My code:
$sth = $dbh->prepare('insert into mytable(id, start_date, end_date, reason)
values(?,?,add_date(?,interval ? day),?)') || die $dbh->errstr;

Error:
DBD::mysql::st execute failed: parse error near '('2001.03.11',interval 7 day),66-98)' at line 2 at myscript.pl line 111.

Why?!

Regards.