Existing xml query pattern-based caching strategies focus on extracting the set of frequently issued query pattern trees (qpt) based on the support of the qpts in the history. These approaches ignore the evolutionary features of the qpts. In this paper, we propose a novel type of query pattern called conserved query paths (cqp) for efficient caching by integrating the support and evolutionary features together. cqps are paths in qpts that never change or do not change significantly most of the time (if not always) in terms of their support values during a specific time period. We proposed a set of algorithms to extract frequent cqps (fcqps) and infrequent cqps (icqps) and rank these query paths using evolution-conscious ranking functions. Then, these ranked query paths are used in evolution-conscious caching strategy for efficient xml query processing. Finally, we report our experimental results to show that our strategy is superior to previous qpt-based caching approaches.
Sourav S. Bhowmick