in reply to On Handling Text (Blob) Column Types in MySQL/CGI

That INSERT query looks wacky. Try
my $sth = $dbh->prepare("INSERT INTO t2d (textfield, node_id) VALUES +(?, ?)");
or, if you really are updating an existing record, try
my $sth = $dbh->prepare("UPDATE t2d SET textfield=? WHERE node_id=?" +);