可能会遇到的问题:
Both Entity Framework 6.x and Entity Framework Core commands are installed. The Entity Framework 6 version is executing. You can fully qualify the command to select which one to execute, 'EntityFrameworkUpdate-Database' for EF6.x and 'EntityFrameworkCoreUpdate-Database' for EF Core.
解决方法:
EntityFrameworkCoreAdd-Migration InitialDb
EntityFrameworkCoreUpdate-Database