The term spatial data signifies all geometric objects of different dimensions and the relations that could bind these objects together. Spatial data is, in general, divided into two parts: crisp spatial data and vague spatial data. Crisp spatial data has determinate coordinates and boundaries, whereas vague spatial data has indeterminate ones. The demand for spatial data support in database management systems is growing every day, yet not all commercial products provide spatial data support natively, and those that do merely provide it partially. Since database management systems are at the heart ...