On the relationship between description logic and predicate logic queries
On the relationship between description logic and predicate logic queries
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DOI：
10.1145/191246.191283
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发表时间：
1994-11
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影响因子：
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通讯作者：
Alexander Borgida
中科院分区：
文献类型：
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作者：
Alexander Borgida
描述语言形成了近年来开发的几个以对象为中心的知识库管理系统的基础，包括工业应用中的知识库管理系统。DL最初用于概念建模（定义视图），现在越来越多地用作检索信息的查询语言。本文，针对一般观众，包括数据库研究人员，认为表达能力的DL和基于谓词演算的查询语言之间的关系。我们表明，目前在文献中考虑使用构造器建立的所有描述可以表示为公式的一阶谓词演算（FOPC）最多有三个变量符号，虽然我们必须允许数字量词和无穷析取，以处理一些特殊的构造器。相反，我们表明，所有的一阶查询（公式与一个自由变量）建立了一元和二元谓词使用最多三个变量可以表示为描述。我们的结论是展示查询，不能表示为DL概念，并简要反映的后果。
Description languages form the basis of several object-centered knowledge base management systems developed in recent years, including ones in industrial use. Originally used for conceptual modeling (to define views), DLs are seeing increased use as query languages for retrieving information. This paper, aimed at a general audience that includes database researchers, considers the relationship between the expressive power of DLs and that of query languages based on Predicate Calculus. We show that all descriptions built using constructors currently considered in the literature can be expressed as formulae of the First Order Predicate Calculus (FOPC) with at most three variable symbols, though we have to allow numeric quantifiers and infinitary disjunction in order to handle some special constructors. Conversely, we show that all first-order queries (formulae with one free variable) built up from unary and binary predicates using at most three variables can be expressed as descriptions. We conclude by exhibiting queries that cannot be expressed as DL concepts, and reflecting briefly on consequences.