Spark SQL common date functions

• current_date()  The current date

select current_date();
--2022-02-22

• now() or current_timestamp() current time

select now();
select current_timestamp();
--2022-02-22 22:22:22

• datediff(endDate, startDate)    The number of days between the dates

select datediff('2022-02-22','2022-02-20');
--2

• months_between(endDate, startDate)  Month difference between dates

select months_between('2022-06-16','2022-02-12');
--4.12903226

• date_add(startDate, numDays)    Date plus N God

select date_add('2022-02-22',3)
--2022-02-25

select date_add('2022-02-22',-3)
--2022-02-19

• date_sub(startDate, numDays)    Date minus N God

select date_sub('2022-02-22',3)
--2022-02-19

select date_sub('2022-02-22',-3)
--2022-02-25

• add_months(startDate, numMonths)  Date plus N month

select add_months('2022-02-22',3);
--2022-05-22

select add_months('2022-02-22',-3);
--2021-11-22

• last_day(date)  The last day of the month in which the date is

select last_day('2022-02-22');
--2022-02-28

• next_day(startDate, dayOfWeek)  The first day of the week after the specified date （ Week parameter is English abbreviation ）

select next_day('2022-02-22','MON')
--2022-02-28

• other