Query transformation method by delaunay triangulation for multi-source distributed spatial database systems

ABSTRACT

One of the difficulties in building a distributed GIS comes from the heterogeneity of spatial databases. In particular, positional mismatches between spatial databases arise due to several reasons, such as different scales, or different ground control points. They result in unreliable outputs of query processing. One simple solution is to correct positional data in spatial databases at each site, according to the most accurate one. This solution is however not practical in most of the cases where the autonomy of each database should be respected. In this paper, we propose a spatial query processing method without correcting positional data in each spatial database. Instead of correcting positional data, we dynamically transform a given query region or position onto each space where spatial objects of each site are located. Our method is based on an elastic transformation method by delaunay triangulation.

REFERENCES

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INDEX TERMS

Primary Classification:
  H. Information Systems
  H.2 DATABASE MANAGEMENT
      H.2.8 Database applications
          Subjects: Spatial databases and GIS

Additional Classification:
  H. Information Systems
  H.2 DATABASE MANAGEMENT
      H.2.4 Systems
          Subjects: Distributed databases; Query processing

General Terms:
Design, Theory