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the IN club: Oracle "unpublished" information

From: Charles Schultz <>
Date: Wed, 14 Mar 2007 09:00:47 -0500
Message-ID: <>

Good day, all,

No, I am not offering any inside or exclusive information. I wish I could. =)

Rather, I am curious about many things Oracle, and in particular, how do you folks go about talking nicely with Oracle Developers and decision-makers? I am a bit frustrated by Oracle Support's obdurate stance to maintain
"internal" information as "classified" or "unpublished". In my quest to
learn more about How Oracle Works, I usually end up bugging people on this list because Oracle Support refuses to answer my questions (except on rare occasions). Can one join a well-respected OUG and gain access to some players? What other resources are there?

For instance, I was recently trading emails with Wolfgang Breitling, and he was patiently clarifying his paper "Joins, Skews and Histograms" (with kudos to Alberto Dell'Era). For an extremely simple case (join a 20 row table to a 40 row table where half of the rows from the first are repeated x4 in the latter), Wolfgang (and Alberto) demonstrate that Oracle uses a highly complex algorithm to calculate cardinality only when frequency histograms are used (as opposed to SIZE AUTO or SIZE SKEW, or no stats). The kicker is that the estimated cardinality is really bad (45% error). I filed an SR with Oracle to ask "why" and was given the standard boilerplate.

Granted, I still have a long way to go before anyone would even consider me expert material, but it does not take a genius to scratch his head and go
"huh?". I can imagine that Oracle justifies such a complex algorithm because
they want to be able to use it consistently for complex situations. But why for such a simple case?

My hat is off to folks like Alberto who apply their significant intellect and experience to the enigma of "what the heck is going on." Is there any recourse to gently nudge Oracle Development towards a simpler solution for a simple case? Or am I totally off my rocker and just way too naive to even be in this discussion?

Charles Schultz

Received on Wed Mar 14 2007 - 09:00:47 CDT

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