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Gentle introduction to opimization

I was just asked to prepare a short, one-hour workshop/presentation about optimization on Oracle. As this topis is so huge, and everyone had already read something, I decided to concept this workshop as an overview of the concepts (starting with db design) and the tools available.
The .pdf version is thus a kind of checklist - have you read about all of these issues? Have you thought them out when designing your system?
I hope you will find at least one new thing there:-)
The PDF is available for download on my website download area.

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