName" name="responsibilityName" type="string"/>
  </class>
</hibernate-mapping>

hibernate.cfg.xml

<hibernate-configuration>
  <session-factory>
    <property name="hibernate.dialect">org.hibernate.dialect.MySQLInnoDBDialect</property>
    <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
    <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/****</property>
    <property name="hibernate.connection.username">*****</property>
    <property name="hibernate.connection.password">*****</property>
    <property name="hibernate.hbm2ddl.auto">update</property>
    <property name="hibernate.show_sql">true</property>
    <mapping resource="contacts/employee.hbm.xml"/>
    <mapping resource="contacts/responsibilitiy.hbm.xml"/>
  </session-factory>
</hibernate-configuration>

This is the Main.java that I am trying to run:

public class Main {

    public static void main(String[] args) {

        SessionFactory sessionfactory = NewHibernateUtil.getSessionFactory();
        Transaction transaction = null;
        try {
            Session session = sessionfactory.openSession();
            transaction = session.beginTransaction();
            Set<responsibilities> groups = new HashSet<responsibilities>();
            responsibilities responsibilityOne=new responsibilities("Java");
            responsibilities responsibilityTwo=new responsibilities("SQL");
            responsibilities responsibilityThree=new responsibilities("Oracle");
            groups.add(responsibilityOne);
            groups.add(responsibilityTwo);
            groups.add(responsibilityThree);
            String uuid = UUID.randomUUID().toString();
            String uuid2 = UUID.randomUUID().toString();
            employee firstEmployee;
            firstEmployee = new employee(uuid, "Mike", groups);
            employee secondEmployee = new employee(uuid2, "Marc", groups);
            session.save(responsibilityOne);
            session.save(responsibilityTwo);
            session.save(responsibilityThree);
            session.save(firstEmployee);
            session.save(secondEmployee);

            transaction.commit();
        } catch (HibernateException e) {
            transaction.rollback();
            e.printStackTrace();
        } finally {

        }

    }
}

This is the error that I get:

com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table '**.responsibilities' doesn't exist

解决方案

I had the same issue, this worked for me -

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

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