Entity Framework Core tools reference - .NET CLI

The command-line interface (CLI) tools for Entity Framework Core perform design-time development tasks. For example, they create migrations, apply migrations, and generate code for a model based on an existing database. The commands are an extension to the cross-platform dotnet command, which is part of the .NET Core SDK. These tools work with .NET Core projects.

If you're using Visual Studio, we recommend the Package Manager Console tools instead:

  • They automatically work with the current project selected in the Package Manager Console without requiring that you manually switch directories.
  • They automatically open files generated by a command after the command is completed.

Installing the tools

The installation procedure depends on project type and version:

  • ASP.NET Core version 2.1 and later
  • EF Core 2.x
  • EF Core 1.x

ASP.NET Core 2.1+

  • Install the current .NET Core SDK. The SDK has to be installed even if you have the latest version of Visual Studio 2017.

    This is all that is needed for ASP.NET Core 2.1+ because the Microsoft.EntityFrameworkCore.Design package is included in the Microsoft.AspNetCore.App metapackage.

EF Core 2.x (not ASP.NET Core)

The dotnet ef commands are included in the .NET Core SDK, but to enable the commands you have to install the Microsoft.EntityFrameworkCore.Design package.

  • Install the current .NET Core SDK. The SDK has to be installed even if you have the latest version of Visual Studio 2017.

  • Install the latest stable Microsoft.EntityFrameworkCore.Design package.

    dotnet add package Microsoft.EntityFrameworkCore.Design
    

EF Core 1.x

  • Install the .NET Core SDK version 2.1.200. Later versions are not compatible with CLI tools for EF Core 1.0 and 1.1.

  • Configure the application to use the 2.1.200 SDK version by modifying its global.json file. This file is normally included in the solution directory (one above the project).

  • Edit the project file and add Microsoft.EntityFrameworkCore.Tools.DotNet as a DotNetCliToolReference item. Specify the latest 1.x version, for example: 1.1.6. See the project file example at the end of this section.

  • Install the latest 1.x version of the Microsoft.EntityFrameworkCore.Design package, for example:

    dotnet add package Microsoft.EntityFrameworkCore.Design -v 1.1.6
    

    With both package references added, the project file looks something like this:

    <Project Sdk="Microsoft.NET.Sdk">
      <PropertyGroup>
        <OutputType>Exe</OutputType>
        <TargetFramework>netcoreapp1.1</TargetFramework>
      </PropertyGroup>
      <ItemGroup>
        <PackageReference Include="Microsoft.EntityFrameworkCore.Design"
                          Version="1.1.6"
                           PrivateAssets="All" />
      </ItemGroup>
      <ItemGroup>
         <DotNetCliToolReference Include="Microsoft.EntityFrameworkCore.Tools.DotNet"
                                Version="1.1.6" />
      </ItemGroup>
    </Project>
    

    A package reference with PrivateAssets="All" isn't exposed to projects that reference this project. This restriction is especially useful for packages that are typically only used during development.

Verify installation

Run the following commands to verify that EF Core CLI tools are correctly installed:

dotnet restore
dotnet ef

The output from the command identifies the version of the tools in use:


                     _/\__
               ---==/    \\
         ___  ___   |.    \|\
        | __|| __|  |  )   \\\
        | _| | _|   \_/ |  //|\\
        |___||_|       /   \\\/\\

Entity Framework Core .NET Command-line Tools 2.1.3-rtm-32065

<Usage documentation follows, not shown.>

Using the tools

Before using the tools, you might have to create a startup project or set the environment.

Target project and startup project

The commands refer to a project and a startup project.

  • The project is also known as the target project because it's where the commands add or remove files. By default, the project in the current directory is the target project. You can specify a different project as target project by using the --project option.

  • The startup project is the one that the tools build and run. The tools have to execute application code at design time to get information about the project, such as the database connection string and the configuration of the model. By default, the project in the current directory is the startup project. You can specify a different project as startup project by using the --startup-project option.

The startup project and target project are often the same project. A typical scenario where they are separate projects is when:

  • The EF Core context and entity classes are in a .NET Core class library.
  • A .NET Core console app or web app references the class library.

It's also possible to put migrations code in a class library separate from the EF Core context.

Other target frameworks

The CLI tools work with .NET Core projects and .NET Framework projects. Apps that have the EF Core model in a .NET Standard class library might not have a .NET Core or .NET Framework project. For example, this is true of Xamarin and Universal Windows Platform apps. In such cases, you can create a .NET Core console app project whose only purpose is to act as startup project for the tools. The project can be a dummy project with no real code — it is only needed to provide a target for the tooling.

Why is a dummy project required? As mentioned earlier, the tools have to execute application code at design time. To do that, they need to use the .NET Core runtime. When the EF Core model is in a project that targets .NET Core or .NET Framework, the EF Core tools borrow the runtime from the project. They can't do that if the EF Core model is in a .NET Standard class library. The .NET Standard is not an actual .NET implementation; it's a specification of a set of APIs that .NET implementations must support. Therefore .NET Standard is not sufficient for the EF Core tools to execute application code. The dummy project you create to use as startup project provides a concrete target platform into which the tools can load the .NET Standard class library.

