Load Id which don't exist

Papy214 · **Joined:** Fri Feb 29, 2008 9:36 am **Posts:** 40

Hi,

When I code:

settings = session.Load(typeof(Settings), 1) as Settings;

If there's no Id with value 1, none error is thrown !

Is it a way to detect that there's a problem in load object ?

Thanks !

Papy (France)

wolli · **Posted:** Fri May 16, 2008 9:40 am

Quote:

Note that Load() will throw an unrecoverable exception if there is no matching database row. If the class is
mapped with a proxy, Load() returns an object that is an uninitialized proxy and does not actually hit the database
until you invoke a method of the object.

According to the docs, you should get an exception. Do you use lazy loading ?

Papy214 · **Joined:** Fri Feb 29, 2008 9:36 am **Posts:** 40

The real case is on user object which is linked to a profile table.

I use lazy=false in my hbm.xml

Code:

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" 
                   default-lazy="false"
                   namespace="Cube_database.model"
                   assembly="Cube database">

there's also:

   <many-to-one name="_profile"  access="field.pascalcase-underscore" not-null="false" outer-join="auto" lazy="false" insert="true" update="true">
      <column name="id_profile"/>
    </many-to-one>

the profile loading throw a lazyinitialisationexception but the code to load user don't throw exception.

Code:

        internal static UsersEntity User(int Id, bool n, NHibernate.ISession session)
        {
            UsersEntity user = null;
            try
            {
                try
                {
                    user = session.Load(typeof(model.UsersEntity), Id) as model.UsersEntity;
                }
                catch (System.Exception)
                {
                    throw;
                }
            }
            finally
            {
                session.Close();
            }
            return user;
        }

The code jump from
user = session.Load
to
session.Close();

wolli · **Posted:** Fri May 16, 2008 12:18 pm

What do you mean with

Quote:

the profile loading throw a lazyinitialisationexception but the code to load user don't throw exception.

Quote:

The code jump from
user = session.Load
to
session.Close();

Isn't that the correct bahaviour for "finally" ? session.Close() should be executed before the exception is rethrown.

Papy214 · **Joined:** Fri Feb 29, 2008 9:36 am **Posts:** 40

Quote:

the profile loading throw a lazyinitialisationexception but the code to load user don't throw exception.

I have added a line of code in catch

Code:

        catch (System.Exception)
        {
            user = null;
            throw;
        }

When I load the user, the code go in finally section and when I quit the function, my user is not null, so the line code "user = null" isn't executed.

But, if I try to use the user object after the function call, I get an ObjectNotFoundException.

I see that the user has several null values in properties (apart default values).
If I "spy" the profile property of the user, C# show me a lazyinitializationException.

To resolve the problem, I have added another line code:

model.ProfilesEntity profil = user._profile;

Code:

UsersEntity user = null;
try
{
    try
    { 
        user = session.Load(typeof(model.UsersEntity), Id) as model.UsersEntity;
        model.ProfilesEntity profil = user._profile;
    }
    catch (NHibernate.ObjectNotFoundException)
    { user = null; }
    catch (System.Exception)
    { user = null; }
}
finally
{
    session.Close();
}
return user;

The of profile property throw the exception and my object is null after call the function.

wolli · **Posted:** Mon May 19, 2008 5:06 am

That souns like your user object gets lazily loaded despite of default-lazy="false". Have you tried to set lazy="false" on the class ?

Btw. I found this comment in the source code:

Quote:

Thrown when ISession.Load() fails to select a row with the given primary key (identifier value). This exception might not be thrown when Load() is called, even if there was no row on the database, because Load() returns a proxy if possible. Applications should use ISession.Get() to test if a row exists in the database.

Papy214 · **Joined:** Fri Feb 29, 2008 9:36 am **Posts:** 40

Quote:

That souns like your user object gets lazily loaded despite of default-lazy="false". Have you tried to set lazy="false" on the class ?

Yes ! with lazy=false, it work properly. The ObjectNotFoundException is thrown.

Thanks a lot ![/code]