You can convert dates to characters using the TO_DATE() function as shown in the following examples:

SELECT TO_DATE('07-MAY-2006', 'DD-MON-YYYY') FROM DUAL;

07-MAY-06

SELECT TO_DATE('2006/05/07 ', 'YYYY/MM/DD') FROM DUAL;

07-MAY-06

SELECT TO_DATE('MAY 07, 2006', 'MONTH DD, YYYY')

FROM DUAL;

07-MAY-06

SELECT TO_DATE('May 7, 2006', 'fmMONTH DD, YYYY') FROM DUAL;

07-MAY-06

SELECT TO_DATE('SUNDAY, MAY 7, 2006',

'fmDAY, MONTH DD, YYYY') FROM DUAL;

07-MAY-06