Querying the Deep Web: Back to the Foundations
نویسندگان
چکیده
The Deep Web is the large corpus of data accessible on the Web through forms and presented in dynamically-generated pages, but not indexable as static pages, and therefore invisible to search engines. Deep Web data are usually modelled as relations with so-called access limitations, that is, they can be queried only by selecting certain attributes. In this paper we give some fundamental complexity results on the problem of processing conjunctive (select-project-join) queries on relational data with access limitations.
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