Spatial Databases SpatiaLite & PostGIS

Spatial Databases An ordinary database has strings, numbers, and dates. A spatial database adds one or more additional types for representing geographic features. The basic geographic types are: GEOMETRY (abstract superclass) POINT (a single coordinate, usually but not necessarily two dimensional) LINESTRING (a set of two or more coordinates, with a linear interpretation of the path between the coordinates) LINEARRING (a linestring of three or more coordinates in which the start and end points are the same, usually used to build polygons) POLYGON (a set of one or more closed linearrings, one exterior ring that defines a bounded area, and a set of interior rings that define exceptions (holes) to the bounded areas) MULTIPOINT (a set of points) MULTILINESTRING (a set of linestrings) MULTIPOLYGON (a set of polygons) GEOMETRYCOLLECTION (a heterogeneous set of geometries)

SpatiaLite Spatially enables SQLite SQLite is a simple, robust, easy to use and really lightweight DBMS Each SQLite database is simply a file You can freely copy it, compress it, put it on a network They are also portable; the same database file will work on Windows, Linux & MacOS

SpatiaLite Can be read by QGIS Analogous to an ESRI File Geodatabase Comes with a standalone executable GUI tool Can import and export ESRI shapefiles

PostGIS Spatially enables PostgreSQL PostgreSQL is a FOSS robust enterprise relational database Analogous to ESRI's Spatial Database Engine (SDE) Developed by Refractions Research Released in May 2001

PostGIS PostGIS data can be used by: QGIS UDIG GRASS GIS MapServer GeoServer OGR ArcGIS