KDS-CM:A Cache Mechanism Based on Top-K Data Source for Deep Web Query

来源 :Wuhan University Journal of Natural Sciences | 被引量 : 0次 | 上传用户:Mr_Sunfox
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Caching is an important technique to enhance the effi-ciency of query processing. Unfortunately,traditional caching mechanisms are not efficient for deep Web because of storage space and dynamic maintenance limitations. In this paper,we present on providing a cache mechanism based on Top-K data source(KDS-CM) instead of result records for deep Web query. By integrating techniques from IR and Top-K,a data reorganiza-tion strategy is presented to model KDS-CM. Also some measures about cache management and optimization are proposed to im-prove the performances of cache effectively. Experimental results show the benefits of KDS-CM in execution cost and dynamic maintenance when compared with various alternate strategies. Caching is an important technique to enhance the effi-ciency of query processing. Unfortunately, traditional caching mechanisms are not efficient for deep Web because of storage space and dynamic maintenance limitations. In this paper, we present on providing a cache mechanism based on Top- By integrating techniques from IR and Top-K, a data reorganiza tion strategy is presented to model KDS-CM. Also some measures about cache management and optimization are proposed to im-prove the performances of cache effectively. Experimental results show the benefits of KDS-CM in execution cost and dynamic maintenance when compared with various alternate strategies.
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