When two dates are subtracted or added, the value returned is the number of days, possibly with a fractional day.

How many days until the end of the month?

select last_day(sysdate) – sysdate from dual;

How many days until next Monday?

select next_day(sysdate,’Monday’) – sysdate from dual;

How many days until 12:00 on the 12/31/2006?

select trunc(to_date(’12/31/2006 12:00:00′) – sysdate) from dual;

To do this with dates stored as characters, use the to_date function as in the last example.

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