Date format help

Hello,

I can't get any luck in setting up a non-default date format. After submitting a statement

SQL> alter session set nls_date_format = 'MM-DD-YYYY';

NLS_DATE_FORMAT parameter has changed to a new format. BUT browsing the actual data with the SELECT statement truncates it up to 9 characters.
Can someone told where I am wrong?

Best regards,
Jane Received on Wed Jun 11 1997 - 00:00:00 CDT