Distributed geographic structure query language DGSQL
CHEN Zhan-long①②, WU Xin-cai①, XIE Zhong①, WU Liang①(①Faculty of Information Engineering, China University of Geosciences, Wuhan 430074,China;②China GIS Software Research and Application Engineering Center of the Ministry of Education, Wuhan 430074)
Combined with Spatial data model of MAPGIS7.0, this article proposed distributed structure query language (DGSQL), and designed the interpreter of DGSQL. It also built the mapping model from global spatial query sentence to local query sentence. Hence, DGSQL can support the query of distributed spatial data. Finally it realized the spatial relation operation (Equal, Intersection, Union, Difference) and synthesized operation (Length, Buffer, intersecting region) and so on.