"A. R. Van Hook" <hook@lake-lotawana.mo.us> writes:
> How does one sum interval sums?
> the following does not work:
> select sum(stop-start::interval) as total from startstop
Define "does not work"? What did you get, what were you hoping for?
Personally I'd drop the unnecessary cast, but AFAICS there are
appropriate operators at least as far back as 7.3.
regards, tom lane