Today we are witnessing an exponential growth of information accumulated within universities, corporations, and government organizations. Autonomous repositories that store different types of digital data in multiple formats are becoming available for use on the fast-evolving global information systems infrastructure. More concretely, with the World Wide Web and related internetworking technologies, there has been an explosion in the types, availability, and volume of data accessible to a global information system. However, this information overload makes it nearly impossible for users to be aware of the locations, organization or structures, query languages, and semantics of the information in various repositories. Available browsing and navigation tools assist users in locating information resources on the Internet. However, there is a real need to complement current browsing and keyword-based techniques with concept-based approaches. An important next step should be to support queries that do not contain information describing location or manipulation of relevant resources. Ontology-Based Query Processing for Global Information Systems describes an initiative for enhancing query processing in a global information system. The following are some of the relevant features: Providing semantic descriptions of data repositories using ontologies; Dealing with different vocabularies so that users are not forced to use a common one; Defining a strategy that permits the incremental enrichment of answers by visiting new ontologies; Managing imprecise answers and estimations of the incurred loss of information. In summary, technologies such as information brokerage, domain ontologies, andestimation of imprecision in answers based on vocabulary heterogeneity have been synthesized with Internet computing, representing an advance in developing semantics-based information access on the Web. Theoretical results are complemented by the presentation of a prototype that implements the main ideas presented in this book. Ontology-Based Query Processing for Global Information Systems is suitable as a secondary text for a graduate-level course, and as a reference for researchers and practitioners in industry.

Today we are witnessing an exponential growth of information accumulated within universities, corporations, and government organizations. Autonomous repositories that store different types of digital data in multiple formats are becoming available for use on the fast-evolving global information systems infrastructure. More concretely, with the World Wide Web and related internetworking technologies, there has been an explosion in the types, availability, and volume of data accessible to a global information system. However, this information overload makes it nearly impossible for users to be aware of the locations, organization or structures, query languages, and semantics of the information in various repositories. Available browsing and navigation tools assist users in locating information resources on the Internet. However, there is a real need to complement current browsing and keyword-based techniques with concept-based approaches. An important next step should be to support queries that do not contain information describing location or manipulation of relevant resources.Ontology-Based Query Processing for Global Information Systems describes an initiative for enhancing query processing in a global information system. The following are some of the relevant features: * Providing semantic descriptions of data repositories using ontologies; * Dealing with different vocabularies so that users are not forced to use a common one; * Defining a strategy that permits the incremental enrichment of answers by visiting new ontologies; * Managing imprecise answers and estimations of the incurred loss of information. In summary, technologies such as information brokerage, domain ontologies, and estimation of imprecision in answers based on vocabulary heterogeneity have been synthesized with Internet computing, representing an advance in developing semantics-based information access on the Web. Theoretical results are complemented by the presentation of a prototype that implements the main ideas presented in this book. Ontology-Based Query Processing for Global Information Systems is suitable as a secondary text for a graduate-level course, and as a reference for researchers and practitioners in industry.

This book constitutes the thoroughly refereed joint post-proceedings of nine workshops held as part of the 10th International Conference on Extending Database Technology, EDBT 2006, held in Munich, Germany in March 2006.

The 70 revised full papers presented were selected from numerous submissions during two rounds of reviewing and revision. In accordance with the topical focus of the respective workshops, the papers are organized in sections on database technology in general (EDBT PhD Workshop), database technologies for handling XML information on the Web (DataX 2006), inconsistency and incompleteness in databases (IIDB 2006), information integration in healthcare (IIHA 2006), semantics of sequence and time dependent data (ICSNW 2006), query languages and query processing (QLQP 2006), pervasive information management (PIM 2006), pattern representation and management (PaRMa 2006), and reactivity on the Web.