Dear nH users,
I'm a beginner of nHibernate and I have a question about releation.
I have a main object called Contenzioso and it has some details with a number and a dateTime.

It works great, but if I use this code, the DateNumberDetails previus store into database will not delete automatically...

[...]
Contenzioso c = ..."session.get(id)";...
c.eventA = null;

Probably I miss something in the DateNumberDetails mapping file...
The strange things is that if I assign a new DateNumberDetails with new values, nHibernate replace the values of the old row into the db.


the POCO classes are like

class Contenzioso
{
public long id {get;}
public string description {get;set;}
public DateNumberDetails eventA {get;set;}
public DateNumberDetails eventB {get;set;}
}


class DateNumberDetails
{
public long id {get;}
public DateTime date {get;set;}
public string number {get;set;}
}




Hibernate version: 2.0.1

Mapping documents:
is something like this...

<class name="Contenzioso" table="dbo.Contenziosi" lazy="true">

<id name="id" unsaved-value="0" access="field" type="System.Int64">
<column name="id"/>
<generator class="native" />
</id>

<property name="description" column="description" type="System.String" />

<many-to-one name="eventA "
class="DateNumberDetails"
column="eventAId"
cascade="all-delete-orphan"
/>


<many-to-one name="eventB "
class="DateNumberDetails"
column="eventAId"
cascade="all-delete-orphan"
/>
[...]
</class>

<class name="DateNumberDetails" table="dbo.DateNumberDetails" lazy="true">

<id name="id" unsaved-value="0" access="field" type="System.Int64">
<column name="id"/>
<generator class="native" />
</id>

<property name="Data" column="Data" type="System.DateTime" />
<property name="Numero" column="Numero" type="System.String" />

</class>

Cascade only works if you explicitly delete c. Setting eventA to null is something different. And when you speak about setting new values, did the new detail had an id = 0 ?

Your "detail" sounds more like a one-to-one association anyway. Is there a reason for a many-to-one ?

I will check the id value.

I read the reference and some manual and seems that the one-to-one is achieved using the same id for both of the row in the two tables... Each property is one-to-one, but the Contenzioso row has more details...
Probably the right solution is one-to-one... but how I can do that using explicit id into Contenzioso table?

If one row can have more details than you need a one-to-many. Which then will be a list of details on the Contenzioso class.

Not exactly a list of details, becuase every detail has a different semantic and is not only a set.
For example a detail is the initial information (date and number of protocol), another is the validation information and so on...
Not all the details are available for all contenzioso.

You can try unique="true" on the many-to-one. Maybe that will get you the expected deletes. If you move to a one-to-one you can use property-ref to use properties different than the id on the target end.