ASP.NET Core EF Add-Migration command not working

Question

Following this Microsoft Tutorial when I run the PM> Add-Migration MyFirstMigration command in VS2015 project created from the same tutorial I get the following error that I can't resolve:

More than one DbContext was found. Specify which one to use.
Use the '-Context' parameter for PowerShell commands and the '--context' parameter for dotnet commands.

Point to note

1. I'm using the above tutorial with the exception that I'm using Individual User Account authentication instead of No Authentication used in the tutorial.
2. I've latest release of ASP.NeT Core 1.0 and VS2015-Update 3 on windows 8.1
3. This is a freshly created project. No other DbContext was manually installed

Answer 1

Running the following command (obtained from this article ) and a response from @Maverik (from StackOverflow here ) and a suggestion from @doctor above helped me resolved the issue. Thank you all for your help:

PM> Add-Migration MyFirstMigration -Context BloggingContext

Answer 2

The error clearly explains to mention --context with db Context name if more than one DbContext. So try by mentioning your DbContext name.

dotnet ef migrations add Initial --context SampleDbContext

Hope this helps.

Answer 3

If you need only update a identity schema existent, try it:

update-database -Context ApplicationDbContext

ApplicationDbContext = your identity context

Answer 4

that because you have two DbContext in your solution. First is default created when you creating project(ApplicationDbContext) and second your EF DbContext. Solution is described in error message just specify your EF DbContext

Answer 5

Add-Migration MyFirstMigration -Context DbContextName

它在我的项目中有效。

Answer 6

Use below to commands:

PM> Add-Migration MyFirstMigration -Context YourDbContext

PM> update-database -Context YourDbContext

Answer 7

Following this Microsoft Tutorial when I run the PM> Add-Migration MyFirstMigration command in VS2015 project created from the same tutorial I get the following error that I can't resolve:

More than one DbContext was found. Specify which one to use.
Use the '-Context' parameter for PowerShell commands and the '--context' parameter for dotnet commands.

Point to note

1. I'm using the above tutorial with the exception that I'm using Individual User Account authentication instead of No Authentication used in the tutorial.
2. I've latest release of ASP.NeT Core 1.0 and VS2015-Update 3 on windows 8.1
3. This is a freshly created project. No other DbContext was manually installed

Answer 8

[--context]

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.

Add-Migration MyMigration -context DataContextName