title: Entity Framework Core Missing Argument 'PROVIDER'
body: <p>I am trying to connect my ASP.NET Core website to a database using a migration. I am using the command</p>
  <pre><code>Scaffold-DbContext &quot;Data Source=localhost;Initial Catalog=BlogDB;Integrated Security=True&quot; Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models
  </code></pre>
  <p>To generate the models etc. However I get the following error on running the command:</p>
  <blockquote>
  <p>Missing required argument ''</p>
  </blockquote>
  <p>If required the startup class is just the standard template currently:</p>
  <pre><code>using Microsoft.AspNetCore.Builder;
  using Microsoft.AspNetCore.Hosting;
  using Microsoft.Extensions.Configuration;
  using Microsoft.Extensions.DependencyInjection;
  using Microsoft.Extensions.Hosting;
  
  namespace Personal_Blog
  {
      public class Startup
      {
          public Startup(IConfiguration configuration)
          {
              Configuration = configuration;
          }
  
          public IConfiguration Configuration { get; }
  
          // This method gets called by the runtime. Use this method to add services to the container.
          public void ConfigureServices(IServiceCollection services)
          {
              services.AddControllersWithViews();
  
          }
  
          // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
          public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
          {
              if (env.IsDevelopment())
              {
                  app.UseDeveloperExceptionPage();
              }
              else
              {
                  app.UseExceptionHandler(&quot;/Home/Error&quot;);
                  // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                  app.UseHsts();
              }
              app.UseHttpsRedirection();
              app.UseStaticFiles();
  
              app.UseRouting();
  
              app.UseAuthorization();
  
              app.UseEndpoints(endpoints =&gt;
              {
                  endpoints.MapControllerRoute(
                      name: &quot;default&quot;,
                      pattern: &quot;{controller=Home}/{action=Index}/{id?}&quot;);
              });
          }
      }
  }
  
  </code></pre>
  <p>An example of the problem is:</p>
  <pre><code>PM&gt; Scaffold-DbContext &quot;Data Source=localhost;Initial Catalog=BlogDB;Integrated Security=True&quot; Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models -Verbose
  Using project 'Personal Blog'.
  Using startup project 'Personal Blog'.
  Build started...
  Build succeeded.
  C:\Program Files\dotnet\dotnet.exe exec --depsfile &quot;D:\Code\Personal\Personal Blog\Personal Blog\Personal Blog\bin\Debug\netcoreapp3.1\Personal Blog.deps.json&quot; --additionalprobingpath C:\Users\samh\.nuget\packages --additionalprobingpath &quot;C:\Program Files\dotnet\sdk\NuGetFallbackFolder&quot; --runtimeconfig &quot;D:\Code\Personal\Personal Blog\Personal Blog\Personal Blog\bin\Debug\netcoreapp3.1\Personal Blog.runtimeconfig.json&quot; C:\Users\samh\.nuget\packages\microsoft.entityframeworkcore.tools\6.0.0-preview.1.21102.2\tools\netcoreapp2.0\any\ef.dll dbcontext scaffold &quot;Data Source=localhost;Initial Catalog=BlogDB;Integrated Security=True&quot; Microsoft.EntityFrameworkCore.SqlServer --json --output-dir Models --verbose --no-color --prefix-output --assembly &quot;D:\Code\Personal\Personal Blog\Personal Blog\Personal Blog\bin\Debug\netcoreapp3.1\Personal Blog.dll&quot; --startup-assembly &quot;D:\Code\Personal\Personal Blog\Personal Blog\Personal Blog\bin\Debug\netcoreapp3.1\Personal Blog.dll&quot; --project-dir &quot;D:\Code\Personal\Personal Blog\Personal Blog\Personal Blog\\&quot; --language C# --working-dir &quot;D:\Code\Personal\Personal Blog\Personal Blog&quot; --root-namespace Personal_Blog
  Microsoft.EntityFrameworkCore.Tools.CommandException: Missing required argument '&lt;PROVIDER&gt;'.
     at Microsoft.EntityFrameworkCore.Tools.Commands.DbContextScaffoldCommand.Validate()
     at Microsoft.EntityFrameworkCore.Tools.Commands.CommandBase.&lt;&gt;c__DisplayClass0_0.&lt;Configure&gt;b__0(String[] args)
     at Microsoft.DotNet.Cli.CommandLine.CommandLineApplication.Execute(String[] args)
     at Microsoft.EntityFrameworkCore.Tools.Program.Main(String[] args)
  Missing required argument '&lt;PROVIDER&gt;'.
  </code></pre>
  <p>Could anyone advise as to what I am missing?</p>
  <p>Many thanks in advance.</p>