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 --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
