mysql>
mysql> SELECT DATE_FORMAT(DATE_SUB(CURDATE(), INTERVAL 6 MONTH), '%W the %D of %M %Y')
-> AS 'Six Months Ago';
+---------------------------------+
| Six Months Ago |
+---------------------------------+
| Sunday the 21st of January 2007 |
+---------------------------------+
1 row in set (0.00 sec)
mysql>