Re: Abbreviated keys for Numeric

On 21.2.2015 02:00, Andrew Gierth wrote:
>>>>>> "Tomas" == Tomas Vondra <tomas.vondra@2ndquadrant.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.

D'oh! Thanks for the explanation.


-- 
Tomas Vondra                http://www.2ndQuadrant.com/
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