Re: Comparisons Oracle to Oracle

From: Arne Ortlinghaus <>
Date: Fri, 23 Oct 2009 08:34:39 +0200
Message-ID: <hbripv$nv2$>


yes, you are right. It is true that with the tests I make I can see only few aspects. Since I try to use the new initialization parameters if possible it is also important to get some feedback.
For example until Oracle 10 we needed the two parameters optimizer_index_cost_adj = 10
optimizer_index_caching = 99
in our database to have good performance. Until now the database underestimated always the benefits of indexes. In my tests until now it seems that Oracle 11 is predicting better without explicitly setting these parameters. But I have to make some further tests to be sure about that.

The results Charles has given in the email above are also interesting. In my eyes they show that there are no disadvantages moving to Oracle 11.

Our databases are a mixed type OLTP and Datawarehouse. Since we started with Oracle 8 we are used to try to simplify statements and to add indexes where possible. Surely every new version of Oracle gives new capabilities in executing complex queries better but possibly needs more overhead in processing simple statements. We will move to Oracle 11, but it depends a little bit on the actual results of our (subjective) tests when we will do this: in the following months or may be in half a year. Our problem is that with the same applications we have many small installations (one or two workplaces), where the database is on the pc of the user. We have many installations with 5 to 10 workplaces, and few important installations with 50 workplaces or more. The smallest databases have few GB of data, the biggest are still below 1 Tera Byte of data and all of them should work with the same set of tables/indexes without optimizing each database differently.

Arne Ortlinghaus Received on Fri Oct 23 2009 - 01:34:39 CDT

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