In March I’ll be speaking at the following two events.
|2009-03-10 15:30-16:30||Hotsos Symposium, Dallas (USA)||Bloom Filters|
|2009-03-18 16:00-16:45||SOUG-Tagung, Baden-Dättwil (CH)||SQL Plan Baselines|
The abstracts of the presentations are the following:
- Bloom Filters: A bloom filter is a data structure used to support membership queries. Simply put, a bloom filter is used to test whether an element is a member of a given set or not. Since Oracle Database 10g Release 2, bloom filters are used in various situations. Unfortunately, no information about their usage is available in Oracle documentation.
The aim of this presentation is to explain not only what bloom filters are, but also, and foremost, to describe how the database engine makes use of them. Specifically, it explains how the database engine uses bloom filters to reduce data communication between slave processes in parallel joins and to implement join-filter pruning.
- SQL Plan Baselines: A SQL plan baseline is an object associated with a SQL statement that is designed to influence the query optimizer while it generates execution plans. As of Oracle Database 11g, SQL plan baselines substitute stored outlines. Actually, they can be considered an enhanced version of stored outlines.
The aim of this presentation is to explain what SQL plan baselines are, how to create and manage them, and when to use them.