A Semantical Notion of Relevance in Speciications of Database Updates and Its Computational Counterpart
نویسندگان
چکیده
Using the situation calculus as underlying formalism for specifying database updates as proposed by Raymond Reiter, a semantical notion of relevance of entries in tables to other entries is introduced. Also a semantical notion of relevant action is provided. Some properties of these semantical notions are investigated. In particular, they are compared with syntactical deenitions of relevance that can be used for answering historical queries in databases. Other uses of the semantical concepts of relevance and extensions are discussed.
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