Table of Contents
Relational Algebra
Relational Query Languages
Formal Relational Query Languages
Preliminaries
Example Instances
Relational Algebra
Projection
Selection
Union, Intersection, Set-Difference
Cross-Product
Joins
Joins
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Relational Calculus
Relational Calculus
Tuple Relational Calculus
TRC Formulas
Free and Bound Variables
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Unsafe Queries, Expressive Power
Summary
Nested Relations
Nested Relational Algebra
Nesting and Unnesting
Extending Relational Operators
Nested Relations Summary
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