Re: wip: functions median and percentile

2010/10/2 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:
> Hitoshi Harada <umi(dot)tanuki(at)gmail(dot)com> writes:
>> Another suggestion?
>
> The implementation I would've expected to see is to do the sort and then
> have two code paths for retrieving the median, depending on whether the
> sort result is all in memory or not.
>

Hm? The problem we encountered in the middle of the patch is there is
no chance to call tuplesort_end if median is called in moving frame
window aggregate because final function is called multiple times
during moving. The nearest pattern was array_agg() which uses
on-memory state and throw its responsibility to clear memory to
executor (nodeAgg / nodeWindowAgg). Am I missing something?

Regards,

--
Hitoshi Harada