my $ht = new HTML::Template(filename=>'main.tmpl');
my $db_data=print();
$ht->params(db_data=>$db_data,%stuff);
print $ht->output;

sub print()
{
  my $ht = new HTML::Template(filename=>'database_info.tmpl');
  @foo=$dbh->do("select * from *"); # ok so it's not even vaugely legal. do yer own db code
  $ht->params(dbstuff=>@foo);
  return $ht->output; #probably not optimal
}