Processing keyword queries under access limitations

The Deep Web is constituted by data accessible through web pages, but not readily indexable by search engines, as they are returned in dynamic pages. In this paper we propose a framework for accessing Deep Web sources, represented as relational tables with so-called access limitations, with keyword-based queries. We formalize the notion of optimal answer and investigate methods for query processing. We also outline the main ideas of our implementation of a prototype system for Deep Web keyword search