Average difference in days between dates from two datetime columns?

Asked Mar 05 '14 at 17:23

Active Mar 05 '14 at 17:23

Viewed 1,100 times

I've seen a few of these types of questions on stackoverflow, but they don't quite fit in with my question:

Is this a valid query to see the average difference in days between two dates from two datetime columns?

SELECT AVG(DATEDIFF(DATE(datetime_column1),DATE(datetime_column2)))
FROM table_name
WHERE status = 2

Further, I am wanting to group by another column, e.g.

SELECT AVG(DATEDIFF(DATE(datetime_column1),DATE(datetime_column2))),grouping_column
FROM table_name
WHERE status = 2
GROUP BY grouping_column

asked Mar 05 '14 at 17:23

Drewdavid

There might be some "off-by-one" issues. If the two dates are on the same day, is that "0" or "1" days? – Gordon Linoff Mar 05 '14 at 17:26
1

You can drop the `DATE()` functions, since `DATEDIFF()` only uses the date portion anyway. – Marcus Adams Mar 05 '14 at 17:35
Why are you asking if this is valid? Can't you run it? Did return values you didn't like? – AgRizzo Mar 05 '14 at 17:45

0 Answers0