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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Your opinion please :) explanation of my point of view
I'll take another stab at this:
In the last few months I have looked at/researched table partitioning, which you mention, implementing parallel processing, use of index organized tables (IOT's), bitmap-join indexes. My datawarehouse was built using Oracle Standard Edition and then we upgraded to Enterprise edition so now we are rebuilding the foundation and framing of the house that's already been built. Some of these will fit into your existing document framework.
-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Juan Cachito Reyes
Pacheco
Sent: Friday, February 27, 2004 10:59 AM
To: oracle-l_at_freelists.org
Subject: Re: Your opinion please :) explanation of my point of view
Thanks Dave
----- Original Message -----
From: "Dave Phillips" <dphillips_at_gasper-corp.com>
To: <oracle-l_at_freelists.org>
Sent: Friday, February 27, 2004 11:55 AM
Subject: RE: Your opinion please :) explanation of my point of view
Okay, I usually only post when I have a question for the Oracle Guru's
on the list. I realized real quick like that the collective knowledge of
the Oracle Brainiacs here didn't need any of my help. I seem to be too
busy running around catching all this free oracle manna dropping from
the sky and wondering just what these folks eat/drink to know all this
stuff (They seem to have a common beverage but this RTFM they mention ..
Is that like a low carb food or what?)
Now, since you are asking my opinion on a document for DBA's that don't
know much, hey I figure I can qualify :)
I think your attempt to write a paper and share knowledge is
commendable. It's more than I could do at this point.
I have looked it over and have provided the following comments (FWIW) 1. I don't think the title should be 101 Tuning tips as much as "101 things that effect performance". Tuning is a process for identifying and performance issues. (Cary's book recommended here). 2. The 'resolves 90% of tuning problems.." statement is a dangerous one for a new DBA to hear. I have a whole bookshelf full of Oracle reference materials and 100 stacks of oracle articles (yours included) and I'd be safe to say that 100% couldn't solve my tuning problems if I have poor application design and it's running on a customers server that houses the app, the database, acts a domain controller and they all share the same RAID5 and 1G of ram. The only way a book or article will help me here is if I hit someone with it enough to get them to change. (let me savor this thought for a moment.....ok ) I think you paper is a good start, but I think the newer DBA's would be better served by less of a checklist approach and a little more of 'things that effect optimizer performance', things that effect index performance', 'Initial database parameters that effect performance'. More of a cause and effect approach with examples. That I believe would be more beneficial.
Sorry for the short novella, and thanks for letting me express my opinion.
David Phillips
Oracle 8i OCP
BAARF member#30
-----Original Message-----
From: Juan Cachito Reyes Pacheco [mailto:jreyes_at_dazasoftware.com]
Sent: Thursday, February 26, 2004 2:33 PM
To: oracle-l_at_freelists.org
Subject: Re: Your opinion please :) explanation of my point of view
Yes, this resolves the 90% of tunning problems in standar database
edition.
The reason is simple, in STANDARD edition (no parallel execution, etc.)
, at
least here in Bolivia, you don't have lots and lots of users, maximum
20,
the biggest table I have has 3,000,000 of records.
So the tunning problems are not really serious in 9i.
Now I challenge you which tunning problem is not considered in that
paper,
and should be :=)
> Well, if your paper "solves 90% of tuning problems", than this list
can
> rest peacefully...
>
> Igor Neyman, OCP DBA
> ineyman_at_perceptron.com
>
>
>
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org
> [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Juan Cachito Reyes
> Pacheco
> Sent: Thursday, February 26, 2004 10:34 AM
> To: oracle-l_at_freelists.org
> Subject: Re: Your opinion please :) explanation of my point of view
>
> thanks to you, this will improve a lot, the point is that I don't have
> too
> much time.
>
> If you have something brief, for exapmle I got from Tom Kyte,
"function
> in
> c+ can be up to 2 times faster", to have an idea when to use c and
when
> not,
> or from tom kyte to "try to do in plsql, if you can't use java and if
> you
> can't use c++", this are the kind of guide and test takes looooong
time
> to
> find.
