Re: Using an index.

From: Sybrand Bakker <gooiditweg_at_nospam.demon.nl>
Date: Sat, 26 Apr 2003 06:53:23 +0200
Message-ID: <kv3kavckmasd00ladb541tlj6o1h144efo@4ax.com>

On 25 Apr 2003 15:43:25 -0700, pharfromhome_at_hotmail.com (Geomancer) wrote:

>>
>> If you're going to IOUG-A I'll try to find time
>> to explain what I did in my presentation on
>> CBO on Monday afternoon.
>
>Um, what you did was make the query run sub-optimally.
>
>Is configuring Oracle to make SQL run slower the topic of your IOUG
>presentation? (Heck, I do that all the time)
>
>Kidding aside, it's no great trick to make the CBO goof up, right?
>Most DBAs spend most of their time getting the CBO going, do a
>benchmark, and then set optimizer_goal=rule.
>
>Don't rule-out the rule-based optimizer! It rocks!

Evidently, this is stupid advice, given the fact that the rule based optimizer hasn't been updated since 1994 (know how long that is? NINE full years!! Where have you been?) and doesn't know about all the new access methods created since 1994. There are enough whitepapers one the web *demonstrating* the inability of the RBO, and also the RBO won't be in the next release of Oracle. But I guess you are running on 6.0.36 anyway, so you won't be afffected.

Sybrand Bakker, Senior Oracle DBA

To reply remove -verwijderdit from my e-mail address Received on Fri Apr 25 2003 - 23:53:23 CDT