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IADIS International Conference WWW/Internet 2010Figure 8. XLPath processor console.‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ XLPath Query ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐/d‐ba_BankingActivitiesDomain::HL::arc‐source::arc(link:definitionArc)/LL::linked::locator()[attribute(label)='TotalBankingActivities']/LL::linked::remote()/HL::arc‐source::arc(link:definitionArc)/HL::arc‐source::remote(d‐ba_TotalBankingActivitiesSubjectBIA)‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ XLPath Result ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐Step (1): /d‐ba_BankingActivitiesDomain::HL::arc‐source::arc(link:definitionArc)Locators = {}Arcs = {definition: BankingActivitiesDomain to TotalBankingActivities}Resources = {}Remotes = {}Step (2): /LL::linked::locator()[attribute(label)='TotalBankingActivities']Locators = {TotalBankingActivities}Arcs = {}Resources = {}Remotes = {}Step (3): /LL::linked::remote()Locators = {}Arcs = {}Resources = {}Remotes = {TotalBankingActivities}Step (4): /HL::arc‐source::arc(link:definitionArc)Locators = {}Arcs = {definition: TotalBankingActivities to TotalBankingActivitiesSubjectBIA, definition: TotalBankingActivities toTotalBankingActivitiesSubjectSTAAlternative, definition: TotalBankingActivities to TotalBankingActivitiesSubjectAMA}Resources = {}Remotes = {}Step (5): /HL::arc‐source::remote(d‐ba_TotalBankingActivitiesSubjectBIA)Locators = {}Arcs = {}Resources = {}Remotes = {TotalBankingActivitiesSubjectBIA}Figure 9. XLPath processor exit.May and Malheiro [2001 and 2002] propose an extension for the namespace xlink, dbxlink, whichenables links behavior specification in the moment of the query. Through the inclusion of namespacedbxlink, it is possible to choose how the linkbase elements are added to the original XML document.However, to do so, the XML document must be changed, including at least, the standard settingdbxlink:transparent. This is not very practical in real applications and it is not applicable in documents whoserelationship semantic is important. Because of this semantic in the linkbases, what is expected is the recoveryof the meanings without changing the documents. May et al. [2008] propose an implementation to performqueries in XML based on dbxlink. The links are not seen as explicit connections, in which the users must beaware of the links and explicitly cross them in their queries. This proposal extends the XML native data basesystem eXist [eXist, 2009]. Different from XLPath, which proposes itself to be a language for navigation andquery to XML documents interconnected by XLink, this solution is included in the category of XML database system. Besides, the XLPath proposal is based on following the links explicitly when consulting anddeclaring them explicitly in its operators.97