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RE: Daramtically improve BCHR with a single statement

From: mantfield <mantfield_at_CONNEXUS.NET.AU>
Date: Sun, 12 Jan 2003 19:08:43 -0800
Message-ID: <F001.0052D624.20030112190843@fatcity.com>


To add an example of what Anjo, Morgens and everyone else is talking about, here is a perfect illustration of why focusing on BCHR is like concentrating intensely on how fast your tyres rotate in a Tour de France, instead of looking of where you are going (probably a lot more useful). Another example:
If I raced (100M sprint) against Maurice Green, and he went off in the wrong direction, despite the fact that he is so much faster than me (duh !) , I could lightly jog (as if I have anything else to offer) the 100M in the right direction and beat him. Well, focusing on BCHR alone is like going at full tilt with no direction.
Also, I have realized that cars have been around for > 100 years now, so why exactly would I want to sprint again ? :-)

Check out this example:

run any number of scripts to look at BCHR. Then run the following anonymous PL/SQL block:

declare
  jackass number;
begin
 for jackass in 1..10000000 loop

    execute immediate 'select count (*) from solvit.solvit_lic ' ; -- replace this table with any single row table you like.  end loop;
end;
/

Check your BCHR again. Wow, amazing ! How much better your BCHR looks now. This must be magic. If you would like to purchase other such tools, please feel free to drop me a line, I could also sell you a large iceberg, which would end your personal water restriction problems.

Another advantage to the above code is that it eliminates idle capacity from my CPU's (I paid for the thing, it should be put to work, right ? ) as my laptop has been at 100% CPU utilization for the last 8 minutes as I let this piece of crap run before I killed it (Oracle 9 on XP with 512 MB RAM [SGA 120 MB], with a bunch of other starved stuff running concurrently).

Reduction of logical I/O : Now THERE is the holy grail worth pursuing ! I am sure we could have a VERY interesting discussion on that one !

Feel free to use the above example to prove for once and for all that concetration on tuning BCHR alone is a fruitless exercise.

Regards :

Ferenc Mantfeld

-----Original Message-----

From:	Rachel Carmichael [SMTP:wisernet100_at_yahoo.com]
Sent:	Monday, January 13, 2003 11:24 AM
To:	Multiple recipients of list ORACLE-L
Subject:	Re: BCHR Tuning

and those people "sell a tuning tool".... hm, I hadn't noticed any selling going on here. Or perhaps it's been subliminal?


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Received on Sun Jan 12 2003 - 21:08:43 CST

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