Hi !

I am long time user of hibernate, and now I tried to "sell" NHibernate to my current boss, because we starting on new project. Problem is that I can't get it to work...

Problem is with ID generator(s). I have tried several, I read all posts on internet I could find but nothing helps....

I am testing on two different databases, problem is always the same.

Here is hbm.xml (part)

<class name="ArticleH" table="Articles" lazy="false">
<id name="Id" column="ArticleID" type="Int32">
<generator class="native" />
</id>

<property name="Name" column="ArticleName" type="string" length="50" />
<property name="InsertDate" type="DateTime" />

</class>

---

Code is quite simple:

public object AddHibernate(Object obj)
{

log.Info("addHibernate::" + obj.ToString());

ITransaction tx = null;
try
{
ISession sess = GetNewSession();
tx = sess.BeginTransaction();

object val = sess.Save(obj);
tx.Commit();

return val;
}
catch (Exception ex)
{
if (tx != null)
tx.Rollback();

log.Error("Exception on addHibernate: " + ex, ex);
return -1;
}

}

This is method for adding. Problem comes on Commit... So I tried several generators (native, identity and some others).
At first I thought that it's database problem, so I made also PostgreSQL tables on PgSQL database (I started work with MS SQL 2005)

Error is same on both databases.

5687 [10] ERROR HibernateUtil (null) - Exception on addHibernate: NHibernate.HibernateException: identifier of an instance of Comtron.TicDemo.Datalayer.HObjects.ArticleH was altered from 5 to 5
at NHibernate.Event.Default.DefaultFlushEntityEventListener.CheckId(Object obj, IEntityPersister persister, Object id, EntityMode entityMode) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\DefaultFlushEntityEventListener.cs:line
116
at NHibernate.Event.Default.DefaultFlushEntityEventListener.GetValues(Object
entity, EntityEntry entry, EntityMode entityMode, Boolean mightBeDirty, ISession
Implementor session) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\Def
aultFlushEntityEventListener.cs:line 81
at NHibernate.Event.Default.DefaultFlushEntityEventListener.OnFlushEntity(Flu
shEntityEvent event) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\Def
aultFlushEntityEventListener.cs:line 36
at NHibernate.Event.Default.AbstractFlushingEventListener.FlushEntities(Flush
Event event) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\AbstractFlu
shingEventListener.cs:line 161
at NHibernate.Event.Default.AbstractFlushingEventListener.FlushEverythingToEx
ecutions(FlushEvent event) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Defau
lt\AbstractFlushingEventListener.cs:line 60
at NHibernate.Event.Default.DefaultFlushEventListener.OnFlush(FlushEvent even
t) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\DefaultFlushEventList
ener.cs:line 18
at NHibernate.Impl.SessionImpl.Flush() in c:\CSharp\NH\nhibernate\src\NHibern
ate\Impl\SessionImpl.cs:line 1477
at NHibernate.Transaction.AdoTransaction.Commit() in c:\CSharp\NH\nhibernate\
src\NHibernate\Transaction\AdoTransaction.cs:line 187
at HibernateUtil.AddHibernate(Object obj) in D:\workNet\AtechTools\trunk\dot_
net\AtechToolsNet\Db\NHibernate\HibernateUtil.cs:line 226
NHibernate.HibernateException: identifier of an instance of Comtron.TicDemo.Data
layer.HObjects.ArticleH was altered from 5 to 5
at NHibernate.Event.Default.DefaultFlushEntityEventListener.CheckId(Object ob
j, IEntityPersister persister, Object id, EntityMode entityMode) in c:\CSharp\NH
\nhibernate\src\NHibernate\Event\Default\DefaultFlushEntityEventListener.cs:line
116
at NHibernate.Event.Default.DefaultFlushEntityEventListener.GetValues(Object
entity, EntityEntry entry, EntityMode entityMode, Boolean mightBeDirty, ISession
Implementor session) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\Def
aultFlushEntityEventListener.cs:line 81
at NHibernate.Event.Default.DefaultFlushEntityEventListener.OnFlushEntity(Flu
shEntityEvent event) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\Def
aultFlushEntityEventListener.cs:line 36
at NHibernate.Event.Default.AbstractFlushingEventListener.FlushEntities(Flush
Event event) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\AbstractFlu
shingEventListener.cs:line 161
at NHibernate.Event.Default.AbstractFlushingEventListener.FlushEverythingToEx
ecutions(FlushEvent event) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Defau
lt\AbstractFlushingEventListener.cs:line 60
at NHibernate.Event.Default.DefaultFlushEventListener.OnFlush(FlushEvent even
t) in c:\CSharp\NH\nhibernate\src\NHibernate\Event\Default\DefaultFlushEventList
ener.cs:line 18
at NHibernate.Impl.SessionImpl.Flush() in c:\CSharp\NH\nhibernate\src\NHibern
ate\Impl\SessionImpl.cs:line 1477
at NHibernate.Transaction.AdoTransaction.Commit() in c:\CSharp\NH\nhibernate\
src\NHibernate\Transaction\AdoTransaction.cs:line 187
at HibernateUtil.AddHibernate(Object obj) in D:\workNet\AtechTools\trunk\dot_
net\AtechToolsNet\Db\NHibernate\HibernateUtil.cs:line 226


If anyone has any idea what is happening I would be thankful for any help.... And to answer some questions before hand...

I use new Session each time (I tried with using one Session for lifetime of application, as I do with java, but since one article said to create session for each operation I tried that too).

And yes, I get ID from database back, so I think that problem is on nhibernate side.

Andy

Hi !

Me again... I found sollution. It seems that session is per default in autocommit mode, which doesn't work OK with Transactions (double commit). So we can do following:

A.) Don't use transaction:

ISession sess = GetNewSession();
object val = sess.Save(obj);

or

B.) Disable autocommit

ISession sess = GetNewSession();
sess.FlushMode = FlushMode.Never;

tx = sess.BeginTransaction();

object val = sess.Save(obj);
tx.Commit();


I am sorry that I bothered all of you, but I never had this problems in java (not in all of 5 years, since I am using it)

Andy