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Billy,

Just a quick question -- why is the BeginTransaction code in the NHibernateSessionModule commented out?  Does the transaction get initialized somewhere else that I'm not seeing?

Thanks

Connor

Billy,

While I've looked at NHibernate several times in the past, I've selected to use other frameworks for one reason or another.  I very much like the POCO based design, which keep bringing me back to NH.  I enjoyed reading your article and I'm looking through the code.  Something that stands out:  While watching ListCustomers.aspx run with SQL Profiler running, NHibernate seems to be make many, many queries.  It appears a SELECT is issued for each individual Customer row (nearly 100), when they could all be easily fetched with a single query.  Is this normal NHibernate behavior?

I discovered the same behavior except for objects that don't have relations (bags and many-to-one).

Thanks Billy.

The problem resides in the property getter of the collection (get { return new List<Order>(orders).AsReadOnly(); }).

Billy, I have downloaded the basic sample and there is a question for u.

Uptill nowm wat i have done in my projects is that i add reference to dataaccesslayer , from BusinessLayer.

But here , u have added the ref. of businessObj to dataaccesslayer. The Data project contains only the implementation of the interfaces + some session management code for NH.

Wat i think is that DAO interfaces and their implementation shud be kept together in seperate assemblies.That assembly shud be referenced by DomainObj.

Does that make any sense?

Hi Billy - I have a question regarding the use of MVP/NHibernate in combination with some of the standard databound control provided by the ASP.NET 2.0 framework.

If I want to create a small user control that takes care of editing an entity I would normally opt for a FormView control. However, using a FormView control within a "View" in the MVP sense I would have to become very familiar with the events of the FormView in order to delegate work to the Presenter, which seems to be a lot of work.

I seems to me that to go true MVP I would have to abandon FormView and simply create a set of Panels with controls that I enable as needed depending on whether I am viewing, editing or inserting.

What is your opinion on that?

When you work with MVP, do you use the built-in databound controls or do you create your own "simpler" views?

Thanks in advance.  :-)

Thomas

Thanks Billy for the great article.  I've been looking at NH for some time and your article convinced me that this is a great ORM.

I have one inquiry though on how NH can be used in a more generic way.  I would ideally like to build a DAL component that can be used by multiple projects.  

Your article talks about IoC pattern by which the DAL references the Biz layer, using interfaces to the biz objects.  This is perfect for a single project, but I don't see how this would work for a DAL component that is used by N projects.

what are your thoughts about this?

Hi Billy,

I am still in confuse about transaction management.

As you know, when working with NHibernate, we begin with sess.BeginTrans and finish with sess.Commit or sess.Rollback.

In your article, you use a HttpModule to add process on BeginRequest and EndRequest to do the transaction management. But what will happpen when the transaction fail? I cannot see the code when you call Rollback transaction.

Please will me more explanation about this.

Hi Bill

On your article about NHibernate best practices you mentioned a idea to create a guidance package to perhaps help with the creation of the DAL and objects.

To the best of your knowledge has anyone tackled this challenge?

I am thinking of giving it a go, not knowing much about creating GP it should be an interesting exercise.

Regards

Rhys

ADO.NET Entity Framework with Oracle

Hello,

 I'm an NH beginner , your article is so great ! I learned more besides NH.  

I find there is no code to demonstrate how to delete an instance ,can you add some ?

I know when I call Isession.delete(obj), the instance become detatched, will it be removed from the underlying datasource?

sorry I mean the datasource control like objectdataSource

wow!  Time in my place is 2:16 am , I must go to sleep now!!

I'm seeing a problem along the same lines as what Giacomo described back in May. I have a many-to-many bag, and NHibernate deletes its contents when I Flush the session. It definitely has to do with the collection getter. If I change it from return new List<Order>(orders).AsReadOnly() to simply return orders, it works fine.

Hi Billy,

I've been reading your EnterpriceSample and I find very useful.

I have a question converning the Castle framework. I notice that you set a path in the CastleComponents.config file for the NorthwindNHibernate.config. So I was wondering what happened if I want to deploy my project on Hosting Provider. I mean I won't have any idea where the config file will be placed so I would have to use a relative path.

How would you do that? I will appreciate any suggestion

Thanks a lot

Hi Billy, first thanks for those great article. I have a confusion regarding collections. Having the following:

public IList<OrderLine> OrderLines {

           get { return new List<OrderLine>(_orderLine).AsReadOnly(); }

       }

I expected that the collection OrderLines was ReadOnly but still i can modify OrderLine properties from grids. How can i make sure that  OrderLine is true ReadOnly?

Thanks

I get it, that confuse me, beacuse as one read "AsReadOnly" my firts instinct was "i will get a totally readonly collection for free".

Thanks Billy, keep good work