Query caching and optimization in distributed mediator systems
SIGMOD '96 Proceedings of the 1996 ACM SIGMOD international conference on Management of data
An adaptive query execution system for data integration
SIGMOD '99 Proceedings of the 1999 ACM SIGMOD international conference on Management of data
Capabilities-based query rewriting in mediator systems
DIS '96 Proceedings of the fourth international conference on on Parallel and distributed information systems
Efficient evaluation of queries in a mediator for WebSources
Proceedings of the 2002 ACM SIGMOD international conference on Management of data
Cost Models DO Matter: Providing Cost Information for Diverse Data Sources in a Federated System
VLDB '99 Proceedings of the 25th International Conference on Very Large Data Bases
Query Optimization in a Heterogeneous DBMS
VLDB '92 Proceedings of the 18th International Conference on Very Large Data Bases
The Wargo System: Semi-Automatic Wrapper Generation in Presence of Complex Data Access Modes
DEXA '02 Proceedings of the 13th International Workshop on Database and Expert Systems Applications
Leveraging Mediator Cost Models with Heterogeneous Data Sources
ICDE '98 Proceedings of the Fourteenth International Conference on Data Engineering
Evolutionary techniques for updating query cost models in a dynamic multidatabase environment
The VLDB Journal — The International Journal on Very Large Data Bases
Adding Physical Optimization to Cost Models in Information Mediators
ICEBE '05 Proceedings of the IEEE International Conference on e-Business Engineering
The denodo data integration platform
VLDB '02 Proceedings of the 28th international conference on Very Large Data Bases
A Component-Based Approach for Engineering Enterprise Mashups
ICWE '9 Proceedings of the 9th International Conference on Web Engineering
Hi-index | 0.00 |
Optimizing accesses to sources in a mediator/wrapper environment is a critical need. Due to a variety of reasons, relational-based optimization techniques are of no use when having to handle HTTP-based web sources, so new approaches which take into account client/server communication costs must be devised. This paper describes a cost model that stores values from a complete set of web source-focused parameters obtained by the web wrappers, by using a novel updating technique that handles the values measured by the wrappers in previous query executions, and generates a new model instance in each new iteration with an efficient processing cost. This instance allows rapid value updates caused by changes of the server quality or bandwidth, so typical in this context. The results of these techniques are demonstrated both theoretically and by means of an implementation showing how performance improves in real-world web sources when compared to classical approaches.