Since 1995, Christian Antognini has focused on understanding how the Oracle Database engine works. His main interests include logical and physical database design, the query optimizer and basically everything else related to application performance management. He is currently working as a senior principal consultant and trainer at Trivadis in Zürich, Switzerland. Christian is a proud member of the OakTable Network and an Oracle ACE Director. He is the author of Troubleshooting Oracle Performance (Apress, 2008/2014) and the co-author of Der Oracle DBA (Hanser, 2011/2016).