my $select1 = "select distinct b.carrier, b.boxno, b.listno, b.shipno, b.custno
from data1 b
where b.custno = 160
order by b.listno ";

my $sth = $dbhandle1->prepare($select1);
$sth->execute();
print "carrier,boxno,listno,shipno,custno\n";
while (my  $hash_ref = $sth->fetchrow_hashref) {
   print "$hash_ref->{carrier},";
   print "$hash_ref->{boxno},";
   print "$hash_ref->{listno},";
   print "$hash_ref->{shipno},";
   print "$hash_ref->{custno}\n";
}