Why Data Models?
Nearly all GIS practitioners require data from multiple sources. To effectively build and share commonly used layers, GIS users should follow a set of common content standards or common data model designs. By working with our user community, Esri has been actively engaged in designing a series of GIS data models using topology and other new capabilities included in the upcoming release of ArcGIS 8.3. These data models cover a number of thematic layers, including census and administrative units, topographic basemaps for 1:24,000-scale maps, hydrography, raster imagery and elevation catalogs, transportation, Public Land Survey System (PLSS), parcels, water facilities, and numerous other efforts. Esri wants to build and share database designs that can be used by any GIS organization regardless of the software they are using. The accompanying articles review the data model design methodology, the elements of a data model, and lessons learned. The creation and distribution of the ArcGIS dat
