Jonathan Lewis "Basic Cost Based Optimization"
Thursday, July 25, 2013 from 1:00 PM to 2:30 PM (BST)
Basic Cost Based Optimization
Webinar: I’ll be doing a one-hour paid webinar on Basic Cost Based Optimisation. The format will be similar to the free webinars, with some time after the hour for some questions; and I’ll follow up any unanswered questions on the blog. The charge will be $75, which includes access for 30 days after the recording is posted, and I’ll be speaking at 1:00 pm BST (7:00 AM US Central Time) and 6:00 pm BST (12:00 PM US Central).
Abstract: The webinar is for those who have no idea about how the optimizer manages to choose an execution plan and why it can choose the wrong one. In it we will examine a simple data set to highlight just three critical aspects of query optimisation in Oracle:
1 The work done acquiring data is dependent on the volume of the data, the location of the data, and the caching of the data.
2 The Cost Based Optimizer bases its cost calculation on its perception of the volume (cardinality) and location (clustering) of the data – and this dictates its choice of whether or not to use an index to access data, and which index to use.
3 The optimizer’s model is flawed in several critical ways, which leads to poor correlation between the calculated cost of a plan and the resources used executing that plan.
The more we come to recognise the flaws in the model, the easier it becomes to understand why the optimizer had chosen the wrong path.
Speak-Tech is Minnesota-based and has organized webinars and seminars featuring the world’s leading Oracle experts for over 12 years.
Speak-Tech has organized over 100 training events for experts such as Jonathan Lewis, Tom Kyte, Cary Millsap, Tim Gorman, Gaja Krishna Vaidyanatha and David Kurtz, considered to be some of the world’s leading experts in Oracle Performance Tuning; Syed Jaffar Hussain, Oracle ACE Director who was awarded the Oracle Excellence Award for Technologist of the Year: DBA, 2011; Steven Feuerstein, considered to the world's leading expert in PL/SQL, Jim Czuprysnski and Matt Hart, all leading experts in their Oracle specialties.