Tom Lane wrote:
> Luis Amigo <lamigo@atc.unican.es> writes:
> > again join and geometry(it also failed in postgres 7.1.3)
>
> The join discrepancy is probably an artifact of your local qsort()
> behaving slightly differently for equal keys than everyone else's.
> Curious that it only affects these few queries, though.
>
> Geometry differences in the low-order digits are par for the course.
> I wouldn't even stop to think about it, except that I see that you
> are already using a platform-specific geometry comparison file
> (geometry-irix.out). Some digging in the CVS logs and mail archives
> shows that that file was submitted by Pete Forman in Oct 2000, and
> he was using
>
> > Architecture (example: Intel Pentium) : SGI MIPS 8000
> >
> > Operating System (example: Linux 2.0.26 ELF) : IRIX 6.5.5m
> >
> > PostgreSQL version (example: PostgreSQL-7.1): PostgreSQL-7.1
> >
> > Compiler used (example: gcc 2.8.0): MIPSPro 7.3
>
> Not clear at this point if the differences in your results are due to
> hardware, library version, or compiler version differences.
>
> regards, tom lane
I've reviewed the results, join differences seem to be conceptual
differences, expected result gives higher value to NULL that 0
(personally I think 0 is bigger than NULL).
Geometry differences are architectural round up differences (I think
that MIPS 10000 and 12000 may have corrected previous errors or might
be a different point-of-view about rounding)