The following bug has been logged online:
Bug reference: 3260
Logged by: Dhugael McLean
Email address: box@yourtechonline.com
PostgreSQL version: 8.1.8
Operating system: FreeBSD
Description: Subtracting intervals
Details:
select '1 day'::interval - '55 minutes'::interval;
?column?
-----------------
1 day -00:55:00
If the interval periods are both minutes (hours - hours, days - days, etc),
this works fine. Days - minutes seems to fail. This should output 23:05:00.
In case this was some weird casting error, I checked:
select interval '1 day' - interval '55 minutes';
and that failed as well.