title: to_date function AM PM Format
body: <p>Reading from a csv file using perl and inserting into a oracle table.  In a particular csv field the date can be either in AM or PM format. So when i construct  the to_date I am using AM / PM but it's giving me format code error.    What formatcode needs to be provided in to_date to accept AM/PM Fields.</p>
  
  <pre><code>insert into invoices(invoice_id,invoice_date) values (2,to_date('2010-Aug-09 12:00:01 PM' , 'yyyy-Mon-dd HH:MI:SS AM / PM'));
  </code></pre>