Sommario
Relational Algebra
Relational Query Languages
Formal Relational Query Languages
Preliminaries
Example Instances
Relational Algebra
Projection
Selection
Union, Intersection, Set-Difference
Cross-Product
Joins
Joins
Division
Examples of Division A/B
Expressing A/B Using Basic Operators
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Exercise
Exercise (cont.nd)
Exercise (cont.nd)
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