An extended Relational Algebra on Abstract Objects for summarizing answers to queries

• Autorzy: Demolombe R.
• Języki publikacji: EN

Abstrakty

EN

Answers to queries in terms of abstract objects are defined in the logical framework of first order predicate calculus. A partial algebraic characterisation of the supremum and of the infimum of abstract answers is given in an extended Relational Algebra of the Cylindric Algebra kind. Then, the form of queries is restricted in order to be able to compute answers without the cylindrification operator. For these restricted queries we give a technique to compute an upper bound and a lower bound of abstract answers using only the operators of the standard Relational Algebra.

Słowa kluczowe

EN

relational algebra; cylindric algebras; first-order logic; abstraction

• Wydawca: IOS Press
• Czasopismo: Fundamenta Informaticae
• Rocznik: 2003
• Tom: Vol. 57, nr 1
• Strony: 1--15
• Opis fizyczny: Bibliogr. 11 poz.

Twórcy

autor

Demolombe R.

• ONERA Toulouse, France,

Bibliografia

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