A logic programming view of CLP
ICLP'93 Proceedings of the tenth international conference on logic programming on Logic programming
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
Information integration using logical views
Theoretical Computer Science - Special issue on the 6th International Conference on Database Theory—ICDT '97
An algorithm for answering queries efficiently using views
ADC '01 Proceedings of the 12th Australasian database conference
Rewriting general conjunctive queries using views
ADC '02 Proceedings of the 13th Australasian database conference - Volume 5
ICDE '96 Proceedings of the Twelfth International Conference on Data Engineering
A Scalable Algorithm for Answering Queries Using Views
VLDB '00 Proceedings of the 26th International Conference on Very Large Data Bases
Querying Heterogeneous Information Sources Using Source Descriptions
VLDB '96 Proceedings of the 22th International Conference on Very Large Data Bases
Optimizing Queries in Extended Relational Databases
DEXA '00 Proceedings of the 11th International Conference on Database and Expert Systems Applications
Query Transformation for PSJ-Queries
VLDB '87 Proceedings of the 13th International Conference on Very Large Data Bases
Computing queries from derived relations
VLDB '85 Proceedings of the 11th international conference on Very Large Data Bases - Volume 11
Abduction of linear arithmetic constraints
ICLP'05 Proceedings of the 21st international conference on Logic Programming
Heyting domains for constraint abduction
AI'06 Proceedings of the 19th Australian joint conference on Artificial Intelligence: advances in Artificial Intelligence
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The problem of finding contained rewritings of queries using views is of great importance in mediated data integration systems. In this paper, we first present a general approach for finding contained rewritings of unions of conjunctive queries with arbitrary built-in predicates. Our approach is based on an improved method for testing conjunctive query containment in this context. Although conceptually simple, our approach generalizes previous methods for finding contained rewritings of conjunctive queries and is more powerful in the sense that many rewritings that can not be found using existing methods can be found by our approach. Furthermore, nullity-generating dependencies over the base relations can be easily handled. We then present a simplified approach which is less complete, but is much faster than the general approach, and it still finds maximum rewritings in several special cases. Our approaches compare favorably with existing methods.