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From: Jeremy Harris <jgh@wizmail.org>
To: pgsql-hackers@postgresql.org
Subject: Re: Using quicksort for every external sort run
Date: Wed, 9 Dec 2015 18:13:59 +0000
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On 09/12/15 00:02, Jeff Janes wrote:
> The second one consumes that giant tape run along with 232 small tape
> runs.

In terms of number of comparisons, binary merge works best when the
inputs are of similar length.  I'd assume the same goes for n-ary
merge, but I don't know if comparison count is an issue here.
-- 
Cheers,
  Jeremy



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