IsSimple(g)

In MySQL 5.5, this function is a placeholder that always returns 0.

The description of each instantiable geometric class given earlier in
the chapter includes the specific conditions that cause an instance of
that class to be classified as not simple. (See [HELP Geometry
hierarchy].)

URL: http://dev.mysql.com/doc/refman/5.5/en/gis-general-property-functions.html

