Question

i search the web for answer, but all the answers refer to composite id PK. i want two map two columns of type long to PK. one should be regular generated id, and the other should be regular long field.

i 绘制以下地图:

  <class name="com.company.MyTable" table="My_Table">
        <id name="id" column="id">            
            <generator class="assigned"/>
        </id>
        <property name="jobId" column="job_id" type="long" index="oes_job_id_idx" />
        <property name="serverId" column="server_id" type="long"/>
     </class>

i want to add to the PK the job_id column. how do i do that?

Answer 1

Primary keys, by definition should be the unique key with the fewest columns possible:

your can t have multiple primary keys
you shouldn t use an additional column for the primary key, if the first column is already unique

这实际上没有给你带来好处,无法建立一个单独的指数——从而把生成的实地作为主要的关键。因此,藏匿不支持,因为这样做是错误的。

Answer 2

请看这一问题,综合解决办法是否充分。主要要点:

制图同级关系

之后

绘制同级关系图—— 继续

希望会有所助益。

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