关键词: 空间数据库, 线段, 索引结构, CB树

Abstract: Point, line and region are three basic entities which constitute vector-based objects in spatial databases. Existing index structures can effectively organize the objects such as points, regions into hash or hierarchical directory, and provide accurate retrieval methods. However the following questions arise when such methods are applied to line segments. Spatial information of line segments may not be precisely expressed which impedes high-quality conservation of line segments. In the hierarchical directory, a lot of dead space and overlapping regions will be generated between nodes, which degrade the performance over time. The paper presents the index structure CB-tree based on data compression. Compared with R-tree, CB-tree has optimum query efficiency, takes up less storage space.

Key words: spatial database, line segment, index structure, CB-tree