Dynamic Optimization of Subquery Processing in Grid Database

Grid database is a new research area combined with the database techniques and Grid techniques, while traditional database query and optimization techniques couldn't fully satisfy the need of Grid database because of the dynamic properties of Grid Nodes. The paper brings forward a query plan model/ NSN based on Petri net so as to describe the data relation between subquery and nodes. Based on NSN model paper further puts forward a three phases algorithm / TPs which can make dynamic optimization for subquery processing to fit for fluctuation of environment in grid , Finally the paper tests the algorithms through experiment.