Overlaps(g1,g2)

Returns 1 or 0 to indicate whether g1 spatially overlaps g2. The term
spatially overlaps is used if two geometries intersect and their
intersection results in a geometry of the same dimension but not equal
to either of the given geometries.

URL: http://dev.mysql.com/doc/refman/5.1/en/functions-that-test-spatial-relationships-between-geometries.html

