Users usually think of the geodatabase as a physical store of their geographic information—primarily using a DBMS or file system. In addition to being a physical instance of a collection of datasets, each geodatabase has some key additional aspects:
Geodatabases have a comprehensive information model for representing and managing geographic information. This comprehensive information model is implemented as a series of simple data tables holding feature classes, raster datasets, and attributes. In addition, advanced GIS data objects add GIS behavior, rules for managing spatial integrity, and tools for working with numerous spatial relationships of the core features, rasters, and attributes.
Geodatabase software logic provides the common application logic used throughout ArcGIS for accessing and working with all geographic data in a variety of files and formats. This supports working with the geodatabase, certainly. But it also includes working with shapefiles, CAD files, TINs, grids, CAD data, imagery, GML files, and numerous other GIS data sources.
Geodatabases have a transaction model for managing GIS data workflows.
Each of these aspects of the geodatabase is described in the following topics in more detail.
