you dont have to worry about that in EF cause theres only 1 file …. forever .. amazing

It isn’t about which product has more features, is easier to use, or is more efficient than the other. What you want to look at first is your application design and ask yourself this:

“Are we (am I) writing a domain-centric application, or a data-centric application?”

If you cannot tell, then any differences between the products will be pointless. If you can, then read on.

NHibernate is geared toward the domain-centric application, where you must maintain a proper entity ownership pattern. For example:

// To save a new order you must do so via the custom it belongs to
customer.AddOrder(order);
customerRepository.Update(customer);

If you were to expose the customerId in the Order entity and try doing the following, instead:

orderRepository.Insert(order);

It might actually save to the database (depending on your mappings), but due to the way NH caches data, subsequent selects will not reflect the change.

This is where the MS products shine. They are geared towards the data-centric application, making the second code example a reality.

In the end, your decision should not simply be “which ORM is better” but “which ORM is better for OUR needs?”

Rob Conery postsed some good words on the topic: http://blog.wekeroad.com/2009/12/26/thoughts-on-ef-vs-nhibernate-redux

I have been working with nHibernate for a year or so and find it very powerfull. It has a steep learning curve and needs a deep understanding of the inner workings and mappings to really get it to shine. There are some amazing features like futures, result transformers, lucene and more. The learning curve is steep, but manageable. Getting various stacks to play nice can also be challenging for new learners. MS will no doubt cover the docs in detail and will have tons of resources by comparison. Nhibernate has 1 book – its great though.

As an out-of-the-box solution, I feel EF will be easier to work with for most developers and with MS pushing it, will be more appealing for most, especially now with POCO support.

My current framework has been developed to allow either EF or nHibernate to plug in and take over as the orm. Some initial config work, DI and unit of work pattern allow the app to be agnostic as to who is handling mapping and data access. Ritesh Rao has a great project called nCommon which is well worth checking out to appreciated both architectures: http://code.google.com/p/ncommon/

In a nutshell – as a developer you need to know both and the concepts are the same. Once you have a solid understanding, it will come down to personal preference.

PS – Ster Trek sucks

Excellent. Work Flawlessly!!!!

Thanks,

Pablo.

Sorry it’s taken awhile to respond . There’s no need in Visual Studio to use Datasets for data binding. You get the same binding components using an “Object” data source. Just create a data source and select a WCF generated class. Then drag the data source over to a window design surface. This is functionality is available in Visual Studio 2010 for both Windows Forms and WPF apps.

That’s all there is to it. Please let me know if this answers your question.

Cheers,
Tony

I do have a question. When I get in the client and add the proxy. I will like to have a Dataset that I will drag and drop on the form and also put a binding navigation Component.

In my case I have many tables that I need simple navigation and updates and I will like to transform my application using WCF and EF4.

Thanks in Advance, from Dominican Republic.

http://ayende.com/Blog/archive/2010/01/13/designing-the-entity-framework-2nd-level-cache.aspx