When trying to scaffold with asp.net core this command
scaffold-dbcontext "Data Source=(local);Initial
Catalog=MyDb;Integrated Security=True;"
Microsoft.EntityFrameworkCore.sqlserver -outputdir Models
Gives this error.
scaffold-dbcontext : The term 'scaffold-dbcontext' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again. At line:1 char:1 + scaffold-dbcontext "Data Source=(local);Initial Catalog=MyDB;In ... + ~~~~~~~~~~~~~~~~~~ + CategoryInfo : ObjectNotFound: (scaffold-dbcontext:String) [], CommandNotFoundException + FullyQualifiedErrorId : CommandNotFoundException
I have tried the solution here, but it does not work for me.
Any idea what the cause/cure could be?
For me apparently it worked once I have also ran in Package Manager console :
Install-Package Microsoft.EntityFrameworkCore.Tools
Also make sure :
To have other dependencies (for example Microsoft.EntityFrameworkCore, Microsoft.EntityFrameworkCore.SqlServer, Microsoft.EntityFrameworkCore.SqlServer.Design...) referenced depending of your needs.
To select the right assembly as target for your commands in the top-right corner of the PM console (I am frequently fooled by forgetting it...)
Another problem I encountered : with the dbcontext located in a separate class library, I was encountering the following error :
Unable to find provider assembly with name Microsoft.EntityFrameworkCore.SqlServer. Ensure the specified name is correct and is referenced by the project.
Which I was able to fix by setting my class library as Startup project in VS (don't ask why as it seems meaningless, but it worked).
Late edit, there's something else to know : You can't run Scaffold-DbContext against a class library targetting only .Net Standard, you must also enable netcoreapp in it, or Scaffold-DbContext will complain. To support both targets, edit the csproj to put : <TargetFrameworks>netcoreapp2.2;netstandard2.0</TargetFrameworks>
Instead of <TargetFramework>
section.
After all these you'll be able to run your Scaffold-DbContext
command line with proper arguments and connection string.
-- 2022 update --
I'm glad to see that post is still helpful as it receives some new upvotes, but instead of command-line scaffolding, there's a newer solution for the happy users of VS : you can rely on the retro-engineering feature of the extension EF Core Power tools.
I'm using it in all my new projects since a while and I find it much more powerful than raw command line, and it allows you to save your execution settings (which will avoid you to create a .bat with your custom command line). Of course, it's your choice.
Had the same problem. In my case i was missing some dependencies, so make sure that you have the following one :
Microsoft.EntityFrameworkCore
Microsoft.EntityFrameworkCore.SqlServer
Microsoft.EntityFrameworkCore.Tools
https://i.stack.imgur.com/Lbqgp.png
Hope this would help. :)
Make sure that this is available in your project.json file "Microsoft.EntityFrameworkCore.Tools.DotNet": "1.0.0-preview3-final".
https://i.stack.imgur.com/Hqq5X.png
Run the command in the package manager console
https://i.stack.imgur.com/zLEHq.png
that's all it will work
Make sure you run VS as Administrator and have installed the following packages:
Microsoft.EntityFrameworkCore.SqlServer
Microsoft.EntityFrameworkCore.SqlServer.Design
Microsoft.EntityFrameworkCore.Tools
Scaffold
command is part of dbcontext
command in EF. Below are the details for successful scaffold
:
https://i.stack.imgur.com/0MWgB.png
Package references required:
<PackageReference Include="Microsoft.EntityFrameworkCore" Version="3.0.0"/>
<PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="3.0.0"/>
<PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="3.0.0"/>
<PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="3.0.0"/>
So our scaffold command should look like:
dotnet ef dbcontext scaffold "Server=localhost\SQLEXPRESS;Database=MyDatabase;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -o OutputDirectory
Your Server
value might differ as per your Db server name. Replace MyDatabase
with your Database name like master
and OutputDirectory
to the location you want your newly created scaffolded classes like Models
folder.
Make sure you are using the right console, the "Package Manager Console". There is also a "Terminal" console which looks very similar, but doesn't work for this command. Package Manager Console can be found in View -> Other Windows (as of Visual Studio 2019, ver. 16.6.5)
I had installed Microsoft.EntityFrameworkCore.Tools
from NuGet Package Manager
and it was visible in the installed packages. But I kept getting this error.
Restarting Visual Studio (2019/Version 16.4.4) fixed it for me.
For me this error was caused by extra spacing was added around the hyphens, which was for some reason added when copy pasting from the command from the docs. Removing the spacing fixed it.
causes error:
Scaffold - DbContext "Server=(localdb)\mssqllocaldb;Database=myDbName;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer - OutputDir Models
the fix:
Scaffold-DbContext "Server=(localdb)\mssqllocaldb;Database=myDbName;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models
The docs also say if you receive this error, try restarting Visual Studio.
https://docs.microsoft.com/en-us/ef/core/get-started/aspnetcore/existing-db
If you're using .NetCore 2.2
then the command
below works like a charm for me either in Command Prompt (CMD)
or on Git Bash
.
Make sure that you are directly on the project folder before running the command
.
For example C:\App\ProjectName:
dotnet ef dbcontext scaffold "Server=.\;Database=Databasename;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -o Model
With VS2022, none of them worked.
But I installed EF
dotnet tool install --global dotnet-ef
and changed the code;
dotnet ef dbcontext scaffold "Server=servername;Database=dbname;Persist Security Info=True;User ID=XXX;Password=YYY;" Microsoft.EntityFrameworkCore.SqlServer -o Models
Also I had to install .Net 6.0 hosting bundle https://dotnet.microsoft.com/en-us/download/dotnet/6.0/runtime?cid=getdotnetcore
I ran into another cause of this error recently: NuGet
itself was out of date.
Updating NuGet
resolved the issue.
If Devanathan's answer doesn't work for you, check to make sure NuGet
itself is up to date.
If your solution has more than one project and the EF files are not in the startup project, make sure you choose the correct project here
https://i.stack.imgur.com/OO08d.png
Success story sharing