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

From Atri Sharma
Subject Re: Randomisation for ensuring nlogn complexity in quicksort
Date
Msg-id CAOeZVidTsYUL57Mjp0iPaXZ=5OOoeGfr4Sx_pAk805yixz+TjQ@mail.gmail.com
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In response to Re: Randomisation for ensuring nlogn complexity in quicksort  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: Randomisation for ensuring nlogn complexity in quicksort
List pgsql-hackers
On Tue, Jul 2, 2013 at 5:20 PM, Robert Haas <robertmhaas@gmail.com> wrote:
> 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.

Right, let me read the code again from that viewpoint.

Thanks a ton for your help!

Regards,

Atri


--
Regards,

Atri
l'apprenant



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