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Codd's theorem

Codd's theorem states that relational algebra and the domain-independent relational calculus queries, two well-known foundational query languages for the relational model, are precisely equivalent in expressive power. That is, a database query can be formulated in one language if and only if it can be expressed in the other.

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Codd's theorem

Nodes13
Edges12
Triples13
Avg. degree1.85
Density0.153846
Components1

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Codd's theorem

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related to External links · 13
Codd's theorem → Archived, August, Computation, Database Theory, DBAI Group, Institute, Logic, March, PDF, Pichler, Reinhard, Retrieved August, TU Wien

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Important terminology

relational query theorem codd's database calculus languages algebra queries expressive power equivalent domains tuples sql codd logic completeness data two

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Codd's theoremrelated to External linksPichler0.60section
Codd's theoremrelated to External linksReinhard0.60section
Codd's theoremrelated to External linksMarch0.60section
Codd's theoremrelated to External linksDatabase Theory0.60section
Codd's theoremrelated to External linksPDF0.60section
Codd's theoremrelated to External linksInstitute0.60section
Codd's theoremrelated to External linksLogic0.60section
Codd's theoremrelated to External linksComputation0.60section
Codd's theoremrelated to External linksDBAI Group0.60section
Codd's theoremrelated to External linksTU Wien0.60section
Codd's theoremrelated to External linksArchived0.60section
Codd's theoremrelated to External linksAugust0.60section

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