基于谓词分类的语义缓存查询裁剪

语义缓存在移动环境下有着广阔的前景.查询裁剪是语义缓存的一个重要的问题,传统的查询裁剪在时间复杂度和空间复杂度上存在巨大的局限性,这在一定的程度上限制了语义缓存的实用性.为了克服传统查询的缺点,本文从查询谓词分类着手,把谓词按照语义进行匹配满足,提出了新的剩余查询裁剪算法；新的查询裁剪算法一步生成,不需要优化.算法分析很明显从理论和实验上证明了它的优越性.

Query Trimming based Predication Classifying for Semantic Cache

In order to overcome the high complexity of the traditional query-trimming algorithm in time and space domains, a query-trimming algorithm for semantic cache is proposed based on predicate classification. In the proposed algorithm, all predicates are first divided into two different categories, namely restricted predicate and range predicate, which are then defined as semantic satisfaction, semantic intersection and semantic inclusion. Afterwards, a new query-trimming algorithm is presented, with its complexity being also analyzed. The proposed trimming algorithm is finally compared with the traditional serial trimming algorithm based on predicate model and with the trimming algorithm based on logic rules. Simulated results show that the proposed algorithm greatly improves the query-trimming efficiency, especially in the case of intersection between query and cache.