Re: Sequential vs. random values - number of pages in B-tree - Mailing list pgsql-general

From Daniel Verite
Subject Re: Sequential vs. random values - number of pages in B-tree
Date
Msg-id e95bf02e-cd18-4a2b-8e78-80d3fd61b826@mm
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In response to Re: Sequential vs. random values - number of pages in B-tree  (Francisco Olarte <folarte@peoplecall.com>)
Responses Re: Sequential vs. random values - number of pages in B-tree  (Francisco Olarte <folarte@peoplecall.com>)
List pgsql-general
    Francisco Olarte wrote:

> unless you know of an easy way to generate a random permutation on the
> fly without using a lot of memory, I do not.

It could be done by encrypting the stream.

For 32 bits integers:
https://wiki.postgresql.org/wiki/Skip32

For 64 bits integers:
https://wiki.postgresql.org/wiki/XTEA


Best regards,
--
Daniel Vérité
PostgreSQL-powered mailer: http://www.manitou-mail.org
Twitter: @DanielVerite


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