将地图映射到与其在Hibernate中的类相同的表

Question

I have a rather simple (I think) class that I want to map:

<class name="parent" table="PARENT_TABLE">
    <composite-id>
        <key-property name = "a" column = "A"/>
        <key-property name = "b" column = "B"/>
        <key-property name = "c" column = "C"/>
    </composite-id>
    <map name = "theMap" table = "PARENT_TABLE" where="type='access'">
        <key foreign-key = "PARENT_TABLE_FK">
            <column name = "A"/>
            <column name = "B"/>
            <column name = "C"/>
        </key>
        <map-key column = "X" type = "double"/>
        <element column = "Y" type = "double" not-null="true"/>
    </map>
</class>

I got the where="type='access'" trick from mapping multiple sets in one table in hibernate , but the problem is that with the map, the foreign key (A,B,C,X) isn't lining up with the parent table (A,B,C).

Does anyone have any idea how to get this happy? The PARENT_TABLE would be completely redundant if I have to map the map separately.

Answer 1

它不是很漂亮，并且也使Schemaexport变得无用，但是要使其正常工作，您需要指定条件条件以使父级唯一，将insert / update设置为false并让映射间接保留父级。

<class name="parent" table="PARENT_TABLE" where="x = (SELECT x FROM PARENT_TABLE p WHERE p.(a,b,c) = a,b,c LIMIT 1)" insert="false" update="false">