DATEDIFF(t,s) 
DATEDIFF(t,s) is a date function that calculates the number of days between a start and end date.
t and s values: When used in a function, the expressions t and s (date_or_timestamp_expression) must supply a date, a time stamp, or an alphanumeric value that matches the current date or time stamp format.
t, s |
Result of DATEDIFF(t,s) Function |
|---|---|
Positive difference between t and s |
Numeric value (number of days) |
t or s are time stamp values |
Only the dates in the time stamp value are used to calculate DATEDIFF(t,s). |
t or s is a NULL value |
NULL value |
Example
SELECT arrival, departure, DATEDIFF(departure,arrival) difference, rno
FROM reservation
WHERE rno = 130
ARRIVAL |
DEPARTURE |
DIFFERENCE |
RNO |
2005-02-01 |
2005-02-03 |
2 |
130 |
End of the example.