Re: Re: Postgres int rounding

> Is postgres going to use the scientific method of rounding or just
> the simple one? Or even make it configurable. As I recall, the
> scientific method says that 4.5 should be rounded to 4 and 5.5 should
> be rounded to 6. The idea was that even numbers were easier to work
> with and rounding all the x.5 numbers up as the common method says
> will eventually skew your average. Rounding evens down and odds up
> would probably generate a number of bug reports from people who are
> not aware of this though...

I think some standard required the even/odd rounding behavour.

>
> -Michael
>
> > The fact that 5*27.81*100 != 27.81*100*5 is certainly a
> > garden-variety floating-point roundoff error. However, I think
> > Max has a fair complaint here: it seems float-to-int8 conversion
> > is truncating, not rounding like the other conversions to integer
> > do.
> >
> > regression=# select 4.7::float8::int4;
> > ?column?
> > ----------
> > 5
> > (1 row)
> >
> > regression=# select 4.7::float8::int8;
> > ?column?
> > ----------
> > 4
> > (1 row)
> >
> > Seems to me this is a bug we should fix.
>
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