PostGIS is an extension for PostgreSQL that adds geographic information system (GIS) capabilities to the database server.
Developed by Refractions Research Inc in open source spatial database technology, PostGIS is released under the GNU General Public License. The company has embraced the idea of enhancing the technology for data loading and dumping, user interface tools for direct data access and manipulation, as well as support for advanced topologies at the server side, such as coverages, networks, and surfaces.
Several open source tools are now available that work with PostGIS. For instance, the uDig project is working on a full read and write desktop environment that can work with PostGIS directly. For internet mapping, the University of Minnesota Mapserver can use PostGIS as a data source. The GeoTools Java GIS toolkit has PostGIS support, as does the GeoServer Web Feature Server. GRASS now supports PostGIS as a data source, through the PostGRASS driver. The JUMP Java desktop GIS viewer has a simple plugin for reading PostGIS data, and the QGIS desktop has good PostGIS support.
PostGIS allows for the export of data in several output GIS formats using the OGR C++ library and command-line tools, as well as the bundled Shape file dumper. It is also compatible with several programming languages, including Perl, PHP, Python, TCL, C, C++, Java, and more.
In terms of installation, simply un-tar the PostGIS tar-ball in the 'contrib' directory of your PostgreSQL source tree. You must have the PL/pgSQL procedural language installed before installing PostGIS. Finally, you must untar the PostGIS source there for the Makefile to work.
PostGIS requires a complete configured and built PostgreSQL source code tree, and it uses definitions from the PostgreSQL configure/build process to conform to the specific platform you are building on. Additionally, a GNU C compiler (gcc) is required, as well as GNU Make (gmake or make). It is recommended to have the Proj4 reprojection library and the GEOS geometry library to provide coordinate reprojection support within PostGIS and geometry tests and operations (Buffer(), GeomUnion(), Difference()) within PostGIS, respectively.
Overall, PostGIS is a reliable software that comes with a lot of features and benefits for users. With this software in place, you can easily enhance your PostgreSQL server to be able to work with numerous GIS databases while featuring a capable set of tools for data handling and manipulation.
Version 1.3.5: N/A