> Even when some of you could think this is a list of tips I got
randomly,
> it
> is not, in that paper there is all the tunning tips you need to solve
> 90% of
> tunning problems in standard edition, so don't think I take randomly
> some
> tips and put in a paper briefly and said "this is my paper"
> ----- Original Message -----
> From: "Freeman, Donald" <dofreeman_at_state.pa.us>
> To: <oracle-l_at_freelists.org>
> Sent: Thursday, February 26, 2004 11:24 AM
> Subject: RE: Your opinion please :) explanation of my point of view
>
>
> Let me chime in my 2 cents here. I printed and reviewed your document
> and
> noted a few
> things that I will discuss with my co-DBA. I liked the article because
> in a
> short
> document you summarized a number of things that were important in your
> experience. Some of
> them seem relevent to what I am doing so I will spend some time to
check
> them out. As
> far as you posting it, I personally try to pass on tips and tricks as
I
> learn them and I appreciate
> that behavior in others.
>
> As what we do is often a competitive business I have not often
> encountered
> people personally
> who freely give away valuable information which they struggled to
gain.
> The
> top-level professionals
> who answer questions here are doing 'pro-bono' work for which I am
> grateful.
> It's the same advice
> that people pay them for. In real life I'm beginning to think it's
> pretty
> remarkable when somebody
> says, "Come on over, I'll show you how it works." The lists are very
> valuable to me. I'm not in a
> position to travel to conferences, seminars, and attend workshops to
> improve
> my skills and don't
> work for an employer who values (or pays for) this kind of stuff.
>
> I think you are pretty brave for posting your 'baby.' I have been
> holding
> my breath because
> I thought it might provoke a lot of disagreement or outright
> disparagement
> of your effort. At
> this point I don't know enough to say if what you have posted is
> altogether
> technically accurate but
> I always check 'free' advice anyway.
>
> You are correct, I think, in the way some people approach books. I am
> struggling to understand
> some of the features in Oracle and have quite an extensive library of
> Oracle
> books. Most of them
> I haven't read cover to cover. I tend to read them a chapter, or even
a
> paragraph at a time depending
> on what my issue is. I download a lot of papers, "how-too's", tips and
> tricks.
>
> The value of the books on the market to me is to answer the bigger
> questions
> of why and when (or how much)
> instead of what and how. Its always helpful to me when somebody says,
> "On an
> OLTP system is should be X and
> on a DS system it should be Y." It gives me a point at which to start
> looking. The oracle books usually
> provide the exact syntax describing how a feature or function is
> implemented
> but don't answer the question,
> for me, "Is this an appropriate thing to do in a small datawarehouse
> environment..." I know, "It depends."
>
> So, thanks for posting!
>
> Don Freeman
> Oracle 9i OCP
>
>
>
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org
> [mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Juan Cachito Reyes
> Pacheco
> Sent: Thursday, February 26, 2004 9:05 AM
> To: oracle-l_at_freelists.org
> Subject: Re: Your opinion please :) explanation of my point of view
>
>
> Thanks for your opinion.
>
> Now if you think "kill lazy and bad dbas", I can't do too much about
> this.
> I think every one likes his job, and a paper like this can wake up his
> interest in reading to a bad dba, and help to introduce a good dba who
> is
> starting to read.
>
> Yes this is true, the idea is to introduce to all this people to
> tunning.
> I think if every one would read the Oracle document as they should,
50%
> of
> the book would be useless. If you take randomly a good tunning book
and
> seek
> the same in Oracle tunning documentation, 90% is in the Oracle
> documentation, at least!!
>
> But even when you read and got an OCP, you need some guide about what
> you should check first, better and simple explanations, for example
> about
> CURSOR_SPACE_FOR_TIME there is not a clear explanation about when
to
> use
> them.
