Well, if you want to check whether $row->[0]
and $row->[1] exists without autovivification,
just check whether $row contains any elements.
$row->[0] can only exist if and only if
@$row > 0. Similar, $row -> [1]
only exists if and only if @$row > 1.
Note that from 5.6.0 onwards, delete and
exists work on arrays as well.