Greg Stark escribió:
> On Mon, Oct 19, 2009 at 8:56 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Greg Stark <gsstark(at)mit(dot)edu> writes:
> >> The run-time of CLUSTER doesn't vary very much based on whether the
> >> data is already in index order or not. The number of passes only grows
> >> like log(n) of the size of your data and if you set
> >> maintenance_work_mem large enough (somewhere around 100MB-1GB) the
> >> constants are small enough that you're unlikely to even outgrow a
> >> single pass (plus a final merge though)
> > Uh ... what? It's not based on the sort code, unless someone rewrote it
> > since I looked last. It's an index scan and will definitely depend on
> > the index ordering.
> Er, uh, of course. I wonder what I was thinking.
Your patched version of course.
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.
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