Re: proposal: rounding up time value less than its unit.

On 2014-08-26 16:16:32 -0400, Robert Haas wrote:
> On Sat, Aug 23, 2014 at 6:39 PM, Greg Stark <stark@mit.edu> wrote:
> > On Sat, Aug 23, 2014 at 9:38 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >>
> >> Ah.  Okay, but then what's wrong with the original proposal of "use ceil()
> >> instead of floor()"?  Basically I think the idea of treating fractions
> >> less than one differently from fractions greater than one is bogus; nobody
> >> will ever find that intuitive.
> >
> > Or make it an error to specify a value that rounds to 0 but isn't 0.
> 
> I liked David Johnston's even stronger suggestion upthread: make it an
> error to specify a value requires rounding of any kind.  In other
> words, if the minimum granularity is 1 minute, you can specify that as
> 60 seconds instead, but if you write 59 seconds, we error out.  Maybe
> that seems pedantic, but I don't think users will much appreciate the
> discovery that 30 seconds means 60 seconds.  They'll be happier to be
> told that up front than having to work it out afterward.

Is the whole topic actually practically relevant? Afaics there's no
guc's with a time unit bigger than GUC_UNIT_S except log_rotation_age
where it surely doesn't matter and no space unit bigger than
GUC_UNIT_BLOCKS/GUC_UNIT_XBLOCKS.
In theory I agree with you/$subject, but I don't really see this worth
much effort.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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