Select Code to Download

my $dbh = DBI->connect($DNS, {RaiseError=>1});
my $sth = $dbh->prepare(qq{SELECT product, price, quantity 
...
    ask_customer ($product, $price, $quantity);
}
$dbh->disconnect();

+----------------------+   +-----------------------+
|       customer       |   |          order        |
...
| P03 | 5.50  | pliers |
| P04 | 4.00  | cutter |
+-----+-------+--------+

my @customers = (
    [ 'C01', 'Joe',   'NY' ],
...
   [ 'C01', 'P04',   4 ],
   [ 'C01', 'P03',   1 ]
 );

SELECT cust.name AS customer, prod.name AS product,
price, qty, qty*price AS total
...
| Sue      | 28.20 |
| Joe      | 25.50 |
+----------+-------+

my %orders_by_customer = (
'Frank' => [ { product => 'pliers',  qty =>   9 },
...
             { product => 'pliers',  qty =>   1 }
           ] 
);

my %orders_by_customer = ();
while (my $href = $sth->fetchrow_hashref()) {
...
   );
   push @{$orders_by_customer{$href->{'customer'}}}, \%order;
}

 
    my $surname = 'Jones';
    my $query= 
        qq{SELECT name, surname FROM employees WHERE surname = $surnam
+e };
    my $sth = $dbh->prepare($query);
    $sth->execute();

 
    my $query= qq{SELECT name, surname FROM employees WHERE surname = 
+? };
    my $sth = $dbh->prepare($query);
    $sth->execute('Jones');