针对GIS数据库的联动更新及其拓扑一致性维护困难的问题,提出一种基于拓扑联动的增量更新方法,其是针对不同目标类型,分析归纳出相应的拓扑联动类型及其细分类型;对不同目标发展根据其语义特点、拓扑一致性约束条件及变化前后目标问的拓扑关系来推断实体变化类型的规则,并以此为基础分析或推断出每种拓扑联动类型中原关联目标和新生目标的变化情况,进而设计和执行相应的更新操作实现数据库的局部联动更新及其拓扑一致性维护。全文以地籍数据库更新为例,将地籍变更分为地块合并、分割、公共边界调整、结点移动、复合分并5种基本联动类型,并对地块合并、分割、公共边界调整进行了细分,共分为17种细分类型;归纳出地块目标的变化类型推断规则,用实际与模拟数据对本文所提出的方法进行实验验证。本文所提出的方法为此类系统的设计与开发提供了一条新的思路。
In order to maintain the topological consistency during updating, an incremental updating method of spatial database based on the topological linkage is proposed in this paper. In this method, for each kinds of entity, the basic topological linkages are analysed, if necessary they will be subdivided until the state of each entity involved and their topological relationship can be determined. A set of rules used to determine the change type of each entity should be concluded based on the entity's semantic, topological consistency rules, and the topological relations between the involved entities before and after the change. Then the changes of each involved entity will be inferred according to these rules. A set of updating operators mapping the spatial chan- ges of entities to the corresponding objects' state changes are designed and implemented. The incremental updating of cadastral database is used as an example to illustrate this method, cadastral spatial changes are divided to five basic types: union, split, modification of common border, reallocation and node moving. Union, split, modification of common border are subdivided to 17 cases. The spatial change determination rules of cadastral entities are presented. The approach was implemented using VC++ in Oraclegi Spatial and MapX platform, the algorithms are checked by real and simulation data.