my $sql = <<'__END__';
SELECT n.id
  FROM nodes n, meta_data md
 WHERE md.name = ?
   AND md.value = ?
   AND n.id = md.node_id
 ORDER BY 1
__END__

my $sth = $dbh->prepare_cached($sql) || die $!;
$sth->execute($attr, $value) || die $!;
# Use your favorite fetch*() method here
$sth->finish;