| TR#: | CS0421 |
| Class: | CS |
| Title: | The Relational Algebric Operator NOT |
| Authors: | Yoav Raz |
| CS0421.pdf | |
| Abstract: | Some Relational Algebra (RA) operations give the exact meaning of Natural Language (NL) constructs when both Entity-sets and Relationship-sets are represented as relations (e.g. relativization and the natural-join, coordination and the union and intersection, universal-quantifiers and setcomparison, and the generalized-division, restriction and the selection and theta-join). The proposed NOT (COMPLEMENT) operator enables to express NL negation as a single operation in "closed world" databases. It can replace the subtraction, which does not have a direct linguistic analog, and is useful being implemented in an environment which supports NL or NL-like queries using RA. |
| Copyright | The above paper is copyright by the Technion, Author(s), or others. Please contact the author(s) for more information |
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