Entity Framework 6 Support for Oracle, MySQL, PostgreSQL, SQLite, DB2 and Salesforce

Article was updated on December 5th, 2013

Entity Framework 6 Alpha 2 support is implemented in Devart ADO.NET providers: dotConnect for Oracle, dotConnect for MySQL, dotConnect for PostgreSQL, dotConnect for SQLite, dotConnect for DB2 and dotConnect for Salesforce. You need to download the corresponding Entity Framework NuGet package to use it in your applications. You can read about Entity Framework 6 features in the corresponding MSDN articles.

• New Assemblies
  • Code-First Migrations
  • Entity Framework Spatials Support
• Provider Registration
  • Config File Registration
    • Registration in entityFramework Section
    • DbProviderFactory Registration
    • Registration Examples
  • Registration of Entity Framework Code-First Migrations
  • Code-based Registration
    • New Registration Classes
    • Code-based Registration Examples
• Migrating Projects from Entity Framework v4/v5
  • Entity Developer
  • Code-First or Entity Data Model Designer
  • Obsolete Workarounds
    • Using Non-Unicode Strings
    • Using Non-LOB Strings
    • Using DATE fields instead of TIMESTAMP
• Samples
• Conclusion

New Assemblies

In order to support Entity Framework 6, we have included new assemblies compiled under .NET Framework 4.0 to the installation packages of our providers. We have added the revision number “6” to the assembly versions to easily distinguish them from the corresponding Entity Framework v4/v5 assemblies.

I.e., if a Devart.Data.Xxx.Entity.dll assembly for Entity Framework v4/v5 has the “7.4.147.0” version number, the corresponding Entity Framework 6 assembly will have the “7.4.147.6” version.

Entity Framework 6 support assemblies are installed to the GAC and to the provider installation folder (by default to %Program Files%\Devart\dotConnect\Xxx\Entity\EF6 where Xxx can be ‘Oracle’, ‘MySQL’, ‘PostgreSQL’, ‘SQLite’, ‘DB2’ or ‘Salesforce’).

Code-First Migrations

With the release of Entity Framework 6 there is no more need to place Code-First Migrations functionality in a separate assembly, so there are no more Devart.Data.Xxx.Entity.Migrations.dll assemblies. Code-First Migrations functionality is integrated to the main Devart.Data.Xxx.Entity.dll Entity Framework assembly.

Entity Framework Spatials Support

Entity Framework Spatials are currently supported only in Devart dotConnect for Oracle.

Spatials support was first introduced in Entity Framework 5 on .NET Framework 4.5. Now, with the release of Entity Framework 6, we have supported Entity Framework Spatials for .NET Framework 4.0 too.

There is also an additional Devart.Data.Oracle.Entity.SharpMap.dll assembly, compiled for .NET Framework 4.0, to support the SharpMap library.

For more details on Spatials support see the “Using Entity Framework Spatials with Oracle Spatial and SharpMap” blog article.

Provider Registration

Entity Framework provider registration has been changed in Entity Framework 6. In earlier versions of Entity Framework it’s enough to register DbProviderFactory in the machine.config or application config file. Now you need to perform some additional actions. You can register an Entity Framework provider in two ways: using config file registration or сode-based registration.

Config File Registration

Registration in entityFramework Section

After you install the EntityFramework 6 NuGet package, the following lines will be added to your application config file:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  </configSections>
  <entityFramework>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.SqlConnectionFactory, EntityFramework" />
  </entityFramework>
</configuration>

You need to remove the defaultConnectionFactory registration add to add the Entity Framework provider registration by registering it in the entityFramework section. Here is the example, registering Devart dotConnect for Oracle:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
    <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="Devart.Data.Oracle" type="Devart.Data.Oracle.Entity.OracleEntityProviderServices, Devart.Data.Oracle.Entity, Version=7.4.147.6, Culture=neutral, PublicKeyToken=09af7300eec23701" />        
    </providers>  
  </entityFramework>
</configuration>

Note: Don’t forget to replace ‘7.4.147.6’ with the actual Entity Framework provider assembly version.

