Spatial Data Types The Open Geospatial Consortium publishes the  OpenGISfi Implementation Standard for Geographic information - Simple feature access - Part 2: SQL option , a document that proposes several conceptual ways for extending an SQL RDBMS to support spatial data. This specification is available from the OGC website at http://www.opengeospatial.org/standards/sfs. Following the OGC specification, MySQL implements spatial extensions as a subset of the  SQL with Geometry Types  environment. This term refers to an SQL environment that has been extended with a set of geometry types. A geometry-valued SQL column is implemented as a column that has a geometry type. The specification describes a set of SQL geometry types, as well as functions on those types to create and analyze geometry values. MySQL spatial extensions enable the generation, storage, and analysis of geographic features: The spatial data types and functions are available for  MyISAM ,  InnoDB ,  NDB , and  ARCHIVE  tables. For indexing spatial columns,  MyISAM  and  InnoDB  support both  SPATIAL  and non- SPATIAL  indexes. The other storage engines support non- SPATIAL  indexes, as described in Section 13.1.15, “CREATE INDEX Statement” . A  geographic feature  is anything in the world that has a location. A feature can be: Some documents use the term  geospatial feature  to refer to geographic features. Geometry  is another word that denotes a geographic feature. Originally the word  geometry  meant measurement of the earth. Another meaning comes from cartography, referring to the geometric features that cartographers use to map the world. The discussion here considers these terms synonymous:  geographic feature ,  geospatial feature , feature , or  geometry . The term most commonly used is  geometry , defined as  a point or an aggregate of points representing anything in the world that has a location . The following material covers these topics: •Data types for representing spatial values •Functions for manipulating spatial values •Spatial indexing for improved access times to spatial columns •An entity. For example, a mountain, a pond, a city. •A space. For example, town district, the tropics. •A definable location. For example, a crossroad, as a particular place where two streets intersect. •The spatial data types implemented in MySQL model •The basis of the spatial extensions in the OpenGIS geometry model •Data formats for representing spatial data •How to use spatial data in MySQL •Use of indexing for spatial data •MySQL differences from the OpenGIS specification For information about functions that operate on spatial data, see Section 12.17, “Spatial Analysis Functions” . 2049