package PriceType;
use base qw(Class::Singleton);

sub id { croak "this should return the price_type_id" };

my $dbh = DBI->connect(...);
my $price_type = $dbh->prepare('select price_type_id, price_type_label from price_type');
$price_type->execute;
$price_type->bind_columns(my \($id, $label) );
while (my $type = $price_type->fetch) {
    $label =~ = s/[^a-z]//gs;
    my $method = join('::', __PACKAGE__, $label, "id");
    my $id = $id;
    { no strict 'refs'; *{$method} = sub { $id } };
};