Re: Convert SAP Oracle Database to IBM DB2 Database??

From: DA Morgan <>
Date: Fri, 08 Feb 2008 10:22:01 -0800
Message-ID: <>

Serge Rielau wrote:

> Can't comment on the other points as I don't know their meaning in the
> context.

ask <g>

> Are logs compressed?
> What about the pages in the buffer pool? We found
> that the effective doubling in bufferpool has significant impact on
> either cost of the system (reduced main memory requirements) or
> performance (better hit ratio).

As I don't know if I know something I shouldn't talk about I am going to avoid too much here. If Mark wants to answer I will leave that to him.

I find better compression and far better relative performance using Oracle's solution. The thing that I think Mark's team has nailed is when to perform the compression.

Consider this ... you have a new, empty, table. You insert one row. What are you going to compress? Insert a second row. What are you going to compress? Fill the block. Ask the question again.

No matter how you do it, to get back to the original point of the thread, it is a lousy reason to consider changing the back-end from product A to product B given what I've seen of both.

Daniel A. Morgan
Oracle Ace Director & Instructor
University of Washington (replace x with u to respond)
Puget Sound Oracle Users Group
Received on Fri Feb 08 2008 - 12:22:01 CST

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