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A shape-"file" actually consisted of several files, including at the very least a .shp file to store the geometry, and a .dbf file for the attributes, the latter directly adopting the dBase format that was the dominant microcomputer database at the time (despite it being a proprietary trade secret, the .dbf format had been legally reverse ...
In each of the .shp, .shx, and .dbf files, the shapes in each file correspond to each other in sequence (i.e., the first record in the .shp file corresponds to the first record in the .shx and .dbf files, etc.). The .shp and .shx files have various fields with different endianness, so an implementer of the file formats must be very careful to ...
In this example from Soller and others (1999), [32] the upper surface of each buried geologic unit was represented in raster format as an ArcInfo Grid file. The middle grid is the uppermost surface of an economically important aquifer, the Mahomet Sand, which fills a pre- and inter-glacial valley carved into the bedrock surface.
This was most common from the 1970s through the early 1990s, because GIS software developers had to invent their own geometry data structures, but incorporated existing relational database file formats for the attributes. For example, the Esri Shapefile format includes the .dbf file from the DOS dBase software.
In geographic information systems, a feature is an object that can have a geographic location and other properties. [1] Common types of geometries include points, arcs, and polygons. Carriageways and cadastres are examples of feature data. Features can be labeled when displayed on a map.
GML defines features distinct from geometry objects. A feature is an application object that represents a physical entity, e.g. a building, a river, or a person. A feature may or may not have geometric aspects. A geometry object defines a location or region instead of a physical entity, and hence is different from a feature.
The origin of the geodatabase was in the mid-1990s during the emergence of the first spatial databases.One early approach to integrating relational databases and GIS was the use of server middleware, a third-party program that stores the spatial data in database tables in a custom format, and translates it dynamically into a logical model that can be understood by the client software.
Simple Features – specification for vector data storage (by Open Geospatial Consortium) that can be used in a GML container; GeoJSON – open, lightweight format based on JSON, used by many open source GIS packages; GeoMedia – Microsoft Access based format for spatial vector storage (by Intergraph)