Re: Windowing Qual Pushdown

2010/3/23 Daniel Farina <drfarina(at)acm(dot)org>:
> On Tue, Mar 23, 2010 at 12:19 AM, Hitoshi Harada <umi(dot)tanuki(at)gmail(dot)com> wrote:
>> If you implement that optimization, we need have kind of
>> implicit, homologous qual information. Sure, it's possible.
>
> I'm not sure precisely what you mean here.  Do you predict the
> mechanism will be complicated?  It's been a burning itch of mine for a
> little while now.  I do not know exactly how windowing functions look
> in Query values just yet, although I'm very familiar with older
> structures there.

I believe the changes will probably not be 2-3 lines (ie. a member
added to Query structure, etc) if I try it. But the optimizer part is
too complicated to me so that I am not sure, either. My idea above is
that the similar mechanism you see in GROUP BY optimization will help
you and the issue is not so particular about window functions.

Regards,

--
Hitoshi Harada