Keyword Queries over the Deep Web

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9974)


The Deep Web is constituted by data that are accessible through Web pages, but not indexable by search engines as they are returned in dynamic pages. In this paper we propose a conceptual framework for answering keyword queries on Deep Web sources represented as relational tables with so-called access limitations. We formalize the notion of optimal answer and characterize queries for which an answer can be found.


Keyword query Access pattern Deep web 



A. Calì acknowledges support from the EPSRC grant EP/E010865/1 (“LIQUID”) and from the EU COST Action IC1302 (“KEYSTONE”). D. Martinenghi acknowledges support from the EC’s FP7 “CUbRIK” and “SmartH2O” projects, and the FESR project “Proactive”.


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Copyright information

© Springer International Publishing AG 2016

Authors and Affiliations

  1. 1.Birkbeck, University of LondonLondonUK
  2. 2.Politecnico di MilanoMilanoItaly
  3. 3.Università Roma TreRomaItaly

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