<class name="com.subex.models.Issues" table="ISSUES">

  <id name="id" type="integer" column="id" >
     <generator class="native"/>
     <param name="sequence">ISSUES_Seq</param>
  </id>

     <property name="brief" type="string" column="brief"/>
    <property name="description" type="string" column="description"/>
    <property name="module" type="string" column="module"/>
    <property name="version" type="string" column="version"/>
    <property name="site" type="string" column="site"/>
    <property name="posted_by" type="string" column="posted_by"/>
</class>

<id name="id" type="integer" column="id" >
   <generator class="native"/>                <!-- 1 -->
   <param name="sequence">ISSUES_Seq</param>  <!-- 2 -->
</id>

<id name="id" type="integer" column="id" >
 <generator class="native">
     <param name="sequence">ISSUES_Seq</param>
 <generator>
</id>

<id name="id" type="integer" column="id" >
 <generator class="sequence">
     <param name="sequence">ISSUES_Seq</param>
 <generator>
</id>

**error**:**The content of element type "property" must match "(meta*,(column|formula)*,type?)".**


<!DOCTYPE hibernate-mapping PUBLIC
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">


<hibernate-configuration>
    <session-factory>
        <property name="connection.driver_class">
            com.mysql.jdbc.Driver
        </property>
        <property name="connection.url">
            jdbc:mysql://localhost:3306/test
        </property>

        <property name="connection.username">
            root
        </property>
        <property name="connection.password">
            root
        </property>
        <property name="connection.pool_size">
            10
        </property>

        <property name="dialect">
            org.hibernate.dialect.MySQLDialect
        </property>
        <property name="hbm2ddl.auto">
            create
        </property>
        <property name="show_sql">
            true
        </property>

        <mapping resource="resources/student.hbm.xml" />

    </session-factory>
</hibernate-configuration>

Could you please assist?