Re: Very ineffective plan with merge join

On Thu, 15 Apr 2010, Kevin Grittner wrote:

> Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
>> I'm not sure how much it would help to increase the statistics
>> targets, but that would be worth trying.

Setting statistics to 1000 helps for that particular reduced query, but
full query (attached) is out of luck.

>
> I notice that the scan rowcount estimates are very accurate, there's
> that one hash join result that's way off, though.
>
> What's up with the sort of _accrged7200 (in the slower plan) taking
> in 3.5 million rows and putting out 1 row? There's something there
> I'm not understanding.
>
> -Kevin
>

Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg(at)sai(dot)msu(dot)su, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83