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Re: [PERFORM] Bad n_distinct estimation; hacks suggested?
- From: Josh Berkus <josh(at)agliodbs(dot)com>
- To: pgsql-perform <pgsql-performance(at)postgresql(dot)org>, pgsql-hackers(at)postgresql(dot)org
- Subject: Re: [PERFORM] Bad n_distinct estimation; hacks suggested?
- Date: Sat, 23 Apr 2005 16:53:16 -0700
- Message-id: <200504231653(dot)16317(dot)josh(at)agliodbs(dot)com>
People, > Can someone whose math is more recent than calculus in 1989 take a look at > that paper, and look at the formula toward the bottom of page 10, and see > if we are correctly interpreting it? I'm particularly confused as to > what "q" and "d-sub-n" represent. Thanks! Actually, I managed to solve for these and it appears we are using the formula correctly. It's just a bad formula. -- --Josh Josh Berkus Aglio Database Solutions San Francisco
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- From: Josh Berkus
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