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Problem with database first scaffolding

See original GitHub issue

I’m having problem with scaffolding DbContext. I’m using latest .NET Core 1.1.0 SDK. I’m following this guide: https://docs.microsoft.com/en-us/ef/core/get-started/aspnetcore/existing-db

But when I run following command in Package Manager Console: Scaffold-DbContext "<connection-string>" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models I get exception.

project.json

  "dependencies": {
    "Microsoft.EntityFrameworkCore": "1.1.0",
    "Microsoft.EntityFrameworkCore.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer": "1.1.0",
    "Microsoft.EntityFrameworkCore.SqlServer.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final",
    "NETStandard.Library": "1.6.1"
  },

  "tools": {
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final"
  },

  "frameworks": {
    "netstandard1.6": {
      "imports": [
        "dnxcore50"
      ]
    }
  }

Exception

System.IO.FileNotFoundException: Could not load file or assembly 
'System.Data.SqlClient, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. The system cannot find the file specified.
File name: 'System.Data.SqlClient, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.SqlServerDatabaseModelFactory.Create(String connectionString, TableSelectionSet tableSelectionSet)
   at Microsoft.EntityFrameworkCore.Scaffolding.RelationalScaffoldingModelFactory.Create(String connectionString, TableSelectionSet tableSelectionSet)
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.SqlServerScaffoldingModelFactory.Create(String connectionString, TableSelectionSet tableSelectionSet)
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.ReverseEngineeringGenerator.GetMetadataModel(ReverseEngineeringConfiguration configuration)
   at Microsoft.EntityFrameworkCore.Scaffolding.Internal.ReverseEngineeringGenerator.GenerateAsync(ReverseEngineeringConfiguration configuration, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Design.Internal.DatabaseOperations.ScaffoldContextAsync(String provider, String connectionString, String outputDir, String dbContextClassName, IEnumerable`1 schemas, IEnumerable`1 tables, Boolean useDataAnnotations, Boolean overwriteFiles, CancellationToken cancellationToken)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.<ScaffoldContextImpl>d__22.MoveNext()
   at System.Collections.Generic.EnumerableHelpers.ToArray[T](IEnumerable`1 source, Int32& length)
   at System.Collections.Generic.EnumerableHelpers.ToArray[T](IEnumerable`1 source)
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.<>c__DisplayClass4_0`1.<Execute>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
Could not load file or assembly 'System.Data.SqlClient, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. The system cannot find the file specified.

Issue Analytics

State:
Created 7 years ago
Comments:9 (4 by maintainers)

Top GitHub Comments

2reactions

Xamarianscommented, May 11, 2017

I were having the same error. Fixed by making it default project (“Set as Startup Project”).

1reaction

LoopsLucommented, Feb 8, 2017

I use this project.json. I think it is enough. I copied some settings from the WebApi project, and it works as well as the WebApi project in my Library project.

{ “dependencies”: { “Microsoft.NETCore.App”: { “version”: “1.0.1”, “type”: “platform” }, “Microsoft.EntityFrameworkCore”: “1.1.0”, “Microsoft.EntityFrameworkCore.SqlServer”: “1.1.0”, “Microsoft.EntityFrameworkCore.SqlServer.Design”: “1.1.0”, “Microsoft.EntityFrameworkCore.Tools”: “1.1.0-preview4-final”, “NETStandard.Library”: “1.6.1” },

“frameworks”: { “netcoreapp1.0”: { “imports”: [ “dotnet5.6”, “portable-net45+win8” ] } } }

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