Re: Abbreviated keys for Numeric

>>>>> "Tomas" == Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com> writes:

>> Right...so don't test a datum sort case, since that isn't supported
>> at all in the master branch. Your test case is invalid for that
>> reason.

Tomas> What do you mean by 'Datum sort case'?

A case where the code path goes via tuplesort_begin_datum rather than
tuplesort_begin_heap.

Tomas> The test I was using is this:

Tomas> select percentile_disc(0) within group (order by randnum) from stuff;

Sorting single columns in aggregate calls uses the Datum sort path (in
fact I think it's currently the only place that does).

Do that test with _both_ the Datum and Numeric sort patches in place,
and you will see the effect. With only the Numeric patch, the numeric
abbrev code is not called.

If you want a test that works without the Datum patch, try:

select count(*) from (select randnum from stuff order by randnum) s;

--
Andrew (irc:RhodiumToad)