Table of Contents
Relational Query Optimization
Overview of Query Optimization
Highlights of System R Optimizer
Motivating Example
Alternative Plan 1 (No Indexes)
Alternative Plan 2 (With Indexes)
Cost Estimation
Statistics and Catalogs
Size Estimation and Reduction Factors
Result Size Estimation (cont’d)
Relational Algebra Equivalences
More Equivalences
Enumeration of Alternative Plans
Queries Over Multiple Relations
Enumeration of Left-Deep Plans
Enumeration of Plans (Contd.)
Example
Summary
State of the Art (partial snapshot)
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