How is the last_day function used in Oracle?

The LAST_DAY function in Oracle database is used to return the last day of the month for a specified date. The syntax is as follows:

LAST_DAY(date)

In this case, date is either a date or a valid date expression.

For example, if today is October 15, 2022, then LAST_DAY(‘2022-10-15’) will return the last day of October 2022, which is October 31, 2022.