SQL DATE_SUB() function subtracts a specified time interval from a date.

Table – orders

+—–+—–+——-+———————+
| oid | uid | items | date                |
+—–+—–+——-+———————+
|   1 |   1 | AAAA  | 2007-05-16 00:00:00 |
+—–+—–+——-+———————+

Example

mysql> SELECT DATE_SUB(date, INTERVAL 4 DAY) FROM orders;
+——————————–+
| DATE_SUB(date, INTERVAL 4 DAY) |
+——————————–+
| 20007-05-12 00:00:00            |
+——————————–+
1 row in set (0.00 sec)

Unit

MICROSECOND
SECOND
MINUTE
HOUR
DAY
WEEK
MONTH
QUARTER
YEAR
SECOND_MICROSECOND
MINUTE_MICROSECOND
MINUTE_SECOND
HOUR_MICROSECOND
HOUR_SECOND
HOUR_MINUTE
DAY_MICROSECOND
DAY_SECOND
DAY_MINUTE
DAY_HOUR