Sorry, I did wrong test.
> > > Noah Misch <noah@leadboat.com> writes:
> > > > If the attached patch version looks reasonable, I will commit it.
> > >
> > > The test case is completely bogus, as the query explained is significantly
> > > different from the query executed. I'm not sure whether you can just
> > > remove the extra ORDER BY column without getting machine-dependent
> > > results, though.
> >
> > Each query tests something slightly different. The EXPLAIN verifies that we
> > can MergeAppend given this query structure, and the plain SELECT verifies that
> > any join tree contortions we made to achieve that do not change the answer.
>
> I think Tom said that the second query can yield the same result
> even if the 2nd column in orderby is removed so the pertinence of
> it seems doubtful. Actually the altered query gave me the same
> result on my workset (CentOS6.5/x86-64).
No, no! It was actually returned a *different* result. I
accidentially(?) added 'desc' to the '2'. Please forget it.
regards,
--
Kyotaro Horiguchi
NTT Open Source Software Center
