The ADD_MONTHS function returns the date that is n months after the specified date.
A DATETIME expression that identifies the starting date. When the day component of start_datetime is the last day of the month or when the returned month has fewer days, then the returned day component is the last day of the month. Otherwise, the day component of the returned date is the same as the day component of start_datetime. See Example 8-19, "End-of-Month Calculation".
An INTEGER that identifies the number of months to be added to start_datetime.
Example 8-19 End-of-Month Calculation
The following statement displays the date of the day that is one month after January 30, 2000.
SHOW ADD_MONTHS('30Jan00', 1)
Since February 29 was the last day of February 2000, ADD_MONTHS returns February 29, 2000.