Entity Framework 6 SQL Server provider based on Microsoft.Data.SqlClient

This Entity Framework 6 provider is a replacement provider for the built-in SQL Server provider.

This provider depends on the modern Microsoft.Data.SqlClient ADO.NET provider, see my blog post here for why that can be desirable.

The latest build of this package is available from NuGet

Configuration

There are various ways to configure Entity Framework to use this provider.

You can register the provider in code using an attribute:

    [DbConfigurationType(typeof(MicrosoftSqlDbConfiguration))]
    public class SchoolContext : DbContext
    {
        public SchoolContext() : base()
        {
        }

        public DbSet<Student> Students { get; set; }
    }

If you have multiple classes inheriting from DbContext in your solution, add the DbConfigurationType attribute to all of them.

Or you can use the SetConfiguration method before any data access calls:

 DbConfiguration.SetConfiguration(new MicrosoftSqlDbConfiguration());

Or you can add the following lines to your existing DbConfiguration class:

SetProviderFactory(MicrosoftSqlProviderServices.ProviderInvariantName, Microsoft.Data.SqlClient.SqlClientFactory.Instance);
SetProviderServices(MicrosoftSqlProviderServices.ProviderInvariantName, MicrosoftSqlProviderServices.Instance);
// Optional
SetExecutionStrategy(MicrosoftSqlProviderServices.ProviderInvariantName, () => new MicrosoftSqlAzureExecutionStrategy());

You can also use XML/App.Config based configuration:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <configSections>
        <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />    
    </configSections>
    <entityFramework>
        <providers>		
            <provider invariantName="Microsoft.Data.SqlClient" type="System.Data.Entity.SqlServer.MicrosoftSqlProviderServices, ErikEJ.EntityFramework.SqlServer" />
        </providers>
    </entityFramework>
    <system.data>
        <DbProviderFactories>
           <add name="SqlClient Data Provider"
             invariant="Microsoft.Data.SqlClient"
             description=".NET Framework Data Provider for SqlServer"
             type="Microsoft.Data.SqlClient.SqlClientFactory, Microsoft.Data.SqlClient" />
        </DbProviderFactories>
    </system.data>
</configuration>

If you use App.Config with a .NET Core / .NET 5 or later app, you must register the DbProviderFactory in code once:

DbProviderFactories.RegisterFactory(MicrosoftSqlProviderServices.ProviderInvariantName, Microsoft.Data.SqlClient.SqlClientFactory.Instance);

EDMX usage

If you use an EDMX file, update the Provider name:

<edmx:Edmx Version="3.0" xmlns:edmx="http://schemas.microsoft.com/ado/2009/11/edmx">
  <edmx:Runtime>
    <edmx:StorageModels>
      <Schema Namespace="ChinookModel.Store" Provider="Microsoft.Data.SqlClient" >

In order to use the EDMX file with the Visual Studio designer, you must switch the provider name back to System.Data.SqlClient

Also update the provider name inside the EntityConnection connection string:

 <add 
    name="Database" 
    connectionString="metadata=res://*/EFModels.csdl|res://*/EFModels.ssdl|res://*/EFModels.msl;provider=Microsoft.Data.SqlClient;provider connection string=&quot;data source=server;initial catalog=mydb;integrated security=True;persist security info=True;" 
    providerName="System.Data.EntityClient" 
 />

Code changes

In order to use the provider in an existing solution, a few code changes are required (as needed).

using System.Data.SqlClient; => using Microsoft.Data.SqlClient;

The following classes have been renamed to avoid conflicts with classes in the existing SQL Server provider:

SqlAzureExecutionStrategy => MicrosoftSqlAzureExecutionStrategy

SqlConnectionFactory => MicrosoftSqlConnectionFactory

SqlDbConfiguration => MicrosoftSqlDbConfiguration

SqlProviderServices => MicrosoftSqlProviderServices

SqlServerMigrationSqlGenerator => MicrosoftSqlServerMigrationSqlGenerator

Known issues

Microsoft.SqlServer.Types not currently supported

Use of DbGeography, DbGeometry and HierarchyId is not currently supported, see discussion here

EntityFramework.dll installed in GAC

If an older version of EntityFramework.dll is installed in the .NET Framework GAC (Global Assembly Cache), you might get this error:

The 'PrimitiveTypeKind' attribute is invalid - The value 'HierarchyId' is invalid according to its datatype

Solution is to remove the .dll from the GAC, see this for more info

Feedback

Please report any issues, questions and suggestions here

Release notes

6.5.x

• Uses Microsoft.Data.SqlClient 4.0.1
• Removed spatial and MicrosoftSqlFunctions classes

6.4.x

• Uses Microsoft.Data.SqlClient 2.1.4