hibernate映射视图的两种方式

1.数据库已经建立视图，hibernate只是把视图当作普通的表来映射。

 

视图VIEW_MER_INST_POS:

select MER.DAYS_MERCHT_ID MER_ID, 
       INST.DAYS_MERCHT_ID INST_ID, 
       POS.POS_ID POS_ID 
from tbl_days_mercht_attr MER, 
     tbl_days_mercht_info INST, 
     tbl_days_mercht_pos_info POS 
where MER.days_mercht_id = INST.up_days_mercht_id 
  and INST.days_mercht_id = POS.days_mercht_id

 

 

hbm.xml配置

<class 
    name="db.po.ViewMerInstPos" 
    table="VIEW_MER_INST_POS" 
> 

    <composite-id> 
            <key-property 
            name="merId" 
            column="MER_ID" 
            type="java.lang.String" 
            length="8" 
        /> 
        <key-property 
            name="instId" 
            column="INST_ID" 
            type="java.lang.String" 
            length="8" 
        /> 
        <key-property 
            name="posId" 
            column="POS_ID" 
            type="java.lang.String" 
            length="8" 
        /> 
  </class> 
</hibernate-mapping>

 

 

2.数据库没有视图，用hibernate自己做视图映射

hbm配置如下：

<hibernate-mapping package="huntersxp.db.pojo"> 
<class name="ViewMerInstPos"> 
<meta attribute="sync-DAO">false</meta> 
<subselect> 
select 
MER.DAYS_MERCHT_ID MER_ID,INST.SHOP_NM SHOP_NM,POS.POS_ID POS_ID 
from tbl_days_mercht_attr MER, 
tbl_days_mercht_info INST, 
tbl_days_mercht_pos_info POS 
where MER.days_mercht_id = INST.up_days_mercht_id and INST.days_mercht_id = POS.days_mercht_id 
</subselect> 
<synchronize table="tbl_days_mercht_attr"/> 
<synchronize table="tbl_days_mercht_info"/> 
<synchronize table="tbl_days_mercht_pos_info"/> 
<composite-id> 
        <key-property 
            name="merId" 
            column="MER_ID" 
            type="java.lang.String" 
            length="8" 
        /> 
        <key-property 
            name="shopNm" 
            column="SHOP_NM" 
            type="java.lang.String" 
            length="40" 
        /> 
        <key-property 
            name="posId" 
            column="POS_ID" 
            type="java.lang.String" 
            length="40" 
        /> 
</composite-id> 
</class> 
</hibernate-mapping>

 

其中synchronize表示当表的数据发生变化的时候，视图的数据也会发生变化。