That's a start, but try breaking it down even further into a command line script that only uses DBI and HTML::Template:

use strict;
use warnings;

use HTML::Template;
use DBI;

my $id = shift || 42;

my $dbh  = DBI->connect( ... );
my $tmpl = HTML::Template->new(filehandle => \*DATA);

my $product = $dbh->selectall_arrayref(q{
    SELECT image, price, description, serial
    FROM product
    WHERE id = ?
}, {Slice => {}}, $id);

# i think it's better to use a variable instead of
# passing the results from the query directly to the
# $tmpl->param method (easier debugging)
 
$tmpl->param(product => $product);

print $tmpl->output;


__DATA__
<tmpl_loop product> 
      image: <tmpl_var image>
      price: <tmpl_var price>
description: <tmpl_var description>
     serial: <tmpl_var serial>
</tmpl_loop>
[download]

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)