Thanks for the pointer to the mapping flags.. I see how dynamic-update
does what I need it to.

I'm not sure how much work we're talking about to use the
interceptor.  I guess what I need to do is, when a new entity is
created, I need to prevent it from creating anything other than the
parent table, and i'm not sure how difficult that would be to
accomplish in the interceptor.

On Dec 5, 4:59 pm, cws <[email protected]> wrote:
> Hello!
>
> You colud configure NH to only update-insert necessary columns that
> have been changed.
> Seehttp://nhforge.org/doc/nh/en/index.html#mapping-declaration-class
>
> In detached scenario when you have a entity not attached to session it
> is possible to use select-before-update
> see link above as well.
>
> For the second one
> seehttp://nhforge.org/doc/nh/en/index.html#mapping-generated
> or you could use the Refresh method of ISession.
>
> I think you could use the generated attribute for the last as well,
> but I am not sure.
> There is another option to use a Interceptor to alter the generated
> insert statement in runtime.
> seehttp://nhforge.org/doc/nh/en/index.html#manipulatingdata-interceptors
>
> On Dec 5, 8:20 pm, Erik Wilson <[email protected]> wrote:
>
>
>
> > Hello, I am considering using nhibernate in my project, but I have
> > some questions about the way it works that I was hoping someone could
> > answer.
>
> > First, when an update operation is performed, does it update all
> > fields in the entity, or only the changed fields?  I ask, because the
> > database I have to use (and I don't control it's format, nor can I
> > change it in any way) has a number of triggers that operate on the
> > updated data (such as logging).  So an UPDATE foo SET bar=1, zoo=2
> > would log both bar and zoo, even if the value of 2 hadn't actually
> > changed.  Linq2Sql only updates the fields that have chaned, and I was
> > curious if nh did the same.
>
> > Second, and again this is an issue because of triggers in the
> > database, I have a table that when a new record is inserted, the
> > trigger automatically inserts records in other (child) tables and
> > makes the table a foreign key.  This ensures that all tables have
> > default records if a parent record exists.  Consider this as something
> > akin to inheritence where there's a common set of data, and depending
> > on a discriminator other tables are used in a given entity.  For
> > example, if you had a person table, and an employee table that used
> > person as a foriegn key.
>
> > I understand how to make the employee table use the two tables via a
> > discriminator.  My concern that when a new employee is created, only a
> > person is created, and a default employee record gets created
> > automatically by the trigger if it's personType field is "employee".
>
> > How exactly would nh deal with this situation?  I would be creating an
> > entity which joins the parent and child tables into a single entity,
> > but when I create a new entity it would need to only create the sql to
> > create the parent (since the children get created automatically).
> > does nh have support for this, or would I have to issue my create sql
> > seperately?- Hide quoted text -
>
> - Show quoted text -

--

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.


Reply via email to