论文标题
在基于本体的数据访问中查询表达和验证
Query Expressibility and Verification in Ontology-Based Data Access
论文作者
论文摘要
在基于本体的数据访问中，使用本体和映射集成了多个数据源。在实践中，这通常是通过引导过程来实现的，即，本体和映射首先旨在仅支持来源上最重要的查询，然后逐渐扩展以启用其他查询。在本文中，我们研究了支持这种方法的两个推理问题。表达性问题询问给定的源查询$ q_s $是否可以作为目标查询（即，在本体论的词汇量上）表达，并且验证问题提出了询问，还给出了候选目标查询$ q_t $，是否$ q_t $表示$ q_s $。我们将（u）CQ视为源和目标查询和GAV映射，表明两个问题均为$π^p_2 $ -complete在植根源查询时，EL和Elhi之间的DL-Lite中的conexplete-Complete，以及无限制源源查询的2Exptime-Complete。
In ontology-based data access, multiple data sources are integrated using an ontology and mappings. In practice, this is often achieved by a bootstrapping process, that is, the ontology and mappings are first designed to support only the most important queries over the sources and then gradually extended to enable additional queries. In this paper, we study two reasoning problems that support such an approach. The expressibility problem asks whether a given source query $q_s$ is expressible as a target query (that is, over the ontology's vocabulary) and the verification problem asks, additionally given a candidate target query $q_t$, whether $q_t$ expresses $q_s$. We consider (U)CQs as source and target queries and GAV mappings, showing that both problems are $Π^p_2$-complete in DL-Lite, coNExpTime-complete between EL and ELHI when source queries are rooted, and 2ExpTime-complete for unrestricted source queries.
