Formal Data Structures and Query Spaces

Geo-information systems (GIS) are a special class of information systems, they handle data referring to objects and processes at the earth surface. Geometry is the important aspect of these data, setting GIS apart from other information systems. The geometric aspect is also found in CAD systems, but those systems emphasise on construction tasks, whereas GIS generaly emphasise on spatial analysis and spatial monitoring and management. Due to this difference the requirements for spatial data structures are different for CAD and GIS in addition to the fact that GIS also require a link between geometry and attribute data, whereas this link is less dominant in CAD.