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Re: Using quicksort for every external sort run - Mailing list pgsql-hackers

From Jeremy Harris
Subject Re: Using quicksort for every external sort run
Date
Msg-id 56686F67.4010303@wizmail.org
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In response to Re: Using quicksort for every external sort run  (Jeff Janes <jeff.janes@gmail.com>)
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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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