PostGIS
Encyclopedia
PostGIS is an open source software program that adds support for geographic objects to the PostgreSQL
object-relational database. PostGIS follows the Simple Features
for SQL specification from the Open Geospatial Consortium
(OGC).
The PostGIS implementation is based on "light-weight" geometries and indexes optimized to reduce disk and memory footprint. Using light-weight geometries helps servers increase the amount of data migrated up from physical disk storage into RAM, improving query performance substantially.
PostGIS is registered as "implements the specified standard" for "Simple Features for SQL" by the OGC. PostGIS has not been certified as compliant by the OGC. For the OGC's definition of compliant, see What does "Compliant" mean?.
. A stable "1.0" version was released on April 19, 2005, which followed 6 release candidates. In 2006, PostGIS was registered as "implements the specified standard" for "Simple Features for SQL" by the OGC.
See http://www.refractions.net/products/postgis/history/
PostgreSQL
PostgreSQL, often simply Postgres, is an object-relational database management system available for many platforms including Linux, FreeBSD, Solaris, MS Windows and Mac OS X. It is released under the PostgreSQL License, which is an MIT-style license, and is thus free and open source software...
object-relational database. PostGIS follows the Simple Features
Simple Features
Simple feature access , is both an OpenGIS and ISO Standard that specifies a common storage model of geographical data using well-known text . The geometries are also associated with spatial reference systems...
for SQL specification from the Open Geospatial Consortium
Open Geospatial Consortium
The Open Geospatial Consortium , an international voluntary consensus standards organization, originated in 1994. In the OGC, more than 400 commercial, governmental, nonprofit and research organizations worldwide collaborate in a consensus process encouraging development and implementation of open...
(OGC).
Features
- Geometry types for points, linestrings, polygons, multipoints, multilinestrings, multipolygons and geometrycollections.
- Spatial predicates for determining the interactions of geometries using the 3x3 Egenhofer matrix (provided by the GEOS software library).
- Spatial operators for determining geospatial measurements like area, distance, length and perimeter.
- Spatial operators for determining geospatial set operations, like union, difference, symmetric difference and buffers (provided by GEOS).
- R-treeR-treeR-trees are tree data structures used for spatial access methods, i.e., for indexing multi-dimensional information such as geographical coordinates, rectangles or polygons. The R-tree was proposed by Antonin Guttman in 1984 and has found significant use in both research and real-world applications...
-over-GiSTGiSTIn computing, GiST or Generalized Search Tree, is a data structure and API that can be used to build a variety of disk-based search trees. GiST is a generalization of the B+ tree, providing a concurrent and recoverable height-balanced search tree infrastructure without making any assumptions about...
(Generalised Search Tree) spatial indexes for high speed spatial querying. - Index selectivity support, to provide high performance query planQuery planA query plan is an ordered set of steps used to access or modify information in a SQL relational database management system. This is a specific case of the relational model concept of access plans....
s for mixed spatial/non-spatial queries. - For raster data, under development PostGIS WKT Raster (now integrated into PostGIS 2.0 and renamed PostGIS Raster)
The PostGIS implementation is based on "light-weight" geometries and indexes optimized to reduce disk and memory footprint. Using light-weight geometries helps servers increase the amount of data migrated up from physical disk storage into RAM, improving query performance substantially.
PostGIS is registered as "implements the specified standard" for "Simple Features for SQL" by the OGC. PostGIS has not been certified as compliant by the OGC. For the OGC's definition of compliant, see What does "Compliant" mean?.
Users
There are a large number of software products that can use PostGIS as a database backend, including:- ST-Links PgMap
- CadcorpCadcorpComputer Aided Development Corporation Ltd. is a British owned and run company established in 1991. Cadcorp has its headquarters in Stevenage, Hertfordshire, U.K. and a development office in London...
SIS - Everest GIS
- Feature Manipulation EngineFeature Manipulation EngineFME is an integrated collection of Spatial ETL tools for spatial data transformation and data translation produced by Safe Software Inc. of Surrey, British Columbia, Canada...
- GeoMediaGeoMediaGeoMedia is the technology, suite of software components in Intergraph Corporation's geographic information system and family of software products that include: GeoMedia Objects, GeoMedia Viewer , GeoMedia, GeoMedia Professional, GeoMedia WebMap, GeoMedia WebMap Professional and others...
(via 3rd party connectors) - GeoServerGeoServerIn computing, GeoServer - an open-source server written in Java - allows users to share and edit geospatial data. Designed for interoperability, it publishes data from any major spatial data source using open standards...
