Julian Scarfe <julian(dot)scarfe(at)ntlworld(dot)com> writes:
>> It seems I've chosen the wrong type. Or is there another solution?
> Correct diagnosis. You need the "interval" type, not the "time" type for
> your second field. Interval is a time difference between two timestamps,
> for example the time between the start and the finish of a race.
Right. "time" is intended for time-of-day values; so taking the sum
would be a nonsensical operation.
regards, tom lane