my $dbh = DBI->connect($DNS, {RaiseError=>1});
my $sth = $dbh->prepare(qq{SELECT product, price, quantity 
FROM products 
WHERE quantity < ? });		

$sth->execute(100);
sub ask_customer {
	# display product details
	# ask customer input 
	# do something smart with customer answer
}

while (my ($product, $price, $quantity) = $sth->fetchrow_array()) {
	ask_customer ($product, $price, $quantity);
}
$dbh->disconnect();