Re: Unknown SQL

From: Philip Lijnzaad <lijnzaad_at_ebi.ac.uk>
Date: 31 May 2001 09:19:32 +0100
Message-ID: <u7k82yvskr.fsf_at_sol6.ebi.ac.uk>


On Thu, 31 May 2001 03:12:21 +0200,
"Carl" == Carl Rosenberger <carl_at_db4o.com> wrote:

>> of your experiments, I do not know what you did wrong to cause the
>> performance problems you saw. My guess is you did not have the DBMS
>> calculate the statistics properly.

Carl> Vadim has just posted the solution. The optimizer was not able to Carl> understand GROUP BY statements.

If I read his post correctly, this is not a problem with the view per se, but with the fully expanded query being too complex. I.e., the equivalent (fully expanded) query would have exactly the same performance. Is that correct, Vadim?

                                                                      Philip
-- 
If you have a procedure with 10 parameters, you probably missed some. (Kraulis)
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Received on Thu May 31 2001 - 10:19:32 CEST

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