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Re: Why is sorting on two columns so slower thansortingon one column? - Mailing list pgsql-hackers

From Robert Haas
Subject Re: Why is sorting on two columns so slower thansortingon one column?
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Msg-id AANLkTim+r8c92DDepkotBe1jgTDPz9c-oeA6V80XbYHw@mail.gmail.com
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In response to Re: Why is sorting on two columns so slower thansortingon one column?  (Simon Riggs <simon@2ndQuadrant.com>)
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On Mon, Dec 27, 2010 at 3:58 AM, Simon Riggs <simon@2ndquadrant.com> wrote:
> I think the answer is that only the first column comparison is
> optimised. Second and subsequent comparisons are not optimised.

What sort of optimization are you referring to here?

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

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