Aspects of the implementation of the GEOVIEW design

Abstract

Abstract GEOVIEW, an integrated system, uses relational database technology and a graphics package (Graphical Kernel System) to offer a flexible environment in which to develop applications of geographical information systems (GIS). It has facilities to represent data in different spatial data structures. Data are stored and retrieved efficiently by using variable length raw data. The unified representation offers the benefit of storing entities in a single relation and eases the process of overlaying different entities. GEOVIEW also provides a mechanism for tailoring user interfaces to suit the needs of different applications by means of a facility to generate macros and menus. Processing requirements for GIS applications can be supported by using tools provided by relational database technology and by graphics packages. High-level language interfaces which can process dynamic statements and bind dynamic variables are needed to develop an efficient database interface module. A graphics segment facility is essential to provide editing functions and to maximize the use of the local processing power of graphics workstations in the graphics interface module. Further improvements in performance can be made by using the array fetch facility and linear keys for spatial searching.