Re: Is SQL procedural or non-procedural?

From: David Cressey <dcressey_at_verizon.net>
Date: Tue, 13 Jun 2006 11:46:03 GMT
Message-ID: <%zxjg.3573$n93.2910@trndny07>

"Paul" <paul_at_see.my.sig.com> wrote in message news:g2hr82dcti546301pl4d0qkk4ufhke50ep_at_4ax.com...
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> "David Cressey" <dcressey_at_verizon.net> wrote:
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> > By contrast, some other products had cost based optimization, and the
> > programmers could focus on what data they wanted, instead of how to
access
> > it.
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> I'd suggest that you take a look at Jonathan Lewis' book "CBO, the
> fundamentals" to see how wrong you are there.
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> Sure, the CBO is *_meant_* not to worry, but boy, it does!
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I'm familiar with the optimizer that was built into DEC Rdb/VMS. It had the effect that I described in my earlier post.

People who are familiar with DB2 assure me that the DB2 optimizer was also very good.

I've seen Oracle shops converting from RBO to CBO, and they need to go through a cultural shift.

What does "CBO, the fundamentals" teach? Received on Tue Jun 13 2006 - 06:46:03 CDT