To "unapply" the most (recent?) migration after it has already been applied to the database:
- Open the SQL Server Object Explorer (View -> "SQL Server Object Explorer")
- Navigate to the database that is linked to your project by expanding the small triangles to the side.
- Expand "Tables"
- Find the table named "dbo._EFMigrationsHistory".
- Right click on it and select "View Data" to see the table entries in Visual Studio.
- Delete the row corresponding to your migration that you want to unapply (Say "yes" to the warning, if prompted).
- Run "dotnet ef migrations remove" again in the command window in the directory that has the project.json file. Alternatively, run "Remove-Migration" command in the package manager console.
Hope this helps and is applicable to any migration in the project... I tested this out only to the most recent migration...
Happy coding!