On Mon, 2009-12-14 at 09:58 -0500, Tom Lane wrote:
> In particular, the granularity examples you give seem to assume that
> the underlying datatype is exact not approximate --- which among other
> things will mean that it fails to work for float timestamps. Since
> timestamps are supposedly the main use-case, that's pretty troubling.
Additionally, granularity for timestamps is not particularly useful when
you get to things like "days" and "months" which don't have a clean
algebra.
Is the granule there only to try to support continuous ranges? If so, I
don't think it's necessary if we expose the API differences I outlined
in another email in this thread. Also, that would mean that we don't
need a granule for float, because we can already treat it as discrete*.
Regards,Jeff Davis
*: nextafter() allows you to increment or decrement a double (loosely
speaking), and according to the man page it's part of C99 and
POSIX.1-2001.
