CBO Series

This is the index to a series of articles about the cost-based optimizer that I wrote in 2015 for AllthingsOracle (part of redgate / Simpletalk). The intention in this series is to present the optimizer with far less formality than I did in the book (Cost Based Oracle – Fundamentals), talking through ideas, problems and solutions and only presenting some arithmetic to explain why a problem appears or why a solution works.

• Part 1 – The optimizer’s “thought processes” when considering a two-table join
• Part 2 – Steps we can take to understand the data and its patterns when the optimizer chooses “the wrong plan”
• Part 3 – Comparing the simplest cases of hash joins to nested loop joins
• Part 4 – Query blocks and the big picture
• Part 5 – Why the optimizer picks bad plans and how to help it (1)
• Part 6 – Why the optimizer picks bad plans and how to help it (2)

March 2016

The series has been translated into Chinese by James Su at this URL.