> You need a guide that introduce to tunning. to make you understand
what
> is
> important and what is the most important.
>
>
> ----- Original Message -----
> From: "Igor Neyman" <ineyman_at_perceptron.com>
> To: <oracle-l_at_freelists.org>
> Sent: Thursday, February 26, 2004 9:53 AM
> Subject: RE: Your opinion please :) explanation of my point of view
>
>
> > If "newbie DBA" doesn't like to read, he/she'd better be in
different
> > business...
> >
> > Igor Neyman, OCP DBA
> > ineyman_at_perceptron.com
> >
> >
> >
> > -----Original Message-----
> > From: oracle-l-bounce_at_freelists.org
> > [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Juan Cachito
Reyes
> > Pacheco
> > Sent: Thursday, February 26, 2004 7:48 AM
> > To: oracle-l_at_freelists.org
> > Subject: Re: Your opinion please :) explanation of my point of view
> >
> > Thanks for your opinion, tellme what do you think, about this.
> >
> > Point by point
> > 1) About the set of checklist, I agree, but the goal is to introduce
> to
> > tunning, in the market there are several excellent tunning books,
> > (including
> > the documentation where is almost all), but people don't read them.
> > I decided something short, a checklist explaining very very briefly
> what
> > you
> > can tune, the most important, the first steps, for newbies, now if
you
> > want
> > more information, you can go to documentation.
> > For example about statistics, I had two pages of a BRIEF
explanation,
> > but no
> > body is going to read all that, because instead of 8 pages it will
be
> 60
> > pages, it will be preferable to read the documentation, but several
> > questions you should had read some moment, shows people don't like
to
> > read,
> > people who never took the time to read neither concept manual, so I
> > decided
> > to explain the most important, briefly.
> >
> > For example, about statistics, the explanation is very short
> > 1.1 Statistics
> > The optimizer works based on statistics, if they are old, or
> inaccurate
> > you'
> > ll get a wrong execution plan.
> >
> > You must recalculate statistics every time an important change had
> > happened
> > in it:
> >
> > . Periodically, based on normal changes in a database
> >
> > . After importing a big amount of data
> >
> > . When distinct values in primary columns change
> >
> > . After creating indexes and table
> >
> > 1.1.1 Test database
> > If this is the first time you get statistics, you must remember some
> > database has fixed execution plans, or any other consideration can
> cause
> > a
> > statistics recalculation cause serious problems, as general rule do
it
> > first
> > in ha test database, before doing in the production database.
> >
> > 1.1.2 Recalculating statistics
> > Oracle recommends DON'T USE ANALYZE to gather statistics, the
package
> > USE
> > DBMS_STATS, this package get more statistics, specially for new
> > features.
> >
> > Don't execute DBMS_STATS on SYS schema.
> >
> > This command has dozens of options, like parallel execution, etc.
etc.
> > you
> > must read them.
> >
> > To gather all statistics
> >
> > EXEC DBMS_STATS.GATHER_DATABASE_STATS();
> >
> > To gather statistics in a schema:
> >
> > EXEC DBMS_UTILITY.ANALYZE_SCHEMA('ADM','COMPUTE');
> >
> > To gather statistics in a schema, more precisely, the one we use,
> > because
> > our database is a small database:
> >
> > EXEC DBMS_STATS.GATHER_SCHEMA_STATS( OWNNAME=>'ADM',
> > ESTIMATE_PERCENT=>100,METHOD_OPT=>'FOR ALL COLUMNS SIZE SKEWONLY');
> >
> >
> > What you understand after this is
> > -optimizer needs statistics
> > -changing statistics can cause you problems, first use a test
database
> > -use dbms_stats not analyze
> > That's all, and I think this is the basic thing you have to
> understand,
> > I
> > know dbas (not ocps) who don't know that simple fact," they have to
> > recalculate statistics periodically". Because their database are
small
> > and
> > comparing with sql server it takes a similar amount of time to
> process,
> > they
> > don't see it as a problem or a mistake.
