Re: funkiness with '1999-12-31 19:00:00-05'::timestamp with time zone

Josh Kupershmidt <schmiddy@gmail.com> writes:
> I've come across a puzzling situation with a table having a timestamp
> with time zone column. This column is full of values displaying
> exactly as '1999-12-31 19:00:00-05', but for some reason Postgres is
> treating some of these identical-seeming timestamps as being
> different.

Is this installation using float or integer timestamps?  If the former,
it might be interesting to look at the subtraction result
    ts - '1999-12-31 19:00:00-05'::timestamptz
I'm thinking some of them might be different by submicrosecond amounts.

            regards, tom lane