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Last week, Oracle Ace Director Jonathan Lewis held an Oracle Optimizer Workshop at dbi services Basel Area. I would like to share some of the key learnings of this really interesting exchange I experienced together with my colleagues.
In his workshop, Jonathan Lewis covered an impressive amount of Oracle optimizer know how: from the fundamentals of the Cost Based Optimizer (CBO) to the latest 11.2 Oracle Optimizer features. Useless to say that we were all amazed from Jonathan's expertise.

Jonathan provided an impressive insight into the Oracle Optimizer which really helped me to better grasp the decisions of the Cost Based Optimizer (CBO). Understanding how and why nested loops or hash joins are used is a black box if you are not aware of the underlying "maths". This kind of information cleary was a big added value of Jonathan's workshop. He also gave us lots of practical and very funny examples of his experience at customer sites.

As most of you know, Jonathan Lewis is a well known figure in the Oracle community and has also published several books (last publication in November 2011: Oracle Core: Apress, ISBN 978-1430239543). His blog really is a key Oracle resource (http://jonathanlewis.wordpress.com/) and he also contributes to several other blogs, newsgroups, forums, and Oracle User Group magazines.

Again, Jonathan, thanks a lot for your great workshop!
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