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Optimization of Wrappers and Mediators for Web Accessible Data Sources (WebSources) (1998)
| Content Provider | CiteSeerX |
|---|---|
| Author | Vidal, Mar'Ia Esther Vidal, María Esther Bright, Laura Raschid, Louiqa |
| Abstract | This paper studies opportunities for optimization that are typical to WebSources and that will allow the mediator to choose a possibly optimal execution plan. These opportunities exist at the wrapper level, at the mediator level, and at the interface of the wrapper and mediator. At the wrapper level, a wrapper typically utilizes an extractor to extract objects by following links to multiple pages on the WebSource. For optimization, the number of accesses to the WebSource, across some wide-area network, or duplicate accesses to the same page by the extractor, must be minimized. The wrapper will also provide a cost estimation of the wrapper query. This cost will be used by the mediator to select a possibly optimal mediator plan. At the mediator level, the mediator has to explore the space of possibly execution plans to choose the one with the lowest cost. The mediator must be provided with knowledge about the capabilities of the sources, so that only safe queries are generated. Another optimization objective is to ensure the mediator enumerates only the space of safe maximal |
| File Format | |
| Journal | Workshop Web Inf. Data Management (WIDM), Washington DC |
| Publisher Date | 1998-01-01 |
| Access Restriction | Open |
| Subject Keyword | Paper Study Opportunity Optimization Objective Optimal Mediator Plan Mediator Level Safe Query Web Accessible Data Source Execution Plan Cost Estimation Safe Maximal Wrapper Query Duplicate Access Optimal Execution Plan |
| Content Type | Text |
| Resource Type | Conference Proceedings Article |
