Foundations of logic programming; (2nd extended ed.)
Foundations of logic programming; (2nd extended ed.)
Managing semantic heterogeneity in databases: a theoretical prospective
PODS '97 Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Answering recursive queries using views
PODS '97 Proceedings of the sixteenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Complexity of answering queries using materialized views
PODS '98 Proceedings of the seventeenth ACM SIGACT-SIGMOD-SIGART symposium on Principles of database systems
Logical approaches to incomplete information: a survey
Logics for databases and information systems
Navigational plans for data integration
AAAI '99/IAAI '99 Proceedings of the sixteenth national conference on Artificial intelligence and the eleventh Innovative applications of artificial intelligence conference innovative applications of artificial intelligence
SIGMOD '00 Proceedings of the 2000 ACM SIGMOD international conference on Management of data
Foundations of Databases: The Logical Level
Foundations of Databases: The Logical Level
Logic-based techniques in data integration
Logic-based artificial intelligence
Query Folding with Inclusion Dependencies
ICDE '98 Proceedings of the Fourteenth International Conference on Data Engineering
ICDE '96 Proceedings of the Twelfth International Conference on Data Engineering
Information Integration Using Logical Views
ICDT '97 Proceedings of the 6th International Conference on Database Theory
Tableau Techniques for Querying Information Sources through Global Schemas
ICDT '99 Proceedings of the 7th International Conference on Database Theory
Answering queries using views: A survey
The VLDB Journal — The International Journal on Very Large Data Bases
View-Based Query Processing and Constraint Satisfaction
LICS '00 Proceedings of the 15th Annual IEEE Symposium on Logic in Computer Science
Answering Regular Path Queries Using Views
ICDE '00 Proceedings of the 16th International Conference on Data Engineering
Query Planning with Limited Source Capabilities
ICDE '00 Proceedings of the 16th International Conference on Data Engineering
Explicit Representation of Constrained Schema Mappings for Mediated Data Integration
DNIS '02 Proceedings of the Second International Workshop on Databases in Networked Information Systems
Source integration for data warehousing
Multidimensional databases
Integration of biological sources: current systems and challenges ahead
ACM SIGMOD Record
Logical foundations of peer-to-peer data integration
PODS '04 Proceedings of the twenty-third ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
Data integration: a logic-based perspective
AI Magazine - Special issue on semantic integration
Towards Ontology Generation from Tables
World Wide Web
Schema merging and mapping creation for relational sources
EDBT '08 Proceedings of the 11th international conference on Extending database technology: Advances in database technology
Ontology-driven geographic information integration: A survey of current approaches
Computers & Geosciences
Conceptual Modeling for Data Integration
Conceptual Modeling: Foundations and Applications
First-Order patterns for information integration
ICWE'05 Proceedings of the 5th international conference on Web Engineering
Consistent query answers in virtual data integration systems
Inconsistency Tolerance
Data integration targeting a drug related knowledge base
EDBT'06 Proceedings of the 2006 international conference on Current Trends in Database Technology
Integrating and exchanging XML data using ontologies
Journal on Data Semantics VI
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There are basically two approaches for designing a data integration system. In the global-as-view (GAV) approach, one maps the concepts in the global schema to views over the sources, whereas in the local-as-view (LAV) approach, one maps the sources into views over the global schema. The goal of this paper is to relate the two approaches with respect to their expressive power. The analysis is carried out in a relational database setting, where both the queries on the global schema, and the views in the mapping are conjunctive queries. We introduce the notion of query-preserving transformation, and query-reducibility between data integration systems, and we show that, when no integrity constraints are allowed in global schema, the LAV and the GAV approaches are incomparable. We then consider the addition of integrity constraints in the global schema, and present techniques for query-preserving transformations in both directions. Finally, we show that our results imply that we can always transform any system following the GLAV approach (a generalization of both LAV and GAV) into a query-preserving GAV system.