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November 16

14:00 - 15:00 UTC    Start Times Around the World


Why are tables missing from the plan? An introduction to optimizer transformations
When you submit a SQL query to the database, it's up to the optimizer to figure out how to run it.

In this process the optimizer will often change the query to help it run faster. This can result in surprising execution plans.

Join this session to understand why these transformations happen, get an overview of what they are, and steps you can take to ensure optimal SQL.

Your Experts

Chris Saxon
Chris Saxon, Oracle Developer Advocate for SQL    
Chris Saxon is an Oracle Developer Advocate and quizmaster on Dev Gym. His job is to help you get the best out of the Oracle Database and have fun with SQL! He's also part of the answer team on Ask TOM and creates YouTube videos at The Magic of SQL channel.
Nigel Bayliss
Nigel Bayliss, Optimizer Product Manager    
I'm the product manager for the Oracle Optimizer. I started out as an Oracle DBA and application developer in 1988, gradually migrating to the field of consulting, specializing in database design and performance management. I joined Oracle Consulting in 1996 where I concentrated on delivering performance-critical, very large database applications. Since then, I've been involved in a wide variety of different roles including development, benchmarking and pre-sales (with a particular emphasis on Oracle Exadata). I am part of the Oracle Data Warehouse Product Management team.