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For example, a data model for a city would include a list of data layers to be included (e.g., roads, buildings, parcels, zoning), with each being specified with the type of generic spatial data model being used (e.g. raster or vector), choices of parameters such as coordinate system, and its attribute columns.
Vector data can be displayed as vector graphics used on traditional maps, whereas raster data will appear as an image that may have a blocky appearance for object boundaries. (depending on the resolution of the raster file). Vector data can be easier to register, scale, and re-project, which can simplify combining vector layers from different ...
In a field-based data model, this information is usually stored at different layers and it is harder to extract different information from various layers. This data model can be applied above the ER as in GERM model and GISER. S.Shekhar introduces direction as a spatial object and presents a solution to object-direction-based queries.
The core functionality added by a spatial extension to a database is one or more spatial datatypes, which allow for the storage of spatial data as attribute values in a table. [4] Most commonly, a single spatial value would be a geometric primitive (point, line, polygon, etc.) based on the vector data model.
A georelational data model is a geographic data model that represents geographic features as an interrelated set of spatial and attribute data. The georelational model was the dominant form of vector file format during the 1980s and 1990s, including the Esri coverage and Shapefile .
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)
Data management, including the creation, editing, and storage of geographic data, as well as transformations such as changing coordinate systems and converting between raster and vector models. Spatial analysis, including a range of processing tools from basic queries to advanced algorithms such as network analysis and vector overlay
Public domain vector and raster dataset. Supported by the NACIS. [1] Global Map: Provides consistent coverage of all the Earth's land cover area. Includes different thematic maps such as: transportation, elevation, drainage, vegetation, administrative boundaries, land cover, population centres, and land use. Registration required. [2] FABDEM