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Description

Session ID: 286

Abstract:

One of the most common SQL Tuning problems is when the Oracle cost-based optimizer misestimates the expected number of rows that will be returned from an execution plan row source operation. This presentation delves into uncharted waters to help attendees understand strategies for dealing with cardinality misestimates.

Objective 1: Attendees will understand the role that cardinality estimates play in the CBO's costing process.

Objective 2: Attendees will be able to identify various situations that cause inaccurate cardinalities.

Objective 3: Attendees will have a better understanding of the various fixes that can be applied, and when to apply them.

Audience: In-Depth

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