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ADO.NET Entity Framework - Orcas Beta 1

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What else do you need to know about the Entity Framework? We've documented basic syntax and provided a few samples. How can we improve the documentation? Send us scenarios you want to implement.

Orcas Beta 1 contains the ADO.NET Entity Framework. This technology requires new ways of thinking about data applications. The documentation included with Beta 1 introduces design concepts and provides examples to get you up and running as quickly as possible. The ADO.NET team blog will help to answer questions that remain after you've read enough of the documentation to implement an Entity Data Model and write some code using the Entity Client.

We want to answer your questions. As you begin to work with the Entity Framework, add your comments to this post or one of the others on this blog that target specific features of the Entity Framework. This is a direct connection to the people who designed the Entity Framework. You can get answers to your questions and save time getting past the difficulties of working with new technology. The questions you raise will generate a lot of discussion at Microsoft. You'll get fast answers and help us make the next release of the Entity Framework easier to use.

Are there any particular features of the Entity Framework that need more documentation? In order to implement the examples in the documentation, the writers on this project resolved many of the coding issues you will encounter as you experiment with this framework. How can we make it easier for you to understand schema syntax and application code?

Tell us about the data applications you want to implement. Which scenarios for using this framework interest you most? The entity data model exists to increase your productivity. Using this model, you can resolve data access issues and concentrate directly on application scenarios. Tell us how we can help you get started. Your questions will get fast answers, and your feedback will improve the next release of the Entity Framework.

Mike Dodaro

Programmer/ Writer

Comments

  • Anonymous
    April 20, 2007
    Hi, I would like to know when will the EDM Designer be released? I can't find it in Beta 1... Thanks, Guy Burstein

  • Anonymous
    April 21, 2007
    Does Visual Studio Orcas Express Editions have full support for ADO.NET Entity Framework, including desiging tools?

  • Anonymous
    April 21, 2007
    I am interested how it is possilbe to implement paging functionality using LINQ to SQL For example: int totalRecordsCount; INumerable<Product> products = from p in db.Products                                                      where p.Name.StartsWith("A")                                                      select p                                                      limit(0, 10),                                                      out totalRecordsCount;

  • Anonymous
    April 21, 2007
    When I add an ADO.NET EDM file to my project and select the tables from my schema, I get nothing but an empty .csdl file.  No entities are mapped or generated.  It makes no difference how many tables I select.  The March CTP was at least stable enough to generate a functional EDM from a relational DB, what happened with Beta 1?

  • Anonymous
    April 21, 2007
    Using the C# Express Beta 1 I am having similar experiences to what others have said. I can't find any type of designer. In addition, my .csdl files are essentially blank. They contain no mapped entities.

  • Anonymous
    April 21, 2007
    This is bad... Very, very bad... Even the walkthroughs in the documentation are producing empty csdl files.   I can generate a mapping schema manually using the System.Data.Entity.Design namespace, but when I run the class generator against the csdl file ( Runtime Version:2.0.50727.1304), I get the following error: Error 4 Custom tool error: The element Schema in namespace http://schemas.microsoft.com/ado/2006/04/edm/ssdl">http://schemas.microsoft.com/ado/2006/04/edm/ssdl was unexpected for the root element. Expected Schema in namespace http://schemas.microsoft.com/ado/2006/04/edm. C:DevsrcZentitiesWindowsApplication1Model1.csdl 1 1 WindowsApplication1 I'm building smart-client using sync-services with SqlCE, (but I run the EDM wizard against a SQLServer '05 DB), I cannot circumvent the need for EDM as it comprises my primary data layer on both the client and server modules. After spending the better part of a day un-installing the March CTP and getting Beta 1 configured, I would hate to think any of the following are true: 1: I have to go back to the quircky March CTP to continue working. 2: I have to manual write pages upon pages of XML to create my own EDM which I would have to manually maintain and update whenever my data model changes. Please, please, please address this ASAP!  My entire data layer is riding on this! Thanks for all your great work!!!

  • Anonymous
    April 21, 2007
    The console Utility (EdmGen.exe) still works so I'm guessing it's an issue with the IDE.

  • Anonymous
    April 21, 2007
    As others have pointed out, the Orcas Beta 1 EDM wizard generates almost blank files. I tried doing the quickstart from the documentation but can't generate the model using the IDE wizard.

  • Anonymous
    April 21, 2007
    The comment has been removed

  • Anonymous
    April 22, 2007
    Bigger issue here: SQL Server Compact Edition + Server Explorer: When creating or opening a connection: "Unable to find the requested .NET Framework Data Provider.  It may not be installed." "Test Connection" returns "Successful", and I can also connect to SSCE programmatically. I did have a previous version of Orcas (March CTP) installed which I removed.  I uninstalled everything related to VS as per the instructions here: http://download.microsoft.com/download/9/f/7/9f79d1d8-72fd-407c-88f7-d2254eb4e0ad/VSNETSDKcontents.htm Then re-installed the Beta 1 release. There was no change to the behavior:   "Unable to find the requested .NET Framework Data Provider.  It may not be installed." I followed the instructions regarding the machine.config fix/workaround as detailed here: http://oakleafblog.blogspot.com/2007/03/orcas-march-ctp-on-vista-database.html I am unable to integrate Sync Services without connecting  to SSCE.  This issue was not present in the March CTP. Can you confirm this is a problem with the beta release?

  • Anonymous
    April 22, 2007
    The EDMGen tool does not generate properties for fields of type image or text, are they not supported yet?

  • Anonymous
    April 22, 2007
    Support for sql_variant is missing, is this in works or are you not going to support it in v1?

