yes, we already thought of that work around.
there's a couple of downsides with that approach for my situation. We have a modeling tool which generates the C# classes with the appropriate NHibernate attributes. In the tool we support the concept of table per class and discriminator. To use the where clause approach, we would need to add logic to handle that "special case". Adding special logic for that case feels like a hack to me, since we expect other users to add subclasses in the future. I was hoping the patch for it is simple, since NH 1.2.1 clearly adds the discriminator column to the select clause when I add a dummy subclass. peter On Sep 26, 2:48 pm, "Jon Palmer" <[EMAIL PROTECTED]> wrote: > You don't need to get into filters to support the legacy data base with data > you don't want use the where clause in the mapping. So instead of this: > > <class name="Address" table="Addresses" discriminator-value="myAddress" > > > <id name="ID" column="ID" type="integer" > > > <generator class="identity"/> > > </id> > > <discriminator column="AddressType" type="string"/> > > ........ > > </class> > > You do this: > > <class name="Address" table="Addresses" where="AddressType = 'myAddress'" > > > <id name="ID" column="ID" type="integer"> > > <generator class="identity"/> > > </id> > > ........ > > </class> > > Jon > > From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Tuna > Toksöz > Sent: Friday, September 26, 2008 11:43 AM > To: [email protected] > Subject: [nhusers] Re: Discriminator bug > > http://www.hibernate.org/hib_docs/nhibernate/1.2/reference/en/html/fi... > > On Fri, Sep 26, 2008 at 9:40 PM, Tuna Toksöz <[EMAIL PROTECTED]> wrote: > > I think this is where filters come into play? > > On Fri, Sep 26, 2008 at 9:31 PM, Jon Palmer <[EMAIL PROTECTED]> wrote: > > Can't you just specify a Where clause in the definition of the single > class mapping. > > -----Original Message----- > From: [email protected] [mailto:[EMAIL PROTECTED] On > > Behalf Of Peter Lin > Sent: Friday, September 26, 2008 11:29 AM > To: nhusers > Subject: [nhusers] Re: Discriminator bug > > the reason is simple. what if I'm reading data from an existing > database, which uses the concept of a discriminator with > address_type_code. what if the address table has entries with > different address_type_code values? > > If I only want to get a specific type of address from the database and > I don't have a subclass, NHibernate wouldn't return the correct > result. It would return all rows, instead of just the rows with the > specific address_type_code. > > I just looked at the release notes for NH 2.0 and it looks like this > scenario is supported. > > Added [ Table per subclass, using a discriminator ] Support to > Nhibernate > > http://ayende.com/Blog/archive/2008/03/31/NHibernate-2.0-Alpha-is-out.as > px > > unfortunately, I can't upgrade to NH 2.0. I understand NH might not > consider this a valid use case, but I definitely consider it a valid > use case. > > peter > > On Sep 26, 11:20 am, "Fabio Maulo" <[EMAIL PROTECTED]> wrote: > > Why you think that it is a bug ?If a class don't have a <subclass> > (mean you > > have only one value for discriminator and that mean don't have nothing > to > > discriminate), why NH must add the discriminator clause ? > > > 2008/9/26 Peter Lin <[EMAIL PROTECTED]> > > -- > Tuna Toksöz > > Typos included to enhance the readers attention! > > -- > Tuna Toksöz > > Typos included to enhance the readers attention! --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
