Multiple geometric forms are supported by the Oracle Spatial Option to represent
many different types of spatial data, including points and point clusters, lines and
line strings, polygons and complex polygons with holes, arc strings, line strings,
compound polygons, and circles. You can determine the interaction of these features
through the use of operators such as touch, overlap, inside, and disjoint.
Data that shares the same object space and coordinates but represents different characteristics
(such as physical and economic) is often modeled in layers. Each layer is
divided into tiles representing smaller subareas within the larger area. A representation
of this tile is stored with a spatial index that provides for quick lookups of multiple
characteristics in the same tile. The Spatial Option uses these representations to rapidly
retrieve data based on spatial characteristics. For example, youcan perform a
query against a physical area to examine where pollutants, minerals, and water are
Figure 14-2. Geographic Information System display of a spatial query
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