TIMESTAMP WITH TIME ZONE when I tried to do some date arithmetic on an ETL job to load into Postgres. Eventually I gave up, and fetched it back into Python and

TIMESTAMP WITH TIME ZONE when I tried to do some date arithmetic on an ETL job to load into Postgres. Eventually I gave up, and fetched it back into Python and did the arithmetic there before sending it on. It may have been that there is an obvious answer which I simply failed to find due to the fact that I hadn't used Oracle in a decade. But I went down a number of dead ends before coming up with an approach that worked. (And the person before me had simply not noticed the problem...)