MySQL/Language/Spatial databases

Principle
When typing the fields, some of them represent graphical objects, and so are considered like as "Spatial". Consequently, they are manipulated by some different request than for the text.

We distinguish eight fields types :
 * Geometry
 * Point
 * LineString
 * Polygon
 * MultiPoint
 * MultiLineString
 * MultiPolygon
 * GeometryCollection

And six relations between them :
 * Contains
 * Disjoint
 * Equals
 * Intersects
 * Overlaps
 * Within