I can't send a actual classes and tables, but try to consider simple
example:
abstract class BusinessObject
{
}
class ConcreteObject1 : BusinessObject
{
}
class ConcreteObject2 : BusinessObject
{
}
On 20 Lut, 16:26, Fabio Maulo <[email protected]> wrote:
> Ok.Please send classes and tables, then we can talk about mappings.
>
> 2009/2/20 Piotr Jakóbczyk <[email protected]>
>
>
>
>
>
> > Yes, I know syntax of "mixing table per class hierarchy with table per
> > subclass".
> > But I require one SHALLOW (used as read-onlu) hierarchy used <union-
> > subclass> and several distinct hierarchy used "mixing table per class
> > hierarchy with table per subclass" with base db tables from first one
> > hierarchy.
>
> > On 20 Lut, 15:57, Fabio Maulo <[email protected]> wrote:
> > > The strategy "mixing table per class hierarchy with table per subclass"
> > is a
> > > special and specific feature of Hibernate and NHibernate.The
> > implementation
> > > is
> > > <class>
> > > <discriminator ..../>
> > > <subclass>
> > > <join>
> > > </join>
> > > </subclass>
> > > <subclass>
> > > <join>
> > > </join>
> > > </subclass>
> > > </class>
>
> > > Reference here:
> >http://nhforge.org/doc/nh/en/index.html#inheritance-tablepersubclass-...
>
> > > 2009/2/20 Piotr Jakóbczyk <[email protected]>
>
> > > > Thanks for quick response.
> > > > Let my explain in details what kind of mappings I need.
>
> > > > We have composed hierarchy of objects with common base abstract class
> > > > - BusinessObject. Until now we have whole hierarchy mapped by <joined-
> > > > subclass>. But becouse of performance reasons and specificity of
> > > > realized queries we want to horizontally divide base table of our
> > > > hierarchy into a few distinct tables: TABLE1, TABLE2, TABLE3.
>
> > > > The idea is following:
> > > > For every new distinct tables should be prepared new classes:
> > > > Class1Marker, Class2Marker, Class3Marker derivated from BusinessObject
> > > > class.
> > > > Class1Marker, Class2Marker and Class3Marker classes are mapped by
> > > > <union-subcless>.
>
> > > > In this way, we will have SHALLOW hierarchy of object derivated from
> > > > BusinessObject class (stored in several tables: TABLE1, TABLE2,
> > > > TABLE3).
> > > > This hierarchy is sufficient for most of required and frequently
> > > > executed queries and will be used for read only.
>
> > > > But any of Class1Marker, Class2Marker, Class3Marker classes does not
> > > > represent concrete object.
> > > > So we want to prepare additional distinct hierarhies beased of a
> > > > tables TABLE1, TABLE2, TABLE3. For each table separated hierarchy may
> > > > used different inheritance strategy (mixing table per class hierarchy
> > > > with table per subclass). To do this we need to prepare another
> > > > mappings for tables TABLE1, TABLE2, TABLE3 and classes Class1, Class2,
> > > > Class3 (not marker).
>
> > > > Everything works fine untill mappings of BusinessObject and
> > > > Class1Marker, Class2Marker, Class3Marker classes are placed before
> > > > other mapping for tables TABLE1, TABLE2, TABLE3.
>
> > > > On 20 Lut, 14:55, Fabio Maulo <[email protected]> wrote:
> > > > > You CAN'T use <union-subclass> mapping more than one class to the
> > same
> > > > > table.
> > > > > If you want use only one table you must use <subclass> or a trick
> > like
> > > > thishttp://fabiomaulo.blogspot.com/2008/10/power-of-orm.html
>
> > > > > 2009/2/20 Piotr Jakóbczyk <[email protected]>
>
> > > > > > I know what union-subclass is and I read references about all
> > > > > > inheritance strategy implemented by NH.
> > > > > > In my example I used <union-subclass> (look at SubclassA entity
> > > > > > mapping).
> > > > > > But why, in my example, the changing of the order of mapping
> > > > > > definitions provide different behevoiur of NH. The first order
> > raises
> > > > > > exception, but the second not.
>
> > > > > > On 20 Lut, 13:45, Fabio Maulo <[email protected]> wrote:
> > > > > > > union-subclass is an advanced way provided by NH to implement the
> > > > mapping
> > > > > > > pattern : table-per-concrete-class
> > > > > > > What you are looking for is the implementation of the pattern :
> > > > > > > table-per-class-hierarchy
> > > > > > > The tag for that is <subclass>; reference available herehttp://
> > > > > > nhforge.org/doc/nh/en/index.html#mapping-declaration-subclass
>
> > > > > > > --
> > > > > > > Fabio Maulo
>
> > > > > > --
> > > > > > Piotr Jakóbczyk
>
> > > > > --
> > > > > Fabio Maulo
>
> > > > --
> > > > Piotr Jakóbczyk
>
> > > --
> > > Fabio Maulo
>
> > --
> > Piotr Jakóbczyk
>
> --
> Fabio Maulo
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"nhusers" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/nhusers?hl=en
-~----------~----~----~----~------~----~------~--~---
