This paper is an introduction to the new 'performance schema' feature, which will be part of the upcoming MySQL 5.5 release. Covering in details every part of the performance schema would require much, much more than a simple article. The pace of this teaser is voluntarily fast, to have a quick overview of the new landscape, and help users already familiar with MySQL to understand by examples what the performance schema provides.

The release of MySQL 5.5 has brought several enhancements. While most of the coverage went, understandably, to the semi-synchronous replication, the enhancements of partitioning were neglected, and sometimes there was some degree of misunderstanding on their true meaning. With this article, we want to explain these cool enhancements, especially the parts that were not fully understood.