From: | David W Noon <dwnoon(at)ntlworld(dot)com> |
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To: | pgsql-general(at)postgresql(dot)org |
Subject: | Re: hash options |
Date: | 2012-01-22 19:41:24 |
Message-ID: | 20120122194124.30c5c19b@karnak.local |
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Lists: | 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(at)ntlworld(dot)com (David W Noon)
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