DbProviderFactory Registration

When our provider is installed, it automatically places provider registration record to the DbProviderFactories section in the global machine.config file, and there is no need to duplicate it in the local application config file, while the application is developed and tested locally. However, to deploy your application, you need to register the Entity Framework provider in the DbProviderFactories section. Here is an example, registering Devart dotConnect for Oracle:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
    <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="Devart.Data.Oracle" type="Devart.Data.Oracle.Entity.OracleEntityProviderServices, Devart.Data.Oracle.Entity, Version=7.4.147.6, Culture=neutral, PublicKeyToken=09af7300eec23701" />
    </providers>
  </entityFramework>
  <system.data>
    <DbProviderFactories>
      <remove invariant="Devart.Data.Oracle" />
      <add name="dotConnect for Oracle" invariant="Devart.Data.Oracle" description="Devart dotConnect for Oracle"
       type="Devart.Data.Oracle.OracleProviderFactory, Devart.Data.Oracle, Version=7.4.147.0, Culture=neutral, PublicKeyToken=09af7300eec23701" />
    </DbProviderFactories>
  </system.data>
</configuration>

Note: Don’t forget to replace ‘7.4.147.0’ with the actual provider assembly version.

Registration Examples

The registration is similar for other dotConnect providers. Here is an example, registering all our Entity Framework providers – for Oracle, MySQL, PostgreSQL, SQLite, DB2 and Salesforce:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
  <configSections>
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
    <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="Devart.Data.Oracle" type="Devart.Data.Oracle.Entity.OracleEntityProviderServices, Devart.Data.Oracle.Entity, Version=7.4.147.6, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <provider invariantName="Devart.Data.MySql" type="Devart.Data.MySql.Entity.MySqlEntityProviderServices, Devart.Data.MySql.Entity, Version=7.3.147.6, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <provider invariantName="Devart.Data.PostgreSql" type="Devart.Data.PostgreSql.Entity.PgSqlEntityProviderServices, Devart.Data.PostgreSql.Entity, Version=6.3.147.6, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <provider invariantName="Devart.Data.SQLite" type="Devart.Data.SQLite.Entity.SQLiteEntityProviderServices, Devart.Data.SQLite.Entity, Version=4.3.147.6, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <provider invariantName="Devart.Data.DB2" type="Devart.Data.DB2.Entity.DB2EntityProviderServices, Devart.Data.DB2.Entity, Version=1.6.146.6, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <provider invariantName="Devart.Data.Salesforce" type="Devart.Data.Salesforce.Entity.SalesforceEntityProviderServices, Devart.Data.Salesforce.Entity, Version=2.1.35.6, Culture=neutral, PublicKeyToken=09af7300eec23701" />
    </providers>
  </entityFramework>
  <system.data>
    <DbProviderFactories>
      <remove invariant="Devart.Data.Oracle" />
      <add name="dotConnect for Oracle" invariant="Devart.Data.Oracle" description="Devart dotConnect for Oracle"
       type="Devart.Data.Oracle.OracleProviderFactory, Devart.Data.Oracle, Version=7.4.147.0, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <remove invariant="Devart.Data.MySql" />
      <add name="dotConnect for MySQL" invariant="Devart.Data.MySql" description="Devart dotConnect for MySQL"
       type="Devart.Data.MySql.MySqlProviderFactory, Devart.Data.MySql, Version=7.3.147.0, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <remove invariant="Devart.Data.PostgreSql" />
      <add name="dotConnect for PostgreSQL" invariant="Devart.Data.PostgreSql" description="Devart dotConnect for PostgreSQL"
       type="Devart.Data.PostgreSql.PgSqlProviderFactory, Devart.Data.PostgreSql, Version=6.3.147.0, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <remove invariant="Devart.Data.SQLite" />
      <add name="dotConnect for SQLite" invariant="Devart.Data.SQLite" description="Devart dotConnect for SQLite"
       type="Devart.Data.SQLite.SQLiteProviderFactory, Devart.Data.SQLite, Version=4.3.147.0, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <remove invariant="Devart.Data.DB2" />
      <add name="dotConnect for DB2" invariant="Devart.Data.DB2" description="Devart dotConnect for DB2"
       type="Devart.Data.DB2.DB2ProviderFactory, Devart.Data.DB2, Version=1.6.146.0, Culture=neutral, PublicKeyToken=09af7300eec23701" />
      <remove invariant="Devart.Data.Salesforce" />
      <add name="dotConnect for Salesforce" invariant="Devart.Data.Salesforce" description="Devart dotConnect for Salesforce"
       type="Devart.Data.Salesforce.SalesforceProviderFactory, Devart.Data.Salesforce, Version=2.1.35.0, Culture=neutral, PublicKeyToken=09af7300eec23701" />
    </DbProviderFactories>
  </system.data>
</configuration>

