Because the iterator ->fetchrow_hashref returns one scalar undef when done

Usually I use fetchrow_array - I don't think I have used fetchrow_hashref before.

The problem came because I was converting from this code

    my @frames;
    my $query = $dbh->prepare("SELECT idFrame, name, colour FROM Frame
+");
    $query->execute();
    while (my ($id, $name, $colour) = $query->fetchrow_array) {
        my $frame = {
            'image'  => 'test_thumb.jpg',
            'id'     => $id,
            'name'     => $name,
            'colour' => $colour,
        };
        push @frames, $frame;
    }
    my $vars = {
        'frames' => \@frames,
    };
    $template->process("admin_frames.tt", $vars);
[download]

    my @frames;
    my $query = $dbh->prepare("SELECT idFrame, name, colour FROM Frame
+");
    $query->execute();
    while (my ($frame) = $query->fetchrow_hashref) {
        $$frame{'image'} = 'test_thumb.jpg';
        push @frames, $frame;
    }
    my $vars = {
        'frames' => \@frames,
    };
    $template->process("admin_frames.tt", $vars);
[download]

I suspect that there is a more elegant solution that doesn't involve iterating through the rows from the database using fetchall_hashref but that's (possibly) for another day. There will only ever be a handful of rows returned by this query.