That is not how it works. The binding of sub classes is done on the config
level, not in the SF.

On Fri, Sep 26, 2008 at 11:55 PM, Tuna Toksöz <[EMAIL PROTECTED]> wrote:

> What if the parent is in another assembly(so is its mapping), one may not
> have chance to change the parent mapping.
>
> On Fri, Sep 26, 2008 at 11:52 PM, Ayende Rahien <[EMAIL PROTECTED]> wrote:
>
>> Yes, but what about it? Assuming that you have the correct mapping, the
>> appropriate behavior will happen
>>
>> On Fri, Sep 26, 2008 at 11:50 PM, Tuna Toksöz <[EMAIL PROTECTED]> wrote:
>>
>>> I see Peter's point, an assembly which may be closed and another assembly
>>> which may add subclasses, isn't this a possible thing?
>>>
>>>
>>> On Fri, Sep 26, 2008 at 11:44 PM, Jon Palmer <
>>> [EMAIL PROTECTED]> wrote:
>>>
>>>>
>>>> There are two things going on in your scenario
>>>>
>>>> 1. Returning the correct type of mapped object
>>>> 2. Filtering the rows due to legacy data.
>>>>
>>>>
>>>> Returning the correct type of mapped object
>>>> In The case that there is only one class NHibernate assumes every row in
>>>> the table is of that class. It has no need to add the address_type_code
>>>> to the select because it's going to build Addresses regardless of the
>>>> value. It would be very strange (and I suspect broken) to expect
>>>> Nhibernate to query for the rows and then only hydrate into Addresses
>>>> those entries that matched the discriminator. In that situation the row
>>>> Count of the sql query would could be different than the count of actual
>>>> objects returned after hydration. Yuck.
>>>>
>>>> As soon as you add a subclass NHibernate will add the address_type_code
>>>> column so that it can chose which class to create. I suspect that its
>>>> entirely right it only does this when it needs to.
>>>>
>>>>
>>>> Filtering the rows due to legacy data
>>>> To remove you data that doesn't match address_type_code = home_address
>>>> you should expect something to appear in the where clause. The
>>>> alternative, that you query for everything and then cut down the results
>>>> set during hydration rather than in the sql query, is likely to be ugly
>>>> and perform extremely badly depending on the distribution of non
>>>> home_address address rows.
>>>>
>>>> As I described in an earlier email, it's entirely right, indeed
>>>> preferable, that NHibernate does not add the where clause when you query
>>>> for the base class (as is always the case if there is only one class).
>>>>
>>>> Jon
>>>>
>>>> -----Original Message-----
>>>> From: [email protected] [mailto:[EMAIL PROTECTED] On
>>>> Behalf Of Peter Lin
>>>> Sent: Friday, September 26, 2008 12:37 PM
>>>> To: nhusers
>>>> Subject: [nhusers] Re: Discriminator bug
>>>>
>>>>
>>>>
>>>> sorry for the confusing explanations. I'll attempt to explain it
>>>> better.
>>>>
>>>> Here is the situation.
>>>>
>>>> I. I have a table in a legacy database which has existing records
>>>> which use the concept of a discriminator. In other words, there is a
>>>> type_code column, which has different values.
>>>>
>>>>
>>>> II. I have a C# object which represents an entity. The entity maps to
>>>> records in the table with a specific discriminator value.
>>>>
>>>>
>>>> III. I only want to get the records with a specific discriminator
>>>> value from the table like "home_address".
>>>>
>>>>
>>>> IV. I have a modeling tool which generates C# classes with the
>>>> appropriate NH attributes. Changing the code gen for the special case
>>>> to use one of the work arounds feels like a hack to me.
>>>>
>>>> V. since polymorphic queries require the discriminator column to
>>>> create the correct object instance, shouldn't it always include it in
>>>> the select part of the sql statement?
>>>>
>>>> thanks for taking time to listen and respond.
>>>>
>>>> peter
>>>>
>>>> On Sep 26, 3:20 pm, "Jon Palmer" <[EMAIL PROTECTED]> wrote:
>>>> > If you have only one class mapped then the only thing it can return is
>>>> > that one class so why would it need the address_type_code column?
>>>> >
>>>> > One of your previous emails indicated the problem was returning all
>>>> rows
>>>> > from the table. I'm confused about what the problem is your tryign to
>>>> > solve.
>>>> >
>>>> > Jon
>>>> >
>>>>
>>>>
>>>>
>>>>
>>>>
>>>
>>>
>>> --
>>> Tuna Toksöz
>>>
>>> Typos included to enhance the readers attention!
>>>
>>>
>>>
>>
>>
>>
>
>
> --
> Tuna Toksöz
>
> Typos included to enhance the readers attention!
>
> >
>

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