Registration of Entity Framework Code-First Migrations

To register migration SQL generator for Code-First Migrations, use the SetSqlGenerator method of the DbMigrationsConfiguration descendant for Entity Framework 6.

internal sealed class Configuration : DbMigrationsConfiguration {
    public Configuration() {
        AutomaticMigrationsEnabled = false; 
        this.SetSqlGenerator(OracleConnectionInfo.InvariantName, new OracleEntityMigrationSqlGenerator());
    }
    // ...
}

Code-based Registration

Entity Framework provider can be registered with the special DbConfigurationType attribute or with the static SetConfiguration method of the new DbConfiguration class. You need to path a specially configured DbConfiguration descendant to this method.

New Registration Classes

To ease code-based registration, we have included new DbConfiguration descendants to our Entity Framework providers:

ProviderAssemblyClass Name

Code-based Registration Examples

dotConnect for Oracle Entity Framework provider registration with the DbConfigurationType attribute (can be used for DbContext only):

  [DbConfigurationType(typeof(Devart.Data.Oracle.Entity.OracleEntityProviderServicesConfiguration))]
  public class MyContext : DbContext {

    // ...
  }

dotConnect for Oracle Entity Framework provider registration with the static SetConfiguration method of the new DbConfiguration class (can be used for both DbContext and ObjectContext):

  public class MyContext: ObjectContext {

    static MyContext() {

      DbConfiguration.SetConfiguration(new Devart.Data.Oracle.Entity.OracleEntityProviderServicesConfiguration());
    }

    // ...
  }

If you have installed our Entity Framework provider, machine.config already contain the provider registration record in the DbProviderFactories section, and you don’t need to duplicate it in the local application config file while the application is developed and tested locally. You can use only code-based registration during development time.

However, when you deploy your project, you need to register the Entity Framework provider in the DbProviderFactories of the application config file, like it is described above in the DbProviderFactory Registration section.

Migrating Projects from Entity Framework v4/v5

To migrate your project from Entity Framework v4/v5 to Entity Framework v6 perform the following steps:

1. Install EntityFramework 6. For example, you can do it with the following command in Package Manager Console:

   Install-Package EntityFramework -Pre

2. Remove references to old assemblies, specific to Entity Framework v4/v5 from the project:
   • System.Data.Entity.dll
   • Devart.Data.Xxx.Entity.dll
   • Devart.Data.Xxx.Entity.Migrations.dll (for Oracle, MySQL, PostgreSQL, or SQLite)
   • Devart.Data.Oracle.Entity.SharpMap.dll (for Oracle)
3. Add references to new, Entity Framework 6 compatible, assemblies to the project:
   • Devart.Data.Xxx.Entity.dll
   • Devart.Data.Oracle.Entity.SharpMap.dll (for Oracle if you use Oracle Spatials and SharpMap)
4. Register Entity Framework provider with one of the ways described above

Entity Developer

For Entity Developer users migration is very simple – just change Entity Framework Version option to “Entity Framework 6” in Model Settings. After this close the model and open it in Entity Developer again. Entity Developer will generate valid code, compatible with Entity Framework 6.

