Re: sorting problem

From: Bruno Wolff III <bruno(at)wolff(dot)to>
To: Greg Stark <gsstark(at)mit(dot)edu>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, pgsql-general(at)postgresql(dot)org
Subject: Re: sorting problem
Date: 2004-12-17 21:19:34
Message-ID: 20041217211934.GB2119@wolff.to
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On Fri, Dec 17, 2004 at 15:12:18 -0600,
Bruno Wolff III <bruno(at)wolff(dot)to> wrote:
> On Fri, Dec 17, 2004 at 15:36:58 -0500,
> Greg Stark <gsstark(at)mit(dot)edu> wrote:
> >
> > Isn't that still nlog(n)? In the end you're going to have read in every page
> > of the index including all those non-leaf pages. Aren't there nlog(n) pages?
>
> The depth of the tree is log N, but there are only N nodes. I think you
> can treat the amount of information at each node as constant.

That should have been 2N-1 nodes.

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