Re: Partitioning - Mailing list pgsql-general

From Kyotaro HORIGUCHI
Subject Re: Partitioning
Date
Msg-id 20150119.174206.239009046.horiguchi.kyotaro@lab.ntt.co.jp
Whole thread Raw
In response to Re: Partitioning  (John R Pierce <pierce@hogranch.com>)
List pgsql-general
Hi,

At Mon, 19 Jan 2015 00:14:55 -0800, John R Pierce <pierce@hogranch.com> wrote in <54BCBCFF.5040100@hogranch.com>
> On 1/18/2015 11:59 PM, James Sewell wrote:
> >
> > Actually this brings up another question, if I have an unique integer
> > index of 2.gb <http://2.gb> what percentage would I expect to read for
> > a value that was higher or lower than all index values?
>
> a couple 8k blocks.  its a b-tree.

Yeah, scanning children reading highest/lowest values for each of
them would make it faster than the first single query.

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center



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