Alex, I can't remember the whole codebase.
just take care, pass all tests and, please, change that behavior in a
alpha because, in general, the real problem is visible in a complex
scenario.

--
Fabio Maulo


El 07/08/2012, a las 03:22, "Alexander I. Zaytsev"
<[email protected]> escribió:

> The only difference I've found when a child entity is saving outside
> of an association (has no magazine in your example) NH explicitly
> inserts NULL to a FK (could be eliminated by
> dynamic-update/dynamic-insert)
>
>    INSERT
>    INTO
>        Child
>        (Name, ParentId, Id)
>    VALUES
>        (@p0, @p1, @p2);
>    @p0 = 'Bob's Child' [Type: String (4000)], @p1 = NULL [Type: Guid
> (0)], @p2 = 3a55de1d-fa69-4014-9c22-a0a600c876e8 [Type: Guid (0)]
>
> All other things do work as before.
>
>
> 2012/8/7 Fabio Maulo <[email protected]>:
>> It may work but the concept is not the same.
>> The not-nullable FK mean that NH have to track the unidirectional
>> one-to-many (in the domain model) because it have to work as a
>> mandatory bidirectional one-to-many<->many-to-one in the DB.
>> With a nullable FK the relation is just an option and NH does not have
>> to track the backref to the parent.
>> a case:
>> we have a video as standalone entity or a video associated to a
>> magazine. in this case the magazine may have a video associted in a
>> collection. the association de-association is performed with an UPDATE
>> because you can INSERT the video before INSERT the magazine and then
>> you can perform the association beteween the two entities.
>>
>> if we have a reletion as "the video can exists just when associated in
>> a magazine"  the unidirectional association represents a real
>> parent-child (the child can't exists without the parent) and the
>> association/de-association is performed via INSERT-REMOVE, as in a
>> bidirectional relation, but with a unidirectional relation in the
>> domain model.
>>
>> btw the matter is always the same: you can change the behavior passing
>> all tests and then wait for bugs ;)
>> just take care to do it inside an alpha release (in this case)
>> --
>> Fabio Maulo
>>
>>
>> El 06/08/2012, a las 18:00, "Alexander I. Zaytsev"
>> <[email protected]> escribió:
>>
>>> Thanks, but I understand what this is and how it works. I do not
>>> understand why this is applied only to not-null FK, as it works with
>>> nullable FK too.
>>>
>>> If we will remove this check we will get consistent behavior for null
>>> FK and for not-null FK
>>>
>>> 2012/8/7 Fabio Maulo <[email protected]>:
>>>> The unidirectional one-to-many is a base feature of NH since 1.2 or
>>>> before...
>>>>
>>>> What you are watching is a special case, exactly to manage and optimize the
>>>> case when the FK is not-nullable.
>>>> Instead INSERT+UPDATE, as managed for no-mandatory unidirectional
>>>> one-to-many (where the "item" side may have its own lifecycle), the case 
>>>> for
>>>> mandatory unidirectional one-to-many (FK not-nullable) works with INSERT
>>>> directly using a "fake" property for the backref to the parent.
>>>>
>>>> On Mon, Aug 6, 2012 at 11:10 AM, Alexander I. Zaytsev
>>>> <[email protected]> wrote:
>>>>>
>>>>> Hi, all
>>>>>
>>>>> As you may know NH since 3.2 supports uni-directional one-to-many
>>>>> associations.
>>>>>
>>>>> This was done by these commits
>>>>>
>>>>>
>>>>> https://github.com/nhibernate/nhibernate-core/commit/cb60f2169e7504ff83e601c555e42171f28ef9ff
>>>>>
>>>>>
>>>>> https://github.com/nhibernate/nhibernate-core/commit/d6cc06bbfee56fc3ae224fdfdc862df4fdff0442
>>>>>
>>>>> I wonder why this fix is applied only to keys with not-null="true"
>>>>> attribute? I've checked and it seems that all works perfectly without
>>>>> checking that key is not nullable.
>>>>>
>>>>> As I understand the fix was ported from Hibernate, because there I've
>>>>> found exactly the same code.
>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Fabio Maulo
>>>>

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