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Design of a spatial data structure using the relational normal forms
Authors:JAN W VAN ROESSEL
Institution:EROS Data Center , U.S. Geological Survey , Sioux Falls, South Dakota, 57198, U.S.A
Abstract:Abstract

In previous work, a relational data structure aimed at the exchange of spatial data between systems was developed. As this data structure was relational it was of first normal form, but compliance with the higher normal forms was not investigated. Recently, a new procedural method for composing fully normalized data structures from the basic data fields has been developed by H. C. Smith, as an alternative to the process of non-loss decomposition which is difficult to understand. Smith's method has been applied to data fields required to store points, lines and polygons in a chain-node spatial data model. When geographic domain, coverage layer and map are also considered, the procedure naturally leads to a catalogue model, needed for the exchange of spatial data. Although the method produces a fully normalized data structure, it is not as easy to identify which normal forms are responsible for the ultimate arrangement of the data fields into relations, but the benefits of these criteria for data base development also apply to spatial data structures and related ancillary data.
Keywords:Events  Topology  Graphs  Spatio‐temporal  Dynamic  Field  Regions
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