Since the introduction of the Cost Based Optimizer (CBO) in Oracle 7.0, people have been both fascinated and terrified by it and the statistics that feed it. There has long been a belief that a degree in witchcraft or black magic is required to successfully work with the CBO. Some people feel this shroud of mystery is caused in part by the lack of documentation or detailed examples about the Optimizer. In order to help remove this shroud and the black magic that surround the Optimizer, the development team responsible for it have started a blog. The blog postings will give in-depth descriptions of the technology behind the CBO, as well as practical advice like best practices for using the Optimizer. Their first blog post, Why are there more cursors in 11g for my query containing bind variables? went up on December 3rd and it discusses the controversial topic of Bind Peeking and how it has been enhanced in 11g. I recommend you check out their blog at http://optimizermagic.blogspot.com.

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Execution Plans, Optimizer, Oracle, Performance, Statistics, Troubleshooting