Re: Randomisation for ensuring nlogn complexity in quicksort - Mailing list pgsql-hackers

From Robert Haas
Subject Re: Randomisation for ensuring nlogn complexity in quicksort
Date
Msg-id CA+TgmoaMe91R_3PptRpBbJp4X7cVoeOeKQOXcB4SNPJYCUKp2A@mail.gmail.com
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In response to Re: Randomisation for ensuring nlogn complexity in quicksort  (Atri Sharma <atri.jiit@gmail.com>)
Responses Re: Randomisation for ensuring nlogn complexity in quicksort
List pgsql-hackers
On Tue, Jul 2, 2013 at 12:33 AM, Atri Sharma <atri.jiit@gmail.com> wrote:
>> If you want to get a useful response to your emails, consider
>> including a statement of what you think the problem is and why you
>> think your proposed changes will help.  Consider offering a test case
>> that performs badly and an analysis of the reason why.
>
> Right, thanks for that. I will keep that in mind.
>
> I was thinking about *mostly sorted* datasets, consider the following:
>
> 10 11 12 4 5 6 1 2

I think if you'll try it you'll find that we perform quite well on
data sets of this kind - and if you read the code you'll see why.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company



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