Geographic Database Engine Based On Relational Database Research And Practice

This paper took SDE as research object. After describing the conception of SDE, the essential and characteristic of SDE, the four main aspects of SDE-data model, data index, network transfer and manage tools were studyed .On the aspect of data model, based on improving and extending the GDF data model, the data model of SDE was put forwad. The data model can express multi-section data and semantic relations between different feature layers. It support segment attributions, so can express a segmental attribution of a line feature. It also supports multimedia data type. Some compare tests have been done on different ways of storing data in database. On the aspect of data index, the essential of spatial index was advanced based on database, and a spatial index method called the spatial grid index method was put forward based on two phases database query. On the aspect of data network transfer , there is a Network Transfer Protocol for Geographic Data 桽DTP in the paper, and the Protocol has been realized on windows 2000 by using SOCKET. The Geographic Data compress method has been studyed in-depth. On the aspect of manage tools, a manage tool sets has been constructed based on analyzing the construct method of manage tools of oracle database.This paper sumed up the following work in the end.