I am trying to create a simple table using Umbraco's database migration system, and I can't figure out how to create a table with a composite primary key.

Here's an example of the code I am trying to use:

using Umbraco.Core.Migrations;
using Umbraco.Core.Persistence.DatabaseModelDefinitions;
using DbConstants = MyProjects.Data.Constants.Database;

namespace MyProjects.Data.Migrations
{
  public class _00_Create : MigrationBase
  {
    public _00_Create( IMigrationContext context ) : base( context ) { }

    public override void Migrate()
    {
      if ( !TableExists( DbConstants.TBL_NAME ) ) {
        Create.Table( DbConstants.TBL_NAME )
          .WithColumn( "Composite1" )
            .AsString( 40 )
            .NotNullable()
            .PrimaryKey( "PK_Composite1" )
          .WithColumn( "Composite2" )
            .AsString( 40 )
            .NotNullable()
            .PrimaryKey("PK_Composite2")
          .WithColumn( "DateAdded" )
            .AsDateTime()
            .WithDefault( SystemMethods.CurrentDateTime )
          .WithColumn( "DateUpdated" )
            .AsDateTime()
            .WithDefault( SystemMethods.CurrentDateTime )
          .Do();
      }
    }
  }
}

The above is only an example of what I'm trying to do, hence the rubbish column naming.

I am aware that there's a way to pass a type into the Create.Table method instead, but I have read that it's inadvisable to use that method with migrations.

Is someone able to explain how to create such a table using Umbraco Migrations?

Thanks