hibernate 继承映射

一，一个类继承体系一张表

 

<discriminator column="type" type="int"/>  <!--缺省：string（hibernate类型）-->

<subclass name="Skiller" discriminator-value="1">  <!--缺省：类的名称-->
    <property name="skill"/>
</subclass>
<subclass name="Sales" discriminator-value="2">
    <property name="sell"/>
</subclass>

 

<joined-subclass name="Skiller" table="skiller">
    <key column="emp_id"/>
    <property name="skill"/>
</joined-subclass>
<joined-subclass name="Sales" table="sales">
    <key column="emp_id"/>
    <property name="sell"/>
</joined-subclass>

 

 

<discriminator column="type" type="int"/>

<subclass name="Skiller" discriminator-value="1">
    <property name="skill"/>
</subclass>		
<subclass name="Sales" discriminator-value="2">
    <join table="sales">
        <key column="emp_id"/>
        <property name="sell"/>
    </join>
</subclass>

 

    主键不能使用native 生成策略，可以使用assigned

<class name="Employee" abstract="true"><!--abstract="true" 将不生产employee这张表-->
          <id name="id">
                         <generator class="assigned"/>
          </id>

 

<union-subclass name="Skiller" table="skiller">
    <property name="skill"/>
</union-subclass>
<union-subclass name="Sales" table="sales">
    <property name="sell"/>
</union-subclass>