A Semantic Caching Scheme for Wrappers in Web Databases

We present a new semantic caching scheme suitable for wrappers in web databases. Since the web sources in web databases have typically weaker querying capabilities than conventional databases, it is not trivial to apply existing semantic caching schemes directly. We provide a seamlessly integrated query translation and capability mapping between the wrappers and web sources in the semantic caching to cope with such di culties and describe several related issues. In addition, an analysis on the match types between the user's input query and queries stored in the cache is presented. We show how to use semantic knowledge acquired from the data to avoid unnecessary access to web sources by transforming the cache miss to the cache hit. Further, a polynomial time algorithm based on the extended and knowledge-based matching is proposed to nd the best matched query in the cache. Finally, experimental results are presented to illustrate the e ectiveness of our proposed semantic caching scheme.

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