Cost-based unbalanced R-trees

Abstract

Cost-based unbalanced R-trees (CUR-trees) are a cost-function based data structure for spatial data. CUR-trees are constructed specifically to improve the evaluation of intersection queries, the most basic selection query in an R-tree. A CUR-tree is built taking into account a given query distribution for the queries and a cost model for their execution. Depending on the expected frequency of access, objects or subtrees are stored higher up in the tree. After each insertion in the tree, local reorganizations of a node and its children have their expected query cost evaluated, and a reorganization is performed if this is beneficial. No strict balancing of the trees applies allowing the tree t..