Re: Multi-pass planner
От | Jeff Janes |
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Тема | Re: Multi-pass planner |
Дата | |
Msg-id | CAMkU=1wnmcZOX3B9Qy79qtVvAr9hx=VvxVZOB-B0C82B_ZPdng@mail.gmail.com обсуждение исходный текст |
Ответ на | Re: Multi-pass planner (Claudio Freire <klaussfreire@gmail.com>) |
Ответы |
Re: Multi-pass planner
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Список | pgsql-hackers |
<div dir="ltr">On Fri, Apr 19, 2013 at 2:24 PM, Claudio Freire <span dir="ltr"><<a href="mailto:klaussfreire@gmail.com"target="_blank">klaussfreire@gmail.com</a>></span> wrote:<br /><div class="gmail_extra"><divclass="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #cccsolid;padding-left:1ex"><div class="im"><br /></div>Especially if there's some locality of occurrence, since analyze<br/> samples pages, not rows.<br /></blockquote></div><br /></div><div class="gmail_extra" style="style">But it doesn'ttake all rows in each sampled page. It generally takes about one row per page, specifically to avoid the problemyou indicate. Maybe it is possible to trick it into taking too many (for example, if most pages are completely empty),but I haven't experienced that as being a problem.</div><div class="gmail_extra" style="style"><br /></div><div class="gmail_extra"style="style">Cheers,</div><div class="gmail_extra" style="style"><br /></div><div class="gmail_extra"style="style">Jeff</div></div>
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