EquiX - A search and query language for XML

Journal of Intelligent Information Systems, 2009

Text search engines are inadequate for indexing and searching XML documents because they ignore metadata and aggregation structure implicit in the XML documents. On the other hand, the query languages supported by specialized XML search engines are very complex. In this paper, we present a simple yet flexible query language, and develop its semantics to enable intuitively appealing extraction of

Lecture Notes in Computer Science, 2003

Most query and transformation languages developed since the mid 90es for XML and semistructured data-e.g. XQuery [1], the precursors of XQuery [2], and XSLT [3]-build upon a path-oriented node selection: A node in a data item is specified in terms of a root-to-node path in the manner of the file selection languages of operating systems. Constructs inspired from the regular expression constructs * , +, ?, and "wildcards" give rise to a flexible node retrieval from incompletely specified data items. This paper further introduces into Xcerpt, a query and transformation language further developing an alternative approach to querying XML and semistructured data first introduced with the language UnQL [4]. A metaphor for this approach views queries as patterns, answers as data items matching the queries. Formally, an answer to a query is defined as a simulation [5] of an instance of the query in a data item.

XML is becoming prevalent in data presentation and data exchange on the internet. One important issue in the XML research community is how to query XML documents to extract and restructure information. Currently, XQuery based on XPath is the most promising standard. In this paper, we discuss limitations of XPath and XQuery, and propose a generalization of XPath called XTree that overcomes these limitations. Using XTree, multiple variable bindings can be instantiated in one expression; and XTree expressions, which represent a tree rather than a path, can be used in both the querying part and the result construction part of a query. Based on XTree, we develop an XTree query language, which is more compact and convenient to use than XQuery, and supports common query operations such as join, negation, grouping, and recursion in a direct way. We describe an algorithm that converts XTree query scripts to XQuery scripts. This algorithm provides not only a means of executing queries written in XTree query language but also highlights differences between the two query languages.

XML-Based Data Management and …, 2002

Computer Networks, 1999

An important application of XML is the interchange of electronic data (EDI) between multiple data sources on the Web. As XML data proliferates on the Web, applications will need to integrate and aggregate data from multiple source and clean and transform data to facilitate exchange. Data extraction, conversion, transformation, and integration are all well-understood database problems, and their solutions rely on a query language. We present a query language for XML, called XML-QL, which we argue is suitable for performing the above tasks. XML-QL is a declarative, 'relational complete' query language and is simple enough that it can be optimized. XML-QL can extract data from existing XML documents and construct new XML documents.

Web Information Systems and Technologies, 2006

We have observed an increase in document search needs in organizations. This increase in document search demand has required better efficiency on search software languages. The current technologies are using specific patterns to search documents. The most usual pattern, called XML, has been proposed by W3C and some languages (e.g. XQL, XML-QL etc.) were created to recover XML documents. The implementation of a XML query server, which abstracts the language used, has been an emerging necessity. This paper surveys technology used to develop a XML query server, called XQOM Schema, from the modelling to the implementation. In an organization setting, we have adopted new abstraction forms of searching for XML documents without the usage limitation established by a specific language. XQOM Schema may contribute to the creation of an universal document searching pattern in XML format.

1998

XML is a new standard that supports data exchange on the World-Wide Web. It is likely to become as important and as widely used as HTML.

Proceedings of the 29th …

XSEarch, a semantic search engine for XML, is presented. XSEarch has a simple query lan- guage, suitable for a naive user. It returns se- mantically related document fragments that satisfy the user's query. Query answers are ranked using extended information-retrieval ...

2000

In this paper, we describe the characteristics of two different query languages designed to query XML data: DSQL, a declarative SQL like language and XQuery, a procedural language that is fast becoming the defacto language for XML querying. We then describe the design of an experiment aimed at comparing the accuracy and efficiency of the query formulation process when using

Lecture Notes in Computer Science, 2005

In the past decade, researchers have combined deductive and object-oriented features to produce systems that are powerful and have excellent modeling capabilities. More recently, an XML query language XTree was proposed. Queries written in XTree are more compact, more convenient to write and easier to understand than queries written in XPath. In this paper, we introduce a novel XML query language XDO2 that extends XTree, with deductive features such as deductive rules and negation, and object-oriented features such as inheritance and methods. Our XDO2 language is more compact, and convenient to use than current query languages for XML such as XQuery and XPath because it is based on XTree, supports (recursive) deductive rules and the not-predicate. An XDO2 database example is given to motivate the usefulness of the language. The formal treatment of language syntax and semantics are presented in the appendices.