while (my $row = $sth->fetch()) {
    # Must copy since fetch reuses array.
    $row = [ @$row ];

    $q->enqueue(share($row));
}

##</code><code>##

my @queue;

# Put stuff in
while (...) {
    push @queue, ...;
}

# Take stuff out
while (@queue) {
    my $item = shift(@queue);
    ...
}