Entity Framework Core tools reference - .NET Core 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.

When using Visual Studio, consider using the Package Manager Console tools instead of the CLI tools. Package Manager Console tools automatically:

  • Works with the current project selected in the Package Manager Console without requiring that you manually switch directories.
  • Opens files generated by a command after the command is completed.
  • Provides tab completion of commands, parameters, project names, context types, and migration names.

Installing the tools

dotnet ef can be installed as either a global or local tool. Most developers prefer installing dotnet ef as a global tool using the following command:

dotnet tool install --global dotnet-ef

To use it as a local tool, restore the dependencies of a project that declares it as a tooling dependency using a tool manifest file.

Update the tool using the following command:

dotnet tool update --global dotnet-ef

Before you can use the tools on a specific project, you'll need to add the Microsoft.EntityFrameworkCore.Design package to it.

dotnet add package Microsoft.EntityFrameworkCore.Design

Verify installation

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

dotnet ef

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


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

<Usage documentation follows, not shown.>

Update the tools

Use dotnet tool update --global dotnet-ef to update the global tools to the latest available version. If you have the tools installed locally in your project use dotnet tool update dotnet-ef. Install a specific version by appending --version <VERSION> to your command. See the Update section of the dotnet tool documentation for more details.

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

You can specify the environment for ASP.NET Core projects on the command-line. This and any additional arguments are passed into Program.CreateHostBuilder.

dotnet ef database update -- --environment Production

Tip

The -- token directs dotnet ef to treat everything that follows as an argument and not try to parse them as options. Any extra arguments not used by dotnet ef are forwarded to the app.

Common options

Option Short Description
--json Show JSON output.
--context <DBCONTEXT> -c 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.
--project <PROJECT> -p Relative path to the project folder of the target project. Default value is the current folder.
--startup-project <PROJECT> -s 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.
--no-build Don't build the project. Intended to be used when the build is up-to-date.
--help -h Show help information.
--verbose -v Show verbose output.
--no-color Don't colorize output.
--prefix-output Prefix output with level.

Any additional arguments are passed to the application.

dotnet ef database drop

Deletes the database.

Options:

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

The common options are listed above.

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.

Options:

Option Description
--connection <CONNECTION> The connection string to the database. Defaults to the one specified in AddDbContext or OnConfiguring.

The common options are listed above.

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

dotnet ef database update InitialCreate
dotnet ef database update 20180904195021_InitialCreate --connection your_connection_string

dotnet ef dbcontext info

Gets information about a DbContext type.

The common options are listed above.

dotnet ef dbcontext list

Lists available DbContext types.

The common options are listed above.

dotnet ef dbcontext optimize

Generates a compiled version of the model used by the DbContext.

See Compiled models for more information.

Options:

Option Short Description
--output-dir <PATH> -o The directory to put files in. Paths are relative to the project directory.
--namespace <NAMESPACE> -n The namespace to use for all generated classes. Defaults to generated from the root namespace and the output directory plus CompiledModels.

The common options are listed above.

The following example uses the default settings and works if there is only one DbContext in the project:

dotnet ef dbcontext optimize

The following example optimizes the model for the context with the specified name and places it in a separate folder and namespace:

dotnet ef dbcontext optimize -o Models -n BlogModels -c BlogContext

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 Short Description
--data-annotations -d Use attributes to configure the model (where possible). If this option is omitted, only the fluent API is used.
--context <NAME> -c 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.
--context-namespace <NAMESPACE> The namespace to use for the generated DbContext class. Note: overrides --namespace.
--force -f Overwrite existing files.
--output-dir <PATH> -o The directory to put entity class files in. Paths are relative to the project directory.
--namespace <NAMESPACE> -n The namespace to use for all generated classes. Defaults to generated from the root namespace and the output directory.
--schema <SCHEMA_NAME>... The schemas of tables and views to generate entity types for. To specify multiple schemas, repeat --schema for each one. If this option is omitted, all schemas are included. If this option is used, then all tables and views in the schemas will be included in the model, even if they are not explicitly included using --table.
--table <TABLE_NAME>... -t The tables and views to generate entity types for. To specify multiple tables, repeat -t or --table for each one. Tables or views in a specific schema can be included using the 'schema.table' or 'schema.view' format. If this option is omitted, all tables and views are included.
--use-database-names Use table, view, sequence, 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.
--no-onconfiguring Suppresses generation of the OnConfiguring method in the generated DbContext class.
--no-pluralize Don't use the pluralizer.

The common options are listed above.

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 and namespace:

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 --context-namespace New.Namespace

The following example reads the connection string from the project's configuration set using the Secret Manager tool.

dotnet user-secrets set ConnectionStrings:Blogging "Data Source=(localdb)\MSSQLLocalDB;Initial Catalog=Blogging"
dotnet ef dbcontext scaffold Name=ConnectionStrings:Blogging Microsoft.EntityFrameworkCore.SqlServer

The following example skips scaffolding an OnConfiguring method. This can be useful when you want to configure the DbContext outside of the class. For example, ASP.NET Core apps typically configure it in Startup.ConfigureServices.

dotnet ef dbcontext scaffold "Server=(localdb)\mssqllocaldb;Database=Blogging;User Id=myUsername;Password=myPassword;" Microsoft.EntityFrameworkCore.SqlServer --no-onconfiguring

dotnet ef dbcontext script

Generates a SQL script from the DbContext. Bypasses any migrations.

Options:

Option Short Description
--output <FILE> -o The file to write the result to.

The common options are listed above.

dotnet ef migrations add

Adds a new migration.

Arguments:

Argument Description
<NAME> The name of the migration.

Options:

Option Short Description
--output-dir <PATH> -o The directory use to output the files. Paths are relative to the target project directory. Defaults to "Migrations".
--namespace <NAMESPACE> -n The namespace to use for the generated classes. Defaults to generated from the output directory.

The common options are listed above.

dotnet ef migrations bundle

Creates an executable to update the database.

Options:

Option Short Description
--output <FILE> -o The path of executable file to create.
--force -f Overwrite existing files.
--self-contained Also bundle the .NET runtime so it doesn't need to be installed on the machine.
--target-runtime <RUNTIME_IDENTIFIER> -r The target runtime to bundle for.

The common options are listed above.

dotnet ef migrations has-pending-model-changes

Note

This command was added in EF Core 8.0.

Checks if any changes have been made to the model since the last migration.

Options:

The common options are listed above.

dotnet ef migrations list

Lists available migrations.

Options:

Option Description
--connection <CONNECTION> The connection string to the database. Defaults to the one specified in AddDbContext or OnConfiguring.
--no-connect Don't connect to the database.

The common options are listed above.

dotnet ef migrations remove

Removes the last migration, rolling back the code changes that were done for the latest migration.

Options:

Option Short Description
--force -f Revert the latest migration, rolling back both code and database changes that were done for the latest migration. Continues to roll back only the code changes if an error occurs while connecting to the database.

The common options are listed above.

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 Short Description
--output <FILE> -o The file to write the script to.
--idempotent -i Generate a script that can be used on a database at any migration.
--no-transactions Don't generate SQL transaction statements.

The common options are listed above.

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