论文标题
冲流器：一种纯粹的定期方法，用于非规范的核心跨度
Refl-Spanners: A Purely Regular Approach to Non-Regular Core Spanners
论文作者
论文摘要
常规跨度（以VSet-Automata为特征）在联合，加入和投影的代数操作下关闭，并具有理想的算法属性。 The core spanners (introduced by Fagin, Kimelfeld, Reiss, and Vansummeren (PODS 2013, JACM 2015) as a formalisation of the core functionality of the query language AQL used in IBM's SystemT) additionally need string-equality selections and it has been shown by Freydenberger and Holldack (ICDT 2016, Theory of Computing Systems 2018) that this leads to high complexity and even静态分析和查询评估中典型问题的不确定性。我们提出了一种替代方法来进行核心跨越：通过将弦绳 - 平等选择直接合并到代表常规扳手的常规语言中（而不是将其视为基础的代数操作，我们在表格上提取的表格上提取的代数操作），我们获得了核心跨度的片段，同时又具有较弱的表达范围的核心范围，既然范围均等范围，又有较弱的核心范围，既有核心范围的范围，又有众多的范围覆盖了范围的范围。在静态分析和查询评估中，典型问题具有更好的上层复杂性范围。
The regular spanners (characterised by vset-automata) are closed under the algebraic operations of union, join and projection, and have desirable algorithmic properties. The core spanners (introduced by Fagin, Kimelfeld, Reiss, and Vansummeren (PODS 2013, JACM 2015) as a formalisation of the core functionality of the query language AQL used in IBM's SystemT) additionally need string-equality selections and it has been shown by Freydenberger and Holldack (ICDT 2016, Theory of Computing Systems 2018) that this leads to high complexity and even undecidability of the typical problems in static analysis and query evaluation. We propose an alternative approach to core spanners: by incorporating the string-equality selections directly into the regular language that represents the underlying regular spanner (instead of treating it as an algebraic operation on the table extracted by the regular spanner), we obtain a fragment of core spanners that, while having slightly weaker expressive power than the full class of core spanners, arguably still covers the intuitive applications of string-equality selections for information extraction and has much better upper complexity bounds of the typical problems in static analysis and query evaluation.
