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

From: <>
Date: Fri, 8 Feb 2008 21:58:24 -0800 (PST)
Message-ID: <>

On Feb 9, 12:22 am, DA Morgan <> wrote:
> Mark Townsend wrote:
> >> The compression dictionary is part of the table's meta-data, thus it
> >> is cached.
> > At some stage this is going to hit a memory limit, as more data and more
> > tables are compressed.
> >  > If data values are highly localized, then having local
> >> dictionaries can be helpful.
> > That IS the crux of the matter. We think most data is indeed localized,
> > I would be surprised, and willing to discuss over a beer, if IBM thought
> > differently.
> > BTW - that is why random data generation does not show compression of
> > well in Oracle.
> The fact that it achieves as high a compression as it does is actually
> quite impressive which was the point of my demo.
> >>> 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.
> >> I don't think it is a lousy reason. It is an insufficient reason in
> >> isolation.
> > And interesting enough, the whole conversation has been largely
> > irrelevant. The real question to ask - given product A and product B,
> > under SAP, which database takes more space to store the same amount of
> > data ? Firstly uncompressed, and then compressed. The answer is freely
> > available to anyone with a SAP support contract.
> Though I still think that far less important to management than the size
> of the pool of potential employees that can manage that infrastructure
> not just today but 5+ years from now when the current crop of gray-hair
> no-hair DBAs hit retirement age.
> --
> Daniel A. Morgan
> Oracle Ace Director & Instructor
> University of Washington
> (replace x with u to respond)
> Puget Sound Oracle Users Hide quoted text -
> - Show quoted text -

My company is mingrating fromDB2 to Oracle for SAP because there are many morep eople who know Oracle than DB2. SAP was developed to be "database independent",but I read they provide libraries of their databse code
optimized for Oracle as well. Therearemany implementaions of SAP using Oracle. I doubut decision for choosing BD2 vs Oracle iseverbased on compression or one ortwo fetaures. Received on Fri Feb 08 2008 - 23:58:24 CST

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