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Oracle Cost Based Optimizer

From: <jeremy_at_cs.unm.edu>
Date: 1997/07/17
Message-ID: <869155958.18595_at_dejanews.com>#1/1 







I have a certain question, and currently I have not been able to find the
answer either way on this one.



I'm working on a project that involves Oracle v7.3.2, right now we are
using rule based optimization. I have heard horror stories about Oracle's
CBO, (i.e. not picking the optimal path for a query, not returning.. a
very undesirable feature). And most of the consensus of other parties
is that if you use a version of Oracle before v7.3 then USE RBO OR ELSE!!!



I have heard rumors that the CBO will be fixed in v7.3 and above, and I
have heard rumors that the CBO won't be fixed until v8...



Does anyone know which is it? or is anyone running v7.3 and the CBO with
no problems?



Also... I have read the Oracle documentation on their Optimizer... Does
anyone know where I can get a hold of some material that covers the
analysis of the Oracle optimizer... maybe as compared to other optimizers
(i.e. INGRES)...




  -Jeremy


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Received on Thu Jul 17 1997 - 00:00:00 CEST












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