Re: hash options

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От David W Noon
Тема Re: hash options
Дата
Msg-id 20120122194124.30c5c19b@karnak.local
обсуждение исходный текст
Ответ на hash options  ("Little, Douglas" <DOUGLAS.LITTLE@orbitz.com>)
Список pgsql-general
On Sun, 22 Jan 2012 09:59:55 -0600, Little, Douglas wrote about
[GENERAL] hash options:

>I'm working on a data warehouse dimensionalization process   where I
>need to hash a text string to use as the key. I've implemented with
>MD5.  It works fine,  the problem I have is the size of the md5 (32
>bytes) is often longer than the original string - thus not
>accomplishing what I want - space savings.
>
>Does anybody have alternative hash function recommendations?

Try CRC32, possibly augmented by a CRC16 in a separate attribute.

I have CRC functions for PostgreSQL, written in C, and will make them
available to anybody who wants them.
--
Regards,

Dave  [RLU #314465]
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dwnoon@ntlworld.com (David W Noon)
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