Re: My RMAN script of full backup

From: Mladen Gogala <>
Date: Wed, 2 May 2012 21:53:18 +0000 (UTC)
Message-ID: <jnsace$on5$>

On Sun, 29 Apr 2012 22:16:52 -0700, Noons wrote:

> I ensure that once an average SQL goes from dev to prod, its plan
> doesn't change for the worse. As well as collect stats regularly on low
> volatility objects. Can't remember the last time we got a "runaway"
> prod performance problem caused by wild SQL plans - other than the odd
> bu^H^Hfeature. And that's about it. Got better things to do with my
> time than "death-by-sql-tuning". KISS. Like it or not.

Well, when I said "SQL Tuning", I had in mind help to developers. Applications grow, objects are added, data models change, rarely for the better, things get messy. I am usually a go-to person when there is a problem like this: this query runs for 3 minutes and it needs to be put into a user facing web application. A user will not wait for 3 minutes, period. Can you make it complete in 10 seconds or less? Tricks like clustering and result cache come in handy. A long time ago, the most expensive statement on the system was, believe it or not, "SELECT 1 FROM DUAL". That was a "keep alive SQL" executed by a gazillion of application servers: WL, JBoss and Tomcat. Also, caching calls to the address tables containing state, also made a big difference. Those tables are mostly read only and result cache can cut down load on the system drastically, at the expense of some memory. That type of thing still cannot be done by computers.

> Of course: I'm not on con-sultancy rates. So I do mostly things like
> tuning the OS/DB interface, move data based on usage patterns, take
> advantage of SAN tools and features, monitor and analyze usage trends
> for capacity planning - CPU, mem, and disk space - and design, test and
> configure new servers as well as plug holes in MS/SQL here and there. A
> much better use of the time I'm being paid for.

>> When Skynet becomes self aware, the DBA 1.0 personnel will become
>> obsolete and will be tehminated.

> Tell that to the hordes of "con-sultants" who tried to get me outsourced
> for the last 5 years... Apparently, upfront we had a "performance
> problem". Even though no one has been able to pinpont exactly what that
> problem is. I'm sure as soon as some got in, they'd find "heaps of
> problems" - at a price. Heck: we don't run complicated RAC/ASM setups,
> so there M-U-S-T be a problem somewhere, right? Just like the security
> auditors who come in every 6 months and found nothing "broken" in the
> last 4 years.
> Ah well, Skynet can be fun! ;-)

There are quite a few unscrupulous consultants around. Pushing for RAC/ASM in every situation is probably the best warning sign. I love asking consultants for references. If I don't get a number of their clients, I know that there is a problem. As for Skynet, I like that chick that was playing T3. Keeping a face like that must be hard.

Received on Wed May 02 2012 - 16:53:18 CDT

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