Syntax
ADDDATE(date,INTERVAL expr unit)
ADDDATE(expr,days)
Purpose
When the first syntax is used, ADDDATE() is a synonym of the DATE_ADD() function. For more information about the unit argument, see DATE_ADD.
When the second syntax is used, this function adds the specified days to the specified date expr.
Examples
obclient> SELECT ADDDATE('2021-08-01', INTERVAL 31 DAY);
+----------------------------------------+
| ADDDATE('2021-08-01', INTERVAL 31 DAY) |
+----------------------------------------+
| 2021-09-01 |
+----------------------------------------+
1 row in set
obclient> SELECT ADDDATE('2021-08-01', 31);
+---------------------------+
| ADDDATE('2021-08-01', 31) |
+---------------------------+
| 2021-09-01 |
+---------------------------+
1 row in set