> >
> > 2)About the optimizer_index_caching I read a lot, because we have a
> > problem,
> > we solved setting this parameter, about this parameter I say:
> > "This parameter sets the possibility to find blocks accessed through
> an
> > index in memory.
> >
> > Default value is 0, 0 means that no one block accessed through index
> > will be
> > found in memory THIS IS FALSE. A value of 90% is advisable"
> >
> > Could you giveme an example how could I explain it better.
> >
> > 3) About
> > "but pays no attention to individual business processes (or indeed
> > development modules)."
> > Could you giveme an example what for example I could add ,
> > But I'm not explaining in this paper things like ORDERED hint,
because
> > for a
> > newbie, first he have to do the basic things, once he had done all
of
> > them,
> > if he continue having problems, then the correct way is to read a
more
> > serious document.
> > Because if you give advanced points, he will try them first, is like
> > special
> > hints, I think you heard about them, they are not in documentation
> > because
> > it could cause problems to new dbas, because they could try to use
> them
> > to
> > solve problem, when the reality is they can be used only
> exceptionally.
> > but
> > there are book out there once you get the enough experience you
could
> > buy
> > them.
> >
> > Now if you want another point of view, or a better idea about this,
> you
> > are
> > welcome :).
> >
> > ----- Original Message -----
> > From: "Niall Litchfield" <n-litchfield_at_audit-commission.gov.uk>
> > To: <oracle-l_at_freelists.org>
> > Sent: Wednesday, February 25, 2004 7:29 PM
> > Subject: RE: Your opinion please :)
> >
> >
> > hi
> >
> > I have to admit I don't like the paper much. it looks like a set of
> > checklists with little or no reasoning behind them. for example the
> > suggestions on optimizer_index_caching have just start at x and work
> > from
> > there. where x is apparently an arbitrary number.
> >
> > my deeper problem is that the article seems to suggest that it is
> > possible
> > to tune systems but pays no attention to individual business
processes
> > (or
> > indeed development modules). I disagree, the logical unit for tuning
> is
> > the
> > thing that runs badly, the logical time to do it is when writing the
> > code
> > for it. setting db wide parameters is sticking plaster on the
titanic.
> > perhaps.
> >
> > Niall
> >
> > -----Original Message-----
> > From: AC.GWIA.oracle-l_at_freelists.org
> > [mailto:AC.GWIA.oracle-l_at_freelists.org]
> > Sent: Wed 25/02/2004 18:41
> > To: jreyes_at_dazasoftware.com; oracle-l_at_freelists.org
> > Cc:
> > Subject: Your opinion please :)
> >
> >
> >
> > Hi I took sometime to do a paper, to help newbies in tunning, this
is
> > not to
> > become they expert, but at least they know there are statistics in
the
> > database
> >
> > If you get some time, and give some opinion about it, like the
> previous
> > mistake I did with IN function, you are welcome.
> > Or something important I'm missing (for newbies dbas of course).
> > Did you remember the first time you had a tunning problem, before
the
> > ocp,
> > and you didn't knew where to start to check,and lost long time,
> changing
> > some database parameter to see if that improved something, the idea
is
> > to
> > save that step.
> >
> >
> >
>
http://www.geocities.com/juancarlosreyesp/101basictunningonOracle9i.pdf
> >
> > Juan Carlos Reyes Pacheco
> > OCP
> >
> >
> > ----------------------------------------------------------------
> > Please see the official ORACLE-L FAQ: http://www.orafaq.com
> > ----------------------------------------------------------------
> > To unsubscribe send email to: oracle-l-request_at_freelists.org
> > put 'unsubscribe' in the subject line.
> > --
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> > -----------------------------------------------------------------
> >
> >
> >
> >
> >
-- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request_at_freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request_at_freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request_at_freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------Received on Fri Feb 27 2004 - 10:28:13 CST
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