ASP.NET Core environment

To specify the environment for ASP.NET Core projects, set the ASPNETCORE_ENVIRONMENT environment variable before running commands.

Common options

Option Description
--json Show JSON output.
-c --context <DBCONTEXT> The DbContext class to use. Class name only or fully qualified with namespaces. If this option is omitted, EF Core will find the context class. If there are multiple context classes, this option is required.
-p --project <PROJECT> Relative path to the project folder of the target project. Default value is the current folder.
-s --startup-project <PROJECT> Relative path to the project folder of the startup project. Default value is the current folder.
--framework <FRAMEWORK> The Target Framework Moniker for the target framework. Use when the project file specifies multiple target frameworks, and you want to select one of them.
--configuration <CONFIGURATION> The build configuration, for example: Debug or Release.
--runtime <IDENTIFIER> The identifier of the target runtime to restore packages for. For a list of Runtime Identifiers (RIDs), see the RID catalog.
-h --help Show help information.
-v --verbose Show verbose output.
--no-color Don't colorize output.
--prefix-output Prefix output with level.

dotnet ef database drop

Drops the database.

Options:

Option Description
-f --force Don't confirm.
--dry-run Show which database would be dropped, but don't drop it.

dotnet ef database update

Updates the database to the last migration or to a specified migration.

Arguments:

Argument Description
<MIGRATION> The target migration. Migrations may be identified by name or by ID. The number 0 is a special case that means before the first migration and causes all migrations to be reverted. If no migration is specified, the command defaults to the last migration.

The following examples update the database to a specified migration. The first uses the migration name and the second uses the migration ID:

dotnet ef database update InitialCreate
dotnet ef database update 20180904195021_InitialCreate

dotnet ef dbcontext info

Gets information about a DbContext type.

dotnet ef dbcontext list

Lists available DbContext types.

dotnet ef dbcontext scaffold

Generates code for a DbContext and entity types for a database. In order for this command to generate an entity type, the database table must have a primary key.

Arguments:

Argument Description
<CONNECTION> The connection string to the database. For ASP.NET Core 2.x projects, the value can be name=<name of connection string>. In that case the name comes from the configuration sources that are set up for the project.
<PROVIDER> The provider to use. Typically this is the name of the NuGet package, for example: Microsoft.EntityFrameworkCore.SqlServer.

Options:

Option Description
-d --data-annotations Use attributes to configure the model (where possible). If this option is omitted, only the fluent API is used.
-c --context <NAME> The name of the DbContext class to generate.
--context-dir <PATH> The directory to put the DbContext class file in. Paths are relative to the project directory. Namespaces are derived from the folder names.
-f --force Overwrite existing files.
-o --output-dir <PATH> The directory to put entity class files in. Paths are relative to the project directory.
--schema <SCHEMA_NAME>... The schemas of tables to generate entity types for. To specify multiple schemas, repeat --schema for each one. If this option is omitted, all schemas are included.
-t --table <TABLE_NAME>... The tables to generate entity types for. To specify multiple tables, repeat -t or --table for each one. If this option is omitted, all tables are included.
--use-database-names Use table and column names exactly as they appear in the database. If this option is omitted, database names are changed to more closely conform to C# name style conventions.

The following example scaffolds all schemas and tables and puts the new files in the Models folder.

dotnet ef dbcontext scaffold "Server=(localdb)\mssqllocaldb;Database=Blogging;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -o Models

The following example scaffolds only selected tables and creates the context in a separate folder with a specified name:

dotnet ef dbcontext scaffold "Server=(localdb)\mssqllocaldb;Database=Blogging;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -o Models -t Blog -t Post --context-dir Context -c BlogContext

dotnet ef migrations add

Adds a new migration.

Arguments:

Argument Description
<NAME> The name of the migration.

Options:

Option Description
-o --output-dir <PATH> The directory (and sub-namespace) to use. Paths are relative to the project directory. Defaults to "Migrations".

dotnet ef migrations list

Lists available migrations.

dotnet ef migrations remove

Removes the last migration (rolls back the code changes that were done for the migration).

Options:

Option Description
-f --force Revert the migration (roll back the changes that were applied to the database).

dotnet ef migrations script

Generates a SQL script from migrations.

Arguments:

Argument Description
<FROM> The starting migration. Migrations may be identified by name or by ID. The number 0 is a special case that means before the first migration. Defaults to 0.
<TO> The ending migration. Defaults to the last migration.

Options:

Option Description
-o --output <FILE> The file to write the script to.
-i --idempotent Generate a script that can be used on a database at any migration.

The following example creates a script for the InitialCreate migration:

dotnet ef migrations script 0 InitialCreate

The following example creates a script for all migrations after the InitialCreate migration.

dotnet ef migrations script 20180904195021_InitialCreate

Additional resources