Extracting Query Results from Semantic Cache
Ting Wu · Chinese Journal of Computers · 2002
This paper first defines query related cache item, extended attribute set and derivability, which are important concepts in extracting query results from cache, and then gives the sufficient condition to derive query. In the second part, different match types between cache and query, including exact match, containing match and overlap match, are defined. When query and cache item are exact match, query predicate is the same as cache predicate. When they are containing match, which means query result are completely contained in cache, query predicate must be implied by cache predicate. Authors present sufficient condition and corresponding algorithm to determine the implication relationship between query and cache predicate. When query and cache item are overlap match, only part of query result is in the cache. Authors also define query trim to trim the part that can be answered from cache and show different trimmed results in different overlap situation. Finally, this paper gives an algorithm to determine a trimmable overlap.Based on the work in this paper, query results can be extracted from semantic cache. Thus, query can take full advantage of local cache, which greatly lowers network bandwidth cost, improves query response time and supports data access during mobile disconnection.