Sara Cohen, Yaron Kanza, Yakov Kogan, Werner Nutt, Yehoshua Sagiv, Alexander Serebrenik
备注:
This is a preprint of an article accepted for publication in Journal of the American Society for Information Science and Technology @ copyright 2001 John Wiley & Sons, Inc
EquiX is a search language for XML that combines the power of querying with the simplicity of searching. Requirements for such languages are discussed and it is shown that EquiX meets the necessary criteria. Both a graph-based abstract syntax and a formal concrete syntax are presented for EquiX queries. In addition, the semantics is defined and an evaluation algorithm is presented. The evaluation algorithm is polynomial under combined complexity.
EquiX combines pattern matching, quantification and logical expressions to query both the data and meta-data of XML documents. The result of a query in EquiX is a set of XML documents. A DTD describing the result documents is derived automatically from the query.
The SPARQL2XQuery Interoperability Framework. Utilizing Schema Mapping, Schema Transformation and Query Translation to Integrate XML and the Semantic Web
Web of Data是一个开放的环境,由来自不同领域的大量相互链接的大型RDF数据集组成。在这种环境中,组织和公司采用利用语义Web(SW)技术的关联数据实践,以便发布他们的数据并提供SPARQL端点(即,基于SPARQL的搜索服务)。另一方面,当今Web中信息交换的主导标准是XML。SW和XML世界及其开发的基础设施基于不同的数据模型、语义和查询语言。因此,至关重要的是开发互操作性机制,允许Web of Data用户从他们自己的工作环境中使用SPARQL访问XML数据集。期望所有现有的遗留数据(例如,关系、XML等)将转换为软件数据。因此,将遗留数据发布为关联数据并在其上提供SPARQL端点已成为一个主要的研究挑战。在这个方向上,我们引入了SPARQL 2XQuery框架,它创建了一个可互操作的环境,SPARQL查询自动转换为XQuery查询,以便在Web上访问XML数据。SPARQL 2XQuery框架为OWL-RDF/S到XML Schema映射的表达提供了一个映射模型,也为SPARQL到XQuery的转换提供了一种方法。为此,我们的框架支持本体和XML模式之间的手动和自动映射规范。在自动映射规范场景中,SPARQL 2XQuery利用将XML模式转换为OWL本体的XS 2 OWL组件。最后,进行了大量的实验,以评估模式转换,映射生成,查询翻译和查询评估效率,使用真实和合成…
ELCA Evaluation for Keyword Search on Probabilistic XML Data
随着概率数据管理的发展和关键字查询的普及,如何支持概率XML数据的关键字查询成为必然的问题。对于确定性XML文档的关键字查询,ELCA(Exclusive Lowest Common Ancestor)语义允许根在ELCA上的更多相关片段作为结果出现,与其他关键字查询结果语义(如SLCA)相比,ELCA语义更受欢迎。在本文中,我们研究如何评估ELCA结果的关键字查询概率XML文档。在根据可能世界语义定义了概率ELCA语义后,我们提出了一种在不生成可能世界的情况下计算ELCA概率的方法。然后,我们开发了一个有效的基于堆栈的算法,可以找到所有的概率ELCA结果和他们的ELCA概率为一个给定的关键字查询的概率XML文档。最后,我们实验评估所提出的ELCA算法,并将其与SLCA对应的结果有效性,时间和空间效率,可扩展性方面进行比较。
XML query can be modeled by twig pattern query (TPQ) specifying predicates on XML nodes and XPath relationships satisfied between them. A lot of TPQ types have been proposed; this paper takes into account a TPQ model extended by a specification of output and non-output query nodes since it complies with the XQuery semantics and, in many cases, it leads to a more efficient query processing. In general, there are two approaches to process the TPQ: holistic joins and binary joins. Whereas the binary join approach builds a query plan as a tree of interconnected binary operators, the holistic join …
In the current context of Big Data, a multitude of new NoSQL solutions for storing, managing, and extracting information and patterns from semi-structured data have been proposed and implemented. These solutions were developed to relieve the issue of rigid data structures present in relational databases, by introducing semi-structured and flexible schema design. As current data generated by different sources and devices, especially from IoT sensors and actuators, use either XML or JSON format, depending on the application, database technologies that store and query semi-structured data in XML …
可扩展置标语言(XML)是从SGML派生出来的一种简单、非常灵活的文本格式。XML最初是为了应对大规模电子出版的挑战而设计的,现在它在Web和其他地方的各种数据交换中也发挥着越来越重要的作用。XML语言是努力提供XML文档地址部分的结果。为了支持这一主要目的,它变成了一种针对XML文档的查询语言。在本文中,我们提出了一个建议,在逻辑程序设计中实现的语言。为了达到这个目的,我们将通过一个逻辑程序来描述XML文档的表示。规则和事实可用于表示文档模式和XML文档本身。特别是,我们将介绍如何索引XML文档的逻辑程序:规则应该存储在主存储器中,但事实存储在辅助存储器中使用两种索引:一个为每个XML标签,和其他的每组终端项目。此外,我们还将研究如何通过XML语言对表示XML文档的逻辑程序进行查询。它发展了逻辑程序关于表达式的专门化。最后,我们还将解释如何将索引和逻辑程序的自顶向下评估结合起来。逻辑程序设计理论与实践(Theory and Practice of Logic Programming,TPLP)
Linked Open Data (LOD) has been proliferated over various domains, however, there are still lots of open data in various format other than RDF, a standard data description framework in LOD. These open data can also be connected to entities in LOD when they are associated with URIs. Document-centric XML data are such open data that are connected with entities in LOD as supplemental documents for these entities, and to convert these XML data into RDF requires various techniques such as information extraction, ontology design and ontology mapping with human prior knowledge. To utilize document-ce…
INRIA(法国国家信息与自动化研究所);LIFL (CNRS UMR8022)(里尔基础信息实验室(法国国家科学研究中心 UMR8022));University of Lille(里尔大学);Institute of Computer Science(计算机科学研究所);University of Wrocław(弗罗茨瓦夫大学)
With the emergence of XML as de facto format for storing and exchanging information over the Internet, the search for ever more innovative and effective techniques for their querying is a major and current concern of the XML database community. Several studies carried out to help solve this problem are mostly oriented towards the evaluation of so-called exact queries which, unfortunately, are likely (especially in the case of semi-structured documents) to yield abundant results (in the case of vague queries) or empty results (in the case of very precise queries). From the observation that user…
In the XML community, exact queries allow users to specify exactly what they want to check and/or retrieve in an XML document. When they are applied to a semi-structured document or to a document with an overly complex model, the lack or the ignorance of the explicit document model (DTD-Document Type Definition, Schema, etc.) increases the risk of ob-taining an empty result set when the query is too specific, or, too large result set when it is too vague (e.g. it contains wildcards such as "*"). The reason is that in both cases, users write queries according to the document model they have in …
Technical University of Munich(慕尼黑工业大学);Univ. Artois, CNRS, UMR 8188, Centre de Recherche en Informatique de Lens (CRIL)(阿图瓦大学,法国国家科学研究中心,联合研究实验室8188,伦斯信息中心);University of Warsaw(华沙大学);CRIStAL, Université de Lille, INRIA(CRIStAL实验室,里尔大学,法国国家数字科学与创新研究所)