Time function of Oracle single-line function

Select Systemdate from dual--get time

Select systemdate+300 from dual--date + number = date, which represents a date after several days

Select systemdate-300 from dual--date + number = date, representing the date of the previous several days

Select Last_day (date) from dual--select last_day (systemdate) from dual find the last day of the month

Select Next_day (systemdate, ' Monday ') from dual--get the last Sunday of the month

Select Add months (systemdate,4) from dual--find out the date after a few months

Time function of Oracle single-line function