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IADIS International Conference WWW/Internet 2010XLPATH: A XML LINKING PATH LANGUAGEPaulo Caetano da Silva*, Marcelo Mendonça dos Santos** and Valéria Cesário Times***Federal University of Pernambuco - Center for Informatics, PO BOX 7851, Brazil**Área 1 Science and Technology Faculty, Salvador, BrazilABSTRACTXLink are XML elements used for describing relationships and semantic information contained in valid XML documents.Thus, the structure of XLink can be navigated and their components (arcs, locators, resources and title) can be retrievedthrough a path language, like XPath. However, it was not specified to retrieve information from specific elements ofXlink, which can contain semantic information. This paper proposes XLPath, a path language turned to navigation onXLink, which allows performing queries on the elements that compose the links between XML documents. Aiming todemonstrate the use of XLPath, a processor prototype for this language was developed, which was evaluated in a casestudy based on XBRL documents, since XBRL is a technology that makes extensive use of XLink.KEYWORDSXLPath, XLink, Navigational Language, XML.1. INTRODUCTIONCurrent software applications usually have to deal with multiple data sources and data formats. In order tominimize this problem, XML has been adopted as a way to integrate data in a standard format. As a result ofthe increasing need of data integration and data exchange, XML documents are turning into very huge andrather interlinked files. Often, these documents have complex link networks pointing to all kinds ofresources. These resources should be used only combined with the XML document, since their semantics aredefined by the link networks. The XML Linking Language (XLink) [XLink, 2001] is used to describerelationships among resources included in XML documents and referenced by links. By the use of XLink, itis possible to create association rules among the link resources, as well as to define the semantics needed fortraversing a given link according to the specific meaning of this relationship. Processing documents with linknetworks has become a challenging task, because query languages usually do not support link traversingtechniques.One of the mechanisms used on data structures based on XML are the extended links provided by XLink.The extended links allow the establishment of more complex link structures, capable of relating an arbitrarynumber of resources [Lowe et.al, 2001]. An extended link basically consists of an XML element that containsother elements, where a namespace [Namespace, 2009] is used for declaring attributes specified by XLink,assigning to these sub-elements functionalities. Due to the functionalities offered by these mechanisms, insome situations the extended links have been used to represent the data semantic, modeling relationshipsbetween elements structured on XML or on XML Schema [Schema, 2004]. An example of how the datasemantic is represented on XLink is XBRL (eXtensible Business Reporting Language) [XBRL, 2003], aninternational standard for represent and publish financial reports that uses extended links for modelingfinancial conceptsHowever, despite of the functionalities provided by XLink, the maintenance and manipulation ofstructures that are based on extended links becomes a costly and inefficient task when a solution to automatethe navigation through these interconnected data structures is not available, making difficult the execution ofdata retrievals from the extended links. In this scenario, a process that demands the identification of remoteinformation, from an extended link, implies in a need of users performing a detailed analysis of the XMLdocument structure, “navigating” visually through the references established by the links until they reach thedesired information. Obviously, as the volume of data stored in the database increases, this navigation task89