Developing an incremental updating system
Basheer Haj-Yehia, Ammatzia Peled
This paper presents an incremental updating system which developed to update a spatial database from different environments. In this case we need to update a 3D ATLAS-DSP database based on a 2D orthophoto. According to the technical specifications of the project we have to keep the height (Z) values for the unchanged objects. But the new objects will be added without the height values. Besides, for reshaped objects we have to keep the height values for the unchanged vertices. In addition, updating attributes required, such as type-code.
Due to budget limitations we choose to implement the updating operations in the Arc/GIS software. This software was chosen because it is already extant in our company. Furthermore it was complicated to convert whole database from ATLAS format to ESRI shapefiles format and backward. So we come to a decision to carry out the updating by three steps: (a) converting part of the existing database from ATLAS files to ESRI Shapefiles; (b) updating the shapefiles using the Arc/GIS software and in the same time storing the updating operation into special files; and finally (c) implementing the saved updating operations into the original database. It this paper we describe how the updating operations were saved and the parameters needed to be save to enable automatic implementation of these operation into the original database.