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---+++Creating an ADO.Net Data Service

An ADO.Net Data Service for the Oracle tables can be created using the Entity Data Model created in the [[VirtOracleEDM][Creating EDM in Visual Studio 2008]] section. 

   1 Open the <b><nop>VirtuosoDataService</b> project created in the [[VirtOracleEDM][Creating EDM in Visual Studio 2008]] section.%BR%%BR%    
   1 Right click on the <b><nop>VirtuosoDataService</b> project name of the <b>Solution Explorer</b> pane, then select the <b>Add</b> -> <b>New Item</b> menu options.
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   1 The <b>Add New Item</b> dialog will appear. Choose the <b>ADO.NET Data Service</b> template. Give it the name <b>Virtuoso.svc</b> and click <b>Add</b> to create the ADO.Net Data Service.
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   1 In the newly created <b>Virtuoso.svc.cs</b> Data Service file, add the data source class name of <b><nop>VirtuosoEntities</b> (note this is the name set in the Creating EDM in Visual Studio 2008 section) as the <b><nop>DataService</b> name. Then, enable access to the Data Service by adding the entry <b>config.<nop>SetEntitySetAccessRule("*", <nop>EntitySetRights.All);</b> in the <b><nop>InitializeService</b> method. 
<verbatim>

// C#

using System;
using System.Web;
using System.Collections.Generic;
using System.ServiceModel.Web;
using System.Linq;
using System.Data.Services;

namespace SimpleDataService
{
    public class Northwind : DataService<VirtuosoDemoEntities>
    {
        public static void InitializeService(IDataServiceConfiguration  config)
        {
            config.SetEntitySetAccessRule("*", EntitySetRights.All);
        }
    }
}

</verbatim>
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   1 To test the Data Service, simply hit <b>Ctrl+F5</b> within Visual Studio. This will start the development web server, run the Data Services server inside, and load a Web browser page displaying the list of available tables/entities in the HR database catalog.  
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   1 To access a specific entity instance like the <b>EMPLOYEES</b> table employee number <b>100</b> record, use this convention <b>http://host/vdir/Virtuoso.svc/EMPLOYEES(100) </b> .
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---+++NOTES

   1 <b>Important</b> - To view <b>Atom</b> (the default format returned by an ADO.NET Data Service) in Internet Explorer, you must first ensure that <b>Feed Reading View</b> is turned <b>off</b> . This can be done on the <b>Content tab</b> of <b>Tools<b> in <b>Internet Options</b>.%BR%%BR%   
   1 If a Data Services entity instance URI page fails to load, you can turn <b>Verbose</b> errors on by adding <b>config.<nop>UseVerboseErrors = true;</b> in the <b>virtuoso.svc.cs <nop>InitializeService </b> method. This allows you to obtain more detailed information from the server as to why the page failed to load:
<verbatim>

public static void InitializeService(IDataServiceConfiguration config)

{

config.UseVerboseErrors = true;

config.SetEntitySetAccessRule("*", EntitySetRights.All);

}

</verbatim>