- GRASS GISGRASS GISGRASS GIS is a free, open source geographical information system capable of handling raster, topological vector, image processing, and graphic data....
(GPL) - gvSIGGvSIGgvSIG is a geographic information system , that is, a desktop application designed for capturing, storing, handling, analyzing and deploying any kind of referenced geographic information in order to solve complex management and planning problems. gvSIG is known for having a user-friendly interface,...
(GPL) - Interoperability Extension from ESRIESRIEsri is a software development and services company providing Geographic Information System software and geodatabase management applications. The headquarters of Esri is in Redlands, California....
- Ionic Red Spider
- KosmoKosmoKosmo is a desktop geographic information system with advanced functions. It is the first of a series of developments that are being made available to the community....
(GPL) - Manifold SystemManifold SystemManifold System is a geographic information system software package developed by manifold.net that runs only on Microsoft Windows. Manifold System handles both vector and raster data, includes spatial SQL, a built-in Internet Map Server , and other general GIS features...
- MapInfo ProfessionalMapInfo ProfessionalMapInfo Professional is a mapping software product produced by MapInfo Corporation.MapInfo Professional has the ability to combine and display, on a single map, data from a variety of sources that are in different formats and projections...
- MapnikMapnikMapnik is an open source mapping toolkit, written in C++ and useful for both desktop- and server-based map rendering. One of its many users is the OpenStreetMap project which uses it in combination with an Apache Web Server module to render tiles that make up the OSM 'Slippy Map' Layer...
(LGPL) - MapDotNet Server
- MapServerMapServerMapServer is an open source development environment for building spatially-enabled internet applications. It can run as a CGI program or via MapScript which supports several programming languages . MapServer was developed by the University of Minnesota — so, it is often and more specifically...
(BSDBSD licensesBSD licenses are a family of permissive free software licenses. The original license was used for the Berkeley Software Distribution , a Unix-like operating system after which it is named....
) - MapGuide (LGPL)
- MezoGIS
- OpenJUMP (GPL)
- Quantum GISQuantum GISQuantum GIS is a free software desktop Geographic Information Systems application that provides data viewing, editing, and analysis capabilities.-Development:...
(GPL) - TerraLibTerraLibTerraLib is an open source GIS software library that extends object-relational DBMS technology to handle spatiotemporal data types. The library supports different DBMS, including MySQL, PostgreSQL, and Oracle. Its vector data model is upwards compliant with OGC) standards...
(LGPL) - TerraViewTerraViewTerraView is an GIS application built on the TerraLib GIS library. TerraView handles vector data and raster data , both of them stored in a relational or geo-relational database, including ACCESS, PostgreSQL, MySQL and Oracle Spatial...
(GPL) - uDigUDiguDig is a GIS software program produced by a community led by Canadian-based consulting company Refractions Research. It is based on the Eclipse platform and features full layered Open Source GIS...
(LGPL) - ArcGISArcGISArcGIS is a suite consisting of a group of geographic information system software products produced by Esri.ArcGIS is a system for working with maps and geographic information...
(via ST-Links PgMap, ZigGIS, ArcSDE and other 3rd party connectors) - CitySurf GlobeCitySurf GlobeCitySurf Globe is a family of Geography 2.0 Geographical Information System software, developed by PiriReis Bilişim Teknolojileri, known as a new model in mapping servers and interaction with the final user....
History
The first version was released in 2001 by Refractions Research under the GNU General Public LicenseGNU General Public License
The GNU General Public License is the most widely used free software license, originally written by Richard Stallman for the GNU Project....
. A stable "1.0" version was released on April 19, 2005, which followed 6 release candidates. In 2006, PostGIS was registered as "implements the specified standard" for "Simple Features for SQL" by the OGC.
See http://www.refractions.net/products/postgis/history/
See also
- Well-known textWell-known textWell-known text is a text markup language for representing vector geometry objects on a map, spatial reference systems of spatial objects and transformations between spatial reference systems. A binary equivalent, known as well-known binary is used to transfer and store the same information on...
and binary, descriptions of geospatial objects used within PostGIS
Reference Book
- PostGIS in Action, Now in Hard-copy April 2011 from Manning Publications.
- PostGIS HTML Documentation.
- PostGIS 1.5.3 PDF Manual.
- PostGIS 2.0.0 PDF In Progress Manual.
- ST-Links PgMap Manual.