"Hitoshi Harada" <umi.tanuki@gmail.com> writes:
>> I hadn't realized that this would be relevant to window functions.
>> Now that I know that, I propose fixing tuplestore for multiple
>> positions and committing it separately, before I go back to the CTE
>> patch. Then Hitoshi-san will have something he can work with too.
> Yes, tuplestore multiple positioning will give the greate help to the
> window function. Ideally, it is better that tuplestore'd have all the
> positions and have some kind of capability to discard old rows so that
> it can stay in TSS_MEM, which helps window function's sliding frame.
Okay, there's a patch in CVS HEAD that works this way. Let me know if
it needs further tweaking for your purposes.
regards, tom lane