10-4 Episode 15: Model-First Development with the Entity Framework 4.0

The Discussion

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  okay, when can we get our hands on this?  The wait has been waaaaay too long for my AADHD to tollerate.  Feed me seymore!  Feed me now!

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  That is great!  It's nice to see the EF become even more mature.  It would be even better if we had more control over the physical dml is generated, or if we had a choice to output complex-types to separate tables and have them linked via a foreign key to their parent.  If the customer you created had more than one physical address, say a billing and/or shipping, you'd need to modify your database to support this or you could create a second Address complex-type, but this could get very messy, not to mention confusing.
  
  Also, I attempted to use EF that shipped with 3.5 on a database at work and I subsequently went back to LINQ because the EF wizard "forgot" to pull two of my tables from my database.  I attempted to regenerate the model several times with no luck.   These tables were found in the generated files, but were not present to the tool, nor did visual studio recongize them.  I also recieved compiler errors when I attempted to reference them.  I am wondering if anyone else had this problem with bridging tables which facilitate many-to-many relationships.
  

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  Note that the database connection wizard was the one who created the database, not specifically the generate database wizard from the entity framework. It's likely the wizard will always just generate a script to make you do this yourself..
  
  Also, isn't this entity framework v2? is there anything there regarding POCO models? I know they were suposed to be adding this, I'd much rather create ignorant models with INotifyPropertyChanged and generate a conceptual from them, and generate a database schema from the conceptual model.

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  POCO models are added in, check out Pablo Castro's mix video where he says this is forthcoming
  

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  Very interesting! When can we play with a new ctp? The actual one is too OLD

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  No kidding eh?  I know that is why I'm not rushing out to download it, I'd like to try it with the new interface, warts and all.
  

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  so are you going to be releasing another CTP or a beta anytime soon?  Its about to be May and all there is out there is as far as news is the same tired old links from October.  I'd love to read some buzz about it at least.  BTW  why isnt the .NET framework ever released before the IDE?  after all they are two totally seperate entities right?  I sont mind command line compilation and notepad coding if thats what ita takes to get my hands on this technology.

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  As long I you fix simple things like being able to do model.DeleteCustomers (c => c.Surname == "Smith") i'll be happy.

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  Features that need to be there:
  -Change scripts as well as create scripts (looks like this is already there?)
  -Sized fields like Varchar need to have some way to map back field. In fact if you could constrain the field as an EF field during any save operation that would be better. I am talking zero custom code. I set String field with Length 20 in the tooling. It throws an exception on 21+ characters.

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  Hi folks,
  
  Thought I'd mention an ORM product I've been using - Mindscape LightSpeed - which has provided model first and database first support for quite some time. It has a model designer that integrates directly into VS, supports schema round tripping in both directions and heaps more. It doesn't support such a rich conceptual modelling capability as EF but I find it fits what I need. Also supports 9 database types.
  
  Just thought i'd make some LightSpeed-specific comparisons with posts here -
  
  @PerfectPhase You can write a query similar to that using LightSpeed. UnitOfWork.Remove() takes a query object that can be as complex as you wish and will delete all records that match without returning data to the client.
  
  @foreachdev You can configure the LightSpeed validation in the designer to not allow persistence if a field is over a given length. If an entity has a field that had 21 characters the .IsValid flag would be false and the errors collection would supply a description of the issue to present to the user if desired. Change scripts are supported in a rough manner but this is getting much tidier in the next version I hear.
  
  While we wait for EF 2 to pop out you could have a look at LightSpeed Express here.
  
  

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  .NET Framework 3.0 was released before the VS23008 IDE. Some extensions were added to VS2005 for WCF and WF but you could always use notepad

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  It's nice to see that this concept will be improved. But i think you should have a deep look at the extended data types of Microsoft Dynamics AX. That's a great thing i currently miss in Visual Studio.

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  can we see how to use the API-level aspects of this framework? preferrably in a test-driven fashion? this is what I really need to see to compare this against the Rails style of development. pointing and clicking all over the UI doesn't really do it for me, I'm a keyboard-oriented person.

  I really love the 10-4 videos, especially the ones that JC does. Keep up the good work!

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  LINQ To SQL is getting quit a few improvements in the .NET 4 timeframe. You can see a pretty comprehensive list here: http://damieng.com/blog/2009/06/01/linq-to-sql-changes-in-net-40

  As far as the Entity Framework being the preferred option for data access moving forward, yes, that is the case.

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  Thanks for the heads up bertnz. The ORM space certainly has lots of great options.

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  I'll definitely be digging into the code much more moving forward. This episode was just an initial introduction to the high level changes coming. I'll make sure to provide plenty of good detail/usage examples

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  Sounds like what you want it to use Dynamics as your data store/platform, and then place the Entity Framework over it so that you can program against its dynamic entities. If so, the guys over at ADX Studio (http://www.adxstudio.com/) are working on something that handles this very nicely.

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  Hi! What happens if i want to add enumeration to my model? How's that gonna be represented in Database?