Re: Tested 11g OLTP compression and found rather serious issue

From: Tamkatten_at_gmail.com <tamkatten_at_gmail.com>
Date: Tue, 11 Aug 2009 03:53:39 -0700 (PDT)
Message-ID: <447c0d8b-1071-4a1e-962c-505c6e5a439a_at_s31g2000yqs.googlegroups.com>

On 10 Aug., 08:10, "Jonathan Lewis" <jonat..._at_jlcomp.demon.co.uk> wrote:
> "Tamkat..._at_gmail.com" <tamkat..._at_gmail.com> wrote in message
>
> news:c3c48bcf-640d-4351-801c-9b6f13267069_at_j9g2000vbp.googlegroups.com...
>
> >Hi again,
>
> >Further findings on OLTP compression :
>
> But this is just like your previous test.
> You are testing an OLTP feature with a DSS type of update.
>
> General point with Oracle - understand what a feature is for,
> and then use it when it is supposed to be used, and think
> carefully before using it where it is not supposed to be used.
>
> Congratulations, by the way, on thinking up a couple of
> good test demonstrations of the types of scenario where
> online compression is not appropriate.
>
> --
> Regards
>
> Jonathan Lewishttp://jonathanlewis.wordpress.com
>
> Author: Cost Based Oracle: Fundamentalshttp://www.jlcomp.demon.co.uk/cbo_book/ind_book.html
>
> The Co-operative Oracle Users' FAQhttp://www.jlcomp.demon.co.uk/faq/ind_faq.html

Hi Jonathan,

Thanks for your comments.

True, this is not strictly OLTP.

Just a comment on evaluating a feature before use : I guess the challenge here (and in general) is that the terms change so rapidly.

My experience is that almost every system encounters a mixed workload, sooner of later. The rapidly changing business requirements (that being from a short-term wish of saving expenses, developing business or whatever) make it hard for the DBA to predict the future usage of the data. A set of seemingly strict OLTP tables may be included in some DSS/WH application, changing the volatility of those tables suddenly and/or steadily over time.

The DBA can thus suggest a set of proper/ideal solution for that problem (at least from the DBA perspective), but in this world, his/ her solution will be mercilessly cost/benefit evaluated and may be picked or chosen.

The good news is that that DBA's work won't be boring, nor obsolete in the future...:-)

• Kenneth Koenraadt

Received on Tue Aug 11 2009 - 05:53:39 CDT