Date Time Functions MySQL Tutorial

mysql>
mysql> select DATE_SUB(curdate(), INTERVAL 1 MICROSECOND);
+---------------------------------------------+
| DATE_SUB(curdate(), INTERVAL 1 MICROSECOND) |
+---------------------------------------------+
| 2007-07-21 23:59:59.999999                  |
+---------------------------------------------+
1 row in set (0.00 sec)