Additional Where Clauses: WhereColumn

$users = DB::table('users')
                ->whereColumn('first_name', 'last_name')
                ->get();

$users = DB::table('users')
                ->whereColumn('updated_at', '>', 'created_at')
                ->get();

$users = DB::table('users')
                ->whereColumn([
                    ['first_name', '=', 'last_name'],
                    ['updated_at', '>', 'created_at']
                ])->get();