From: | Christopher Browne <cbbrowne(at)acm(dot)org> |
---|---|
To: | pgsql-performance(at)postgresql(dot)org |
Subject: | Tuning Techniques To Avoid? |
Date: | 2004-01-02 12:33:46 |
Message-ID: | m37k0aa5sl.fsf@wolfe.cbbrowne.com |
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Lists: | pgsql-performance |
Here's a scheme for query optimization that probably needs to be
avoided in that it would run afoul of a patent held by Oracle...
It looks like what they have patented is pretty much a "greedy search"
heuristic, starting by finding the table in a join that has the
greatest selectivity (e.g. - where the number of entries selected is
cut the most by the selection criteria), and then describes how to
search for the "best" approach to joining in the other tables.
--
output = reverse("gro.mca" "@" "enworbbc")
http://www.ntlug.org/~cbbrowne/nonrdbms.html
"If I could find a way to get [Saddam Hussein] out of there, even
putting a contract out on him, if the CIA still did that sort of a
thing, assuming it ever did, I would be for it." -- Richard M. Nixon
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