Pre-calculate hash join

From: warren(at)warrenandrachel(dot)com
To: pgsql-general(at)postgresql(dot)org
Subject: Pre-calculate hash join
Date: 2010-01-08 20:44:50
Message-ID: 22037187.72981262983490954.JavaMail.root@vcsmail.com
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When joining two large tables [common in warehousing], a hash join is commonly selected. Calculating hash values for the merge phase is CPU intensive. Is there any way to pre-calculate value hashes to save that time? Would it even grant any performance to skip the build phase of the hash join?

-Warren

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