Currently if you use standalone Entity Developer (not the one integrated to the Visual Studio), you need to manually add the EntityFramework.dll assembly to the GAC of .NET Framework 4.0 (4.5) or to place this assembly to the directory where Entity Developer is installed. This is not required, however some Entity Developer features may not work correctly for Entity Framework 6 models without it. We plan to overcome this limitation in future releases.

Code-First or Entity Data Model Designer

See Microsoft recommendations on migration to Entity Framework 6.

Obsolete Workarounds

Entity Framework 6 introduces custom conventions including lightweight conventions. This makes the following Devart dotConnect for Oracle properties obsolete and not recommended to use:

• config.CodeFirstOptions.UseNonUnicodeStrings
• config.CodeFirstOptions.UseNonLobStrings
• config.CodeFirstOptions.UseDateTimeAsDate

These are settings used for workarounds, related to configuring property mapping when the explicit definition of mapping is incomplete.

Here are the examples how to replace these options in a way, recommended in Entity Framework 6.

Using Non-unicode Strings

A simple lightweight convention can be used instead of the config.CodeFirstOptions.UseNonUnicodeStrings property.

  public class MyContext : DbContext {

    protected override void OnModelCreating(DbModelBuilder modelBuilder) {

      modelBuilder
        .Properties()
        .Where(p => p.PropertyType == typeof(string))
        .Configure(p => p.IsUnicode(false));
    }

    // ...
  }

This convention makes all the string properties non-unicode.

Using Non-LOB Strings

Instead of the config.CodeFirstOptions.UseNonLobStrings property, you can use the following lightweight convention.

  public class MyContext : DbContext {

    protected override void OnModelCreating(DbModelBuilder modelBuilder) {

      modelBuilder
        .Properties()
        .Where(p => p.PropertyType == typeof(string) && 
                    p.GetCustomAttributes(typeof(MaxLengthAttribute), false).Length == 0)
        .Configure(p => p.HasMaxLength(2000));
    }

    // ...
  }

This convention sets MaxLength to 2000 characters for all string properties, which don’t have MaxLength set explicitly with the MaxLengthAttribute attribute.

Using DATE fields instead of TIMESTAMP

You can use the following simple lightweight convention instead of the config.CodeFirstOptions.UseDateTimeAsDate property.

  public class MyContext : DbContext {

    protected override void OnModelCreating(DbModelBuilder modelBuilder) {

      modelBuilder
        .Properties()
        .Where(p => p.PropertyType == typeof(DateTime))
        .Configure(p => p.HasPrecision(0));
    }

    // ...
  }

This convention sets zero precision for all DateTime properties. This makes Oracle use DATE type instead of TIMESTAMP(7) because DATE does not store fractions of seconds.

Samples

Here you can download the archive with the Entity Framework 6 version of Code-First samples CrmDemo.EF6CodeFirst_.zip. In this archive you can find the full version of the above examples that use EF Code-First for each ADO.NET provider:

• Devart dotConnect for Oracle
• Devart dotConnect for MySQL
• Devart dotConnect for PostgreSQL
• Devart dotConnect for SQLite
• Devart dotConnect for DB2
• as well as for standard Microsoft .NET Framework Data Provider for SQL Server (SqlClient)

Conclusion

We are glad to provide the new Entity Framework provider functionality – support for Entity Framework 6 – to our users. We hope that you will not have any difficulties migrating to Entity Framework 6. In any case, we are glad to help our users if they have any troubles with migration. As for our future plans on Entity Framework provider development, they are determined largely by your feedback and suggestions via product feedback pages, forum and UserVoice.