  • Anonymous
    April 22, 2007

  1. A "What's New in Beta 1" post, similar to that by the XML Team is needed (see http://blogs.msdn.com/xmlteam/archive/2007/04/20/linq-to-xml-changes-in-orcas-beta1.aspx).
  2. A detailed known bugs list is an absolute necessity, with estimates of when the bugs might be fixed.
  3. Your Iintention to provide interim CTPs for fixes and missing features needs to be spelled out. --rj

  • Anonymous
    April 22, 2007
    We discovered late friday that there were some changes in the VS wizard framework for beta 1, and these caused the EDM wizard to generate empty models.  We have a fix coded, and we are working through the logistics of releasing this. Sorry for the inconvenience. Mike Kaufman Microsoft Corp.

  • Anonymous
    April 22, 2007
    Thanks Mike, look forward to it.

  • Anonymous
    April 22, 2007
    The comment has been removed

  • Anonymous
    April 23, 2007
    Where is the documentation?  The version of the MSDN doucmentation that comes with C# express contains essentially no documentation of the entity framework and very little documentation of LINQ as a whole.  The LINQ documentation that has come with earlier CTP's (May 2006)is exceptionally good.  But all I can find for the entity framework are the papers from May and June 2006.  I cannot find any documentation available for download on entity SQL.  It may be in the recent CTP's.  But those are not installable on my Vista machine.

  • Anonymous
    April 23, 2007
    How about documentation on getting it to work with a DB2 database?

  • Anonymous
    April 23, 2007
    Mesan, We are working closely with many DB vendors, including IBM, to help them update their ADO.NET providers to support the Entity Framework.  Unfortunately, I do not have any information as to when they may release a new provider. Thank you, Elisa Johnson Program Manager, Microsoft Data Programmability

  • Anonymous
    April 23, 2007
    Some of these questions are beyond the scope of this post.  Installation issues may be resolved faster by posting to the ADO.NET Forum.  The forum can be found at the following url: http://forums.microsoft.com/MSDN/ShowForum.aspx?ForumID=533&SiteID=1

  • Anonymous
    April 23, 2007
    The Entity Framework documentation is not included in installations of the Express edition of Orcas Beta 1.  To get the compete documentation install the Orcas SKU from here : http://msdn2.microsoft.com/en-us/vstudio/default.aspx In a few days the documentation for ADO.NET and Entity Framework should be available on MSDN.  Current ETA: Wednesday, April 25, 2007.

  • Anonymous
    April 24, 2007
    The ADO.NET documentation is now available on MSDN at the following url: http://msdn2.microsoft.com/en-us/library/e80y5yhx(VS.90).aspx

  • Anonymous
    April 25, 2007
    So it seems that as of Orcas beta one the express editions basically do not support linq for entities.  The samples can be compiled and work.  But the tool for building the mapping and schema files (edmGen.exe) is not included.  Is this the release plan?

  • Anonymous
    April 26, 2007
    Hi David - For Orcas Beta1, edmgen.exe should be at "%windir%Microsoft.netFrameworkv3.5.20404edmgen.exe" Can you check to see if it is in that location? Thanks, Mike

  • Anonymous
    April 28, 2007
    I would like to see a sample for hosting a WCF service exposing the Entity layer for AdventureWorks.

  • Anonymous
    May 09, 2007
    Beside Project "Astoria" we also announced Project code named "Jasper" at Mix07 last week. Project Codename

  • Anonymous
    May 19, 2007
    The comment has been removed

  • Anonymous
    May 19, 2007
    Oh yeah... Project Astoria looks amazing, BTW. All I can say is WOW! This is the first I've heard of it. Scott Lloyd Lloyd Software Development

  • Anonymous
    May 30, 2007
    I have a feature request for LINQ to Entities. Please add composability of ObjectQuery upon ObjectQuery, just like IQueryable upon IQueryable. I need to be able to extend the final query (that goes to the database) using LINQ to Entities. Following is an example of what I'm talking about. If I have the following tables:   Orders and OrderDetails I can define a LINQ to SQL query like this   var qry = from r1 in db.Orders           from r2 in db.OrderDetails           where r1.orderid == r2.orderid           select r1.orderid; But also can define the following extension query in a partial class that has the same name as the DataContext. This way this new method becomes an extension to the model and looks just as natural as the other tables with the exception that is a method and not a property: public partial class Northwind {   public IQueryable<Orders> ValidOrders( System.DateTime pFrom, System.DateTime pThrough )   {      return from row in this.Orders             where orderdate >= pFrom             && orderdate <= pThrough             select row;   } } and I can use it as a table in a query: var qry = from r1 in db.ValidOrders( DateTime.Parse("1/1/2006"), DateTime.Parse("12/31/2006") )           from r2 in db.OrderDetails           where r1.orderid == r2.orderid           select r1.orderid; I can NOT do that with Entities and I really think this is necessary to create tables that enforce some data level business logic and simplify programming like Views, but that are not subjected to the same restrictions (i.e. View of a join of multiple tables that accepts INSERT).

  • Anonymous
    June 19, 2007
    I saw a question over here about "How do I implement paging of data in LINQ to SQL". For me, this...

  • Anonymous
    September 16, 2009
    I second "megame's" request for sql_variant support in EF 4.  We have to use LINQ-to-SQL to access sql_variants but rest of our code base is based on EF.  As you can imagine, having to use both LINQ-to-SQL and LINQ-to-Entities day-to-day is enough to drive a developer mad.  So please add sql_variant (to object) to EF 4 before RTM.  And also please ASAP combine LINQ-to-SQL and LINQ-to-Entities to end the madness and confusion out there about which to use when. Thanks! -Andy