I\'m using Entity Framework 5.0 with Code First migrations enabled.
I\'ve added Unique key by using:
CreateIndex(\"dbo.Groups\", \"Name\", true);
There is another answer to this:
DropIndex("dbo.Groups", new[]{"Name"});
There is an overload of DropIndex that takes column names, but it takes an array of them. So for a single column name you still have to wrap it in an array to get to the overload.