Chris Saxon speaking at Tech Exeter Conference

Chris Saxon


Why Isn't My Query Using an Index?: An Introduction to SQL Performance

“Why isn’t my query using an index?” is a common question people have when tuning SQL.

This talk explores the factors that influence the optimizer’s decision behind this question. It introduces the concepts of blocks and the clustering factor. It discusses how these affect the optimizer's calculations. It goes on to show how these concepts work in practice using real SQL queries.

This session is intended for developers who want to learn how the optimizer works and how to make their SQL run quickly!


Chris Saxon is an Oracle Developer Advocate for SQL. He's here to help you get the best out of the Oracle Database and have fun with SQL!

To help you with this he blogs at All Things SQL and creates videos combining SQL and magic on The Magic of SQL.

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