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From Andy Jefferson <a...@jpox.org>
Subject Re: Embedded collections of non-PC objects
Date Fri, 15 Jul 2005 09:41:49 GMT
Some corrections to the previous attempt (due to excessive use of the 
Ctrl-C-Ctrl-V design pattern) :-

> Example 1 : Collection of BigDecimal

I accidentally omitted this option
3. Embedded collection
<field name="myfield" embedded="true">
    <collection element-type="java.math.BigInteger"/>
</field>
No idea what is expected here .. probably the same as "serialised" option ? 
Not currently implemented by JPOX.


> Example 2 : Collection of PC

> 2. Basic collection with FK
> <field name="myfield">
>     <collection element-type="MyElement"/>
> </field>
This creates *2* tables - 1 for the class owning "myfield", 1 for the element 
class (with FK back to the owner table).

> 3. Embedded element
> <field name="myfield">
>     <collection element-type="MyElement" embedded-element="true"/>
>     <join/>
> </field>

This creates *2* tables - 1 for the class owning "myfield", and 1 join table
containing the elements (columns aligned with the fields of the PC element).

> 4. Embedded element (fully specified)
> <field name="myfield">
>     <collection element-type="MyElement" embedded-element="true"/>
>     <join/>
>     <element>
>         <embedded>
>             ... (full spec of field mappings)
>         </embedded>
>     </element>
> </field>

This creates *2* tables - 1 for the class owning "myfield", and 1 join table 
containing the (embedded) elements (columns aligned with the mappings 
specified in the <embedded> section above.



-- 
Andy

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