LINQ to entities - Error occured update the entries

C# .NET Framework 4.0, Linq to entities

I have an application that uses Linq to entities for accessing to a SQL Server 2008 database, naturally this application works fine. Therefore, I deploy it in a system where there is SQL 2005 express and not SQL Server 2008 and my application gives the follow exception:

Message: An error occurred while updating the entries. See the inner exception for details.

The solution is:

• Open the entity data model, for example Model.edmx, with a XML Editor.
• Change the attribute ProviderManifestToken (Schema element -> <Schema …)

          from

      ProviderManifestToken="2008"

      to

      ProviderManifestToken="2005"

• Rebuild and re-deploy the assembly.

It works fine for me.

Retrieving data from a SQL Server stored procedure using LINQ to entities

C# .NET Framework 4.0, SQL Server 2008, ADO.NET Entity Data Model, LINQ to Entities

I’ve a GetCompanies SQL Server 2008 stored procedure that returns a resultset like this

Field1	Field2	Field3	Field4	Field5	Field6	Field7	Field8
VE	7471	033333333	Environment s.r.l.	1	Roma, 6	Vigonza	35010
VE	7499	033333322	Active s.r.l.	4	Venezia, 8	Padova	35100

So, in my application I want to read this resultset data using LINQ to Entities.

1.       Add a new ADO.NET Entity Data Model (Shapshot.edmx) at the solution.

2.       Follow the wizard for creating a new connection to your database and select the GetCompanies (for this example) stored procedure from the objects list.

3.       Click on Model Browser.

4.       Select the SnapshotModel tree, ComplexTypes.

a.       Right click on CopmplexTypes and then click on “Add new Complex Type”.

b.      Type a name, for example “CompanyEntity”.

                                                               i.      Select CompanyEntity, right click on “Add” -> “Scalar Property” and select the type property: Int32, String, Boolean and so on.

                                                             ii.      In my example I obtain a structure like this

1.       Field1 -> String

2.       Field2 -> Int32

3.       Field3 -> String

4.       Field4 -> String

5.       Field5 -> Int32

6.       Field6 -> String

7.       Field7 -> String

8.       Field8 -> String

c.       Expand the Function Imports folder and double click on GetCompanies stored procedure, you‘ll see a dialog box like this. Select the “Complex” option button and then the type that you have created before.

5.       Now, you can retrieve data using this C# code (Company is an internal object).

GetCompanies() returns a System.Data.Objects.ObjectResult<CompanyEntity> object.

public Company[] GetCompanies()

        {   

            var companiesList = new List<Company>();

            using (var context = new SnapshotEntities())

            {

                var query = context.GetCompanies();

                foreach (var c in query)

                {

                    var company = new Company

                        {

                            Field1 = c.Field1,

                            Field2 = c.Field2,

                            Field3 = c.Field3,

                            Field4 = c.Field4,

                            Field5 = c.Field5,

                            Field6 = c.Field6,

                            Field7 = c.Field7

                            Field8 = c.Field8

                        };

                    companiesList.Add(company);

                }

            }

            return companiesList.ToArray();

        }

That’s all folk!