在进行空间数据叠加分析的实际应用中，发现Oracle Spatial处理空间数据的一个缺陷，并得到Oracle公司的确认(bug号：3146244)。针对Oracle Spatial处理海量地理空间数据的不足，提出了坐标概化叠加算法，根据空间叠加分析精度要求，选择合适的容许限值，并以此开发了一个扩展模块。另外还给出了应用该扩展模块进行1：400万全国市县行政图与全国土地利用图的空间叠加分析的实例。采用Oracle Spatial处理出错的数据进行测试，其结果验证了该方法的正确性和有效性。

ve spatial data, an algorithm of“Coordinate-consolidation Overlay”was presented. The appropriate threshold value was selected according to analysis of spatial data overlay. An extended module was developed based on this algorithm in Oracle Spatial. The correctness and validity of the solution were testified by using the spatial data in which bug happened for Oracle Spatial. In the end, an application example in overlay analyses of nationwide municipality-county map and land-use map at scale 1∶4000 000 was given by using the extended module of Oracle Spatial.