Re: Subtracting dates, any help is welcome

Hi,

"J. van der Laan" <jan_at_nl.uu.net> writes:
>
> Surely this is pretty simple....but how simple it is I do not know.
>
> I want to subtract two dates from eachother and want the output to be in
> hours/minutes/seconds.
>
> The only thing I did achieve until now is;
> SQL statement;
> # select sum(out_time-in_time) from database where field=value;
>
> Output;
> SUM(OUT_TIME-IN_TIME)
> ---------------------
> .053784722
>
> What does this output value say/mean???
> btw; The OUT_TIME and IN_TIME fields are of type DATE.
>

Oracle returns the difference between two DATE variables or fields in days. The fractional part constitutes the hours, minutes and seconds. So, SUM(OUT_TIME-IN_TIME)*24 would be the difference in hours (with the fractional part constitutin the minutes and seconds).

Hope this helps.

-- 
Karel Sprenger <ks_at_ic.uva.nl>               | phone: +31-20-525 2302
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