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Cost Based Optimizer - Common Misconceptions and Issues - 10g and Above (Doc ID 754931.1)

Last updated on AUGUST 04, 2018

Applies to:

Oracle Database - Enterprise Edition - Version and later
Information in this document applies to any platform.


This short article is intended to dispel a few myths about the cost based optimizer (referred to as the CBO from here on) and to highlight common mistakes and problem areas.

For a detailed description of the CBO see <Document:10626.1> which defines in detail some of the terms used in the article.

Also refer to:

Oracle� Database Performance Tuning Guide
11g Release 1 (11.1)
Part Number B28274-02
Chapter 11 The Query Optimizer


Oracle� Database Performance Tuning Guide
10g Release 2 (10.2)
Part Number B14211-03
Chapter 13 The Query Optimizer


This article is designed to give a basic understanding of the CBO.


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