my $sql = "SELECT script FROM scripts where name=?";
my $sth = $dbh->prepare($sql);
$sth->execute($ref->{name});

##</code><code>##

"$sql"                 ->  $sql
"$row_hash->{script}"  ->  $row_hash->{script}
"$script"              ->  $script

##</code><code>##

$r->puts(<<"END");     \
$post                   >  $->puts($post)
END                    /

##</code><code>##

my $row_hash = $sth->fetchrow_hashref()
   or die(...);

$script = $row_hash->{script};          

##</code><code>##

my $result = eval $script;
defined($result)
   or die(...);

$post .= $result;