Re: Tuning Oracle SQL

From: Patrick Elliott <pelliott_at_isd.net>
Date: 1996/12/18
Message-ID: <32b810f7.0@usamrid.isd.net>#1/1

I have had problems with cost based optimization and multiple unique indexes. Cost based appears to always use the primary key whether a hint is given or not. I had to use rules based optimization or first rows optimization (If there is no summarization) to get it to work. "Brian M. Biggs" <bbiggs_at_cincom.com> wrote:

>Mike Whaley wrote:
>>
>> This last guys has some good suggestions. I would add the following:
>>
>> 1) Remember to do an "ANALYZE" on each table and index. There is a
>> stored procedure shipped with Oracle for this. The COST based optimizer
>> does not stand a chance without it.

>I'm still hearing conflicting reports about the usefulness of Oracle's
>cost-based optimizer. I've had Oracle people say that you're still
>better off sticking with the rule-based optimizer, even in Oracle 7.3.

>Any opinions (dumb question, I know)?

>Thanks,
>Brian

>--
>Brian M. Biggs mailto:bbiggs_at_cincom.com
>Cincom Systems, Inc. voice: (513) 677-7661
>http://www.cincom.com/
Received on Wed Dec 18 1996 - 00:00:00 CST