next_day [Oracle SQL]

next_day(date,'some-weekday')

some-weekday is one of monday, tuesday, ..... sunday (if the session's language is english).

Example: what's the next tuesday after May 20^th 2007?

select next_day(date '2007-05-20', 'TUE') from dual;

22-MAY-07

See also add_months, last_day, months_between.