Problem with datetime

Hi,
I have a table on pGSQL 6.5.2 wich contains several accounting data
from radiusd in the following form:

bwin int8
bwout int8
name varchar()
start datetime
stop datetime
callerid varchar()
fr_protocol int4
fr_addr inet
data_rate int4
disconn_cause int4

I'm now trying to get summaries of the data in several time intervals
eg:

SELECT sum(stop-start) FROM logs WHERE name = 'intern-mw' and
start >= '28-10-1999' AND stop < ('28-10-1999'::datetime + '1 day'::timespan);
sum
-------------------------
@ 2 hours 57 mins 56 secs
(1 row)

Thats ok

The same for the 10-27-1999:

SELECT sum(stop-start) FROM logs WHERE name = 'intern-mw' and
start >= '27-10-1999' AND stop < ('27-10-1999'::datetime + '1 day'::timespan);
sum
-------------------------
@ 4 hours 37 mins 20 secs
(1 row)

I think, thats also ok.

But now both days at on time:

SELECT sum(stop-start) FROM logs WHERE name = 'intern-mw' and
start >= '27-10-1999' AND stop < ('28-10-1999'::datetime + '1 day'::timespan);
sum
-------------------------
@ 12 hours 51 mins 4 secs
(1 row)

uups what's happening here ?

I've doublechecked the WHERE clause, It is ok, the right tuples are selected,
but 3h + 4.5h are not 13h! Wat I'm doing wrong here ?

It is possible to get the timespan in minutes only ? I mean the entire timespan
in minutes not the minutepart of the timespan.

Thanks,

Holm

--
FreibergNet Systemhaus GbR Holm Tiffe * Administration, Development
Systemhaus für Daten- und Netzwerktechnik phone +49 3731 781279
Unternehmensgruppe Liebscher & Partner fax +49 3731 781377
D-09599 Freiberg * Am St. Niclas Schacht 13 http://www.freibergnet.de/