my $prefix = $yaml->{$branchcode} || '666';

$query = "SELECT MAX(CAST(SUBSTRING(barcode,-4) AS signed)) from items where barcode REGEXP ?";
$sth=C4::Context->dbh->prepare($query);
$sth->execute("^$prefix$args->{year}$args->{mon}");

while (my ($count)= $sth->fetchrow_array) {
    warn "Examining Record: $count" if $DEBUG;
    $nextnum = $count if $count;
}

$nextnum++;
$nextnum = sprintf("%0*d", "5",$nextnum);

$barcode = $prefix;
$barcode .= $args->{year}.$args->{mon}.$nextnum;